SUNNY CHANDRA - Academia.edu (original) (raw)
Papers by SUNNY CHANDRA
Solid State Technology, Dec 11, 2020
— In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat si... more — In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat sink of diameter (350 micron) has been analysed for three different inlet temperatures of deionized water (19oC, 23.5oC, and 28.6oC) at an ambient saturation temperature of 29oC by varying mass flow rate from 0.006 kg/s to 0.028 kg/s and exit vapour quality from 0.1 to 0.9 at a fixed heat input of 72 W. It has been observed that exergy efficiency decreases with increase of mass flow rate with a maximum decrement of 17.05% for inlet temperature of 28.6oC because of the rise in average surface temperature at higher flow rate of the test section when pressure drop is fixed. Exergy efficiency has been found to be increase with pressure drop, pumping power and exit vapour quality while at higher pressure drop, pumping power and vapour quality exergy efficiency becomes uniform when mass flow rate is fixed. Keywords- Exergy efficiency, Semicircular microchannel,heat sink, Surface temperature, Mass flow rate, Fixed heat input
Solid State Technology, Mar 25, 2020
In this paper, a feasible optimization scheme for rectangular microchannel heat sinks, which inco... more In this paper, a feasible optimization scheme for rectangular microchannel heat sinks, which incorporates the thermal resistance model and the Improved Strength Pareto Evolutionary Algorithm (SPEA2), is reported. An alternative coolant, namely, ammonia gas, is used to improve the overall thermal and hydrodynamic performances of the considered system. Results from the optimization showed significant reduction in the total thermal resistance compared to the conventional air-cooled systems up to 35% for the same allowable pumping power. The SPEA2 exhibited excellent performance when it was compared to another multiobjective algorithm, NSGA2. The results reported in this study open the door for the incorporation of some other algorithms, which have not been used in the optimization of microchannel heat sinks. Finally, the outcome of this paper predicts a promising future for the usage of ammonia gas in the area of electronics cooling.
International journal of innovative technology and exploring engineering, Sep 30, 2019
Demand for greater capability of electronic devices in very small volume for compactness has affe... more Demand for greater capability of electronic devices in very small volume for compactness has affected huge augmentations in heat indulgence at all stages of device, electronic wrapping, test section and system. Latest cooling systems are hence needed to eliminate the released heat while maintaining compactness of the device. The micro-channel heat sink (MCHS) is ideal for this situation as it consists of channels of micron size which offers an extended surface area to volume ratio of approximately 15.294 m 2 / m 3 compared to 650 m 2 / m 3 for a typical heat compact exchanger. A comprehensive review has been done for consequence of heat flux (q o), mass flux (G), vapour quality (x) and channel geometries at flow patterns and heat dissipation of MCHS. The study show that to increase the rate of heat transfer by using different channel geometries like converging-diverging, segmented etc. compared to conventional rectangular micro-channels has given better cooling effect The Flow patterns like bubbly, slug flow are associated with nucleate boiling dominated in low vapour quality and annular flow also given the significant effect on heat transfer in higher vapour quality region.
IntechOpen eBooks, Dec 21, 2022
Phase Change Materials - Technology and Applications [Working Title]
In today’s era demand of fast processing speed and superior performance of electronic devices cre... more In today’s era demand of fast processing speed and superior performance of electronic devices creates the problem of huge amount of heat generation. About 100 W/cm2 heat fluxes has been generating from advanced microprocessors of latest electronic devices and heat dissipation limited to 37 W/cm2 for air cooling. Semi-circular micro-channel heat sink with Phase change materials still needs to be investigated for the cooling of latest electronic devices as combination of large heat transfer area within a small volume of heat sink and large latent heat released from PCM provides huge amount of heat transfer coefficient which is required to be achieved in the present work. Analytical study of micro-channel heat sink has been performed in the present work at a constant power supply of 95 W using PCM slurry at φ = 0.25 and φ = 0.50 for flow rate in the range of 75 ml/min to 300 ml/min. Heat transfer coefficient of slurry and Nu increases with increase in flow rate. At φ = 0.25 higher heat...
