RIME2021 proceedings

Proceedings of International e-Conference for Students on Recent Innovations in Mechanical Engineering 2021 EDITED BY: MIHIR CHAUHAN, RUDRESH MAKWANA

Title: Proceedings of International e-Conference for Students on Recent Innovations in Mechanical Engineering 2021 Editors’ name: Dr Mihir Chauhan, Prof. Rudresh Makwana Published by: Self-Published Mechanical Engineering Students Association, Mechanical Engineering Department, Institute of Technology, Nirma University, Ahmedabad 382481. Gujarat, India Printed by: Mechanical Engineering Students’ Association, Ahmedabad Edition: 2021 ISBN: 978-93-5473-550-9 Copyright@ Mechanical Engineering Students Association, ME, ITNU

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 INDEX EXPERIMENTAL INVESTIGATION OF LIMIT FORMING RATIO IN SQUARE HOLE 1 FLANGING OF AL5052 USING SINGLE POINT INCREMENTAL FORMING GAUDANI DARSHANKUMAR; MAKWANA RUDRESHKUMAR AUTOMATIC EMERGENCY BRAKING SYSTEM (AEBS) FOR 4 WHEEL VEHICLES 5 RAJ HARSHALSINH; PATEL BHARAT; PATEL NISARG; SHETH KENIL; MAHESHWARI MOHIT TO ANALYZE THE EFFECT OF VARYING FEEDWATER TEMPERATURE IN BOILER 10 AND ITS EFFECT ON THE OPERATIONAL COST NAIR SANJAY FLOW VISUALIZATION OF FOOTBALLS TO ANALYZE ITS PERFORMANCE AND 14 KNUCKLING EFFECT K. SRAVAN; SHAHISTHA; MENON RITHWIK; BABU SIDHARTH CONDENSER JACKET 20 BATTULA SUNIL;PEYYALA ANUSHA;MOVVA NAGA SWAPNA SRI;BAKKA SANTHOSH;KUCHIPUDI JAYANTH;AVUTAPALLI DINESH. DESIGN AND EXPERIMENTATION OF ARROW THROWING MECHANISM FOR 25 ROBOCON 2021 SHETH KUSHAL; SHEKHDA DHRUMIL; VASJARIYA ABHAY; CHAUHAN MIHIR; MECWAN AKASH SIMPLIFICATION OF BEARING FAULT DIAGNOSIS PROCEDURE USING MATLAB 31 APP DESIGNER TOOL RAMCHANDANI ROHIT ; PATEL DHAVAL ; BHOJAWALA VIPUL DETAILED DESIGN OF A QUADRUPED ROBOT BASED ON 5-BAR LINKAGE LEG 36 SHEKHDA DHRUMIL; SHETH KUSHAL; BODA JIGAR; GAJARA PARTH; CHAUHAN MIHIR SIMULATION OF FATIGUE IN HIGH-TEMPERATURE SUPERCONDUCTOR USING 42 MATAKE CRITERION ROBERT JUSTIN; K.B. ASHOK; JACOB THOMAS RIJO MANAGING AND REDUCING SYSTEM FOR SPACE DEBRIS FROM LOW EARTH 48 ORBIT SRIVASTAVA SARTHAK; PITHADIYA FAGUN SUGARCANE JUICE EXTRACTION MACHINE 53 MEHTA DISHANK; PATEL VRAJ

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 DESIGN AND ANALYSIS OF SPUR GEAR USING MATLAB 59 SONI AMAN HYDROGEN POWERED 6-STROKE ENGINE 64 VERMA SHRESTH EXPERIMENTAL STUDY ON SINGLE POINT INCREMENT HOLE FLANGING 69 SHAH VATSAL ; MAKWANA RUDRESHKUMAR EVALUATION OF MAGNETIC REFRIGERATION SYSTEM AS AN ALTERNATIVE TO 74 CONVENTIONAL REFRIGERATION SYSTEM – A REVIEW DOPPALA PRUDHVI RAJU; ANUSHA PEYYALA; MOVVA NAGA SWAPNA SRI ; KOTTAPALLI GANESH; KANTTI AJAY; AMGOTU VASU NAIK APPLICATION OF C# IN MECHANICAL ENGINEERING PROBLEM 82 SHARMA RAHIL; GORAKH RAUNAK DESIGN AND FABRICATION OF FIXED-WING UNMANNED AERIAL VEHICLE (UAV) 87 WITH HIGH PAYLOAD FRACTION IN MICRO CLASS CATEGORY (MCC) SONI VEDANT; PRAGDA VIVEK; PATIL YASHKUMAR BOILER TECHNOLOGY:USING PLASTIC AS AN ALTERNATIVE FUEL 93 CHAUHAN SHUBHANSHUSINGH , PATEL ADITYA , SOLANKI YASHRAJ DESIGN CALCULATIONS AND FABRICATION OF A FOOT OPERATED HAND 99 SANITIZER BHATIA SIDDHARTH, RATNAPARKHE ATHARVA, SHARMA AYUSH SOLAR WATER HEATING WITH SOLAR PLATE COLLECTORS SYSTEMS WITH 105 IMPLEMENTATION OF ANN: A REVIEW VISHWAKARMA PRAMOD; SHARMA AJAY TO ANALYZE THE EFFECT OF VARYING FEED WATER TEMPERATURE IN BOILER 113 THROUGH SOLAR OFF-GRID AND ON-GRID CONNECTIONS TO REDUCE THE FUEL CONSUMPTION. NAIR SANJAY

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 EXPERIMENTAL INVESTIGATION OF LIMIT FORMING RATIO IN SQUARE HOLE FLANGING OF AL5052 USING SINGLE POINT INCREMENTAL FORMING GAUDANI DARSHANKUMAR; MAKWANA RUDRESHKUMAR Institute of technology, Nirma University, Ahmedabad (382481), Gujarat, India ABSTRACT: The single-point incremental forming process (SPIF) is an emerging technology worldwide. A hole flange has been considered for the study and fabricated experimentally on the CNC milling machine. This process is used for the difficult to form aluminium sheet. In this study, experiments are performed on Alumin- ium AA5052 sheets to find Limit Forming Ratio of square hole flanging. 1 INTRODUCTION Sheet metal forming is a process to form the metal sheet in the desired shape. Traditionally dies and punches are used for the sheet metal forming process. The traditional method is convenient for mass production only. However, small size lot is being built on the desire and versatility of customers, but the making of various dies is costly as well as the changing time of dies increases the lead time for small production. Therefore, the incremental sheet forming (ISF) technique is a modern possibility to decrease the lead time of components in small-volume manufacturing. Leszak [1]first suggested the primary principle of increment shape using a single device. It is call a single-point incremental forming process (SPIF). According to Leszak, the SPIF method was known as the actual die-less forming process. SPIF path is generated in Computer-Aided Manufacturing software and fed into the Vertical Milling Machine. The aluminium plate is fixed with the fixture. The most popular feature of the SPIF method is using a hemispheric tool that is in continuous touch with the piece of work. The sheet is stretched by the tool and extending up to the desired shape; on the other side, the sheet becomes deformed slowly by localized impact. There is no contact with any other support to the outside surface. The final direction depends on the designer configuration of the tool path trajectory. Hole flanging is a method of creating a flange across the opening with the help of SPIF. The tool is used in hole flanging to extend the precut hole surface, create a flat and round flange lip of greater strength. There are various ways to define formability in hole flanging. For example, C. Vallellano et al. [2] define formability limit according to necking and fracture phenomenon then conclude that higher formability will be achieved to the suppuration of necking before the fracture. On the other hand, Jeswiet et al. [3] analyzed the vertical step-down tool path and concluded an insignificant effect on formability. Simultaneously, formability increases with the bending ratio increase. Square hole flanging same as circular hole flanging. VAM Cristino et al. [4] studied the square hole flanging and gave the first-ever contribution towards understanding deformation and mechanics of failure in the square part of hole flanging. They experimented with a square hole with SPIF on AL AA1050 with a 1mm sheet thickness. They concluded that the deformation was associated with various regions according to different strain conditions and suggested the prevention of the flange's failure and suggested changing precut hole side length, corner radios, or both to make a successful flange. 1

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 2 METHODOLOGY 2.1 Material Characterization The research work was carried out on aluminium AA5052 sheets with 1.5mm thickness. Standard tensile test performed on a specimen of aluminium sheet and determined Yield stress, Ultimate tensile strength, Elonga- tion, Poisson’s ratio, and Mass density in the rolling direction. Also, the chemical composition was obtained by Spectro analysis of the same aluminium sheet. Both are shown in Table 1 and 2, respectively. Table 1. Mechanical property of Al 5052 in the rolling direction. Yield strength Ultimate tensile Poisson’s Elongation Mass-den- (%) sity (kg/m3) (MPa) strength (MPa) ratio 14.38 2.68e+10 0֯ RD 194.67 256.175 0.33 Table 2. Chemical Composition of Al 5052 (% by weight) Al Si Fe Cu Mn Zn Ti Cr Mg Ni 97.13 0.068 0.29 0.007 0.06 0.01 0.018 0.21 2.2 0.004 2.2 Experimental Setup The experiments were carried out in a CNC machine. Aluminium sheet fix with the help of fixture. A precut square hole made with a pocket milling machine. Helical tool trajectory fed for tool motion. The tool stretches out the precut square hole in a downward direction to form the final flange. Figure 1 illustrates the experimental setup for square hole flanging. The aluminium AA5052 initial blank with 100x100x1.5 mm was milled to deliver a square precut hole with different side lengths L0 and constant corner radii R0. The forming tool had a hemispherical 10 mm diameter. A tool feed rate of 1000 mm/min and downward feed size of 0.2 mm. The rotation of the tool was 0 rpm, and the corner radii value is 5 mm constant. The experiments start with 40mm of precut square length to 45mm of square length with 1mm of interval. Like 40, 41,42,43,44 and 45 mm. Linear tool path is used for every complete cycle. Figure 1. Experimental setup for square hole flanging 3 RESULT AND DISCUSSION Table 3 summarizes the results of attempting to produce square flanges with round corners by single-stage SPIF using AA5052 blanks with different precut geometries and considering, for example, the influence of the initial side length L0 of the precut hole on the overall formability of the process. The successful flange form at 44mm of precut square length but failed at 43mm. Thus, the successful flange length L is 56mm. 2

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 The formability of flange defines by the limit forming ratio (LFR), which is the ratio of final flange length ‘L’ to precut square length ‘L0’. For example, from Table 4, one can be said that the LFR is 1.272. LFR = (L/L0) = 56/44 = 1.272. The obtained final flange of 44 mm precut length is shown in figure 2 and failed 43 mm precut length flange shown in figure 3. This flange is failed at corner place. Table 3. Experimental work plan for square hole flanging Success/Fail Precut length (mm) Step depth (mm) Feed (mm/min) 40 0.2 1000 Fail 41 0.2 1000 Fail 42 0.2 1000 Fail 43 0.2 1000 Fail 44 0.2 1000 Success 45 0.2 1000 Success Figure 2. Successful square hole flange with 44mm of precut length Figure 3. Failed square hole flange with 43 mm of precut length at right corner 4 CONCLUSIONS From the experiments, one can conclude that a single-stage square hole flanging of Al 5052 material with a thickness of 1.5mm had an LFR of 1.272. However, much work is required for flanging to become a conven- tional process for industrial standard products; for example, work can be done to explore the effect of process parameters on surface roughness, thinning, and geometry accuracy. REFERENCES [1] L. Edward, \"Apparatus and process for incremental dieless forming\". United States Patent US3342051A, 1967. [2] M. Borrego, D. Morales-Palma, A. Martínez-Donaire, G. Centeno and C. Vallellano, \"Experimental study of hole- flanging by single-stage incremental sheet forming,\" Materials Processing Technology, vol. 237, p. 320–330, 2016. [3] J. Jeswiet, F. Micari, G. Hirt, A. Bramley, J. Duflou and J. Allwoodf, \"Asymmetric single point incremental forming of sheet metal,\" CIRP Ann-Manuf Technology, vol. 54, p. 623–49, 2005. [4] V. Cristino, L. Montanari, M. Silva and P. Martins, \"Towards square hole-flanging produced by single point incremen- tal forming,\" Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications, p. 1–9, 2014. [5] V. Mugendiran and A. Gnanavelbabu, \"Analysis of hole flanging on AA5052 alloy by sin-gle point incremental forming process,\" vol. 5, p. 8596–8603, 2018. [6] A. Martínez-Donaire, D. Morales-Palma, M. Borrego, G. Centeno and C. Vallellano, \"On the effect of stress state on the failure limits of hole-flanged parts formed by SPIF,\" Journal of Physics: Conference Series., vol. 1063, 2018. [7] A. Martínez-Donaire, M. Borrego, D. Morales-Palma, G. Centeno and C. Vallellano, \"Analysis of the influence of stress triaxiality on formability of hole-flanging by single-stage SPIF,\" International Journal of Mechanical Sciences, vol. 151, p. 76–84, 2019. [8] A. Martínez-Donaire, D. Morales-Palma, A. Caballero, M. Borrego, G. Centeno and C. Vallellano, \"Numerical explicit analysis of hole flanging by single-stage incremental forming,\" in Procedia Manufacturing, 2017, p. 132–138. 3

