Visualization of aerodynamic effects on a double-delta wing aircraft model using Pressure Sensitive Paint (PSP) technique

Visualization of aerodynamic effects on a three-dimensional double-delta wing aircraft model was conducted using an optical pressure measurement system, based on the Pressure Sensitive Paint (PSP) technique, and in addition a laser-light sheet method. The combination of PSP technology with the laser-light sheet method, provides a good understanding of the flow around the wind tunnel model. In recent years, this novel PSP-technology has attracted considerable attention in the aerospace community. The PSP technique can be used to realize absolute pressure measurements on a surface of a model and in addition to evaluate quantitative aerodynamic flow phenomena using a scientific grade camera and image processing techniques. The PSP system was tested in the Transonic Wind Tunnel of the German Aerospace Center in Göttingen (TWG) under real flow conditions. Instantaneous pressure distributions are recorded in almost real-time so that the recognition and analysis of the vortex dynamics on the model surface is possible. Even the vortex breakdown process, as well as the fine structured Kelvin-Helmholtz instabilities and secondary vortex structures, can be detected by this measurement technique.