渐开线直齿圆柱齿轮非稳态热弹流润滑分析

TRANSIENT THERMOELASTOHY-DRODYNAMIC LUBRICATION ANALYSIS OF AN INVOLUTE SPUR GEAR

应用多重网格技术,不考虑轮齿表面粗糙度的影响,假设润滑剂为牛顿流体,考虑齿轮重合度对轮齿载荷的影响,根据实际轮齿载荷谱简化的轮齿载荷函数,求得了渐开线直齿圆柱齿轮非稳态热弹流润滑问题的完全数值解。结果表明,考虑油膜温升后,温度对轮齿啮入和啮出点的油膜厚度有显著影响。齿轮啮合过程中的最大油膜压力、最高油膜温升和轮齿间摩擦因数最大值都发生在啮合节点附近。在传动比大于1时,齿轮啮合过程中的最小油膜厚度通常在轮齿的初始啮入点。两轮齿间的油膜温升和摩擦因数受滑滚比、卷吸速度和载荷的影响。

A complete numerical solution for the transient thermoelsatohydrodynamic lubrication problem of an involute spur gear is obtained by using simplified multigrid method. The lubricant is assumed to be Newtonian fluid and the surface roughness of gear teeth is ignored. The load is first assumed to be carried by either two pairs of gear teeth or by only one pair. This transition is modelled as a step variation of the load by simplifying the experimental load spectrum. The results show that thermal effects can strongly influence the approach and recess point film thickness. The maximum pressure, the maximum friction coefficient and the highest film temperature all occur in the vicinity of pitch point. The minimum film thickness usually occurs at the approach point except reduction ratio equals to one. The film temperature and the friction coefficient are influenced by the slip ratio, velocities and the load.