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 [9] D. Morales-Palma, M. Borrego, A. Martínez-Donaire, J. López-Fernández, G. Centeno and C. Vallellano, \"Numerical study on the thickness homogenization in hole-flanging by single-point incremental forming,\" Journal of Physics: Conference Series, vol. 1063, 2018. 4

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 AUTOMATIC EMERGENCY BRAKING SYSTEM (AEBS) FOR 4 WHEEL VEHICLES RAJ HARSHALSINH; PATEL BHARAT; PATEL NISARG; SHETH KENIL; MAHESHWARI MOHIT Birla Vishvakarma Mahavidyalaya, Vallabh Vidyanagar, Anand, Gujarat, India ABSTRACT: Affordability of vehicles has increased traffic and because of that there is an increase in accidents. It requires innovative technologies to counter such catastrophe. Advanced automatic braking system improves braking techniques in vehicles which is very much effective and reduces fatality. A prototype was designed using CAD and then fabricated with LIDAR module, Arduino UNO R3 board with PIC microcontroller, motors and mechanical braking arrangement. Test were carried out to estimate the effectivity of Automatic Emergency Braking System (AEBS) Keywords: Automatic braking, AEBS, Collision Mitigation principle, sensors, LiDAR 1 INTRODUCTION In today’s time, driving is a daily activity for most of the people and technology has got so many alternatives which leads to increase in speed resulting road accidents. Common braking system is not sufficient to avoid accidents particularly when driver is in dormant state. It requires advance braking technology such as Automatic Emergency Braking System (AEBS). AEBS is a braking technology which uses sensor and microcontroller system along with the mechanical brakes. AEBS system can prevent accidents completely by stopping the vehicle but in most cases, it just reduces the vehicle speed and alerts the driver about the possibility of collision. In this project, different advanced braking technologies are studied which are capable of effective braking of vehicle. A prototype is designed using CAD and fabricated with all the required mechanical and electrical components to carry out tests in real life conditions by placing obstacles. 2 PRINCIPLE The basic principle behind automatic braking in the prototype is collision mitigation braking system [1]. Sensing of any threat is performed by the fusion of high capability sensors and high-resolution camera technology. Collision warning is indicated by a sound or visual signal. This warns the driver about the possibility of collision and gives time to react to it immediately. Meanwhile, software present in the control unit constantly calculates the threat level based on the sensor data. If proper avoidance action is not taken, software triggers mitigation braking system [2]. Decision algorithm for software are based evaluating the driving conditions and maneuvers for safely passing the obstacle [3]. All the required braking and steering parameters are calculated for every obstacle. If the risk of collision is considerably high, preparation phase is initiated. This prepares emergency braking system and also driver is warned about the collision possibility. Figure 1. Working of 3-D camera [4] 5

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 When the collision becomes inevitable based on the sensor data and reactions of driver after warning, collision mitigation braking is applied. Stopping the car completely is not possible due to high speed so it slows down the vehicle before collision to lower the impact force and damages [1]. Figure 2. AEBS mitigation system [5] 3 SENSORS LiDAR (Light Detection and Ranging) is used for detecting obstacles in this project. LiDAR uses a pulsed laser to calculate an object’s variable distance. There are three primary components of LiDAR Scanner, laser and GPS. LiDAR is used over ultrasonic sensors because of their more sensing distance. LiDAR follows a simple principle — throw laser light at an object and calculate the time it takes to return to the LiDAR source. Given the speed at which the light travels (approximately 186,000 miles per second), the process of measuring the exact distance through LiDAR is incredibly fast. The distance of the object = (Speed of Light x Time of Flight)/ 2 [6] Figure 3. Working of LiDAR sensor [6] 3.1 Limitations of LiDAR Because LiDAR operates through the emission of light pulses, any environmental factor such as rain, dust, humidity in the air, etc. that attenuates the light pulses can affect the LiDAR sensor’s ability to gather data accurately. Also, the obstacle is detected only when it is in the conical field of view of sensor. To overcome this, multiple sensors are placed circumference the vehicle to gather data from all the directions. 6

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 4 DESIGN OF THE PROTOTYPE In the development of the prototype, first thing to do is to design the mechanism using CAD and check its effectivity using simulations. Frame is built with MS metal angles and plates. Frame was prepared with wheelbase to track width ratio as 1.5:1 (ford fiesta reference 1.47:1). On to the frame arrangements are made to mount mechanical mechanism and electrical components. Braking mechanism is mounted on the rear end and steering mechanism on the front end. Both the mechanisms are controlled with the help of Arduino UNO microcontroller. LCD screen is placed to verify and show the results of the sensor and the stopping distance. Front, back, left and right movement of the vehicle is controlled with the help of remote controller. A Johnson motor is attached with the help of links to the brake lever on which brake shoes are mounted. As the motor rotates, lever gets down allowing contact of brake shoe with wheel thus enabling braking. When mitigation braking activates, power supply to motors for the wheels is cut off simultaneously when brakes are applied to the wheels. Steering mechanism is based on Davis steering mechanism where when a servo motor rotates in clockwise direction, front wheel turns right and vice versa. Figure 4. Full frame CAD model Figure 5. Braking and Steering mechanism (CAD model and prototype) 4.1 CALCULATIONS BASED ON MODEL Model Data  Wheel base, L= 0.675 m, Mass, m = 15 kg  Coefficient of friction between road and wheel, μ = o.7 (for dry surface)  Height of center of gravity of the model above the road surface, h=0.05m  Perpendicular distance of CG from rear axle, x= 0.34 m  Retardation of Vehicle = a m/s2 =3.46 m/s2 [7] From above data we get, RA = 66.16 N and RB = 74.068 N. Value of max retardation force is less than 1g which is safe according to norms of automatic braking according to ‘SAE’. 7

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9  Value of braking force, FT = μ.RN = 0.7 (74.068) = 51.847 N  Value of braking torque, TB = FT x r = 51.847 x 0.05 = 2.59 Nm 5 RESULT AND DISCUSSION AEBS prototype is tested in real environment at varying speeds. This test is aimed to find out response of AEBS system. Whether or not it is able to stop the prototype when an obstacle is placed in its path in accordance to the stopping distance set in the software program. Tests are carried out by both placing an obstacle at a distance and by suddenly introducing an obstacle in the prototype’s path. Obstacles placed are of 50 cm x 40 cm size. The path on which test is carried out is flat road. In both the scenario, prototype managed to sense the presence of an obstacle and initiated warnings followed by braking. Table 1. Distance setting for AEBS Prototype distance from the obstacle AEBS response 150 cm Warning on LCD screen 150 cm Warning with sound buzzer 100 cm Activation of automatic braking 5.1 MEASUREMENTS IN REAL CONDITIONS BY SENSOR LCD showing readings of distance in centimetres and the status of operation. Case 1: When distance is < 100 cm it stops and shows status as stopped. Case 2: When distance of obstacle is at >100 cm it shows status as road clear. Figure 6. LCD screen showing results Figure 7. Nissan Intelligent Brake Assist [8] 8

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Due to limitation of field of view of sensor, obstacle placed were comparatively large enough to be detected by the sensor. Prototype being light weight and electrically operated with the help of motors tend to stop very quickly thus stopping time calculated is very less. When the vehicle is heavy and operated at considerably high speeds, mitigation action takes place. Hatchback cars in reality weighing 1000 kg takes around 3 seconds to stop with stopping distance of about 25 m at 40 kmph. Warning are given when the vehicle is around 12 m to 15 m from the obstacle. When functioning at high speeds, stopping the car completely is not possible when driver is not attentive. In that case, brakes are applied to slow down the car and reduce the impact of collision. Table 2. Results from the prototype Stopping time (sec) Speed (RPM) Distance from the object after braking(m) 0.23 0.32 100 0.95 0.41 200 0.80 0.52 300 0.73 0.68 400 0.60 500 0.42 6 CONCLUSION In this study, AEBS was successfully tested on small scale prototype. It is an active safety feature with practical feasibility and has a wide scope of applicability in low budget cars also. It also leads to greater safety standards by reducing the braking distance by almost 30% and avoiding fatality. It is most effective with sensors having long range detection capability like RADAR (8m) and LIDAR (12m) as compared to sensors like ultrasonic sensor. This prototype operated by battery consisted only a single sensor, cars in reality are loaded with multiple sensors and advanced controlling software making them more accurate and responsive. This system works best where traffic-rules and lane driving is followed strictly, as detecting and analysing multiple obstacles at speeds is very difficult. REFERENCES [1] C. Kuchimanchi and S. S. Garimella, \"Collision Warning With Automatic Braking System For Electric Cars,\" International Journal of Mechanical Engineering Research, vol. 5, no. 2, pp. 153-165, 2015. [2] A. Mochammad, H. Gunawan D and M. M, \"Development of Low-Cost Autonomous Emergency Braking System (Aebs) For An Electric Car,\" in International Conference On Electric Vehicular Technology, 2018. [3] BOSCH, [Online]. Available: https://www.bosch.com.cn/en/. [4] \"Working of 3D camera,\" NVIDIA, [Online]. Available: https://Blogs.Nvidia.Com/Blog/2019/04/15/How-Does-A- Self-Driving-Car-See. [Accessed 2021]. [5] M. Ariyanto, \"Development of Low-Cost Autonomous Emergency Braking System (AEBS) for an Electric Car,\" 2018. [6] \"Geospatial World,\" [Online]. Available: https://www.geospatialworld.net/blogs/what-is-lidar-technology-and- how-does-it-work/. [Accessed 2021]. [7] R. S. Khurmi, Theory of Machines, S Chand Publishing House. [8] \"Intelligent Brake Assist,\" Nissan Motor Corporation, [Online]. Available: https://www.nissan- global.com/EN/TECHNOLOGY/OVERVIEW/iba.html. [9] \"Automatic Emergency Braking Systems (AEBS),\" in GRRF Informal Group on Automatic Emergency Braking and Lane Departure Warning Systems, 2009. 9

