GLOBAL SKIN FRICTION DIAGNOSTICS IN SEPARATED FLOWS USING LUMINESCENT OIL

Abstract

Quantitative skin friction diagnostics in complex separated flows is achieved by using a global luminescent oil-film skin-friction meter. This technique is based on the variational solution for the projected thin-oil-film equation on the image plane. Normalized skin friction fields are obtained in junction flows and flows over surface roughness elements, a double-delta wing, and a low-aspect-ratio rectangular wing. The results show the detailed topological structures of skin friction fields in these flows.