Asymptotic solutions for supersonic laminar flow past steps and bases

The problem of laminar supersonic flow over backward-facing steps of small height has been formulated as a triple-deck interaction relationship. A quasi-unsteady finite difference algorithm was derived which provides plausible solutions for a range of values of the rescaled step height H. It was found that as H approaches zero, a substructure emerges within the lower deck, consisting of a small-H inner region imbedded within the lower deck. Analytic solutions are available which are applicable outside this small-H inner region for the first-order step and the zeroth-order problems.