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 TO ANALYZE THE EFFECT OF VARYING FEEDWATER TEMPERATURE IN BOILER AND ITS EFFECT ON THE OPERATIONAL COST NAIR SANJAY LDRP Institute of Technology and Research, Gandhinagar, Gujarat, India ABSTRACT: These days a lot of money and energy is being invested into the research and development of renewable energy to take seat of the conventional energy resources, since these resources are good to the envi- ronment and are not limited and can supply human beings for a large amount of time without having any side impacts to the surrounding. This study was carried out with the view in mind to try to reduce the fuel combustion in a conventional coal-fired or any gas burnt boiler by making necessary changes in its operating conditions. For concreting the script, necessary case study was done in a regional chemical fertilizer company. And in last we found that by certain takeable steps we can operate our conventional boiler units by having less impact to the environment, plus low operational costs. 1 INTRODUCTION Coal-Fired boilers are widely used for generation of electricity and Heat generation processes. In 2018, the World Total Primary Energy Supply share consisted of Oil (31.6%); Coal (26.9%); Natural gas (22.8%); Nu- clear (4.9%); Hydro (2.5%); Biofuels & Waste (9.3%); Other (2%). The share of Coal and Oil is the largest because of the increased demand for electricity due to booming industrialization and automation, further the share of nuclear, which is clean from environmental perspective, but the materials (radioactive materials) are limited, and the complexity is more in a nuclear based power plant. Further there are hydro and other renewable energy production like wind, wave etc. but the amount of generation from these resources is very limited and cannot meet the demand levels of human race for its everyday consumption levels. In such conditions and reading the research time needed to improve renewable energy technology, it is needed to take some steps to at least lower down the rate at which the harm is inflicted to the environment. The development of methods for improving the efficiency of conventional thermal power plants is strongly forced by more strict environmental limits placed by the government of various countries. This is the reason for continuously applied new methods and techniques for reduction of gas pollutants and optimizes existing systems considering the dynamic changes of external conditions. The efficiency of large-scale coal boilers is relatively high and varies with the change of boiler load, Increasing the thermal efficiency is resulting in lower fuel consumption and lower flue gas emissions. Based on some research an improvement of 0.55% of overall thermal efficiency decreased fuel consumption of 2.06% (11.5 t/h lignite) and reduced CO2 in flue gas of 2.06% (4.8 t/h CO2). To increase the boiler efficiency, some common changes in Operating conditions are to be made such as:  Increasing the average temperature at which heat is supplied.  Decreasing/reducing the temperature at the which heat is rejected. This can be achieved by making suitable changes in the conditions of steam generation as discussed below:  Increasing boiler pressure: It has been observed that by increasing boiler pressure the cycle tends to rise and reaches a maximum value at a boiler pressure of about 166 bar.  Superheating: All the other factors remaining the same, if the steam is superheated before allowing it to expand the efficiency is increased.  Reducing condenser pressure: The thermal efficiency of the cycle is amply improved by reducing the condenser pressure. But the increase in efficiency is obtained at the increased cost of condensation pressure. 10

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 2 MATHEMATICAL CALCULATIONS Here we worked on this method/technique of pre-heating the feed water for reaching the aim,  By passing the feedwater through arrays of solar water heaters to raise the steam temperature. For backing up the aim and concreting it, we did a case study on a boiler section of a renowned fertilizer company. The difference here was that the steam was used in a reactor chamber for the manufacturing of Ammonia, rest all the other components were the same as a conventional power plant. All data were noted from the plant boiler section and the necessary charts available from the plant. Figure 1 shows the simplified layout of the plant, it is found in this model, that the feedwater temperature is around 190℃ before entering the boiler, and the exit conditions are 100 bar pressure and 500 ℃. The new approach or technique for the same process, is to introduce an array of solar heaters and necessary reservoirs as shown in figure 2 to increase the feed water temperature, and thus decreasing the amount of fuel required to be burnt to produce the steam. In this new model as we have introduced solar heating, we can get around 80-90℃ temperature difference through it, but neglecting the heat losses at different places like pumps, pipes, fittings etc. we calculate it down to at least 40-50℃. So, at the end we have our steam at 240℃ before entering the boiler. Figure 1. Conventional layout of plant Figure 2. Modified layout of plant According to the Bureau of Energy Efficiency, the Direct method to calculate the efficiency of the boiler is given as, ������ = (������ × (������������ − ������������)) × 100 (1) (������ × ������������������) Hg - Enthalpy of saturated steam in Kcal/kg Hf - Enthalpy of feedwater in Kcal/kg 11

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Parameters to be monitored for the calculation of boiler efficiency by direct method are:  Quantity of steam generated per hour (Q) in kg/hour  Quantity of fuel used per hour (q) in kg/hour  The working pressure (in kg/cm2) and superheat temperature (°C) if any  The temperature of feed water (°C)  Type of fuel and gross calorific value of the fuel (GCV) in kCal/kg of fuel Now according to the data available from the Boiler section of the plant we have:  RLNG (Re gasified LNG) = 5016 kg/hour or 5.106 TPH  Feed water temperature = 190.3 ℃  Feed water flow = 81950 kg/hour  Total steam produced = 80168 kg/hour (Urea plant) + 2690 kg/hour (FD fan turbine) + 5057 kg/hour (BFW pump turbine) (Note: The data was revised by a plant process engineer legally recruited by the plant management.). There- fore, calculating efficiency; ������ = (87.915 × (663.872 − 192.844)) × 100 = 80% (2) 5.106 × 10307.403 Now according to our aim, keeping the efficiency constant we calculate ‘q’ i.e., the Quantity of fuel used per hour, but in this case the feedwater is taken to around 240℃ against 190℃ in the 1St case. ������ = (87.915 × (663.872 − 247.826)) (3) q × 10307.403 (4) ∴ 0.8 = (87.915 × 416.046) q × 10307.403 Therefore, from Eq. (4) we get the value of quantity of fuel used as q= 4.435 TPH. It is clearly seen here that in the 1ST case we used 5.016 TPH and in the 2ND case we use 4.435 TPH for the same quantity of steam and efficiency. From calculation shown above, we save around 603.72 Kg of fuel, plus low carbon footprint. Figure 3 below shows the effect of varying feed water temperature to the amount of fuel required to be burnt. (Figure 3 shows the relation of feedwater temperature, enthalpy at that temp. and amount of fuel burnt) Figure 4 shows the enthalpy differences, the amount of heat to be given reduces from Q0(H2-H0) to Q1 (H2 – H1). Figure 3. Amount of fuel burnt v/s Feed water temperature 12

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Figure 4. Temperature vs Enthalpy 3 CONCLUSION With this analytical and case study, it is clearly seen that with certain takeable changes, here by increasing the feedwater temperature the fuel consumption and the amount of carbon footprint can be reduced to a good amount, furthermore with the quality of superheated steam produced, the turbine blades will have less wear and tear and would have a long life. REFERENCES [1] \"Key World Energy Statistics 2020,\" [Online]. Available: https://www.iea.org/reports/key-world-energy-statistics- 2020. [2] R. K. Rajput, A Textbook of Engineering Thermodynamics, Firewall Media, 2010. [3] \"Bureau of Energy Efficiency,\" [Online]. Available: https://beeindia.gov.in/. 13

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 FLOW VISUALIZATION OF FOOTBALLS TO ANALYZE ITS PERFORMANCE AND KNUCKLING EFFECT K. SRAVAN; SHAHISTHA; MENON RITHWIK; BABU SIDHARTH SCMS School of engineering and technology Vidyanagar, Palissery, Karukutty Eranakulam, Kerala, India ABSTRACT: The design of a football involves consideration of various aerodynamic parameters to optimize its flight characteristics such as surface roughness, number of panels, panel shapes, seam angle etc. The de- sign of football has evolved from the standard 32-panel to the 6 panel with different panel shapes. The prima- ry objective of this study is to determine the influence of design parameter- surface roughness, of selected and designed balls a smooth sphere, 32 panel football and FIFA 2014 football Brazuca on its aerodynamics evalu- ated by the flight characteristics such a drag force, drag coefficient and lift coefficient in CFD Analysis. The result of these effects with and without surface roughness’s are explained in the paper and are used to explain and understand the reasons behind the unusual phenomenon of knuckling effects of footballs. 1 INTRODUCTION When it comes about football matches, one of the most overlooked factors is the football itself. The most common exciting factor is that football has undergone many changes over the years. Excitement is building for fans across the globe with today’s match of the Fédération Internationale de Football Association (FIFA) World Cup tournament. Humans have been interested in aerodynamics and flying for thousands of years, While NASA is known for rocket science and airplanes; it also loves to solve more down-to-earth problems. These fans include NASA engineers, who used the lead-up to the tournament to test the aerodynamics. Alt- hough NASA is not in the business of designing or testing balls, they show interest in bringing up develop- ment in such a sport to provide an opportunity to explain the concepts of aerodynamics to students and indi- viduals by showing them they can relate to. These remarkable changes in the design parameters of football have made the researchers curious to study its effects on the aerodynamics [1]. To begin with, the work by Alam, Chowdary, Moria and Fuss [2] shows the study of aerodynamics of 32 panels and 14 panels using the setup of wind tunnel experiments plotting the drag force and coefficient considering the seam angle of the balls. Similarly, analysing of five non-spinning FIFA approved soccer balls in same setup and predicting its trajectories by Goff, Hobson, Asai and Hong [3] explained the knuckling effect with respect to Reynolds number and hydrodynamic boundary layers. Recent work by Hasan, Haider and Naimuddin [4] has conclud- ed that CFD analysis can be conveniently used in place of Experimental work and gave a whole initiative of completing the project using simulation software since the results and similar compared when done in a wind tunnel experiment [5]. In all these case studies, failed to consider the major design factors that depend on modern football design which would help in studying the unpredicted path of balls; understand the reasons that control the flight of the ball and improvement from the conventional 32 panel ball. This study focuses on simulation techniques to analyse flight and factors influencing it. The objective of this work tends to bring out the effects of important parameters, the surface roughness and number of panels that are considered which effectively brings out the currently derived football designs. The drag force and lift force of balls and smooth sphere with surface roughness under the knuckling velocity is used in comparison to explain the flight characteristics and to analyse the knuckling effect. 14

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 2 METHODOLOGY 2.1 Design The required models were designed in Autodesk Fusion 360 with desired dimensions and appearance. The Design of football changes in number, shape, surface roughness of the panels, all the footballs being used are given the properties of standard ball ‘size 5’ dimension- diameter 22cm, circumference 68cm. The first de- sign was a smooth sphere with white leather as material. The conventional 32 panel has a spherical truncated icosahedron and it contains 12 regular pentagons and 20 regular hexagons which are externally stitched. These panels are given the same synthetic white and black leather as the sphere. The first thermally bonded ball was the Teamgeist in 2006 FIFA with reduced no of panel of 14, then came the 2010 Jabulani which had 6 panels and ball Brazuca which is thermally bonded with reduced no. of panels of 8 which improves the consistency, was introduced in 2014 FIFA world cup by Adidas rectifying most of the aerodynamic prob- lems faced in Jabulani. 2.2 Meshing After modeling the footballs in Autodesk Fusion 360, the 3D model of football is imported to Ansys Work- bench Version 2019 R1. The fluid domain around the balls is modeled as enclosures and discretized in Ansys with tetrahedral elements. The shape of the enclosure is cylinder in order to resemble a wind tunnel and two side surfaces are named as inlet and outlet, the lateral surface as the wall of the enclosure keeping the ball in the middle from either side. The mesh generated in Ansys mesh editor has 110869 elements and 22094 nodes for the sphere, 51966 nodes and 267726 elements for the conventional football 2561245 elements and 579403 nodes for Brazuca. Figure 1: smooth sphere Figure 2: 32 panel football 15

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Figure 3: 2014 FIFA Brazuca 2.3 Simulation The flow is in-compressible and unsteady. The governing equations are conservation of mass and momentum equation and the selected model is K- Epsilon standard model and Realizable wall function settings for tur- bulent flow region. Discretization scheme: Momentum - A second order upwind scheme was used for acquir- ing the second-order accuracy, Pressure- second order and turbulent kinetic energy second order upwind. The velocity applied is 32m/s being the initial speed given for knuckling to happen. The considered surface roughness is 0.11, 0.55 and 2.75 at a height of 0.5mm.The governing equations: (1) Where ������ = density; t = time; v= velocity; ∇= Divergence. (2) (3) (4) Equations (2), (3) and (4) are x,y and z components of momentum equation respectively. 3 RESULT AND DISCUSSION When a smooth ball is struck over a speed of 70mph with little or no spin, the ball tends to move laterally as the drag coefficient drops and the lift coefficient slightly increases. As a result the ball gets unstable in mid- air and the trajectory of the ball becomes unpredictable even by the person hitting the ball. 16

