Pressure Sensitive Paints in Quantitative Wind Tunnel Studies

Abstract

The pressure sensitive paint intensity and lifetime system (PSP) is an optical measurement technique to investigate absolute pressure fields on model surfaces for basic research in laboratories, industrial wind tunnels or high speed rotating turbomachines. Detailed information and understanding of flow phenomena – in our case, pressure and temperature fields – can be obtained in speed ranges from U8=20m/s up to Ma= 5.0 as well as qualitative and quantitative data. A number of investigations in different speed ranges from low speed flow over transonic to trisonic and cryogenic were realised and compared with conventional techniques like pressure taps, Kulites®, PIV and laser light sheets. Also the influence of errors was checked for system components and several CFD comparisons in connection to numerical calculation models. Various models from the basic configuration as a cropped delta wing up to a complex Airbus A400M half model with all flaps, rudders and shrouds and rotating or oscillating as well as Reynolds number effects on models were investigated. Finally two complete mobile industrial PSP systems are available now for precise measurements and control the CFD theory using these techniques. 1