Surface Pressure Measurements over a Free Flight Object in a Ballistic Range Facility using Two-Color Pressure-Sensitive Paint

The present study focuses on the challenges of capturing surface pressure data on a free-flight object in a ballistic range facility. There are four main challenges: (1) shooting an aerodynamic model in a ballistic range; (2) capturing the free-flight trajectory; (3) capturing luminescent images of the object during the flight; and (4) obtaining the surface pressure distribution from the luminescent images. Prior work has been successful with the first two challenges; this study will focus on methods to overcome the third and fourth challenges using two-color pressure-sensitive paint (PSP). Using two-color PSP allows the implementation of the motion-capturing method, using a reference signal to fix the position of the signal from the PSP. Tests over the course of this campaign have shown an improvement in image quality by reducing image blur; this work presents the results of a test campaign in Tohoku University's ballistic range, showing that PSP can be used to capture the pressure distribution over a test article in free-flight.