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 3.1 Influence of number of panels in balls Figure 4: Cd vs. iterations The graph resulting from the CFD simulation of the three balls, smooth sphere, 32 panel football and brazuca of 8 panels after 150 iterations is shown. The x axis shows the number of iterations and the y axis shows the drag coefficient, Cd. The inlet condition is 32m/s which are the average speed of knuckling effect to take place (70mph). Since the first result is to analyze the aerodynamics of the ball is obtained without consider- ing the surface roughness, the number of panels gives major importance here. No external surface roughness is applied to the sphere, 32- panel ball and Brazuca in simulation to eliminate the additional influence of sur- face roughness. For the first little iteration the Cd values are abruptly high and then tend to decrease gradual- ly. From the 100th iteration and after the value converges and becomes constant throughout. For an ideal sphere the coefficient of drag is between 0.47 and 0.5. The value of Cd for smooth sphere is 0.5038, conven- tional football with 32 panels is 0.591 and brazuca with 8 panels is 0.533 were obtained from the analysis. The influence of this design parameter is negligible during laminar flow, and shows deviation once it reaches turbulence. From this graph, the ball with 32 panels has the highest drag coefficient followed by Brazuca and smooth sphere. This shows that an increase in no. of panels results in an increase of drag coefficient. The no of panels also includes the seam length so that, no. of panel is proportional to the seam length i.e, increase in drag coefficient is also depended upon the seam length. Lift acts perpendicular to the motion of the direction of the ball. It is a force on a soccer ball that can be used to loft or dive the ball that is it helps the striker to kick by giving an elevation. For an ideal sphere the lift coefficient is 0.25. In short drag is the property of an object which withholds in midair and lift is a property which allows an object to elevate from the ground and helps in its trajectory. Whenever drag decreases the effect of lift is compromised. 3.2 Influence of surface roughness on sphere Figure 5: Cd vs. velocity In the previous result it is found that in the case of the number of panels, the 32 panel football has greater value of drag coefficient and it justifies. But the 32 panel does not have surface roughness practically. In the past years the game football was much of a slower game so that surface roughness consideration was not an 17

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 important factor. After the 1990s the importance of the ball as such was looked upon and the first non 32 panel football was introduced in 2006. The evolution of football thus began, design the number of panels are reduced to optimise the design, to ease the manufacturing process and to bring consistency. In this analysis the surface roughness factors were 0.11, 0.55, and 2.75 applied on the periphery of a regular sphere. The roughness height was given as 0.5mm as the most common roughness dimples are of the same dimension. From the graph it is inferred that at the point of 32m/s, the Cd is 0.5289 for 0.11, 0.5498 for 0.55 and 0.6961 for 2.75. As the velocity increases over 50m/s, the Cd tends to increase. Smoother the sur- face less will be the drag and when surface gets rougher the drag increases and the effect of lift slightly de- creases. Due to these additional dimples over the surface over smooth sphere the air flow is turbulent. The interaction between surfaces irregularities with the turbulent flow creates eddies in the valleys of the dim- ples. As a result the drag on the ball is increased allowing it to stay in air for a longer time thus reducing the effects of lift. The surface roughness can also be a problem for the flight of the ball as too much drag results in more lift force for the ball to elevate. Thus the surface roughness factor should be in a balance that the natural movement of football does not get affected. The knuckleball is when the ball does not spin as it flies through the air. Spin is what gives ball stability as it moves, and without it your shot will snake through the air, changing directions suddenly and making it nearly impossible for a keeper to predict. The knuckleball is when the ball does not spin as it flies through the air at a certain velocity from 70mph to 80 mph. Spin is what gives a ball stability as it moves, and with- out it your shot will snake through the air, changing directions suddenly and making it nearly impossible for a keeper to predict. Knuckling effect increases whenever there is less no. of panels and the given surface roughness is not appropriate enough to generate drag thus bringing a negative influence to the aerodynamics of the ball, the drag reduces drastically and the effect of lift acts biased creating an imbalance. Due to this ef- fect the trajectory cannot be predicted even by the person kicking the ball and creates an uncertainty giving an unfair advantage over one person. The above results show that application of surface roughness on foot- balls having lesser no. of panels has helped in the reduction of knuckling effect. In graph fig.5, it is seen that the drag coefficient almost remains constant when roughness is given, between the 32m/s to 35m/s which is the velocity the ball travels during knuckling effect. Thus we can conclude that the ball Brazuca with less no. of panels with surface roughness act as a perfect sphere with optimum drag and lift without the knuckling giving a predictable trajectory when compared. 4 CONCLUSION In this study, the influence of surface roughness and number of panels of the footballs on the aerodynamics and flight characteristics were evaluated by numerical simulation using Ansys Fluent on three balls, a smooth sphere, 32 panel ball and Brazuca which has different number of panels, panel shapes, seam length and surface roughness. The results are compared when a starting velocity of knuckling effect that is 32m/s is given. The first result where the CFD of the sphere, 32 and Brazuca is analyzed without surface roughness indicates the importance of the number of panels. When the number of panels increases drag force and lift increases such that 32 panels show the highest drag when compared but in modern design when panels are reduced it is necessary to add surface roughness. Increase in surface roughness increases the drag coefficient. The importance of surface roughness is to eliminate the knuckling effect by keeping the ball and velocities in a turbulent region. Using surface roughness beyond a certain value will increase the lift making it difficult for the striker to kick the ball. The 32 panel has more panels than Brazuca but without surface roughness in the 32 panel practically, the purpose becomes invalid. Brazuca shows the effects as that of a perfect sphere when there is surface roughness on less number of panels increasing the drag force with perfect lift. The formation of eddies on the rough surface around the periphery of the football increased the drag that eventu- ally stabilized the football. With the above conclusions knuckling effect is explained. The official football used in the tournament, Jabulani, had some flaws and earned a lot of criticism due to the geometry and the seam of the ball; it had a relatively high drag coefficient due to knuckling effect. Thus the ball was stable in midair while it was struck to high speeds. Therefore the design of Brazuca formed in the consecutive world cup has rectified all these problems with increased panels from 6 to 8 and increased surface roughness giving it a predictable trajectory. In future footballs designs may also come across such problems where it can be solved by varying the surface friction factor along with reduction or increase in panels. 18

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 REFERENCES [1] A. Firoz, C. Harun, S. Mark, W. Zilong and Y. Jie, \"Effects of surface structure on soccer ball aerodynamics,\" in International Sports Engineering Association (ISEA), 2012. [2] A. Firoz, C. Harun, M. Hazim and F. Franz, \"A Comparative Study of Football Aerodynamics,\" in International Sports Engineering Association (ISEA), 2010. [3] G. John, H. Sungchan and A. Takeshi, \"Influence of Surface Properties on Soccer Ball Trajectories,\" in International Sports Engineering Association (ISEA), 2020. [4] H. Suhaib, H. Talha, H. Sayyed and Naimuddin, \"Experimental analysis of velocity distribution over a sphere placed in wind tunnel and its comparison by CFD,\" International Journal of Scientific & Engineering Research, vol. 8, no. 7, 2017. [5] G. John, H. Chad, A. Takeshi and H. Sungchan, \"Wind-tunnel Experiments and Trajectory Analyses for Five Nonspinning Soccer Balls,\" in International Sports Engineering Association (ISEA), 2016. 19

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 CONDENSER JACKET BATTULA SUNIL, PEYYALA ANUSHA, MOVVA NAGA SWAPNA SRI, BAKKA SANTHOSH, KUCHIPUDI JAYANTH, AVUTAPALLI DINESH Prasad V Potluri Siddhartha Institute of Technology, Vijayawada, Andhra Pradesh, India ABSTRACT: The role of a Condenser jacket is to cool down the hot air liberating out of condenser unit of an air conditioner. The mud plates inserted in the aluminium casing absorbs the hot air with help of water. Hence the hot air turns cold. Hence this condenser jacket reduces global warming. 1 INTRODUCTION An Air Conditioner in a room liberates hot air from a given space which leads to develop harmful gases that are causing major effect to environment. Our aim is to develop the condenser jacket at the compressor which leads to decrease in hot air and harmful gas content to environment. We used an evaporative cooling [1] technique to decrease the temperature of air which is the outlet of condenser unit, the construction of the condenser jacket is made in such a way that it perform evaporative cooling so that the hot air which will pass through this condenser jacket will be cooled. 2 EXPERIMENTAL SETUP 2.1 COMPONENTS The below are the main components of the Condenser jacket 2.1.1 CLAY GLASS Clay glass is the most important component in condenser jacket,why because the difference of temperature is takes place mainly based on this component.The composition of the clay glass is same as the composition of the normal clay.the dimensions of the clay glass are top diameter is 7.5cm and the bottom diameter is 4.7cm.Design of the clay glass is done by using solid works software the design of the clay glass with different views is given below. Figure:-1(front view of the clay glass). Figure:-2(top view of the clay glass). 2.1.2 ALUMINIUM MESH Aluminium Mesh is the second important component in the condenser jacket aluminium mesh is the component which holds the clay glass.the aluminium mesh is designed in such a way that the clay glasses are placed in the mesh with out any obstruction and tight.the mesh consists of rhombus shaped hollows in which 20

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 the clay glasses are placed.the dimensions of the rhombus shaped hollows are Diagonal:-8.5cm and the length of each side is 6cm.and the dimensions of the whole aluminum mesh are length:-80.5cm and the height:-60.2cm.the design of the aluminium mesh is done by using solid works software the design of aluminium mesh with different views is given below Figure 3: Front view of Aluminium mesh Figure 4: Side view of the aluminium mesh 2.1.3 ALUMINIUM CASING Aluminium casing is to hold the aluminium mesh the aluminium casing is acts as the frame in condenser jacket which holds the aluminium mesh.and also it is easy to fix the condenser jacket to the outdoor unit of air conditioner without this aluminium casing we cannot fix the condenser jacket to the outdoor unit of air conditioner.the dimensions of the aluminium casing are length:-83cm with height:-62.7cm and the thickness of 2.5cm.the design of the aluminium casing is done by using solid works software the design of aluminium casing with different views is given below Figure 5: Front view of aluminium casing Figure 6: Side view of the aluminium casing 2.1.4 DRY GRASS Dry grass is the another component in the condenser unit which helps to covert the temperature of the hot air from the condenser.the grass is kept around the clay glass to capture the hot air which comes out from the outdoor unit of air conditioner.the picture of dry grass is given below Figure 7: Dry grass 21

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 2.2 ENTIRE SETUP The condenser jacket entire setup is contains of above components. The each component has its own importance to get the perfect output. The construction of the condenser jacket is given below. 3 CONSTRUCTON The main important component in the condenser jacket is as mentioned above it is clay glass.the clay glass is fixed on the aluminium mesh in those rhombus shaped hollows the clay glasses are kept in those hollows in a pattern one after another alternatively leaving spaces in between.after completing the arrangement of clay glass in aluminium mesh.the next immediate work is to incorporate the dry grass in between the left spaces and around the clay glasses.then this total arrangement aluminium mesh is placed in the aluminium casing and after the entire setup is fixed to outdoor unit of the air conditioner.the prototype of the condenser jacket is given below Figure 8: Condenser jacket 4 WORKING The condenser jacket is works under the basic principle of evaporative cooling, [2] [3]when the condenser jacket is attached to the outdoor unit we make sure that the outlet water of the condenser unit is flowed on the condenser jacket so that the clay glass and dry grass will become wet so that when the hot air comes out from the outdoor unit and it goes through the condenser jacket due to this wet clay glass the hot air converts into cool air.that is how the condenser jacket works. Figure 8: Basic VCR System with Condenser Jacket The above Figure:8 gives the detailing of the VCR system after installing the Condenser Jacket in front of the Condenser. So that the hot air released from the condenser will not directly enters to atmosphere ,Thus the hot air passes through the condenser jacket will turns to cool this helps to decrease the global warming. 22

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 5 EXPERIMENTATION We took the readings of the condenser outlet temperature and condenser jacket out let temperature also the atmosphere temperature using digital thermometer. We took the readings of 3 days respectively. The readings are given below in the Table 1. Table 1: EXPERIMENTATION VALUES CONDENSER OUTLET CONDENSER JACKET S.NO. ATMOSPHERE TEMPERATURE OUTLET TEMERATURE (IN DEGREES CELSIUS) (IN DEGREES CELSIUS) TEMPERATURE (IN DEGREES CELSIUS) 1 35.3 45.1 41.2 2 35.8 44.5 40.5 3 36.9 45.1 40.1 AVG:-44.9 AVG:-40.6 GRAPH BETWEEN CONDENSER JACKET OUTLET TEMPERATURE AND CONDENSER OUTLET TEMPERATURE CONDENSER OUTLET TEMPERATURE (IN DEGRESS CELSIUS) 46 40.2 40.4 40.6 40.8 41 41.2 45 44 43 42 41 40 39 40 CONDENSER JACKET OUTLET TEMPERATURE (IN DEGREES CELSIUS) Figure 9: Graph between condenser jacket outlet temperature and condenser outlet temperature 6 RESULT The result and discussion section the readings or values which were noted while making the required trial about the functioning and doing the performance check of the condenser jacket. The temperature of the air released from the condenser was taken using the digital thermometer and noted down for further references. The difference between the condenser outlet temperature and the condenser jacket outlet temperature is around 4 to 5 degree centigrade. 23

