Dr. B Sadashive Gowda - Academia.edu (original) (raw)
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Papers by Dr. B Sadashive Gowda
European Journal of Molecular & Clinical Medicine, Apr 11, 2021
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations for the conduction heat transfer in the foods, simultaneous heat and mass transfer at the food-aiir interface and in the air stream are solved numerically using finite-difference methods. A comprehensive numerical study is performed by varying the process parameters over a wide range. Typical results showing the variation of moist air properties along the height of the package and the effect of each parameter on the process time are presented. The ranges of parameters for advantageous operation of the precooling system are identified. Correlations are obtained for the process time based on the product center and mass-averaged temperatures in terms of process parameters.
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations
This paper deals with the numerical analysis of 3d model of a cold store of dimensions 4.5 m (L) ... more This paper deals with the numerical analysis of 3d model of a cold store of dimensions 4.5 m (L) x 3.3 m (W) x 2.5 m (H), which is developed to study the effects of design parameters on flow and temperature fields within the cold store. The variation in number of inlets, position of inlets and stacking methodology affect flow and temperature fields within the cold store. Results of CFD simulation indicated the optimum position of the inlets, number of inlets and stacking methodology required to have uniform flow and temperature field within the cold store. It also proved that CFD is a convenient tool for designing and optimizing the flow field in the cold store.
Materials Today: Proceedings, 2020
Data centres (DCs) are often provided with adequate air conditioning units to meet cooling needs.... more Data centres (DCs) are often provided with adequate air conditioning units to meet cooling needs. Failure free operation is the primary goal of any DC, as equipment failure in a DC is very expensive. If inefficiencies involved in heat removal process can be reduced, there will be a significant reduction in energy consumption. This paper provides a review of existing air cooling and liquid cooling techniques to remove the heat from the DCs effectively. It includes the potential viability of free cooling & reusing heat for other applications.
This paper deals with numerical analysis of 3D model of an SSHE is developed in order to study th... more This paper deals with numerical analysis of 3D model of an SSHE is developed in order to study the fluid flow and heat transfer with a steady state laminar, non-isothermal flow of pure glycerine, which can be treated as a Newtonian fluid. The variation of the local heat transfer coefficient based on the inner wall temperature and bulk fluid temperature as a function of the main process parameters, namely, rotational Reynolds number (Re rot ), axial Reynolds number (Re axi ) and number of scraper blades (2, 3 and 4), is obtained. The results have shown that viscous dissipation has a significant effect on the cooling of glycerine. The local heat transfer coefficient increases slightly when increasing the number of scraper blades. Larger increases of the same occurred with higher rotational Reynolds number and axial Reynolds number. A correlation of the average Nusselt number is obtained in terms of the rotational and axial Reynolds numbers. This is expected to be useful in the design ...
This paper deals with the numerical analysis of a Hybrid-Type (PV/T) Solar Air Heater and a study... more This paper deals with the numerical analysis of a Hybrid-Type (PV/T) Solar Air Heater and a study on the effect of various design parameters that enhance the performance of the system. The heat transfer improvement in general may be achieved by increasing the heat transfer coefficient or by increasing the surface area or by increasing both. The main objective of the present work is to determine the optimum air mass flow rate at which PV/T systems are to be operated and to develop an optimal design of a hybrid type (PV/T) solar air heater that shows better performance at various heat fluxes due to solar radiation. This study determines the set of design parameters which lead to the best annual yield of the system. In this study of a hybrid type (PV/T) solar air heater ICEM CFD (ANSYS) is used to obtain the optimum results, thereby increasing the efficiency of the system.
Numerical investigations have been carried out for an annular type gas turbine exhaust diffuser w... more Numerical investigations have been carried out for an annular type gas turbine exhaust diffuser with inlet guidevanes and with and without struts. Numerical simulations were carried out to determine the pressure recovery coefficient, for a divergence angle 13 o by keeping the diffusion length constant. The flow conditions at the inlet are varied to evaluate how they affect the flow development in the passage. The velocity at inlet is varied from 80 m/s to 160 m/s in the steps of 40 m/s. In the present study a (1/6)th part of the model is considered for the analysis, due to symmetry. The results for with and without struts indicates how the pressure recovery coefficient affects the efficiency of the turbine.
