基于雷诺方程的滑动轴承可靠性虚拟试验方法

A Virtual Test Based on Reynolds Equation for Reliability of Sliding Bearings

针对往复式压缩机主轴承的磨损失效问题,提出一种可靠性虚拟试验方法.基于流体动力润滑理论中的雷诺方程,推导动压油膜的当量刚度;根据胡克定律得到当量弹性模量.利用非线性有限元分析软件ANSYS/LS-DYNA建立虚拟样机模型,采用壳单元模拟润滑油膜的动态特性.通过ANSYS的参数化设计语言APDL,将整个仿真过程编译成宏程序.根据中心复合法设计随机变量的试验样本点,通过更改宏程序实现虚拟样机的随机抽样;分别对每种取样结果进行动态仿真,获得输出响应(油膜比压)数据;根据试验数据,基于响应面方法建立极限状态方程,进行可靠性灵敏度分析,为滑动轴承的设计提供理论依据.

A virtual test of reliability was proposed to solve the wear-out failure problem of the main sliding bearing of reciprocating compressor. Equivalent stiffness was deduced from the Reynolds equation of hydrodynamic lubrication with the equivalent elastic modulus given according to Hooke law. The nonlinear FEA software ANSYSA_~S-DYNA was used to develop the models of virtual prototype with the shell elements used to simulate oil fihn. The whole process of simulation was compiled to be a Macro program by the ANSYS parametric design language （APDL）. Test sampling points of random variables were designed by central composite method and the Macro program was modified to implement the random sampling of virtual prototype. Then, the dynamic simulation was done for each and every sampling result of the prototype to get the output response data, i.e., the specific pressure of oil film. According to the response surface and testing data, an ultimate state equation was given to analyze both the reliability and sensitivity, thus providing a reference for the design of sliding bearings theoretically.