基于CFD方法的滑动轴承多相流油膜稳定性分析

Analysis on Multi-Phase Flow Oil Film Stability of Journal Bearing Based on CFD Method

应用计算流体力学方法,使用多相流模型,建立滑动轴承中的油膜模型;计算不同的转速和偏心率下油膜的载荷、最大压力和气化比例,分析它们随转速和偏心率的变化规律;利用该规律说明了实际汽轮发电机组在升速过程中的稳定性的变化。结果表明:在偏心率不变的条件下,随着转速的增加,或在转速不变的条件下,随着偏心率的增加,油膜载荷和最大压力均增加,油膜的气化比例提高,气化面积增加,因此转速过高或过低,偏心率过大或过小都会使油膜的稳定性下降。

The model of multi-phase flow oil film in journal bearing was established with CFD method.The oil film load,maximum pressure and gas-liquid ratio at different rotation speed and eccentric ratio were respectively calculated.The rules of the oil film stability varied with rotation speed and eccentric ratio were obtained and the reasons of these were ana-lyzed.The variation of stability of steam turbine generator unit in accelerating process was illustrated using the rules.The results show that the oil film load and maximum pressure are increased,the ratio and area of vaporization are expanded with increasing rotation speed at constant eccentric ratio condition or with enlarging eccentric ratio at constant speed condition. Consequently,higher rotation speed or larger eccentric ratio will deteriorate the stability of oil film.