Temperature- and pressure-sensitive paint measurements in short-duration hypersonic flow

Surface temperatures and pressures were measured on an elliptic cone lifting body in a hypersonic flowfield using thin-film (similar to5 mum) temperature- and pressure-sensitive paints (TSPs and PSPs), The tests were conducted in the 48-inch hypersonic shock tunnel (48-inch HST) at Calspan-University of Buffalo Research Center and were part of a more comprehensive experimental study examining the three-dimensional characteristics of laminar, transitional, and turbulent flow over the model. Measurement opportunity in the 48-inch HST was limited by the short duration of steady freestream conditions of the driven gas; image acquisition times were similar to3 ms. Images of the coatings applied to the broad side of the symmetric elliptic cone were calibrated with in situ static pressure and surface-film temperature measurements. The TSP results illustrate the higher heat transfer rates and change in boundary-layer transition over the model surface caused by the nose geometry, and the PSP results show a mild pressure gradient over the interrogated surface region. Submillisecond TSP acquisition using a high-speed imager demonstrated the feasibility of measuring the surface temperature rise.