International Journal of Innovative Technology and Exploring Engineering, 2019
Demand for greater capability of electronic devices in very small volume for compactness has affe... more Demand for greater capability of electronic devices in very small volume for compactness has affected huge augmentations in heat indulgence at all stages of device, electronic wrapping, test section and system. Latest cooling systems are hence needed to eliminate the released heat while maintaining compactness of the device. The micro-channel heat sink (MCHS) is ideal for this situation as it consists of channels of micron size which offers an extended surface area to volume ratio of approximately 15.294 m2 / m3 compared to 650 m2 / m3 for a typical heat compact exchanger. A comprehensive review has been done for consequence of heat flux (qo), mass flux (G), vapour quality (x) and channel geometries at flow patterns and heat dissipation of MCHS. The study show that to increase the rate of heat transfer by using different channel geometries like converging-diverging, segmented etc. compared to conventional rectangular micro-channels has given better cooling effect The Flow patterns l...
— In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat si... more — In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat sink of diameter (350 micron) has been analysed for three different inlet temperatures of deionized water (19oC, 23.5oC, and 28.6oC) at an ambient saturation temperature of 29oC by varying mass flow rate from 0.006 kg/s to 0.028 kg/s and exit vapour quality from 0.1 to 0.9 at a fixed heat input of 72 W. It has been observed that exergy efficiency decreases with increase of mass flow rate with a maximum decrement of 17.05% for inlet temperature of 28.6oC because of the rise in average surface temperature at higher flow rate of the test section when pressure drop is fixed. Exergy efficiency has been found to be increase with pressure drop, pumping power and exit vapour quality while at higher pressure drop, pumping power and vapour quality exergy efficiency becomes uniform when mass flow rate is fixed. Keywords- Exergy efficiency, Semicircular microchannel,heat sink, Surface temperature, Mass flow rate, Fixed heat input
Solid State Technology, Dec 11, 2020
— In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat si... more — In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat sink of diameter (350 micron) has been analysed for three different inlet temperatures of deionized water (19oC, 23.5oC, and 28.6oC) at an ambient saturation temperature of 29oC by varying mass flow rate from 0.006 kg/s to 0.028 kg/s and exit vapour quality from 0.1 to 0.9 at a fixed heat input of 72 W. It has been observed that exergy efficiency decreases with increase of mass flow rate with a maximum decrement of 17.05% for inlet temperature of 28.6oC because of the rise in average surface temperature at higher flow rate of the test section when pressure drop is fixed. Exergy efficiency has been found to be increase with pressure drop, pumping power and exit vapour quality while at higher pressure drop, pumping power and vapour quality exergy efficiency becomes uniform when mass flow rate is fixed. Keywords- Exergy efficiency, Semicircular microchannel,heat sink, Surface temperature, Mass flow rate, Fixed heat input
Solid State Technology, Mar 25, 2020
In this paper, a feasible optimization scheme for rectangular microchannel heat sinks, which inco... more In this paper, a feasible optimization scheme for rectangular microchannel heat sinks, which incorporates the thermal resistance model and the Improved Strength Pareto Evolutionary Algorithm (SPEA2), is reported. An alternative coolant, namely, ammonia gas, is used to improve the overall thermal and hydrodynamic performances of the considered system. Results from the optimization showed significant reduction in the total thermal resistance compared to the conventional air-cooled systems up to 35% for the same allowable pumping power. The SPEA2 exhibited excellent performance when it was compared to another multiobjective algorithm, NSGA2. The results reported in this study open the door for the incorporation of some other algorithms, which have not been used in the optimization of microchannel heat sinks. Finally, the outcome of this paper predicts a promising future for the usage of ammonia gas in the area of electronics cooling.
