Natural Convection Heat Transfer in an Asymmetrically Heated Vertical Channel Controlled by Through Flows

Abstract

The effort to solve the fundamental problem of convective flows and heat transfer in a vertical channel is continued in this work, considering a new control parameter for the thermal flow regime. A numerical investigation of the developing heat convection in the channel is presented, while considering the effects of a vertical forced flow on the Nusselt number at the cold wall for a wide range of related parameters. By the analysis of these results, it is possible to predict heat transfer behavior especially in cases when the Nusselt number at the cold wall becomes practically zero. The main results obtained from this study are the critical Reynolds number variation obtained for different geometrical aspect ratios(A=H / L=2;4;8;16)and the natural convection parameter, Ra=10⁴-10⁷. Based on the scaling analysis it is determined that the critical Reynolds number is independent of Ra and scaled as R^HT_ecr∝A², where A is the aspect ratio.