平箔片楔形高度对气体止推箔片轴承特性影响

针对波箔型气体止推箔片轴承，建立了箔片结构二维薄板模型，并通过有限差分法和有限元法耦合求解可压缩气体Reynolds方程和气膜厚度方程，获得了给定轴承载荷条件下轴承气膜压力分布、气膜厚度分布、平箔片变形量和功率损耗等轴承特性.通过对比楔形高度分别为25，70，100，200，300μm时的轴承特性仿真结果研究了楔形高度对轴承性能的影响.结果表明:降低楔形高度使轴承气膜压力分布更均匀，并降低了平箔片的局部集中载荷.但楔形高度存在一个最佳值，使得达到相同轴承载荷所需的最小气膜厚度最大，并且轴承具有最小功率损耗，提高了轴承的工作效率.该结果为气体止推箔片轴承的结构设计提供的理论参考. 

Performance analysis of air foil thrust bearings withdifferent top foil taper heights

The foil structural 2-D thin plate model of bump type air foil thrust bearing was created, finite difference method (FDM) and finite element method (FEM) were coupled together to solve the compressible air Reynolds equation and film thickness equation. The bearing performance such as pressure distribution, film thickness, top foil deformation and power loss were obtained in specific bearing load condition, and the effects of taper height on bearing performance were studied by comparing simulation results with 25, 70, 100, 200, 300μm taper heights. The results show that reducing taper height can make pressure distribution more uniform and reduce the concentrated force on top foil. However, with an optimum value, the bearing can maximize the minimum film thickness for the required same load capacity. Also the bearing can realize the lowest power loss, and the bearing efficiency is improved. These results can be treated as a guideline of air foil thrust bearing design.