Theoretical analysis and experimental research on characteristics of the lubricating gas film of a planar restrictor in the orifice-throttling effect

When a restrictor is coupled with groove microstructures, the analysis on the flow-field status of the restrictor’s lubricating gas film becomes more difficult, especially in theoretical calculation. In this study, a single-orifice planar restrictor with double-ring-grooves was researched. First, the theoretical mathematical analysis and calculation of the pressure and temperature distributions of the lubricating gas film, were conducted based on the proposed analysis method of proportional assignation and resynthesis (PAR) along with the finite difference method. Then, the computational fluid dynamics (CFD) simulations based on the simple model were conducted, the results of which show the agreement with the theoretical analysis. Finally and more importantly, experiments were carried out well by using a self-made micro-flow field parameter measurement device (MFFPMD), which verifies the theoretical calculation and the CFD simulation results. The PAR method can be applied in other structures of restrictors, and the experimental study could facilitate the research of the stability of the lubricating gas film.