Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics, 2020
In this paper, a mathematical model to predict acoustic responses of high-speed bearing has been ... more In this paper, a mathematical model to predict acoustic responses of high-speed bearing has been developed and demonstrated in an application of Induction motors. Effect on the acoustic behaviour of bearing has studied by modifying the internal geometry, such as the number of rotating elements, curvature ratio, rotating speed with the oval shape of the track raceway due to pre-operational damage. The mathematical model predicts the contact stress, elliptical contact area, noise level dB and Frequencies of waviness pattern. High-speed bearing is tested at four different speeds to monitor acoustic behaviour. This drive end bearing undergoes different rotational speeds; however, the author has simulated the results at a majorly driven constant speed. The author has incorporated application-level testing at the customized test rig. The mathematical model has simulated using coupled governing equations with the help of the Ranga-Kutta method. The simulation and experimental results prese...
In this paper, the thermal performance of a helically coiled conical cavity receiver is investiga... more In this paper, the thermal performance of a helically coiled conical cavity receiver is investigated under actuation radiation conditions with a 16 m 2 parabolic Scheffler dish concentrator. Under three different radiation scenarios, the receiver thermal energy efficiency, exergy efficiency, and overall heat transfer coefficient are investigated. Water is employed as a heat transfer fluid, and the receiver is tested at a flow rate of 2.5 L per minute in a temperature range of 30-100 • C. During the stagnation test, the receiver's maximum stagnation temperature was recorded as 395 • C for an incoming beam radiation of 654 W/m 2 , which demonstrates the receiver's ability to generate pressurised steam. The overall heat loss coefficient calculated from the stagnation test is 116 W/m 2-K. The heat transfer fluid input and output temperature differences, as well as incoming beam radiation, are found to have a significant impact on the receiver's energy and energy efficiency. Under maximum beam radiation conditions during the second experiment (672 W/m 2), the average thermal energy efficiency and exergy efficiency were determined to be 70.20% and 8.69%, respectively. Based on the findings, this receiver has the potential to be employed in temperature applications up to 100 • C and above for steam generation under pressurised conditions.
International Journal of Manufacturing, Materials, and Mechanical Engineering, 2013
This paper studies mechanical- stress-strain, thermal- temperature distribution, electrical poten... more This paper studies mechanical- stress-strain, thermal- temperature distribution, electrical potential and electric field distribution for 11 kV, single ceramic cap and pin disc insulator assembly used for high voltage transmission and distribution systems. The coupled field finite element computer simulation is carried out by using a commercially available software package, which allows quantifying the effects of insulator assembly on where structural, thermal and electrical load distribution considered simultaneously. The simulation result shows stress concentration due to application of structural, thermal, and electrical load. The stress was maximum on pin and moderate on sealing material and disc. Similarly in electrical analysis, nodal electrical potential and electrical field distribution observed decreasing from bottom pin of insulator assembly to top cup end of insulator model. Remarkable stresses, temperature, electrical potential and electrical field rise was not observed ...
International Journal of Renewable Energy Technology, 2020
In this work, Scheffler dish with improved design of the receiver is used for direct steam genera... more In this work, Scheffler dish with improved design of the receiver is used for direct steam generation. Experiments were conducted from February to May 2019, for monthly performance assessment of 16 m2 Scheffler concentrator. Effect of varying aperture area, solar beam radiation, ambient temperature and wind speed on the thermal efficiency of the system is investigated. The average receiver temperature at focus observed to be 323°C with average beam radiation 656 W/m2. From the results, the thermal efficiency of the system is reduced by 2.36% with a decrease in aperture area from 12.82 m2 to 9.59 m2. The average thermal efficiency of the system decreased linearly from 57.29% to 39.99% with an increase in wind speed from 0.5 m/s to 6 m/s where as it reduced by 1.13% with an increase in ambient temperature from 24°C to 46°C.