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 7 CONCULSIONS The main use of the condenser jacket is decreasing of global warming. The global warming is occur due to the greenhouse gases, pollution and many but all these greenhouse gases and pollution makes the globe warm the problem is globe getting warmed the outdoor unit of the air conditioner releases the hot air which makes the globe warm or which helps to increase in global warming. So if we use the condenser jacket it helps to covert the hot air of the outdoor unit of AC into cold air, so that we can decrease the global warming a bit. REFERENCE [1] O. Amer, R. Boukhanouf and H. Ibrahim, \"A Review of Evaporative Cooling Technologies,\" International Journal of Environmental Science and Development, vol. 6, no. 2. [2] F. Bdollahi, S. A. Hashemifard, A. Khosravi and T. Matsuura, \"Heat and mass transfer modeling of an energy efficient Hybrid Membrane-Based Air Conditioning System for humid climates,\" Journal of Membrane Science, vol. 625, pp. 119-179. [3] T. L. Bergman, \"Active daytime radiative cooling using spectrally selective surfaces for air conditioning and refrigeration systems,\" Solar Energy, vol. 174, pp. 16-23. [4] J. Soheil, D. Julian F, L. Mostafa, Y. Zhiyin, P. Jean-Pierre, L. Chris A and J. Jisjoe Thalackottore, \"A review of evaporative cooling system concepts for engine thermal management in motor vehicles,\" Proc IMechE Part D:J Automobile Engineering, vol. 231, no. 8, p. 1126–1143. [5] B. Qinghan, \"Waste heat: the dominating root cause of current global warming,\" Bian Environ Syst Res, vol. 9, no. 8. 24

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 DESIGN AND EXPERIMENTATION OF ARROW THROWING MECHANISM FOR ROBOCON 2021 SHETH KUSHAL, SHEKHDA DHRUMIL, VASJARIYA ABHAY, CHAUHAN MIHIR, MECWAN AKASH Institute of Technology, Nirma University, S G Highway, Ahmedabad-382481. Gujarat, INDIA ABSTRACT: In an ideal Projectile motion, the parameters of the projectile like Range, Maximum Height, Time of flight and path of the projectile can be known by its conventional equations. But they are calculated without considering the air drag and the losses of the systems. In the physical world, the systems are not in ideal con- dition; the air drag, the environmental conditions and the shape of the projectile affect the motion. This article mainly focuses on the computation of the projectile parameters of the distributed mass object (arrow) consid- ering the surrounding conditions and the analysis of the mechanism which is pneumatically actuated and can be used for shooting, rather than the conventional bow and arrow mechanism. This mechanism is anchored to the robot for ABU Robocon 2021 competition. 1 INTRODUCTION The conventional shooting mechanism (bow and arrow type) works on the principle of elastic energy [1]. An elastic string is stretched to store energy. The string is then released which converts the elastic energy into kinetic energy. Modern bows have become much more advanced. It uses a complex cam mechanism to store elastic energy and shoot arrows. However, the mechanism in context to this paper does not use any elastic element to store energy to shoot an arrow. The mechanism designed uses a pneumatic cylinder to shoot an arrow. A conventional design of an arrow includes a head, a shaft and plume wings [2]. An arrow is a distrib- uted mass object. Hence, there will be some unbalanced forces due to which the projectile parameters obtained from the conventional equations would not be accurate. This has to be taken into consideration. Also, there will be air drag which has to be considered [3]. For the Robocon competition [4], due to dimension constraints, the pneumatic actuator has been used. This mechanism provides both the required range as well as reduced dimensions. 2 DESIGN OF THE MECHANISM: The proposed throwing mechanism consists of a Class 3 lever grounded to a frame at the fulcrum point. A pneumatic cylinder is connected to this lever using a revolute joint. The effort to the lever is provided by this cylinder. The other end of the cylinder is grounded to the frame in such manner that it converts the maximum force of the cylinder in the rotation of the lever. On the free end of the lever, a pneumatically actuated gripper is mounted. The design of this gripper consists of a combination of two slider-crank mechanisms actuated by a cylinder. It helps in gripping and releasing the arrow as and when required. The change in angular position of the lever can be determined using a rotary encoder attached to the fulcrum of the lever. 2.1 Synthesis In conventional bow and arrow mechanisms, an elastic material is used to store the energy [1]. This energy in return is converted to translational motion with a high velocity. This momentum is then transferred to the arrow for shooting [5]. The only limitation with this mechanism is that the material used to store the energy loses its elasticity with time. To overcome this, a lever, actuated by a pneumatic cylinder, must be used to shoot the arrow. The arrow height and range can be controlled using pressure and the angle of release. An encoder is 25

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 used at the fulcrum point to measure the angle rotated by the lever. Pneumatic cylinders provide a high mo- mentum to the arrow to gain better range. Figure 1: CAD Model of Throwing mechanism 2.2 Kinematic analysis From the standard equation, (1) ������������ = ������ × ������ (2) Where, I = moment of inertia of throwing arm α= angular acceleration of the throwing arm F = force acting on the lever which will cause its motion a = radius in which arrow will travel while actuation of lever ∴ ������ = ������������ Also, ������ = ������ ������������ ∴ ������ = (������������) ������ (������������������������) ������ ������������ Figure 2: Labelled Throwing Diagram From Figure 2, it can be seen that only the cosine component of the force applied by the piston will contribute to the projectile motion of the arrow ������������������������������������������������������������ (������ + ������) = (������������) ������ (������������������������) (3) From Figure 2, 26

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 ������������������������ = ������������������������������ −������������������������������−������ and ������ = ������������������⁻¹ (������������������������������������������������+−������������������������) (4) ������������������������������ Substituting equation (4) in (3), ∫ ������������������������������������������������������������ (������ + ������������������−1 (������������������������������������������������+−������������������������)) ������������ = ∫ (������������) ������������������ (5) As this is a non-linear algebraic expression, the solution of the integration is complex. Thus, applying Simp- son’s one-third rule [6], ������ = {���3��������������� ∗ ������������������������������������������ [������������������(������������������������(������2−������) + ������������������(������ + ������������������������(������������������ ������−������������ )) + 4������������������(���2��� + ������������������������(���������������������������������������2���2������−+������������������������ )))]}1/2 ������ +������������ ������������������ (6) Substituting the angular velocity formula ������ = ������ in equation (6), ������ ������ = {������3������������3 ∗ ������������������������������������������ [������������������(������������������������(������2−������) + ������������������(������ + ������������������������(������������������ ������−������������ )) + 4������������������(���2��� + ������������������������(������������������ ���2���−������������ ))]}1/2 ������ +������������ ������ +������������ ������������������ ������������������ 2 (7) This is an ideal condition which does not consider losses. But practically, the system consists of frictional and other type of losses which cannot be neglected. Thus, multiplying equation (7) by a factor ������, the velocity obtained is ������ = ������{������3������������3 ∗ ������������������������������������������ [������������������(������������������������(������2−������) + ������������������(������ + ������������������������(������������������ ������−������������ )) + 4������������������(���2��� + ������������������������(������������������ ���2���−������������ ))]}1/2 ������ +������������ ������ +������������ ������������������ ������������������ 2 (8) 3 PROJECTILE MOTION Generally, in the study of projectile motion, it is assumed that effects of air-resistance are negligible. But air resistance (often called air drag, or simply drag) has a major effect on the motion of every object. ������������ ≠ ������������������������������������������������ Here, a fluid resistance force affects the trajectory of a projectile motion. The drag force acting on an object is [7], Fdrag = 1 ⍴v²Cd A (9) 2 Where, ������ = ������������������������������������������ ������������ ������������������, ������ = ������������������������������������������������ ������������ ������ℎ������ ������������������������, ������������ = ������������������������ ������������������������������������������������������������������, ������ = ������������������������������ − ������������������������������������������������������ ������������������������ This drag force is always in the opposite direction to velocity. It’s not difficult to include the force of air resistance in the equations for a projectile, but solving them for the position and velocity as functions of time or the trajectory of the path can get quite complex. But these calculations can be easily performed by Euler's numerical method [8]. The net force acting in the X – direction and Y – direction are, ∑ ������������ = −������������������������������ = ������������������ ∴ ������������������ = − 1 ⍴���������2��������� ������������ ������ 2 ∴ ������������ = − 1 ⍴���������2��������� ������������������ (10) 2������ ∑ ������������ = −������������������������������ − ������������ = ������������������ ∴ ������������������ = − 1 ⍴���������2��������� ������������ ������ − ������������ 2 27

∴ ������������ = − 1 ⍴���������2��������� ������������ ������ − ������ Proceedings of International e-Conference on 2������ Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 (11) Now that the acceleration in the x-direction and y-direction is for the first 1/100th second, it can be assumed constant. The final velocity at the end of 1/100th second will be, ������������������ = ������������������ + ������������������������ (12) ������������������ = ������������������ + ������������������������ (13) Displacement at the end of 1/100th second will be, ∴ ������������ = ������������ + ������������������ ������������ + 1 ������������ ������������2 (14) 2 (15) ∴ ������������ = ������������ + ������������������������������ + 1 ������������������������2 2 As the acceleration, velocity and position in the x-direction and y-direction at the end of 1/100th second have been figured out, the data can be used as the initial condition to calculate the further values for the next hun- dredth second in the respective directions. This is tedious work and thus the computational power can be used to solve it. 4 EXPERIMENTATION Materials used in this experiment were a frame made up of Mild steel, a throwing lever of a square cross- section of dimensions 15*15*1 mm made of Mild steel, a pneumatic cylinder of specifications 32*125 mm to actuate the throwing lever, a pneumatic cylinder of specifications 16*25 mm to actuate the gripper assembly, Stainless steel Shaft of diameter 12 mm for the fulcrum point, a 10 bit-Encoder attached at the fulcrum point for the measurement of the angle of the throwing lever. As per the requirements, the mechanism height is fixed in such a manner that the arrow release point is 1.40m above the ground. The rotating lever has a length of 735 mm. The moment of inertia ������ for the throwing lever along with the arrow is found out to be ������������������������������������ = ������������������������ + ������������������������������������������������+������������������������������ (16) = 0.066 + 0.544 ������������������������������������ = 0.61 ������������������2 Here, for the practical application, the air pressure provided is 4.0 bar and the cylinder used is of 32mm bore diameter. The experimental Force of the piston will be [9] [10], ������������������������������������������ = ������������������ ������������������������������������������������ × ������������������������������ ������������������������������������������������������ ������������������������ ������������������������������������������ = 321.53 ������ (17) theTgarkipinpgerprrealcetaicsaelsdtahteaa���r���r=ow���4���a, sa = 160, b = 280 and d = 125 with 80% efficiency, the velocity obtained when per equation (5) is ������ = 12.84 ������/������ (18) Now this will be the initial velocity for the arrow to follow a projectile path. According to equation (7), the initial drag force calculated for this arrow is [3], ������������������������������ = 1⁄2 ⍴������²������������������ = 0.0054 ������ For the observed and calculated data, a computation can be done using excel to find the range of the arrow. 5 RESULTS AND DISCUSSION Figure 44 shows the practical range found with the help of tracker while Figure 3 shows the theoretically calculated range for the arrow. The range 28

