Abstract:

ESDU 09016 provides a method, based on that of van Driest and Blumer,which enables the required height of roughness elements in a boundary-layer transition band to be estimated from the local boundary-layer displacement or momentum thickness, together with conditions at the edge of the boundary layer. The item is accompanied by a GUI-based program which, when used in conjunction with a coupled integral-boundary-layer aerofoil or wing /body code (e.g. VGK or VFP), permits rapid evaluation of the required roughness height over a range of test conditions. The program also provides the option determine the required roughness height to fix transition on a simple equivalent flat plate.