Concentrated solar power is a competitive renewable energy technology that offers many advantages... more Concentrated solar power is a competitive renewable energy technology that offers many advantages. Development in the parabolic shape concentrator demands the curved mirrors to harness the maximum solar energy received through the aperture opening. The performance of the concentrated solar collector mainly depends on the characteristic of the reflecting material. High reflective and durable mirrors are required for the viability of a concentrated solar collector. This paper is aimed to present the up to date progress in the solar reflector material and their performance testing. Thick glass mirrors with a protective coating against the weathering have made the place in the solar thermal power plant. However, the use of the glass mirror is limited to only the flat surface reflector. On the other hand, polymer mirrors are flexible but found less durable in outdoor weather conditions and susceptible to elevated temperatures. The reflectivity of stainless steel is lower; it limits the s...
Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) pl... more Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) plays a pivotal role for Indian economy. This study was carried out for assessing ergonomics work environment and risk factors associated with the development of MSDs among the welders employed in 23 MSMEs from Maharashtra. The data was collected from 74 numbers of randomly selected welders. For the assessment of ergonomic work environment along with and standardized Nordic questionnaires for musculoskeletal symptoms; ergonomic questionnaire was used. Data was collected on five point Likert scale and analysis was done using SPSS 21. Results shows that welders have to frequently bend/twist, work above the shoulder, leave the place, manual loading/unloading, lifting load and monotonous and repetitive work for prolonged hours in static posture. There is high rate of musculoskeletal disorders (MSDs) in low back (64.9%), upper back (40.55%), shoulder (36.55%), neck and knees (32.45%) were obser...
This paper addresses the method of multiple cracks detection in moving parts or beams by monitori... more This paper addresses the method of multiple cracks detection in moving parts or beams by monitoring the natural frequency and prediction of crack location and depth using Artificial Neural Networks (ANN). Determination of crack properties like depth and location is vital in the fault diagnosis of rotating machine equipments. For the theoretical analysis, Finite Element Method (FEM) is used wherein the natural frequency of beam is calculated whereas the experimentation is performed using Fast Fourier Transform (FFT) analyzer. In experimentation, simply supported beam with single crack and cantilever beam with two cracks are considered. The experimental results are validated with the results of FEM (ANSYS TM ) software. This formulation can be extended for various boundary conditions as well as varying cross sectional areas. The database obtained by FEM is used for prediction of crack location and depth using Artificial Neural Network (ANN). To investigate the validity of the proposed...
Purpose Aluminium matrix composites are subjected to wear as well as higher temperature applicati... more Purpose Aluminium matrix composites are subjected to wear as well as higher temperature applications such as pistons, cylinder heads and blocks for car engines. Therefore, it is important to evaluate the performance of aluminium metal matrix composite at elevated temperature. Design/methodology/approach In the present work wear performance of Al-TiC composite with 7.5% reinforcement of TiC powder is carried out at elevated temperature. The composite specimens are prepared with the help of centrifugal casting method to get the large segregation of reinforcement on the outer layer of the composite which is subjected to wear. Taguchi method is used for preparing design of experiments. Findings The wear test is performed on DUCOM pin on disc setup having the heating chamber facility. The results of wear test are analysed with the help of MINITAB 19 software. The results show that temperature has dominant effect on the wear rate. The mathematical model through regression is predicted for...
This study presents the experimental analysis of the convex receiver for a Scheffler solar concen... more This study presents the experimental analysis of the convex receiver for a Scheffler solar concentrator. The solar receiver with three different arrangements was tested for steam generation. Thermal performance is determined by energy analysis. An analysis of the receiver with the first arrangement revealed approximately 42% heat losses from the bare receiver. Then a convective heat loss is mitigated by providing a cavity on the receiver. However, no significant improvement in thermal efficiency is observed. Further, the tube coil is fixed on the cavity’s inner wall and water circulated through the coil to harvest the maximum energy. The average intensity of solar beam radiation was 638 W/m2 during the experimentation time of 9:00 to 15:00 h. The stagnation test result estimated that 109 W/m2 K overall heat loss coefficient of the receiver. The receiver’s energy efficiency with the first, second, and third arrangements was obtained to be 57.71%, 60.93%, and 68.03%, respectively, und...
