基于CFD的水泵水轮机推力轴承润滑性能流固耦合研究

Study on Lubrication Performance and Fluid-Structure Interaction of Pump-Turbine Based on CFD Method

水泵水轮机中推力轴承性能的变化直接影响其承载能力与机组运行稳定性,针对某水泵水轮机推力轴承,本文采用计算流体力学方法,对推力瓦的润滑特性、受力及变形情况进行了流固耦合分析,研究了最小油膜厚度及瓦面倾角对油膜承载力、推力瓦块等效应力及变形的影响。计算结果表明:推力瓦最大等效应力发生在出口处油膜厚度最小的位置,最大应力达到12 MPa,最大变形达到4.16μm;油膜承载力、瓦块等效应力及变形随油膜厚度的增加不断减小,随瓦面倾角的增加先增大后减小。

The change of thrust bearing performance of pump-turbine has a great influence on its bearing capacity and operation stability of unit.The computational fluid dynamics method is used to analyze the force and deformation and the lubrication performance of a pump-turbine thrust tile based on fluid-structure interaction.The influences of minimum oil film thickness and tile surface slop angle on the oil film bearing capacity and the thrust tile equivalent stress and deformation are studied.The results show that,(a)the maximum equivalent stress locates at the position where the oil film thickness is the smallest in the outlet,and the maximum stress is 12 MPa and the maximum deformation is 4.16μm;and(b)the bearing capacity,equivalent stress and deformation decrease with the increase of minimum oil film thickness,and they tend to increase and then decrease with the increase of tile surface slop angle.