The Development and Application of Two-Color Pressure-Sensitive Paint in Jet Impingement Experiments

Abstract

This study aimed to develop a two-color pressure-sensitive paint (PSP) that has both high pressure sensitivity and high temperature sensitivity. Different nitrobenzoxadiazole (NBD) derivatives were used as the temperature probe. Among them, NBD-ZY37 demonstrated favorable stability against photodegradation, and its temperature sensitivity in an RTV118-based two-color PSP was −1.4%/°C. Moreover, temperature sensitivity was independent of pressure in the tested temperature range. PtTFPP was used, and its pressure sensitivity was measured to be 0.5% per kPa. The two-color PSP paint underwent further examination in jet impingement experiments. The experimental results indicated that the pressure fluctuation introduced by the shock waves occurred earlier at higher impingement angles. Specifically, when the pressure ratio was 2.38, increasing the impinging angle from 15° to 30° caused the location of the pressure wave to move from s/D at 0.8 to the exit of the nozzle. Simultaneously, the shape of the maximum pressure zone changed from a fan shape to a round shape. Additionally, the jet region expanded when the pressure ratio was increased.

Keywords

• pressure-sensitive paint
• two-color PSP
• temperature correction
• jet impingement