The Influence of Taper Inlet Height on the Performance of Gas Thrust Foil Bearing: Simulation and Experiment

doi:10.3901/JME.2021.09.051

Abstract

Abstract: The structure of gas thrust foil bearing is briefly introduced and the theoretical model of thrust bearing is established. The gas Reynolds equation and gas film thickness equation are solved by the coupling of the finite element method and the finite difference method. The relationship between the bearing load capacity and the taper inlet height is obtained by simulation. It is found that there is an optimal taper inlet height to maximize the bearing load capacity. The load capacity increases sharply with the increase of taper inlet height before the optimal taper inlet height, and the load capacity decreases slowly with the taper inlet height after the optimal taper inlet height. The test rig of thrust bearing is built, and each part of the test rig and the test principle are briefly introduced. At the same time, three thrust bearings with different taper inlet heights (20 μm, 70 μm, 114 μm) were manufactured. The limited load capacity measurement was carried out at 15 000 r/min, 21 000 r/min, 25 000 r/min and 28 000 r/min and compared with the simulation results. The results showed that the thrust bearing with taper inlet height of 20 μm performs the best, and the performance of the thrust bearing with taper inlet height of 70 μm and 114 μm has little difference. Therefore, it is very important to choose the appropriate taper inlet during thrust bearing designing and manufacturing.

Key words: gas thrust foil bearing, taper inlet height, load capacity, friction torque, Reynolds equation

CLC Number:

V229
TH133

XU Fangcheng, HOU Liukai, WU Bin, HE Bo. The Influence of Taper Inlet Height on the Performance of Gas Thrust Foil Bearing: Simulation and Experiment[J]. Journal of Mechanical Engineering, 2021, 57(9): 51-60.

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