微型涡轮发动机圆锥气体轴承润滑性能研究

Study on Lubrication Performance of Conical Gas Bearings for Micro Turbine Engines

采用CATIA软件建立圆锥气体轴承气膜三维流场模型,对其进行结构体网格划分后导入Fluent软件进行流体力学模拟,得到三维流场的压力及气体流量分布;计算圆锥气体轴承的承载力大小,分析供气压力、气膜厚度、供气孔位置和供气孔直径对轴承性能的影响。研究结果表明:供气孔附近的压力及气体流速最大;供气压力及供气孔直径越大,轴承的承载力及气体流量越大;减小气膜厚度能有效提升轴承承载力且能节省气体消耗量;供气孔位置在一定范围内外移对轴承承载力影响不大,但在接近边缘时会明显降低轴承承载力,同时,供气孔位置的外移还会引起气体消耗量的增加。

The three-dimensional flow field model of conical gas bearing gas film was established by CATIA software,and the structured grid was established.The fluid dynamics simulation was carried out by Fluent software,and the pressure and gas flow distribution of the three-dimensional flow field were obtained.The load-carrying capacity was calculated,and the effects of supply pressure,film thickness,air supply hole position and air supply hole diameter on bearing performance were analyzed.The results show that the pressure and gas flow rate near the air supply hole are the largest,the larger the supply pressure and the diameter of the air supply hole,the higher the load-carrying capacity and gas flow rate of the bearing.The reduction of the film thickness can effectively improve the bearing capacity of the bearing and save gas consumption at the same time.Varying of air supply hole position within a certain range has little effect on the bearing capacity of the bearing,but when the air supply hole is close to the upper edge,the bearing capacity of the bearing will be significantly reduced,and the external displacement of the air supply hole will also cause an increase in gas consumption.