纯挤压弹流油膜对球面滚子简谐振动的响应

The Response of Pure Squeeze EHL Film to the Harmonic Vibration of a Spherical Roller

应用多重网格技术求解椭圆接触简谐振动球面滚子与无限大平面之间的弹性流体动力润滑问题,得到一组典型的数值解,并在该解的基础上分析不同的平衡位置、振幅和频率对中心压力和中心膜厚的影响。结果表明:在整个挤压反弹过程中,中心压力和中心膜厚随时间的变化曲线与稳态弹流润滑的压力和膜厚在空间上的变化曲线具有类似的特征,尤其是反弹阶段会出现较高的第二压力峰。经分析可知,该压力峰是由于反弹的最后阶段接触区中心处的凹坑消失,从而产生强烈的局部挤压效应所致。另外,结果显示,平衡位置的增大会缩短纯挤压的时间并减小中心压力的主峰高度,但会增加第二压力峰的高度,而振幅和频率的增加都会使纯挤压效应变得更强。

Multi-grid techniques were employed to solve the pure-squeeze elastohydrodynamic lubrication （EHL）problem in elliptic contact between a harmonically vibrating spherical roller and an infinite plane, and a numerical solution was obtained for a typical case. On the basis of this solution, the influence of the balance position, the vibration amplitude and the vibration frequency on the central pressure and central film thickness was analyzed. The results indicate that, in the whole process of squeeze and rebound, the variation curves of the central pressure and central film thickness versus time are very similar to the spatial curves of pressure and film thickness in a steady-state EHL contact. Especially,it was found that the central pressure curve also has a spike in the rebounding stage of the pure-squeeze process due to the disappearance of the central dimple, which results in a very significant local squeeze action in the final period in the rebounding process. The results show also that, as the increase in the balance position, both the time of the effective pure-squeeze action and the height of the main pressure peak are reduced, however, the height of the time-spike is enhanced. Furthermore, as the increases in both the vibration amplitude and frequency, the pure-squeeze action becomes much stronger.