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 obtained for the given value of pressure and release angle is approximately 10.73m. The calculated range from the graph is 10.83m. Thus, the value calculated with the help of Euler’s Numerical method, considering the physical conditions and air drag, matches the practically observed values. Figure 3: Practical Projectile Range Figure 4: Theoretical Projectile Range Figure 5: A Snapshot from Tracker 6 CONCLUSIONS A physical system is never ideal and hence the theoretical estimations might not always match the practical results. The theoretical data consists of assumptions and neglections. The arrow throwing mechanism was mounted on the robot and the range was found out using calculations to throw the arrow into the given pot. While performing an experiment physically, the presumptions could not be neglected. This was proved in the experiment where the surrounding environment, the air drag, the efficiency and the losses of the system were acknowledged. REFERENCES [1] M. Ohara, N. Kawasaki, J. Nakahama, Y. Takada and H. Watanabe, \"Development of an Archery Robot for the Selection of Arrows,\" in The 13th Conference of the International Sports Engineering Association, 2020. [2] W. Yong, Z. Ahmad and I. Mat Sahat, \"Development and analysis of arrow for archery,\" Journal of Engineering and Applied Sciences, vol. 11, pp. 7443-7450. [3] S. Buček, \"FALLING OBJECTS AND PROJECTILE MOTION WITH REGARD TO THE AIR RE-SISTANCE,\" in International Conference on Education and New Learning Technologies, Barcelona, Spain, 2016. [4] \"ABU Robocon,\" [Online]. Available: https://en.wikipedia.org/wiki/ABU_Robocon. [5] B. Kooi, \"On the mechanics of the bow and arrow,\" Journal of Engineering Mathematics, vol. 15, pp. 119-145, 1981. [6] a. k. Singh and G. Thorpe, \"Simpson’s 1/3-rule of integration for unequal divisions of integration domain,\" Journal of Concrete and Applicable Mathematics, 2003. [7] S. Maxemow, \"That's a Drag: The Effects of Drag Forces,\" Undergraduate Journal of Mathematical Model-ing: One + Two, vol. 2, no. 1, 2009. [8] M. Nurujjaman, \"Enhanced Euler's Method to Solve First Order Ordinary Differential Equations with Better Accuracy,\" Journal of Engineering Mathematics & Statastics, vol. 4, no. 1, pp. 1 - 13, 2020. [9] M. Jiménez, E. Kurmyshev and C. Castaneda, \"Experimental Study of Double-Acting Pneumatic Cylinder,\" Experimental Techniques, vol. 44, pp. 355-367, 2020. 29

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 [10] A. Lara-L´opez, J. P´erez-Meneses, J. Col´ın-Venegas, E. Aguilera-G´omez and J. Cervantes-S´anchez, \"Dynamic analy-sis of pneu-matically actuated mechanisms,\" Ingeniería Mecánica Tecnología y Desarrollo, vol. 3, no. 4, pp. 123-134, 2010. 30

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 SIMPLIFICATION OF BEARING FAULT DIAGNOSIS PROCEDURE USING MATLAB APP DESIGNER TOOL RAMCHANDANI ROHIT; PATEL DHAVAL; BHOJAWALA VIPUL Institute of technology, Nirma University, Ahmedabad (382481), Gujarat, India. ABSTRACT: Rolling element bearings tend to propagate continuous vibration signals while its operation. These signals could be captured and analyse to find out the actual condition of the bearing. Once a fault is produced in any bearing component, it tends to generate larger amplitude signals at a regular frequency, due to continuous impact with roller elements. These signals are generally modulated due to various high frequency signals present while rotation of the bearing. Hence demodulation of these signals is carried out with the help of enveloping techniques like Hilbert transform. Frequency of fault extracted after enveloping is compared with the rotation frequency of individual components to conclude fault in any particular bearing component. To make the entire process convenient MATLAB App Designer is used to analyse and display the condition of the bearing. The MATLAB App Designer tool takes bearing parameters and vibration data as input, providing statistical parameters and fault in bearing as an output. 1 INTRODUCTION Rolling element bearings are an integral part of any machinery and hence it becomes very important to continuously diagnose their condition for any seamless production. The main purpose of the bearing is to support the shaft load and allow smooth and high rotational speed. With the continuous rotary operation, several types of defects like insufficient lubrication, variation in shaft load, contamination, scratches, etc [1] may occur. These type of defects established with time causes an increase in vibration level of the bearing. These periodic vibrations may result in fatigue failure of the bearing, which must be avoided by predetermining the fault in bearing. Many methods like vibration, acoustic, temperature measurement, etc. [2] are used widely for fault diagnosis of bearings, but the main focus here is to develop a GUI based tool using MATLAB App Designer for analysis using vibration data. Generally, vibration accelerometers are used for capturing vibration signals from a bearing [3] and stored with the help of a data logger. Vibration data from the data logger could be extracted as raw acceleration versus time data. This raw data need to be processed with demodulation and FFT (Fast Fourier Transform) to detect the actual fault in a bearing. To make this entire process simpler and instantaneous a MATLAB App Designer is used here. 2 THEORY There are four main components in a roller bearing – Inner Race, Outer Race, Roller and Cage. In case of a fault in any of these, variation in the vibration signal is evident. In case of a fault in bearing, Low frequency peaks are usually generated due to the periodic impact of rolling elements while rotation. Each component has its individual rotational frequency about a point which makes it easy for us to detect the faulty components. These rotation frequencies of inner and outer races are defined as Ball Pass Frequency Outer-race (BPFO) and Ball Pass Frequency Inner-race (BPFI) which will be discussed ahead. The variations in vibration data can be analysed in both time domain and frequency domain to detect the cause of failure. In the current work, the analysis in both of these domains is performed and an attempt is made to automate the analysis with the MATLAB App Designer. 2.1 Time domain analysis Time domain analysis is the simplest way of visualizing signals with time as an independent variable and amplitude as a dependent variable. If there is a presence of a defect in the bearing, the impact of defects with bearing race and rollers cause variation in vibration data. By computing various statistical parameters from the 31

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 raw transducer data, it can be analysed if they are within safe operating range or not. Hence, time domain analysis mainly works on the interpretation and comparison of statistical parameters. But as a disadvantage, these parameters could not identify the severity of the fault and the component where the fault has occurred. It can only be identified whether the bearing is healthy or faulty by comparing these parameters with the threshold range. There are many such parameters [4] like mean, maximum, root mean square (RMS), standard deviation, variance, crest factor, clearance factor, impulse factor, shape factor, kurtosis, skewness, upper and lower bound that are used to evaluate the type of vibration from the bearing. 2.2 Frequency domain analysis Time domain analysis has a limitation to find the faulty component in the bearing and hence frequency domain analysis is performed. Fourier transform is a widely adopted technique to convert the time domain into the frequency domain. With the help of FFT all the individual frequency signals present in the original raw signal can be easily distinguished with each other [5]. The extracted peak frequency after FFT can be used to find the type of fault in the bearing by interpreting the cause of the peak. In the current work, the aim is to find the frequency corresponding to the fault in individual components, hence ball pass frequency becomes important for the present analysis. 2.3 Ball pass frequency All the bearing components have a particular frequency at which the number of rotation events occurs continuously. These frequencies are denoted as BPFO, which denotes the frequency of the balls passing through a particular point of the outer race, in a complete shaft rotation. Similarly, BPFI denotes the frequency of the balls passing through a particular point of the inner race, in a complete shaft rotation [6]. For balls and cage, it is denoted as Ball Spin Frequency (BSF) and Fundamental Train Frequency (FTF). The equations for the BPFO and BPFI are mentioned below in Eqs. (1) and (2): ������������������������ = ������������ × ������������ × [1 + (������������������������) × cos ������] (1) 2 (2) ������������������������ = ������������ × ������������ × [1 + (������������������������) × cos ������] 2 Where, fs = Sampling frequency, Nb = No. of Roller elements, Bd = Ball Diameter, Pd = Pitch Diameter, ������ = Bearing Contact Angle. If a crack or groove has occurred in the bearing race, roller elements continuously pass through this crack and generate a particular vibration frequency as shown in Fig.1. These vibration frequency corresponding to the frequency of balls hitting the defect is nothing but the ball pass frequency. Hence, if the fault vibration frequency matches with BPFO, it can be concluded that the fault is on the outer race. Similarly, if it matches with BPFI, it is evident that fault is on the inner race. But the main challenge here is to extract the actual fault signal from bearing raw vibration signal which is discussed further. Figure 1. Fault on the outer race of bearing 32

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 3 METHODOLOGY There is variation in the continuous radial load along the surface of bearing, scratches and waviness on the bearing surface. Due to this the amplitude modulated signal obtained after FFT is a combination of high frequency carrier signal and low frequency main signal. The main aim is to find the low frequency main signal from the modulated signal and the technique used for this is called demodulation [7]. Generally, demodulation is done by two techniques: i. Using Low pass filters to extract the low frequency signals in a specific range. ii. Signal Enveloping By Hilbert transform Here we will use the signal enveloping technique by applying Hilbert Transform on the raw signal to extract low frequency main signal [8]. Hilbert Transform simply works on the idea of phase shifting of the signal. Here the real signal ������(������) is converted into an analytical signal which is a complex signal denotes as : ������(������) + ������������{������(������)}, where H{x(t)} is Hilbert transform function denoted in Eq. 3. −������������ ������������ ������ > 0 (3) ������(������) = { 0 ������������ ������ = 0 ������������ ������������ ������ < 0 Enveloping is the square of analytical signals which will intensify the harmonic signals and reduces the amplitude of random signals. These low frequency enveloped signals are the main fault signals and FFT is performed to find the frequency of vibration. Comparing the frequency of vibration with rotational frequency BPFO and BPFI, fault in the component can be detected. 3.1 MATLAB App Designer The main aim is to perform the entire procedure mentioned above just with the input of bearing vibration time domain data and required geometrical parameters of bearing. All the operations will be automatically performed on input time domain data to display the condition of bearing – healthy, fault in Inner Race or fault in the outer race. Furthermore, all the necessary statistical parameters mentioned above can be evaluated within the MATLAB App Designer. The procedure to use the MATLAB App Designer is as follows: STEP 1: Enter the RPM of testing setup and required bearing parameters available from catalogue. STEP 2: Click on ‘CALCULATE’ to compute the value of BPFO and BPFI STEP 3: Upload your vibration data “.xls file” having amplitude and time data of transducer STEP 4: After uploading the excel file, click on ‘Plot & Evaluate’. STEP 5: Save or note the enveloped FFT signal waveform & result Displayed. STEP 6: Select ‘TAB 2’ from the top left corner and note all the statistical parameters for predicting the condition of the bearing by comparing with threshold values. Refer to Fig. 3,4 and 5 to understand the above steps. 33

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Figure 2. GUI developed in MATLAB App Designer Figure 3. Enveloped signal Figure 4. GUI for the statistical parameter 34

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 4 RESULT AND DISCUSSION Fig. 3 indicates the peak amplitude corresponds to the value of BPFO which is 90Hz. Similarly any kind of outer race and inner race faults are detected and result is displayed as in Fig. 2. Experiments were carried out for various defect and defect-free vibration data and the outputs were tested successfully. Fig. 4 indicates all the necessary Time domain frequency signals useful to indicate the condition of the bearing. For example, the value of Kurtosis exceeding 3 indicates faulty condition of the bearing as indicated in Fig. 4 which is 6.918. Similarly, all the necessary parameters could be compared with the threshold value to detect the presence of fault in the bearing. 5 CONCLUSIONS In this paper, an attempt is made to contribute towards a simpler and efficient way of bearing fault diagnosis by providing all functions in a MATLAB APP. Analysis of both Time and Frequency domain was implemented in the MATLAB app. Statistical parameters for Time domain analysis and enveloped FFT for Frequency domain analysis was performed . The APP was tested for all three types of bearings – Fault in Inner race, Fault in Outer race and Healthy Bearing with the experimental vibration data. The APP gave accurate results for three types of data and can be utilized for automation purposes and continuous monitoring of roller element bearing. REFERENCES [1] Wysoclci, A & Feest, B. 1997. Bearing failure: causes and cures. EC and M: Electrical Construction and Maintenance 96. [2] Nabhan, A ; Ghazaly, N ; Samy, A ; Mousa, M.O. 2015 . Bearing Fault Detection Techniques - A Review. ResearchGate. [3] Mohanty,A . Machine Condition Monitoring. [4] Shrivastava,A & Wadhwani,S . 2013. Development of Fault Detection System for Ball Bearing of Induction Motor Using Vibration Signals. International Journal of Scientific Reasearch 2. [5] Rai, V. K & Mohanty, A. R . 2007 . Bearing fault diagnosis using FFT of intrinsic mode functions in Hilbert–Huang transform . Mechanical Systems and Signal Processing - Elsevier 21 : 2607-2615. [6] Saruhan, H ; Saridemir, S ; Çiçek, A ; Uygur, I. 2014. Vibration analysis of rolling element bearings defects . Journal of Applied Research and Technology 12 : 384-395. [7] Sheen, Y.T . 2007 . An analysis method for the vibration signal with amplitude modulation in a bearing system . Journal of Sound and Vibration 303 : 538-552 . [8] Kim, S ; An, D ; Choi, J. H. 2020. Diagnostics 101: A tutorial for fault diagnostics of rolling element bearing using envelope analysis in MATLAB. Applied Sciences (Switzerland) 10 : 3-7. 35

