Using cryoTSP as a tool for transition detection and instability examination at high Reynolds numbers

Abstract

Transition detection in ‘warm’ wind tunnels can be realized using commercially available IR cameras. In cryogenic testing, IR imaging becomes more difficult because of the reduction in radiated energy and the shift to longer wavelengths. At low cryogenic temperatures (say T = 110K) it is difficult to get meaningful results, and the use of helium cooled (very sophisticated) IR cameras is necessary. On the other hand, custom-built temperature sensitive paint for cryogenic testing (cryoTSP) still works well for the purpose of transition detection at low temperatures, i.e. in cryogenic wind tunnels.