界面滑移对动压气体轴承间隙流动特性的影响*

为揭示转子静子表面流固界面非一致滑移状态下动压气体轴承转静子间隙流动机制以及对轴承性能的影响，建立界面非一致滑移修正雷诺方程，并耦合气膜厚度方程进行超松弛迭代求解，数值分析研究转静侧滑移状态、偏心率、间隙尺寸和耦合弹性箔片对间隙气膜流动特性的影响。结果表明：流固界面滑移状态对转静子间隙流动及其轴承性能具有显著的影响；转子侧滑移发生在压力上升区，这使得高压区压力减小；而静子侧滑移发生在压力下降区，使得高压区压力增大；与无滑移情形相比，局部滑移时间隙气膜压力峰值变化增幅达12%。在研究的参数范围内，随着偏心率减小和间隙高度增大，间隙界面滑移状态逐渐由转子侧滑移占主导向静子侧滑移占主导转变；耦合弹性箔片时，滑移区域增大1~4倍，滑移速度增大2~8倍，间隙气膜压力呈现双峰值分布。

Flow Characteristics of Dynamic Pressure Gas Bearing with Interface Slip

In order to reveal the flow mechanism of the dynamic pressure gas bearing under the partial slip state and the effect on the bearing performance,the modified Reynolds equation considering the partial slip was established and solved with over relaxation iteration by coupling film thickness equation.The effects of slip state,eccentricity,gap size and coupled elastic foil on the gap film flow characteristics were numerically analyzed.The results show that the slip state of the fluid-solid interface has a significant effect on the rotor and stator gap flow and the bearing performance.Rotor side slip occurs in the pressure rise zone,which reduces the pressure in the high pressure zone.The stator side slip occurs in the pressure drop zone,which increases the pressure in the high pressure zone.Compared with the case of no slip,the interstitial gas film pressure peak value is increased by 12% during local slip.Within the parameters of this paper,as the eccentricity decreases and the gap height increases,the slip state of the gap interface gradually changes from the dominant rotor side slip to the dominant stator side slip.When the elastic foil is coupled,the slip area is increased by 1 to 4 times,the slip speed is increased by 2 to 8 times,and the gap gas film pressure presents a double peak distribution.