Measuring gas film pressure distribution in gas foil journal bearings utilizing PVDF sensor array

Achieving a comprehensive and accurate understanding of gas film pressure distribution in gas foil journal bearings (GFJBs) necessitates the use of effective measurement techniques. In this study, a methodology based on polyvinylidene fluoride (PVDF) piezoelectric-film sensor technology is introduced and implemented to measure the gas film pressure distribution in GFJBs. The measurement process is conducted on a single-pad GFJB, with PVDF sensor arrays designed, manufactured, and embedded onto the surface of the top foil. Gas film pressure is measured at up to 16 measurement units spanning both the circumferential and axial directions of the top foil. By employing a fitting algorithm, the distribution of gas film pressure is successfully obtained under a rotational speed range of 21 to 30 krpm and a load range of 40 N to 60 N. Furthermore, the gas film pressure distribution in the axial and circumferential directions is determined through the fitting of the measured pressure data. The test results affirm the feasibility of employing a PVDF sensor array for measuring the gas film pressure field of GFJBs.