Pressure Sensitive Paint Visualization of Pressure Distribution of Externally Pressurized Circular Thrust Gas Bearing With a Single Gas Supply Hole: Experimental Validation of Variation of Pressure Distribution by Supply Pressure

This study investigated the use of pressure sensitive paint (PSP) as new measuring technique for measuring the pressure distribution of a gas bearing. An externally pressurized circular thrust gas bearing with single gas supply hole was used as the test bearing to investigate the suitability of this technique. The test bearing was 30 mm in diameter, with a gas supply hole of diameter 0.7 mm. A coat of PtTFPP, the substance used as the PSP, was applied to the bearing surface using an air-assisted spray. The PSP luminescence characteristics were calibrated before the tests because of their dependency on temperature and pressure. The pressure distribution was obtained by averaging 50 images captured by a 12-bit complementary metal-oxide semiconductor (CMOS) camera. These experimental results were compared with the results of a numerical analysis based on the divergence formulation method. There was good agreement between the experimental and analytical results, thus demonstrating the effectiveness of using PSP for pressure distribution measurements.