International journal of innovative technology and exploring engineering, Sep 30, 2019
Demand for greater capability of electronic devices in very small volume for compactness has affe... more Demand for greater capability of electronic devices in very small volume for compactness has affected huge augmentations in heat indulgence at all stages of device, electronic wrapping, test section and system. Latest cooling systems are hence needed to eliminate the released heat while maintaining compactness of the device. The micro-channel heat sink (MCHS) is ideal for this situation as it consists of channels of micron size which offers an extended surface area to volume ratio of approximately 15.294 m 2 / m 3 compared to 650 m 2 / m 3 for a typical heat compact exchanger. A comprehensive review has been done for consequence of heat flux (q o), mass flux (G), vapour quality (x) and channel geometries at flow patterns and heat dissipation of MCHS. The study show that to increase the rate of heat transfer by using different channel geometries like converging-diverging, segmented etc. compared to conventional rectangular micro-channels has given better cooling effect The Flow patterns like bubbly, slug flow are associated with nucleate boiling dominated in low vapour quality and annular flow also given the significant effect on heat transfer in higher vapour quality region.
IntechOpen eBooks, Dec 21, 2022
Phase Change Materials - Technology and Applications [Working Title]
In today’s era demand of fast processing speed and superior performance of electronic devices cre... more In today’s era demand of fast processing speed and superior performance of electronic devices creates the problem of huge amount of heat generation. About 100 W/cm2 heat fluxes has been generating from advanced microprocessors of latest electronic devices and heat dissipation limited to 37 W/cm2 for air cooling. Semi-circular micro-channel heat sink with Phase change materials still needs to be investigated for the cooling of latest electronic devices as combination of large heat transfer area within a small volume of heat sink and large latent heat released from PCM provides huge amount of heat transfer coefficient which is required to be achieved in the present work. Analytical study of micro-channel heat sink has been performed in the present work at a constant power supply of 95 W using PCM slurry at φ = 0.25 and φ = 0.50 for flow rate in the range of 75 ml/min to 300 ml/min. Heat transfer coefficient of slurry and Nu increases with increase in flow rate. At φ = 0.25 higher heat...
International Journal of Innovative Technology and Exploring Engineering, 2019
Demand for greater capability of electronic devices in very small volume for compactness has affe... more Demand for greater capability of electronic devices in very small volume for compactness has affected huge augmentations in heat indulgence at all stages of device, electronic wrapping, test section and system. Latest cooling systems are hence needed to eliminate the released heat while maintaining compactness of the device. The micro-channel heat sink (MCHS) is ideal for this situation as it consists of channels of micron size which offers an extended surface area to volume ratio of approximately 15.294 m2 / m3 compared to 650 m2 / m3 for a typical heat compact exchanger. A comprehensive review has been done for consequence of heat flux (qo), mass flux (G), vapour quality (x) and channel geometries at flow patterns and heat dissipation of MCHS. The study show that to increase the rate of heat transfer by using different channel geometries like converging-diverging, segmented etc. compared to conventional rectangular micro-channels has given better cooling effect The Flow patterns l...
— In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat si... more — In this paper exergy efficiency or second law efficiency of a semicircular microchannel heat sink of diameter (350 micron) has been analysed for three different inlet temperatures of deionized water (19oC, 23.5oC, and 28.6oC) at an ambient saturation temperature of 29oC by varying mass flow rate from 0.006 kg/s to 0.028 kg/s and exit vapour quality from 0.1 to 0.9 at a fixed heat input of 72 W. It has been observed that exergy efficiency decreases with increase of mass flow rate with a maximum decrement of 17.05% for inlet temperature of 28.6oC because of the rise in average surface temperature at higher flow rate of the test section when pressure drop is fixed. Exergy efficiency has been found to be increase with pressure drop, pumping power and exit vapour quality while at higher pressure drop, pumping power and vapour quality exergy efficiency becomes uniform when mass flow rate is fixed. Keywords- Exergy efficiency, Semicircular microchannel,heat sink, Surface temperature, Mass flow rate, Fixed heat input