An Aspect of Heat Transfer in Accelerating Turbulent Boundary Layers

Abstract

Theoretical consideration indicates that, in an accelerated turbulent flow, the thermal boundary layer may penetrate significantly beyond the edge of the velocity boundary layer. This effect may contribute in part to the marked decrease in Stanton number which has been reported in accelerated turbulent boundary layers. This paper presents theoretical solutions to turbulent velocity and thermal boundary layers in flow between converging planes where the wall temperature varies as the free-stream velocity raised to a positive exponent. The solutions clearly illustrate that, as the wall-temperature variation is made less rapid, the thermal boundary layer penetrates progressively further beyond the velocity boundary layer, causing the Stanton number to decrease.