高速发动机油膜惯性对活塞裙润滑影响

利用一种新的迭代算法 ,分析了高速发动机油膜惯性对活塞裙润滑特性的影响 .该迭代方法是利用有限元法和差分法交替求解Navier Stocks方程和雷诺方程 ,据此导出了适用于高速发动机活塞裙的润滑计算的混和润滑雷诺模型 .新的模型借助惯性系数 ,引入了油膜惯性项 ;同时给出求解含有油膜惯性项的迭代步骤和有限元表达式。计算结果表明 :随着惯性系数和活塞裙的长径比的不同 ,油膜惯性会对油膜的摩擦力、压力和承载力产生不同的影响 ,这种影响对承载力尤为明显 .该润滑模型也可用于中、低速发动机的活塞裙润滑计算以及不计入惯性项 (惯性系数置为零 )的某些润滑问题求解 .

Research on Effect of Oil Film Inertia on Piston Skirt by Iteration Method

The influence of oil film inertia on piston skirt lubrication in a high speed engine is investigated by an iteration method that alternately solves the Navier-Stocks equations and the Reynolds equation by finite element method and difference method. The Reynolds lubrication equation including oil film inertia is developed, in which the inertia coefficient is introduced to investigate the effect of oil film inertia. The iteration procedure and finite formulation of solving the new Reynolds lubrication equation are given to analyze the effect of oil film on piston skirt in this kind of engine. The calculation results show that the oil film inertia has some effects on the friction force, pressure force and load capacity of oil film and its effect is obvious for the last. The Reynolds lubrication equation proposed can be also used to analyze the lubrication performance of the piston skirt in low or medium speed engine and some other lubrication problems generally excluding oil film inertia with the inertia coefficient being set at zero.