Pressure-Sensitive Paint Measurements on a Rotor Disk Surface at High Speeds

摘要

Measurement of the static-pressure distribution over the surface of a rotor diskwas attempted using pressure sensitive paint (PSP). A uniform stress, high speed rotor disk, fitted with a shock generator, was built, installed and operated at speeds in excess of 20,000 RPM by a Hamilton Standard turbine driven fuel pump. A once per revolution trigger signal was converted to a transistor to transistor logic (TTL) format and used to gate an intensified charged coupled device (CCD) video camera. Multiple low intensity level camera exposures were integrated and captured to produce a single usable image. Ten captured images were averaged to increase the image's signal to noise ratio and the result was used to produce an image ratio with respect to a static reference condition. Finally, a pseudo coloring process was used to develop a color image that related intensities to both temperature and pressure distributions in accordance with the Stern-Volmer relation. Paint stripping and temperature dependence prevented the measurement of pressure at transonic speeds. The test bed facility and acquisition techniques developed here could now be used to overcome those limitations.