Determination of Transfer Function of Pressure-Sensitive Paint

Abstract

An experimental setup for detailed and accurate experimental determination of the frequency response of pressure-sensitive paints (PSP) is presented. By use of a mechanical shaker which is connected to a pressure chamber the setup realizes high-quality sinusoidal pressure variations for frequencies ranging from less than 0.1 Hz up to several hundreds of Hz with pressure amplitudes up to ±3 kPa. An appropriate optical system for detection of luminescent light of the PSP has been adapted for the experimental set-up. Unsteady characterization of various formulations of PSP based on the luminophore platinum tetra (pentafluorophenyl)porphine (PtTFPP) in a fluoroacrylic polymer was carried out for frequencies f = 0.1 up to 120 Hz. The influence on frequency response from paint layer thickness was measured. The influence of paint porosity is tested by adding from 0 to 80 mass % TiO2 particles to the PSP. The frequency response is shown to be similar with respect to a characteristic time, which ranged from the order of seconds for no filler to the order of milliseconds for higher amount of TiO2.