EXAMINATION OF CONVECTIVE HEAT TRANSFER AND ENTROPY GENERATION BY TWO ADIABATIC OBSTACLES INSIDE A CAVITY AT DIFFERENT INCLINATION ANGLES

Abstract

This paper investigates numerically the problem of convective heat transfer and entropy generation by two adiabatic obstacles positioned inside a square cavity heated at the left wall and cooled on the right wall while horizontal walls are adiabatic. The inclination angle of the cavity orientation investigated are 30, 60 and 90 degrees. Rayleigh numbers ranging from 10 3 to 10 6 were calculated for two vertical obstacles. The method of Galerkin finite element was employed to solve the conservation equations of mass, momentum and energy. The cavity is assumed to be filled with air with Prandtl number of 0.71. It was observed that at 30 degree inclination, temperature distribution at the top of the cavity is more pronounced compared to the temperature at the lower region where adiabatic obstacles are positioned. Consequently, increase in Rayleigh number improve this behavior in all inclination angles considered. These results show that the effects of inclination angles and adiabatic obstacles on the thermal behaviours and fluid flow characteristics within the cavity are significantly evident. Rayleigh and Nusselt numbers strongly affect heat transfer rates proportionately. Also, high temperature gradients exist at regions where entropy is generated.