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 DETAILED DESIGN OF A QUADRUPED ROBOT BASED ON 5-BAR LINKAGE LEG SHEKHDA DHRUMIL, CHAUHAN MIHIR, SHETH KUSHAL, BODA JIGAR, GAJARA PARTH Institute of Technology, Nirma University, S G Highway, Ahmedabad-382481, Gujarat, INDIA ABSTRACT: This paper focuses on the design consideration of a quadruped robot. It includes the design basics, manufacturing methods, calculations of the inverse kinematics of a leg, basic walking algorithm, and its gait pattern. The proposed robot consists of four 2-DOF legs, actuated using servo motors. It can transverse on different terrains and carry additional payloads including sensors and other electronics. The main goal of this paper is to present an innovative, modular, and inexpensive design of a four-legged robot for locomotion re- search purposes. The paper presents robot design, control system, inverse kinematics, and the experimental data to compare the results. 1 INTRODUCTION Nowadays, mobile robots are highly trending in the area of research in the Robotics field. The quadruped robots can transverse on all types of terrain where wheeled robots face difficulties to travel. These robots have more functionality and are time efficient in task execution. From many years efforts have been made to build a walking robot. The first model of such functioning robot was built in 1870 [1]. Then after, many prototypes were built to test but they either failed in terrain constraints or did not achieve any feasible walking pattern and hence, lost balance [2]. McGhee and Frank [3] produced the first robot to move autonomously through computer control and electric propulsion in 1966. This robot was controlled by a computer and solved kine- matic equations to walk forward while maintaining balance. Since then, many such robots have been built with different abilities such as running [4], jumping [5] and climbing or walking [6] on a rough terrain. 2 DESIGN OF ROBOT 2.1 Synthesis: type of mechanism and length Conventionally, 2-link for 4 legs, consisting of 2 revolute joints actuated by 2 motors [2], is designed. In this straightforward design, the load acting on the hip motor is much more than that on the knee motor, reducing the motor life. In 5-bar link, due to the design, the load is equally distributed on both the motors, thereby increasing the motor life. Also, the 5-bar link design is more stable than the conventional design mechanically. 2.2 Kinematic Analysis Performing Inverse Kinematics using vector addition to find servo angles for a specific position of the leg endpoint. As seen in Figure 1, the coordinates of the leg point that touch the ground are (X, Y). Adding the vectors from origin to (X, Y) through linkage ���⃗⃗���⃗⃗1and ���⃗⃗���⃗⃗2 , we get ⃗���⃗���⃗⃗������ = ���⃗⃗���⃗⃗1 + ���⃗⃗���⃗⃗2 + ������ (1) Here, ���⃗⃗���⃗⃗1 = ‖������������11������������������������������������θθ0011‖ , ���⃗⃗���⃗⃗2 = ‖������������22������������������������������������((θθ0011 + θθ1122))‖ , + ‖���e���������������������������������������((θθ0011 + θθ1122))‖ ������ = + 36

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Figure 1: Schematic diagram of 5-bar linkage ������������ = ������1������������������θ01 + ������2������������ ������(θ01 + θ12) + ������������������������(θ01 + θ12) (2) ������������ = ������1������������������θ01 + ������2������������ ������(θ01 + θ12) + e������������������(θ01 + θ12) (3) (4) Squaring and adding equations (1) and (2), we get (5) ������������������θ12 = ���������2��� + ���������2��� − ������21 −(������2+������)2 2������1(������2+������) Putting this value of θ12 in (1), we get ������������������θ01 = 2������1 ������������ ± √(2������1 ������������)2−4(������21+ ������12)(���������2��� − ������12) 2(������12+ ������12) Here, ������1 = ������1 + (������2 + e) ( ���������2��� + ���������2��� − ������21 −(������2+������)2 ), ������1 = (������2 + e) √1 − ( ���������2��� + ������������2 − ������21 −(������2+������)2 2 2������1(������2+������) 2������1(������2+������) ) As seen in Figure 1, adding the vectors from origin to (X, Y) through linkage ������, ���⃗⃗���⃗⃗4 and ���⃗⃗���⃗⃗3 , we get ⃗���⃗���⃗⃗������ = ������ + ���⃗⃗���⃗⃗4 + ���⃗⃗���⃗⃗3 + ������ (6) Here, ������ = ‖���0���‖ , ���⃗⃗���⃗⃗4 = ‖������������44������������������������������������θθ1100‖ , ‖���e���������������������������������������((θθ0011 ‖������������33������������������������������������((θθ3344 + θθ1100))‖ + θθ1122))‖ ���⃗⃗���⃗⃗3 = + , ������ = + ������������ = ������ + ������4������������������θ10 + ������3������������������(θ34 + θ10) + ������������������������(θ01 + θ12) (7) (8) ������������ = ������4������������������θ10 + ������3������������������(θ34 + θ10) + e������������������(θ01 + θ12) Squaring and adding equations (5) and (6), we get ������������������θ34 = (������������− ������1 )2 + (������������− ������2 )2− ������24 − ������23 (9) 2������4������3 Here, ������1 = ������ + ������������������������(θ01 + θ12), ������2 = e������������������(θ01 + θ12) Putting this value of θ34 in (5), we get ������������������θ10 = 2������2(������������− ������1 ) ± √(2������2(������������− ������1 ))2−4(������22+������22)((������������− ������1 )2−������22) (10) 2(������22+������22) Here, ������2 = ������4 + ������3 ( (������������− ������1 )2 + (������������− ������2 )2− ������24 − ������23 ), ������2 = ������3√1 − ( (������������− ������1 )2 + (������������− ������2 )2− ������24 − ������23 2 2������4������3 2������4������3 ) 37

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 3 SELECTION OF ACTUATORS 3.1 Actuators Mechanical leg movements involve repetitive dynamic events such as impacts, rapid leg swings, and strong interactions with uncertain terrain. Designing actuator systems for highly dynamic legged robots has always been one of the main challenges in robotics research. After defining the nature of the leg structure and the number of joints present, it is most important to select the robot actuator for each joint. Most quadruped robots are driven by a single type of actuator; usually, they are electric, hydraulic, or pneumatic. The assembly of each drive gives its advantages and disadvantages [1]. 3.1.1 Calculation for motor selection Servo motors are a high torque and precise dc motors with feedback. The motion of the servo motor is propor- tional to an electrical signal (known as PWM signal). The Servo motor is working in the feedback control loop. For feedback and monitoring the position of the rotor, servo uses a potentiometer that provides information about the real position of the rotor to a control circuit [7]. Servo motors can be applied in robotics and industrial automation for precise motion with high torque. The calculation is done considering a worst-case scenario when the robot’s weight is supported by just two legs. When using the dimensions for the presented robot configuration, the required motor torque is ������������������������ = 2.5 [Nm]. Each of the four legs includes two electric servo motors, which results in a 2-DOF for each leg. The standard servo motors with 3.5 [Nm] torque for all 8 joints is used for both convenience and modularity. The design of the robot leg is shown in Figure 1. The shaft of the motor can be entirely rotated to 180º in 0.30 seconds. Each servo can provide feedback of speed, shaft angle, voltage and load to the controller. The control algorithm used to maintain the shaft angle can be adjusted individually for each servo, allowing the control of the speed and strength of the motor’s response. 3.2 Control and communication The robot can be controlled using an interactive screen on any mobile device. The communication is executed using Bluetooth 5.0 and an HC-05 Bluetooth receiver. These received Bluetooth signals are then carried to Arduino Mega. The processed signal is further communicated to the servo motor for actuation. Also, feedback is taken from the Inertial Measurement Unit for the proper stability of the mobile robot. All these signals help in the locomotion of the robot. Figure 2 Electronics flowchart 3.2.1 Arduino Mega Arduino Mega is a microcontroller board based on Atmel ATmega2560. 3.2.2 HC-05 Bluetooth Module HC-05 is a Bluetooth module. Bluetooth is used in wireless data communication over short distances for trans- mitting data wirelessly. 3.2.3 IMU An IMU (inertial measurement unit) sensor provides accelerometers and gyroscopes, which allow monitoring of the dynamics of a moving robot body [8] [9]. It manages to simultaneously capture the values of the X, Y, and Z axes. 38

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 4 GAIT ANALYSIS Gait is a synchronized pattern of leg movement [8]. Four-legged animals can perform various leg movements, such as walking, running, galloping, trotting, jogging, jumping, stepping, lateral galloping and so on. The fundamental difference between walking and running gait is that the duty cycle of the walking gait is greater than 0.5, and the duty cycle of the running gait is less than 0.5. In the walking gait, both feet touch the ground at one stage, while in the running gait, both feet are off the ground. Since large animals increase their speed by adjusting their stride length, small animals focus on stride frequency. Robots running at high stride frequency are more stable but less efficient. Trotting mode is the most commonly used gait, practical and direct. In the trotting state, the swing time and support phase of each leg is the same. Figure 3 Gait patterns 5 EXPERIMENTATION The robot was manufactured as proposed in this paper. Every leg was programmed to follow an elliptical path for its forward or backward motion. Trot gait pattern was selected for the robot’s locomotion. The stride length of the respective legs can be changed accordingly in order to make a left or right turn. 5.1 NOMENCLATURE Figure 4 Nomenclature 5.2 MECHANICAL CONSTRUCTION The motors are mechanically interconnected using standard aluminum box-section links (12mm*12mm*0.5mm). These links can be replaced very easily. By using link of different sizes, the dimen- sions of the robot legs and the configuration of the motors can be easily changed. In addition to minimal design and modularity considerations, the selection of these links’ configuration allows for symmetric and sufficiently large workspace. The legs end-links are made up of nylon circular bars coated with a rubber grip. These foot- pads serve as the leg contact points with the ground. 39

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 Figure 5 Manufactured robot 6 RESULTS It was observed that during straight forward or backward motion, the robot did not move in straight path, rather it moved slightly deviated from its straight path. This error of the robot may be caused due to mechanical in- efficiencies of leg like minute length differences in link length from original lengths, varying friction between several pin joints or varying friction over the walking surface. 6.1 OVERCOME SETTINGS As the robot was programmed in such a way that the end point of the leg moves in an ellipse path, its path parameters can be changed using constants like length of semi major axis, semi minor axis, offset distance from origin (h) in x direction or offset distance from origin (k) in y direction. The issues due to mechanical defects can be solved by setting different offsets with Trial-and-Error method. So different offsets were calcu- lated for every leg with Trial-and-Error method to resolve this motion inaccuracy. Values of offsets in the parameters of ellipse are as follows: T__a_b_l_e__2_._R__e_a_d_i_n_g__s____________________________________________________________________________________ Type of motion Output angle(º) Parameter(mm) FL BL FR BR _________________________________________________________________________________ Standing position 20 (right) k 5 5 -5 -5 Forward walking 10(right) h -8 -3 8 4 B__a_c_k__w_a_r_d__r_e_v_e__rs_e_______________1_2__(l_e_f_t_)____________h______________8___________3___________-_6___________-_5__ 7 CONCLUSION The objective of this paper is to provide a compact text that promotes the design and the algorithm of the quadruped robot. The main focus areas associated with this field are locomotion, structural design, gait analy- sis, and actuator. Four-legged robots are suitable for practical applications, such as mine inspection, space exploration, firefighting or where navigation is required in an unconstrained environment. Due to the high- precision joint actuators and controllers, the robustness of the mobile robot is improved. Joint actuators play an important role in considering the complexity, cost and weight of the robot. It is very important to ensure that the joint actuator has a high torque output to weight ratio. The current quadruped robots are limited to visual perceptions. The features like recognition, data learning and memorizing must be implemented to im- prove the autonomy of the robots. The future in the robotics field would require machines that would help people in their personal lives and do some useful work at home. This might create a high demand for quadruped robots with simple yet most efficient features. REFRENCES [1] E. Lucas, \"Huitieme recreation - la machine a marcher,\" Recreat. Math, vol. 4, pp. 198-204, 1894. [2] Y. Geva and A. Shapiro, \"A Novel Design of a Quadruped Robot for Research Purposes,\" International Journal of Advanced Robotic Systems, vol. 11, 2014. 40

