Department of Mechanical Engineering, National Institute of Technology Agartala, Tripura, 799055
The effect of different configurations of partial cold walls on laminar natural convection heat transfer for a right-angle triangular cavity heated from below has been studied numerically. The enclosure is filled with water and heat transfer surfaces such as hot and cold walls are maintained at constant temperature. The side and hypotenuse walls of the enclosure are detached from the middle and have been arranged in four different configurations, namely AB, BC, AD and CD for cooling purpose. The finite volume method is used to solve the dimensionless governing mass, momentum and energy equations. The problem has been solved to explore the effects of the pertinent parameters i.e. different configurations of cold walls and variation of Rayleigh number (105 ≤ Ra ≤ 107). Results are obtained from numerical simulation using commercial software package, FLUENT and presented in the form of streamlines and isotherms. The thermal performance of the enclosure has been expressed by local and average Nusselt numbers. From the analysis, it is observed that the temperature distribution and flow field are significantly affected by these parameters. The high heat transfer rate has been observed for the position AB while low for the position CD. Also, the heat transfer rate enhances as the Rayleigh number (Ra) increases.