Effect of heating condition on entropy generation of conjugate natural convection in a prismatic enclosure

Abstract

Conjugate natural convection heat transfer inside a prismatic enclosure with thick solid bottom wall has been investigated in the present study. The enclosure is filled with air and the solid bottom wall, made of pine wood, has finite thickness of t = 0.10L, where L is the length of the bottom wall of the enclosure. Three different cases such as isothermal, linear and sinusoidally varying heating conditions are applied at the bottom of the enclosure to examine the thermal performance and entropy generation inside the enclosure. The governing Navier-Stokes and energy equations are solved using finite element method. Parametric simulation is carried out for a range of Rayleigh number, 103 ≤ Ra ≤ 107 and the visualization of flow and thermal fields is presented through streamline, isotherm and entropy contour plots. The variations of average fluid temperature inside the enclosure, the average Nusselt number along the top of the thick bottom wall and the total entropy generation are also examined in order to assess the influence of the above three heating conditions.Conjugate natural convection heat transfer inside a prismatic enclosure with thick solid bottom wall has been investigated in the present study. The enclosure is filled with air and the solid bottom wall, made of pine wood, has finite thickness of t = 0.10L, where L is the length of the bottom wall of the enclosure. Three different cases such as isothermal, linear and sinusoidally varying heating conditions are applied at the bottom of the enclosure to examine the thermal performance and entropy generation inside the enclosure. The governing Navier-Stokes and energy equations are solved using finite element method. Parametric simulation is carried out for a range of Rayleigh number, 103 ≤ Ra ≤ 107 and the visualization of flow and thermal fields is presented through streamline, isotherm and entropy contour plots. The variations of average fluid temperature inside the enclosure, the average Nusselt number along the top of the thick bottom wall and the total entropy generation are also examined in order to ...