Entropy generation due to the transient mixed convection in a three- dimensional right-angle triangular cavity

Abstract

Entropy generation of the mixed convection in a 3D air -filled right-angle triangular cavity is investigated numerically for the first time by using finite volume method. The vertical right wall of the cavity is considered moving either to the cavity center (+Vp) or downward (−Vp) or towards the cold inclined wall (Vp = 0) with a constant velocity. It is maintained at an isothermal hot temperature (Th). While, the inclined left wall is considered fixed and kept at an isothermal cold temperature (Tc). With respect to the bottom wall, it is considered hot and fixed also. The effects of Richardson number, movement direction of the right vertical wall, entropy generation, Nusselt and Bejan numbers on the flow and thermal fields are illustrated through streamlines, isotherms and entropy generation contours. It is found that the flow field inside the cavity is influenced significantly with the direction of the moving wall. The Bejan number decreases as the Richardson number increases. Moreover, it is observed that highest value of the average Nusselt number can be get when the right hot vertical wall is considered moving to the cavity center (+Vp).