Heat Transfer Measurements in Incompressible Turbulent Flat Plate Boundary Layers With Step Wall Temperature Boundary Conditions

Abstract

This paper presents heat transfer data for the case of incompressible turbulent boundary layer flow of air over a smooth flat plate with an unheated starting length followed by a heated region with constant wall temperature. This problem is one of the fundamental problems of convective heat transfer. Under the assumption of incompressible flow with constant fluid properties, the boundary layer momentum and energy equations become uncoupled and, in addition, the energy equation becomes linear. Therefore, the problem of heat transfer in the boundary layer with an arbitrary surface temperature is amenable to solution by superposition. The simplest boundary condition for which solutions can serve as the kernel of this superposition is the step wall temperature. As shown by Reynolds et al. (1958), the heat transfer solution for complicated wall temperature distributions can be reduced to a rather simple quadrature by using superposition with the step wall temperature solution.