不同雷诺数下螺旋槽径向气体轴承承载特性分析

The Load Capacity Properties of Spiral Groove Journal Gas Bearings under Various Reynolds Values

为研究螺旋槽径向气体轴承在不同雷诺数下承载力的变化规律,建立基于Ng-Pan理论修正的气体轴承润滑模型,利用有限差分法求解该模型,得到不同雷诺数下轴承的承载特性,分析轴承几何参数和槽型参数的变化对承载力的影响。结果表明:螺旋槽径向气体轴承在非层流润滑状态下承载力大于层流润滑状态下的承载力;轴承几何参数对承载特性影响显著,其中随偏心率增大承载力呈发散式增大,且非层流状态下承载力与层流状态下承载力差距加大,随长径比增大承载力呈收敛式增加;轴承槽型参数中槽宽比、槽深比对承载特性有明显影响,随槽宽比、槽深比增加轴承承载力增加,而槽数对轴承承载力的影响并不显著,螺旋角对非层流状态下轴承承载力影响较大;轴承进口压力对承载性能有明显影响,随进口压力增大,承载力在层流状态下增加,在非层流状态下波动较大。

To investigate the variation of carrying capacity of a spiral-groove gas radial bearing under different Reynolds numbers,a gas bearing lubrication model modified by Ng-Pan theory was established.The model was solved using the finite difference method to obtain the bearing characteristics under different Reynolds numbers.The effects of geometric parameters and groove parameters on carrying capacity were analyzed.The results show that the carrying capacity of the spiral-groove gas radial bearing in non-laminar lubrication state is greater than that in the laminar lubrication state.The geometric parameters of the bearing have a significant influence on the bearing characteristics.As the eccentricity increases,the bearing capacity increases divergently,and the difference between the bearing capacity in the non-laminar lubrication state and the laminar lubrication state increases.As the aspect ratio increases,the bearing capacity increases convergently.Among the groove parameters,groove width ratio and groove depth ratio have a significant impact on the bearing characteristics,and the bearing bearing capacity increases with the increase of groove width ratio and groove depth ratio.While the influence of the number of grooves on bearing bearing capacity is not significant,and the helix angle only has a significant impact on bearing capacity in non-laminar lubrication state.The inlet pressure of bearing has obvious influence on carrying capacity.As the inlet pressure increases,the bearing capacity increases in laminar lubrication state and fluctuates greatly in non-laminar lubrication state.