Temperature-Compensated Fast Pressure-Sensitive Paint

This paper describes the development of a two-color fast-responding pressure-sensitive paint with temperature correction capability. This paint uses a platinum porphyrin compound as the pressure sensor with perylene as the reference sensor and a laser dye added to adjust the spectrum distribution and temperature sensitivity of the reference channel. Separate emission signals of the pressure and reference sensors can be captured by the red and green channels of a color camera, respectively. Temperature errors are counteracted by taking a ratio of ratios, whereas a correction parameter is introduced to compensate for the difference in temperature sensitivity of the two separate emissions. The green channel also has the potential to correct for illumination changes caused by model movement and deformation in a nonuniform illumination field, provided that there is no temperature change during the test, or the temperature change can be measured separately. This paint is fast enough to resolve pressure changes occurring at several kilohertz due to the high diffusivity of the porous polymer/ceramic binder.