This paper deals with Computational Fluid Dynamic (CFD) analysis of 3D model of an SSHE is develo... more This paper deals with Computational Fluid Dynamic (CFD) analysis of 3D model of an SSHE is developed in order to study the fluid flow and heat transfer with a steady state laminar, non-isothermal flow of pure glycerine, which can be treated as a newtonian fluid. The variation of the local heat transfer coefficient based on the inner wall temperature and bulk fluid temperature as a function of the main process parameters, namely, rotational Reynolds number (Rerot), axial Reynolds number (Reaxi) and dimensionless clearance, is obtained. The results have shown that viscous dissipation has a significant effect on the cooling of glycerine. The local heat transfer coefficient increases slightly when the tip clearance increases. Larger increases of the same occurred with higher rotational Reynolds number and axial Reynolds number. A correlation of the average Nusselt number is obtained in terms of the rotational and axial Reynolds numbers. This is expected to be useful in the design of SSH...
Procedia Computer Science
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations
International Journal of Air-Conditioning and Refrigeration
Numerical simulation of a mini-channel, flat-tube, louvered fin, automotive condenser is performe... more Numerical simulation of a mini-channel, flat-tube, louvered fin, automotive condenser is performed to study the heat rejection rate, pressure drop and performance of the heat exchanger. The simulation study is carried out for the refrigerant R1234yf. The properties of R1234y are obtained from REFPROP software. The moist air properties are calculated from those of dry air and water vapor using suitable correlations. To select the input data, the cycle performance is carried out for a standard vapor compression refrigeration system working with R1234yf between the temperature limits of [Formula: see text]C on the low-pressure side and [Formula: see text]C on the high-pressure side. The condensation process is taken into account in three sections, namely, the superheated, two-phase and the subcooled regions. A custom code is prepared in MATLAB to solve the simultaneous equations of heat transfer from refrigerant to inside tube wall, inside tube wall to outside tube wall and outside tub...
Procedia Computer Science
Procedia Computer Science
European Journal of Molecular & Clinical Medicine, Apr 11, 2021
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations for the conduction heat transfer in the foods, simultaneous heat and mass transfer at the food-aiir interface and in the air stream are solved numerically using finite-difference methods. A comprehensive numerical study is performed by varying the process parameters over a wide range. Typical results showing the variation of moist air properties along the height of the package and the effect of each parameter on the process time are presented. The ranges of parameters for advantageous operation of the precooling system are identified. Correlations are obtained for the process time based on the product center and mass-averaged temperatures in terms of process parameters.
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations
This paper deals with the numerical analysis of 3d model of a cold store of dimensions 4.5 m (L) ... more This paper deals with the numerical analysis of 3d model of a cold store of dimensions 4.5 m (L) x 3.3 m (W) x 2.5 m (H), which is developed to study the effects of design parameters on flow and temperature fields within the cold store. The variation in number of inlets, position of inlets and stacking methodology affect flow and temperature fields within the cold store. Results of CFD simulation indicated the optimum position of the inlets, number of inlets and stacking methodology required to have uniform flow and temperature field within the cold store. It also proved that CFD is a convenient tool for designing and optimizing the flow field in the cold store.
Materials Today: Proceedings, 2020
Data centres (DCs) are often provided with adequate air conditioning units to meet cooling needs.... more Data centres (DCs) are often provided with adequate air conditioning units to meet cooling needs. Failure free operation is the primary goal of any DC, as equipment failure in a DC is very expensive. If inefficiencies involved in heat removal process can be reduced, there will be a significant reduction in energy consumption. This paper provides a review of existing air cooling and liquid cooling techniques to remove the heat from the DCs effectively. It includes the potential viability of free cooling & reusing heat for other applications.
This paper deals with numerical analysis of 3D model of an SSHE is developed in order to study th... more This paper deals with numerical analysis of 3D model of an SSHE is developed in order to study the fluid flow and heat transfer with a steady state laminar, non-isothermal flow of pure glycerine, which can be treated as a Newtonian fluid. The variation of the local heat transfer coefficient based on the inner wall temperature and bulk fluid temperature as a function of the main process parameters, namely, rotational Reynolds number (Re rot ), axial Reynolds number (Re axi ) and number of scraper blades (2, 3 and 4), is obtained. The results have shown that viscous dissipation has a significant effect on the cooling of glycerine. The local heat transfer coefficient increases slightly when increasing the number of scraper blades. Larger increases of the same occurred with higher rotational Reynolds number and axial Reynolds number. A correlation of the average Nusselt number is obtained in terms of the rotational and axial Reynolds numbers. This is expected to be useful in the design ...
