活塞二阶运动及活塞裙部摩擦的瞬态分析

为分析不同工况下内燃机活塞-缸套系统的摩擦学和动力学行为,本文从内燃机系统动力学分析入手,结合流体润滑方程,建立了考虑系统变惯量影响的活塞二阶运动与摩擦学行为的瞬态分析模型.以某型号单缸机为例,计算和比较了整个启动过程中曲轴转速、二阶运动及摩擦功耗的变化;对比分析了启动时第一周期与稳定运行时某一周期内活塞二阶运动和活塞裙部摩擦学行为的差别.结果表明:该模型可应用于内燃机动力学和摩擦学行为的稳态及瞬态分析.

Transient Analysis of Piston Secondary Motion and Piston Skirt Friction

To better understand the piston secondary motion and tribological behaviors under different operating conditions, this paper presented a coupling model of the piston secondary dynamics and the fluid dynamic lubrication. Effects of the variation in the system inertia were considered in the model to study the transient behavior of piston secondary motion and piston skirt friction and friction loss. The variations of the engine speed, the piston secondary motion and piston skirt friction loss in the startup were simulated. The piston lateral motion and the piston skirt friction force in the startup and in the steady-state were analyzed. Results showed that the model can be applied to transient study the piston secondary motion and the piston skirt tirbological behavior.