Numerical investigation of unsteady transitional boundary layer flows

Abstract

Different numerical models are available for the prediction of laminar-turbulent transition in boundary layer flows. Although these models gained some maturity in the application for steady flows, little is known about the applicability for unsteady problems in a broad frequency and Reynolds number range. This paper will investigate different unsteady transition prediction methods in external aerodynamics. Flow conditions are identified that unambiguously require an unsteady transition prediction and such that are likely to be covered by a quasi-steady approach. This will help to outline the requirements for future unsteady transition models and to trace deficiencies of existing methods.