大型重载推力轴承热弹流计算及尺寸效应

Thermoelastohydrodynamics Analysis and Size Effect of Large Heavy Thrust Bearing

针对考虑热弹变形的大型重载推力轴承性能预测和尺寸效应问题,对某大型重载推力轴承进行热弹流计算,研究轴承性能随极端载荷与尺寸的变化规律。介绍可倾瓦推力轴承热弹流模型的基本方程,通过计算得到不同尺寸和比压下的轴承性能数据,讨论大型重载轴承的尺寸效应。结果表明:案例轴承瓦块最高油膜压力应远离瓦尖,靠近瓦块支点,该设计有利于压力分布均匀而提高承载力;对于大尺寸推力轴承,由于变形的影响,当载荷超过某一限制值后,轴承性能会随着载荷的稍微增加而发生剧烈变化,甚至导致烧瓦失效。为了避免该现象出现,推力轴承设计时应该进行最大许用比压校核;对于大型重载,还需进行瓦块弹性支撑或平衡梁等均载结构设计。

In order to solve problems of performance prediction considering thermoelastic deformation and size effect of large heavy thrust bearing,the performance variation of thrust bearing with extreme loads and sizes was studied through thermoelastohydrodynamic calculation of thrust bearing. The thermoelastohydrodynamic model basic equations of tilting pad thrust bearing were introduced. The bearing performance data under different size and specific pressure were obtained, and the size effect of large heavy thrust bearing was discussed. The results show that,the maximum film pressure should stay away from the tile tip,and close to the fulcrum. This helps to make the pressure uniform distribution and improve the bearing capacity. Due to the impact of the deformation,when the load exceeds a certain limit values,large heavy bearing performance will increase violently as the load changes slightly,even lead to burnt failure. To avoid this phenomenon,the maximum allowable specific pressure of thrust bearing should be checked,and the design of elastic support or balance beam for heavy load bearings is needed.