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 [3] R. B. Mcghee and A. A. Frank, \"On the stability properties of quadruped creeping gaits,\" Mathematical Biosciences, vol. 3, no. 1-2, pp. 331-351, 1968. [4] I. F, G. G and P. R, \"Exploiting body dynamics for controlling a running quadruped robot,\" in 12th International Conference on Advanced Robotics, 2005. [5] K. F, O. Y and H. S, \"Basic performance experiments for jumping quadruped,\" in IEEE/RSJ International Conference on Intelligent Robots and Systems, 2003. [6] E. Shapiro, M. Ri and S. Shoval, \"A foothold selection algorithm for spider robot locomotion in planar tunnel envi- ronments,\" The International Journal of Robotics Research, vol. 24, no. 10, pp. 823-844, 2005. [7] G. H, M. Z and L. J, \"Design of reduction gear group of 15Kg.cm DC reduction servo motor,\" in International Conference on Electrical and Control Engineering, 2011. [8] N. Ribeiro and C. Santos, \"Inertial measurement units: A brief state of the art on gait analysis,\" in IEEE 5th Portuguese Meeting on Bioengineering, 2017. [9] B. J, L. A, B. S, O. B, M. K, D. K and O. S C, \"An inertial measurement unit (IMU) for an autonomous wireless sensor network,\" in Proceedings of 6th Electronics Packaging Technology Conference (EPTC 2004), 2004. 41

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 SIMULATION OF FATIGUE IN HIGH-TEMPERATURE SUPERCONDUCTOR USING MATAKE CRITERION ROBERT JUSTIN, K.B. ASHOK, JACOB THOMAS RIJO TKM College of Engineering, Department of Mechanical Engineering, Kollam, Kerala, India ABSTRACT: High-temperature superconducting (HTS) tapes are prone to fatigue loadings such as repeated thermal and mechanical load cycles, which will affect the performance of superconductors and lead to the degradation of superconducting magnets. The fatigue tests will continue until either mechanical failure occurs or current is no longer transported. This study focuses on developing Stress based models of fatigue (Matake criterion) using FEA software. The experiment results from the open literature support the predicted fatigue strength of the HTS tape. The fatigue effect is modelled for various stress ratios and applied forces. It is found that with increasing stress ratio, fatigue strength also increases. Furthermore, the fatigue simulation was per- formed at both room and cryogenic temperatures, revealing a fatigue strength difference between room and cryogenic temperatures of approximately 16% of the applied stress. 1 INTRODUCTION Second-generation (2G) high-temperature superconducting (HTS) (RE)Ba2Cu3O7x (REBCO) coated conduc- tor (CC) tapes transmit current effectively and are not particularly susceptible to high magnetic fields. They have a wide range of practical applications due to their promising performance. They are presently employed in devices such as the 45-T superconducting magnet [1]. Figure 1. Modelled geometry of HTS tapes In actual applications where fatigue loading conditions are certain, the strengths or limits of mechanical and electrical fatigue are of vital importance for designing superconducting devices. However, research using the high-cycle uniaxial fatigue test on the 2G CC tapes at or below 77 K is still limited and the determination of the irreversible Ic degradation limit for electric fatigue has not yet been established. High-cycle Uniaxial Fatigue Tests are challenging and time-consuming, yet the electrical and mechanical fatigue limitations must be determined at cryogenic temperatures. However, the electrical and mechanical fatigue strengths and limits should be established in conditions that are representative of real-world applications. For example, regardless of the CC tape process, 4 mm wide CC tapes typically exhibit fatigue cracks initiating at slit edges; therefore, comparative tests with 12 mm wide tapes without slit edges should be conducted to clarify the fatigue frac- ture mechanisms of multilayered REBCO CC tapes under cyclic loading [2] [3]. The fatigue strength at 1 x 106 cycles could be characterised as the mechanical fatigue limit. The limit for 4 mm wide tape is 609 MPa, and the limit for 12 mm wide tape is 679 MPa. The electrical fatigue strength of a CC tape was discovered to be significantly controlled by the fracture behaviour in the SC layer through fractographic measurements, whereas the mechanical fatigue strength was mostly influenced by the substrate [3]. The monotonic tensile stress-strain curve for YBCO coated conductor was measured at room temperature and 77 degrees Celsius. The yield strengths measured by the 0.2 percent offset line were 549 MPa and 667 MPa at RT and 77 K, re- spectively, corresponding to tension loads of 238 N and 267 N [4]. 42

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 2 MODELING Modeling has evolved into an integral component of engineering and design. In numerous sectors of engi- neering, modeling is used for analysis, optimization, virtual production, and so on. Computer simulations have the potential to reduce total production costs as well as product development time. The parametric anal- ysis of variables impacting the performance of a device or system that has to be explored is one of the pow- erful characteristics of analysis software. As illustrated in Figure 1, high-temperature superconducting tapes have a multi-layered structure. The process of making REBCO tape begins with a substrate material (Hastelloy) on which a thin buffer layer and REBCO film are placed, followed by a silver layer and a copper layer. The modeling process can be separat- ed into three steps. At 1020 K, the REBCO layer is initially deposited on the substrate using the metal- organic vapour deposition (MOCVD) technique. Second, at 333 K, copper and silver are electroplated over the tape to ensure electrical stability. Finally, it is cooled to room temperature before being brought up to op- erating temperature (77 K). Because of its small thickness, the buffer layer is ignored. The effect of change in residual compressive strain, which is thermally caused when cooling down from 1020 K to 77 K, is com- puted for various examples of Hastelloy, silver, and copper thickness. A parametric study is also performed to better understand the effect of REBCO tape thickness on thermally generated residual strain at room and liquid nitrogen temperatures. The model under consideration is a piece of tape with dimensions of 4 mm width by 5 mm length and a thickness of 0.093 mm. Some of the assumptions used in the model's development include: linear temperature dependence of ma- terial properties, plastic deformation of copper, silver, and Hastelloy, stress contribution from buffer layer is negligible due to their very small thickness, and REBCO is elastic over the entire range of applied load. 2.1 Mesh and boundary conditions A mesh-independent investigation is carried out to determine the optimum mesh for the fatigue simulation. The optimum mesh is shown in figure 2 and 24 elements are taken along the width, 30 elements along the length, and 6 elements along the thickness of the REBCO tape. The material properties used for the simula- tion are shown in Table 1. The boundary condition is given in such a way that one side of the tape is fixed and tensile load is applied on the other side. The applied load is varied from 248.86N (669 MPa) to 24.886 N (66.9MPa). Figure 2. Meshed geometry of HTS tape 3 THEORY The stress-based Matake criterion is chosen for fatigue simulation. Fatigue evaluations are performed on the plane with the greatest shear stress, which is considered as the critical plane. Then fatigue simulation is car- ried out by calculating maximum normal stress in the critical plane. The Matake criterion based on equation number 1. ������������ (1 + ������������������������������������������) = f (1) 2 43

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 k and f are the normal stress sensitivity coefficient and limit factor.These values are find out by fixing σa= 301.05 MPa,σmax = 669 MPa, σmin = 66.9 MPa, and R (stress ratio) = 0.1 [3]. It may be noted that, limit fac- tor and normal stress sensitivity coefficient are linearly dependent and depicted in figure 3. Figure 3. Normal stress sensitivity coefficient and Limit factor function of Matake criterion The Stress-Based Matake Fatigue Model helps to forecast, whether the tape is safe or damaged. The re- sults of this model are expressed in terms of the fatigue usage factor (FUS), which is defined as the ratio of applied stress to fatigue strength. Fatigue Usage Factor (FUS) = Applied stress (2) Fatigue Strength Table 1: Material properties [5] Material Young’s modulus Yield stress Poisson’s ra- Thermal expansion coef- (GPa) (MPa) tio ficient (K-1) Hastelloy (RT) 223 891 0.307 1.34 x 10-5 Hastelloy (77 K) 228 1141 0.307 1.34 x 10-5 Copper (RT) 80 120 0.34 1.77 x 10-5 Copper (77 K) 98 146 0.34 1.77 x 10-5 Silver 87 225 0.37 3.9 x 10-5 REBCO 157 -- 0.3 1.1 x 10-5 4 VALIDATION OF THE NUMERICAL MODEL The numerical simulation model is successfully validated by comparing this result with the result published in the literature [3] as depicted in figure 4. Both the result showing good agreement and the deviation be- tween the present simulation study and the experimental result is 0.32%. Figure 4:- Validation of simulation with experiment [3]. 44

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 5 RESULTS AND DISCUSSIONS FUS distribution after the fatigue simulation is shown in figure 5. It may be noted that there are different colour spectrums for each layer due to differences in fatigue strength. Fatigue strength of different layers with the variation in the applied stress is shown in figure 6. It may be observed that Hastelloy having a high- er value of FUS, So Hastelloy undergoes the first failure followed by REBCO, copper bottom, silver and copper top. FUS values for the top and bottom copper layers are different, and the bottom copper layer fails first as compared to that of the top copper layer. It may be due to the influence of the adjacent Hastelloy lay- er. Also noted that the fatigue usage factor increases with increasing the applied stress. The FUS value of each layer is influenced by adjacent layers. Figure 5. Distribution of FUS value in HTS tape Figure 6:- FUS variations of different layers with Applied stress 5.1 Fatigue effect on different applied forces Figure 7 depicts the variation of fatigue strength with applied force. The value of fatigue strength is almost constant up to the yield point and the value at the yield point is equal to 610.96 MPa. In usual practice, fa- tigue strength is calculated below the yield point. For better understanding, the force is applied above the yield point. And observed that there is a sudden drop in the fatigue strength after the yield point. 5.2 Fatigue effect on different stress ratios Figure 8 shows that how the fatigue strength varies with changes in the value of stress ratio at cryogenic temperature. Where maximum stress value is taken as constant (669MPa) and the stress ratio changes from - 1 to 0.7. It may be noted that fatigue strength increases with an increase in the stress ratio or when it is shift- ed from compression to tension. The endurance limit of the REBCO tape is found to be 200MPa, corre- sponding to the stress ratio of -1. 45

Proceedings of International e-Conference on Recent Innovations in Mechanical Engineering (RIME) 2021 ©2021, MESA, ME, ITNU ISBN: 978-93-5473-550-9 5.3 Tensile fatigue effect at room and cryogenic temperature The comparison of fatigue strength at cryogenic and room temperature with changes in applied stress is de- picted in figure 9. Where stress ratio is taken as 0.1. It may be noted that fatigue strength varies with temper- ature and an 18% decrease in fatigue strength is observed at room temperature compared to that of a cryo- genic temperature, corresponding to the yield stress (669 MPa). Figure 7:- Nature of fatigue strength with different Applied forces Figure 8:- Variation of fatigue strength with different R values Figure 9:- Comparison between experimental [3] and simulation results Variation of FUS with changes in applied stress for Hastelloy, REBCO and silver at cryogenic and room temperatures are depicted in figure 10. The fatigue strength of the REBCO tape decreases with increasing the temperature. The simulated fatigue usage factor values at 77 K are lower than the FUS values at 293.15 K. REBCO tape undergoes earlier failure at room temperature compared to the fatigue failure at cryogenic tem- perature. The applied stress is increased beyond the yield stress, a sudden increase in FUS at room tempera- ture is observed. However, the FUS increase after the yield point at cryogenic temperature is gradual. Figure 10:- Variation of FUS of different materials with Applied stress at room and cryogenic temperature (Matake). 46