The impact of reradiation and convection losses from the receiver is substantial on the performan... more The impact of reradiation and convection losses from the receiver is substantial on the performance of solar parabolic dish concentrator. In this paper, an experimental and theoretical study to compare the performance of the glazed and unglazed receiver of Scheffler dish for direct steam generation is presented. Tempered glass cover is provided on aperture to reduce the reradiation and convection losses from the receiver. Improvement in the efficiency of the Scheffler dish is found due to suppressed heat losses from the receiver front surface. Overall heat loss coefficient, useful energy transfer rate to water, steam flow rate, and efficiency of the system with and without glass cover on the receiver are evaluated and compared. The average solar beam intensity during experimentation was 569 W/m2 and 600 W/m2 with the glazed and unglazed receiver respectively. The average temperature at the receiver with glazing is recorded as 425oC, even at low solar beam intensity in comparison wit...
Abstract Three-dimensional exact solutions for temperature distribution and thermal stresses in s... more Abstract Three-dimensional exact solutions for temperature distribution and thermal stresses in simply supported finite rectangular orthotropic laminate subjected to prescribed boundary conditions under combined thermal and mechanical loading, are presented which will be used to check the accuracy of more generalized numerical tools. The numerical results are presented for across-ply 3-layered 0/90/0. composite laminate. The numerical results help to draw the conclusion that the influence of the thermal field on deformations and stress is very predominant and induces high transverse normal stress at the interfaces which may cause the failure of the weak interlayer adhesive bond.
Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) pl... more Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) plays a pivotal role for Indian economy. This study was carried out for assessing ergonomics work environment and risk factors associated with the development of MSDs among the welders employed in 23 MSMEs from Maharashtra. The data was collected from 74 numbers of randomly selected welders. For the assessment of ergonomic work environment along with and standardized Nordic questionnaires for musculoskeletal symptoms; ergonomic questionnaire was used. Data was collected on five point Likert scale and analysis was done using SPSS 21. Results shows that welders have to frequently bend/twist, work above the shoulder, leave the place, manual loading/unloading, lifting load and monotonous and repetitive work for prolonged hours in static posture. There is high rate of musculoskeletal disorders (MSDs) in low back (64.9%), upper back (40.55%), shoulder (36.55%), neck and knees (32.45%) were observed. Along with physical factors, demographic factors like age, experience, years of service found positive association with MSDs complaints. Ergonomic intervention programs should be carried out for eliminating risk factors, environmental hazards for safety and well being. Also Simulation studies including posture analyses and biomechanical modeling; are recommended for risk assessments of welders.
Proceedings of International Conference in Mechanical and Energy Technology
In the present scenario, agriculture products are processed (dried) in an open atmosphere. The ra... more In the present scenario, agriculture products are processed (dried) in an open atmosphere. The rate of drying is affected by environmental conditions such as relative humidity, temperature, and solar radiations. Under unfavorable weather conditions, the processing time may go beyond a week, which necessitates a requirement to design equipment to assist the drying process to reduce processing time. In this study, a steam-based heating system called as Steam Based Solar Dryer (SBSD) is designed and fabricated. Atmospheric temperature, relative humidity, and solar radiations are the considered parameters. In order to evaluate the feasibility of equipment, pilot experiments were conducted and the efficiency of SBSD is found to be 29.56%. CFD analysis was performed to investigate the effect of non-uniformity of temperature inside the heating space. It was found that assumption of uniform temperature is not appropriate and non uniform temperature need be incorporated for realistic investigation. It is found that, there is a temperature variation in the SBSD experimentally and CFD analysis.
Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics, 2020
In this paper, a mathematical model to predict acoustic responses of high-speed bearing has been ... more In this paper, a mathematical model to predict acoustic responses of high-speed bearing has been developed and demonstrated in an application of Induction motors. Effect on the acoustic behaviour of bearing has studied by modifying the internal geometry, such as the number of rotating elements, curvature ratio, rotating speed with the oval shape of the track raceway due to pre-operational damage. The mathematical model predicts the contact stress, elliptical contact area, noise level dB and Frequencies of waviness pattern. High-speed bearing is tested at four different speeds to monitor acoustic behaviour. This drive end bearing undergoes different rotational speeds; however, the author has simulated the results at a majorly driven constant speed. The author has incorporated application-level testing at the customized test rig. The mathematical model has simulated using coupled governing equations with the help of the Ranga-Kutta method. The simulation and experimental results prese...
In this paper, the thermal performance of a helically coiled conical cavity receiver is investiga... more In this paper, the thermal performance of a helically coiled conical cavity receiver is investigated under actuation radiation conditions with a 16 m 2 parabolic Scheffler dish concentrator. Under three different radiation scenarios, the receiver thermal energy efficiency, exergy efficiency, and overall heat transfer coefficient are investigated. Water is employed as a heat transfer fluid, and the receiver is tested at a flow rate of 2.5 L per minute in a temperature range of 30-100 • C. During the stagnation test, the receiver's maximum stagnation temperature was recorded as 395 • C for an incoming beam radiation of 654 W/m 2 , which demonstrates the receiver's ability to generate pressurised steam. The overall heat loss coefficient calculated from the stagnation test is 116 W/m 2-K. The heat transfer fluid input and output temperature differences, as well as incoming beam radiation, are found to have a significant impact on the receiver's energy and energy efficiency. Under maximum beam radiation conditions during the second experiment (672 W/m 2), the average thermal energy efficiency and exergy efficiency were determined to be 70.20% and 8.69%, respectively. Based on the findings, this receiver has the potential to be employed in temperature applications up to 100 • C and above for steam generation under pressurised conditions.
International Journal of Manufacturing, Materials, and Mechanical Engineering, 2013
This paper studies mechanical- stress-strain, thermal- temperature distribution, electrical poten... more This paper studies mechanical- stress-strain, thermal- temperature distribution, electrical potential and electric field distribution for 11 kV, single ceramic cap and pin disc insulator assembly used for high voltage transmission and distribution systems. The coupled field finite element computer simulation is carried out by using a commercially available software package, which allows quantifying the effects of insulator assembly on where structural, thermal and electrical load distribution considered simultaneously. The simulation result shows stress concentration due to application of structural, thermal, and electrical load. The stress was maximum on pin and moderate on sealing material and disc. Similarly in electrical analysis, nodal electrical potential and electrical field distribution observed decreasing from bottom pin of insulator assembly to top cup end of insulator model. Remarkable stresses, temperature, electrical potential and electrical field rise was not observed ...
International Journal of Renewable Energy Technology, 2020
In this work, Scheffler dish with improved design of the receiver is used for direct steam genera... more In this work, Scheffler dish with improved design of the receiver is used for direct steam generation. Experiments were conducted from February to May 2019, for monthly performance assessment of 16 m2 Scheffler concentrator. Effect of varying aperture area, solar beam radiation, ambient temperature and wind speed on the thermal efficiency of the system is investigated. The average receiver temperature at focus observed to be 323°C with average beam radiation 656 W/m2. From the results, the thermal efficiency of the system is reduced by 2.36% with a decrease in aperture area from 12.82 m2 to 9.59 m2. The average thermal efficiency of the system decreased linearly from 57.29% to 39.99% with an increase in wind speed from 0.5 m/s to 6 m/s where as it reduced by 1.13% with an increase in ambient temperature from 24°C to 46°C.
