Time-resolved pressure measurements by means of PSP in cryogenic conditions

The capability of the Pressure-Sensitive Paint (PSP) method for application in unsteady flows in cryogenic wind tunnels was investigated by carrying out experiments in the Cryogenic Ludwieg-Tube Göttingen (KRG). The 2D airfoil model (LV2F) was coated with PtTFPP/PTMSP paint and tested in a nitrogen atmosphere between 120 – 283 K. PSP and pressure tap data were acquired at different Mach and Reynolds number. The oxygen concentration of the flow was set to approx. 1000 ppm by preconditioning supplying dry air. As a result, the intensity-based PSP method successfully measured the pressure distribution on the airfoil model under cryogenic conditions and clearly the expected shock oscillation could be detected and resolved by means of PSP. Therefore, it can be concluded that the PSP method was successfully applied under cryogenic conditions to detect unsteady flow phenomena