Transition detection by means of temperature sensitive paint (TSP)

Abstract

A method for detecting the laminar-turbulent boundary layer transition. Surface temperature distributions and heat transfer on test bodies can be determined with the help of temperature-sensitive paint (TSP), which is a well known method for two-dimensional temperature measurement. A specific measurement technique based on the use of TSP enables us to visualize the laminar-to-turbulent boundary-layer transition on wind tunnel models. This is of great interest for high Reynolds number wind tunnel testing which is nowadays mostly carried out in modern, cryogenic wind tunnels like the European-Transonic Windtunnel (ETW). Transition detection by means of TSP has been used with great success by the Institute of Aerodynamics and Flow Technology since the beginning of 2003. Further application fields of TSP are surface temperature measurements in general as an alternative to IR cameras or in areas where the IR camera technique can not be used.