Concentrated solar power is a competitive renewable energy technology that offers many advantages... more Concentrated solar power is a competitive renewable energy technology that offers many advantages. Development in the parabolic shape concentrator demands the curved mirrors to harness the maximum solar energy received through the aperture opening. The performance of the concentrated solar collector mainly depends on the characteristic of the reflecting material. High reflective and durable mirrors are required for the viability of a concentrated solar collector. This paper is aimed to present the up to date progress in the solar reflector material and their performance testing. Thick glass mirrors with a protective coating against the weathering have made the place in the solar thermal power plant. However, the use of the glass mirror is limited to only the flat surface reflector. On the other hand, polymer mirrors are flexible but found less durable in outdoor weather conditions and susceptible to elevated temperatures. The reflectivity of stainless steel is lower; it limits the s...
Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) pl... more Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) plays a pivotal role for Indian economy. This study was carried out for assessing ergonomics work environment and risk factors associated with the development of MSDs among the welders employed in 23 MSMEs from Maharashtra. The data was collected from 74 numbers of randomly selected welders. For the assessment of ergonomic work environment along with and standardized Nordic questionnaires for musculoskeletal symptoms; ergonomic questionnaire was used. Data was collected on five point Likert scale and analysis was done using SPSS 21. Results shows that welders have to frequently bend/twist, work above the shoulder, leave the place, manual loading/unloading, lifting load and monotonous and repetitive work for prolonged hours in static posture. There is high rate of musculoskeletal disorders (MSDs) in low back (64.9%), upper back (40.55%), shoulder (36.55%), neck and knees (32.45%) were obser...
This paper addresses the method of multiple cracks detection in moving parts or beams by monitori... more This paper addresses the method of multiple cracks detection in moving parts or beams by monitoring the natural frequency and prediction of crack location and depth using Artificial Neural Networks (ANN). Determination of crack properties like depth and location is vital in the fault diagnosis of rotating machine equipments. For the theoretical analysis, Finite Element Method (FEM) is used wherein the natural frequency of beam is calculated whereas the experimentation is performed using Fast Fourier Transform (FFT) analyzer. In experimentation, simply supported beam with single crack and cantilever beam with two cracks are considered. The experimental results are validated with the results of FEM (ANSYS TM ) software. This formulation can be extended for various boundary conditions as well as varying cross sectional areas. The database obtained by FEM is used for prediction of crack location and depth using Artificial Neural Network (ANN). To investigate the validity of the proposed...
Purpose Aluminium matrix composites are subjected to wear as well as higher temperature applicati... more Purpose Aluminium matrix composites are subjected to wear as well as higher temperature applications such as pistons, cylinder heads and blocks for car engines. Therefore, it is important to evaluate the performance of aluminium metal matrix composite at elevated temperature. Design/methodology/approach In the present work wear performance of Al-TiC composite with 7.5% reinforcement of TiC powder is carried out at elevated temperature. The composite specimens are prepared with the help of centrifugal casting method to get the large segregation of reinforcement on the outer layer of the composite which is subjected to wear. Taguchi method is used for preparing design of experiments. Findings The wear test is performed on DUCOM pin on disc setup having the heating chamber facility. The results of wear test are analysed with the help of MINITAB 19 software. The results show that temperature has dominant effect on the wear rate. The mathematical model through regression is predicted for...
This study presents the experimental analysis of the convex receiver for a Scheffler solar concen... more This study presents the experimental analysis of the convex receiver for a Scheffler solar concentrator. The solar receiver with three different arrangements was tested for steam generation. Thermal performance is determined by energy analysis. An analysis of the receiver with the first arrangement revealed approximately 42% heat losses from the bare receiver. Then a convective heat loss is mitigated by providing a cavity on the receiver. However, no significant improvement in thermal efficiency is observed. Further, the tube coil is fixed on the cavity’s inner wall and water circulated through the coil to harvest the maximum energy. The average intensity of solar beam radiation was 638 W/m2 during the experimentation time of 9:00 to 15:00 h. The stagnation test result estimated that 109 W/m2 K overall heat loss coefficient of the receiver. The receiver’s energy efficiency with the first, second, and third arrangements was obtained to be 57.71%, 60.93%, and 68.03%, respectively, und...
