B311 低温風洞へのLifetime Imaging法の適用可能性

The intensity-based method is a most common technique by which Pressure-Sensitive Paint images can be converted to the surface pressure. However, this method cannot be applied to a cryogenic wind tunnel because the thermal equilibrium condition cannot be achieved when stopping the tunnel to take the wind-off reference image. In the present experiment, we applied the lifetime-based method to a cryogenic wind tunnel to calculate surface pressure from two images obtained during the wind-on condition. In this experiment, the circular-arc bump model sprayed with PtTFPP/PTMSP paint was tested at the JAXA 0.1m Cryogenic Transonic Wind Tunnel using a UV-LED pulse illuminator and a multi-gated CCD camera. As a result, we could succeed in visualizing surface pressure distribution induced by a shock wave on the model by using lifetime PSP imaging method. This result has demonstrated a feasibility of using lifetime imaging method to a cryogenic wind tunnel.