On compressible turbulent boundary layers in the presence of favorable pressure gradients

A general theory is developed for heat transfer, friction, and displacement thicknesses generated by compressible turbulent boundary layers in the presence of arbitrary favorable pressure gradients. The framework of the analysis is developed upon well-established basic results for incompressible flows and extended to compressible situations by means of compressibility transformations. The scheme is to start with a small number of basic suppositions and then to deduce subsequent results by means of rational analysis, with a minimum number of ad hoc insertions. The influence of the pressure gradient on the heat-transfer law, or Reynolds-analogy parameter, is of prime interest. The emphasis is on approximate analytic results that lead to understanding and wide practical utility. Some interesting predictions of the theory are discussed, such as transition from turbulent to laminar-like conditions.