瞬变载荷作用下滑动轴承轴心轨迹计算仿真

Simulation of Journal Centre Trajectories of Hydrodynamic Journal Bearing Under Transient Loads

为了研究动压滑动轴承在瞬变载荷作用下的润滑状况,在考虑轴颈惯性力和非线性油膜力的基础上,建立了滑动轴承轴心轨迹的运动方程,提出了采用欧拉法求解有限长滑动轴承瞬时轴心轨迹的数值方法。分别计算了在阶跃、矩形脉冲和正弦脉冲瞬变载荷作用下轴心轨迹、最大油膜压力及最小油膜厚度的变化规律。分析结果表明,在瞬变载荷作用时,轴心轨迹、最大油膜压力及最小油膜厚度都有较大的变化并呈现出一定的振荡过程。由于脉冲载荷的作用时间有限,随着其消失,轴心乃收敛于原平衡位置,而阶跃载荷则使轴心收敛于新的平衡位置。

This paper attempts to study the lubrication property of a hydrodynamic journal bearing under transient loads.Nonlinear equations of motion for the rotor-bearing system considering the journal inertia effects were established.A computational method using the Euler scheme was put forward to determine the transient journal centre trajectories of the bearing.Three kinds of dynamic loads were imposed on the shaft:step loads,rectangular pulse loads and sinusoidal impulse loads.The laws of the journal centre trajectories,the maximum film pressure and the minimum film thickness varying with the loads were obtained.The results show that under the transient loads,the centre trajectories,the maximum film pressure and the minimum film thickness change in large ranges with a certain degree of oscillation process.As the time-limited pulse load attenuates the journal center trajectory converges on the original equilibrium position,while the step load makes the journal center converge on a new equilibrium position.