2531 Words11 Pages

Heat transfer by mixed convection of air inside a rectangular enclosure is investigated numerically. Different placement configurations of inlet opening are considered. A constant flux heat source was heated vertical wall. The fluid considered is air. The other side walls including the top and bottom of the enclosure were assumed to be adiabatic. The inlet opening, located on the left vertical wall, was placed at varying locations. The outlet opening was placed on the opposite heated wall at a fixed location. The basis of the investigation was the two–dimensional numerical solutions of governing equations by using Finite Difference Method (FDM).Significant parameters considered were Richardson number (Ri) and Reynolds number (Re). Results are*…show more content…*

It may include bulk mass transfer from convection process. Laminar flow: This is the flow of the fluid in which adjoining layers of fluid flow parallel to one another. All the fluids particles move in distinct and separate layer without mixing within layers. Turbulent flow: This is the flow of fluid in which its velocity at any point varies rapidly in an irregular manner. Viscosity: This is an internal property of fluid that offers resistance to flow. Thermal conductivity: This is the quantity of heat transmitted through unit thickness in direction normal to a surface. Specific heat: This is amount of heat per unit mass required to raise the temperature by one kelvin 1.3 Literature Review Various researchers have carried out investigations into the effect of mixed convective flows in rectangular enclosures by using analytical, experimental, and numerical*…show more content…*

They found that the overall normalized Nusselt number as well as irreversibility was strongly affected by both the location of the exit port and the aspect ratio. Singh and Sharif (2003) studied mixed convection in an air-cooled rectangular cavity with differentially heated vertical isothermal side walls having inlet and exit port. Several different placement configurations of the inlet and exit ports were investigated. The best configuration was selected by analyzing the cooling effectiveness of the cavity which suggested that injecting air through the bottom of cold wall and exiting near the top of the hot wall was more effective in heat removal. The forced and natural convection assist each other in the heat removal

It may include bulk mass transfer from convection process. Laminar flow: This is the flow of the fluid in which adjoining layers of fluid flow parallel to one another. All the fluids particles move in distinct and separate layer without mixing within layers. Turbulent flow: This is the flow of fluid in which its velocity at any point varies rapidly in an irregular manner. Viscosity: This is an internal property of fluid that offers resistance to flow. Thermal conductivity: This is the quantity of heat transmitted through unit thickness in direction normal to a surface. Specific heat: This is amount of heat per unit mass required to raise the temperature by one kelvin 1.3 Literature Review Various researchers have carried out investigations into the effect of mixed convective flows in rectangular enclosures by using analytical, experimental, and numerical

They found that the overall normalized Nusselt number as well as irreversibility was strongly affected by both the location of the exit port and the aspect ratio. Singh and Sharif (2003) studied mixed convection in an air-cooled rectangular cavity with differentially heated vertical isothermal side walls having inlet and exit port. Several different placement configurations of the inlet and exit ports were investigated. The best configuration was selected by analyzing the cooling effectiveness of the cavity which suggested that injecting air through the bottom of cold wall and exiting near the top of the hot wall was more effective in heat removal. The forced and natural convection assist each other in the heat removal

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