Theoretical Analysis And Experimental Research On Gas Squeeze Film With Inertial Effect

Gas squeeze film lubrication is a new method of lubrication. The high-frequency vibration of theultrasonic transducer, which is made of piezoceramic material or magnetostrictive material, makes thegas between vibration plate and suspension plate squeezed continually. Then it results in air pressurehigher than atmospheric pressure. It means gas squeeze film has definite levitation capacity. Gassqueeze film bearing is simpler than aerostatic bearing in structure, and superior to aerodynamicbearing at low velocity or static state. Hence, gas squeeze film bearing has a broad applicationprospect. This article makes research on gas squeeze film from theory and experiment.On theoretical aspect, this paper firstly revises the gas squeeze film Reynolds equation with theinfluence of the gas inertia. The modified Reynolds equation is solved with finite difference methodto obtain the pressure and levitation capacity of the gas squeeze film. Through changing differentparameters, it makes some discussion about the influence of gas inertia on the levitation capacity bycompared with the situation without gas inertia. Then, the paper establishes average flow modelwhich contains gas inertia and surface roughness to analyze the influences of different roughness ongas squeeze film, and compare the influences between surface roughness and gas inertia. At last, itanalyzes the gas squeeze film which contains gas inertia and vibration modality of vibration plate.On experimental aspect, a new suspension constraint ring is designed, and the squeeze filmexperiment system is built. Based on this, part of the suspension performances of squeeze film istested. The data acquisition and processing equipments are also selected. Finally, the obtained data areanalyzed in this paper.Theoretical analysis and experimental research have shown that gas inertia, surface roughnessand excitation modes are three important factors that affect the performance of gas squeeze film. Thedecrease function of inertia to gas film pressure mainly reflects in the relative large film thicknessstage, while the increase function of surface roughness mainly reflects in the small film thicknessstage. At the same time, gas inertia will weaken the influence of surface roughness to gas filmpressure. If the vibration modality of vibration plate is put into film thickness equation, the result ofcalculation can be more accurate, and the influence of gas inertia can be reduced to some extent.