Evaluation of Lifetime-based Pressure-Sensitive Paint Measurement in Low-speed Flow

The lifetime-based method has been applied to Pressure-Sensitive Paint (PSP) measurement in low-speed flow. Based on theoretical considerations and sample tests, a method to calculate pressure using "a-priori" method was proposed. In this method, pressure is related to the ratio of the luminescent intensity ratios obtained at two different gates between the wind-on and wind-off conditions, multiplied by a correction factor calculated from the single-point measurement of model substrate temperature. In order to evaluate the effectiveness of this method, a simplified car model was tested in a low-speed wind tunnel. It was shown that the effects of non-uniform distributions of lifetime and temperature could be cancelled out by the present method. The result obtained by the lifetime method was in good agreement with those of pressure taps and the intensity method.