This paper deals with the numerical analysis of a Hybrid-Type (PV/T) Solar Air Heater and a study... more This paper deals with the numerical analysis of a Hybrid-Type (PV/T) Solar Air Heater and a study on the effect of various design parameters that enhance the performance of the system. The heat transfer improvement in general may be achieved by increasing the heat transfer coefficient or by increasing the surface area or by increasing both. The main objective of the present work is to determine the optimum air mass flow rate at which PV/T systems are to be operated and to develop an optimal design of a hybrid type (PV/T) solar air heater that shows better performance at various heat fluxes due to solar radiation. This study determines the set of design parameters which lead to the best annual yield of the system. In this study of a hybrid type (PV/T) solar air heater ICEM CFD (ANSYS) is used to obtain the optimum results, thereby increasing the efficiency of the system.
Numerical investigations have been carried out for an annular type gas turbine exhaust diffuser w... more Numerical investigations have been carried out for an annular type gas turbine exhaust diffuser with inlet guidevanes and with and without struts. Numerical simulations were carried out to determine the pressure recovery coefficient, for a divergence angle 13 o by keeping the diffusion length constant. The flow conditions at the inlet are varied to evaluate how they affect the flow development in the passage. The velocity at inlet is varied from 80 m/s to 160 m/s in the steps of 40 m/s. In the present study a (1/6)th part of the model is considered for the analysis, due to symmetry. The results for with and without struts indicates how the pressure recovery coefficient affects the efficiency of the turbine.
This paper deals with Computational Fluid Dynamic (CFD) analysis of 3D model of an SSHE is develo... more This paper deals with Computational Fluid Dynamic (CFD) analysis of 3D model of an SSHE is developed in order to study the fluid flow and heat transfer with a steady state laminar, non-isothermal flow of pure glycerine, which can be treated as a newtonian fluid. The variation of the local heat transfer coefficient based on the inner wall temperature and bulk fluid temperature as a function of the main process parameters, namely, rotational Reynolds number (Rerot), axial Reynolds number (Reaxi) and dimensionless clearance, is obtained. The results have shown that viscous dissipation has a significant effect on the cooling of glycerine. The local heat transfer coefficient increases slightly when the tip clearance increases. Larger increases of the same occurred with higher rotational Reynolds number and axial Reynolds number. A correlation of the average Nusselt number is obtained in terms of the rotational and axial Reynolds numbers. This is expected to be useful in the design of SSH...
Procedia Computer Science
International Journal of Heat and Fluid Flow, 1997
In this paper, a mathematical model for forced-air precooling of spherical food products in bulk ... more In this paper, a mathematical model for forced-air precooling of spherical food products in bulk is developed. The foods are arranged in horizontal layers stacked one above the other to form a rectangular parallelepiped with a vertical gap in between the product layers. The foods are cooled by chilled air blown along the height of the package. The governing equations
International Journal of Air-Conditioning and Refrigeration
Numerical simulation of a mini-channel, flat-tube, louvered fin, automotive condenser is performe... more Numerical simulation of a mini-channel, flat-tube, louvered fin, automotive condenser is performed to study the heat rejection rate, pressure drop and performance of the heat exchanger. The simulation study is carried out for the refrigerant R1234yf. The properties of R1234y are obtained from REFPROP software. The moist air properties are calculated from those of dry air and water vapor using suitable correlations. To select the input data, the cycle performance is carried out for a standard vapor compression refrigeration system working with R1234yf between the temperature limits of [Formula: see text]C on the low-pressure side and [Formula: see text]C on the high-pressure side. The condensation process is taken into account in three sections, namely, the superheated, two-phase and the subcooled regions. A custom code is prepared in MATLAB to solve the simultaneous equations of heat transfer from refrigerant to inside tube wall, inside tube wall to outside tube wall and outside tub...
Procedia Computer Science
Procedia Computer Science