Transition Detection on High-Lift devices in DNW-KKK by means of Temperature-Sensitive Paint

Abstract

Temperature-Sensitive Paint (TSP) allows detection of laminar-to-turbulent boundary layer transition on the complete visible aircraft model surface in high spatial resolution. This non-intrusive observation technique visualizes temperature differences caused by different convection heat transfer coefficients in the laminar and turbulent part of a boundary layer. In “warm” wind tunnels, IR cameras are used as a transition detection tool for a long time. But it is very difficult to apply IR technique at temperatures of less than 200 K. In addition, the spatial resolution of obtained IR camera image is very limited. Therefore, TSP technique is important for a cryogenic wind tunnel.