高速油气润滑径向轴承空化流热流体动压分析

A Thermohydrodynamic analysis of Cavitation Flow with Oil Aeration Iubrication in High Speed Bearing

研究了滑动轴承的空化流润滑状态,导出了考虑界面效应的空化流广义Reynolds方程,建立了高速油气润滑径向轴承空化流热流体动压模型。通过数值耦合求解广义Reynolds方程、能量方程和气泡力平衡方程,获得了油气润滑动轴承的压力分布、空化流速分布、气泡速度分布和温升。结果表明:气泡尺寸分布和界面效应将使油膜发散区产生正压力,油气润滑的散热性能明显优于纯油润滑。

Cavitation flow lubrication state for journal bearing under high speed working condi- tion was research in this paper . The generalized Reynolds equation is derived,a thermohydro- dynamic （THD） oil aeration lubrication model is established. In numerical algorithm, a cou- pling strategy is applied in solving both the generalized Reynolds equation and force equilibrium equation of bubble. The good behavior of the proposed algorithm is illustrated in one example of a dynamically loaded journal bearing, and the pressure distribution, the turbulent velocity distribution, bubble velocity distribution and temperature rise were obtained. A comparison with the available experimental results reveals that the bearing capacity and the temperature rise are fairly well predicted by the present model. The results also show that the bubble size distribution and interface effect will generate positive pressure in oil film diverged area, and oil aeration lubrication performance of heat dissipation is superior to pure oil lubrication.