The impact of reradiation and convection losses from the receiver is substantial on the performan... more The impact of reradiation and convection losses from the receiver is substantial on the performance of solar parabolic dish concentrator. In this paper, an experimental and theoretical study to compare the performance of the glazed and unglazed receiver of Scheffler dish for direct steam generation is presented. Tempered glass cover is provided on aperture to reduce the reradiation and convection losses from the receiver. Improvement in the efficiency of the Scheffler dish is found due to suppressed heat losses from the receiver front surface. Overall heat loss coefficient, useful energy transfer rate to water, steam flow rate, and efficiency of the system with and without glass cover on the receiver are evaluated and compared. The average solar beam intensity during experimentation was 569 W/m2 and 600 W/m2 with the glazed and unglazed receiver respectively. The average temperature at the receiver with glazing is recorded as 425oC, even at low solar beam intensity in comparison wit...
Abstract Three-dimensional exact solutions for temperature distribution and thermal stresses in s... more Abstract Three-dimensional exact solutions for temperature distribution and thermal stresses in simply supported finite rectangular orthotropic laminate subjected to prescribed boundary conditions under combined thermal and mechanical loading, are presented which will be used to check the accuracy of more generalized numerical tools. The numerical results are presented for across-ply 3-layered 0/90/0. composite laminate. The numerical results help to draw the conclusion that the influence of the thermal field on deformations and stress is very predominant and induces high transverse normal stress at the interfaces which may cause the failure of the weak interlayer adhesive bond.
Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) pl... more Uday V. Aswalekar Vinod B. Tungikar Abstract Micro, Small and Medium Sized Enterprises (MSMEs) plays a pivotal role for Indian economy. This study was carried out for assessing ergonomics work environment and risk factors associated with the development of MSDs among the welders employed in 23 MSMEs from Maharashtra. The data was collected from 74 numbers of randomly selected welders. For the assessment of ergonomic work environment along with and standardized Nordic questionnaires for musculoskeletal symptoms; ergonomic questionnaire was used. Data was collected on five point Likert scale and analysis was done using SPSS 21. Results shows that welders have to frequently bend/twist, work above the shoulder, leave the place, manual loading/unloading, lifting load and monotonous and repetitive work for prolonged hours in static posture. There is high rate of musculoskeletal disorders (MSDs) in low back (64.9%), upper back (40.55%), shoulder (36.55%), neck and knees (32.45%) were observed. Along with physical factors, demographic factors like age, experience, years of service found positive association with MSDs complaints. Ergonomic intervention programs should be carried out for eliminating risk factors, environmental hazards for safety and well being. Also Simulation studies including posture analyses and biomechanical modeling; are recommended for risk assessments of welders.
Proceedings of International Conference in Mechanical and Energy Technology
In the present scenario, agriculture products are processed (dried) in an open atmosphere. The ra... more In the present scenario, agriculture products are processed (dried) in an open atmosphere. The rate of drying is affected by environmental conditions such as relative humidity, temperature, and solar radiations. Under unfavorable weather conditions, the processing time may go beyond a week, which necessitates a requirement to design equipment to assist the drying process to reduce processing time. In this study, a steam-based heating system called as Steam Based Solar Dryer (SBSD) is designed and fabricated. Atmospheric temperature, relative humidity, and solar radiations are the considered parameters. In order to evaluate the feasibility of equipment, pilot experiments were conducted and the efficiency of SBSD is found to be 29.56%. CFD analysis was performed to investigate the effect of non-uniformity of temperature inside the heating space. It was found that assumption of uniform temperature is not appropriate and non uniform temperature need be incorporated for realistic investigation. It is found that, there is a temperature variation in the SBSD experimentally and CFD analysis.
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Papers by Vinod Tungikar