Effects of Yaw and Roll Angles on Skin Friction Topology on Delta Wings

Abstract

High-resolution skin friction fields in separated flows on delta wings are measured using quantitative global skin friction diagnostics based on luminescent oil visualizations. The effects of the yaw and roll angles on the skin friction topology on delta wings are studied systematically. The topological features like separation and attachment lines and isolated singular points are identified. The conservation law given by the Poincare-Bendixson index formula for the numbers of the isolated singular points and the boundary switch points is used as a general approach to analyze the skin friction topology.