Numerical calculation of convective heat transfer coefficients in an enclosure heated from vertical walls

Abstract

Extensive studies of natural convection problems in enclosures have been published in the literature. Convective heat transfer coefficients of vertical walls of real-size rooms significantly influence thermal comfort and energy economics in buildings. This study is a preliminary numerical investigation of an experimental solution of a real room's natural convection problems. A 2.78 by 2.30 by 2.78 m room that had been both experimental and computationally studied previously has been modeled, and boundary conditions have been defined. As in some other studies, one wall was heated with a constant heat flux and the opposite wall was cooled to resemble a real room's heat loss. The boundary conditions of the heated/cooled walls were first defined as 200 W/m2 heat flux and 0°C constant temperature, respectively, while the other walls were kept adiabatic. The resulting heat transfer coefficients of the hot wall at different wall thermal conditions, floor sizes, room heights, and surface emissivities have been calculated and, the effects of these parameters on convective heat transfer coefficient have been determined and compared with those documented in the literature