New evolution equations for turbulent boundary layers in arbitrary pressure gradients

A new approach to the classical closure problem for turbulent boundary laye rs is presented. This involves using the well-known mean-flow scaling lau's such as Prandtl's law of the wall and the law of the wake of Coles togethe r with the mean continuity and the mean momentum differential and integral equations. The important parameters governing the flow in the general non-e quilibrium case are identified and are used for establishing a framework fo r closure. Initially, closure is done here empirically from the data but th e framework is most suitable for applying the attached eddy hypothesis in f uture work. How this might be done is indicated here.