Entropy Generation and Natural Convection in a Square Cavity with a Horizontal Partition and a Heated Square Block

The present work is dedicated to a numerical investigation of natural convection in a differentially heated square enclosure with a solid partition attached to the heated wall and a heating block freely positioned in the cavity. In this study, the length of the solid wall, the position of the heating block, and the Rayleigh numbers of 103, 104, and 105 are investigated for seven different positions of the heating block and three different lengths of the solid partition. The finite difference method through the concept of vorticity-stream function formulation has been applied. The results clearly show that when the heated block is moved towards the cold wall, the average value of the Nusselt number decreases. For high Rayleigh numbers, the average value of the Nusselt number varies proportionally and inversely with the length of the solid partition when the heated block is positioned after or before position 4 respectively. The positive influence of the heated block on the average Nusselt number can be seen when the heated block is moved to the upper heated part of the cavity. The entropy generation is maximum at position 4 for all scenarios.