气穴对滑动轴承摩擦学性能影响的CFD分析

Study on the effect of cavitation on tribological performances of sliding bearing by CFD Method

气穴对滑动轴承性能影响一直为人们所关注,而传统的分析方法不能真实刻画气穴的作用。为寻求合理的气穴研究方法,并由之改进轴承的摩擦学性能,基于计算流体动力学(CFD)与Rayleigh-Plesset(PRE)气穴理论,应用商业软件ANSYS中CFX模块分析了气穴现象对滑动轴承摩擦性能的影响。结果表明:随着偏心率、宽径比和转速的增加,考虑气穴模型后气穴现象会降低润滑剂粘度,轴承油膜的摩擦力和摩擦系数会减小;随着偏心率、宽径比和转速的增加,润滑剂的平均气化率变大。

Much attention has been paid to the influence of cavitation on the performance of a sliding bearing,but conventional analysis methods can not exactly describe the influence.Therefore,a reasonable cavitation method is desired,with which tribological performances of the bearing can be improved.Based on the computational fluid dynamics（CFD）and Rayleigh-Plesset（PRE）model,the influence of cavitation is studied by the commercial software CFX module.The numerical results show that both the friction force and the friction coefficient decrease,compared with the corresponding results without the consideration of cavitation effect,which is caused by the reduce in the lubricant viscosity due to the cavitation effect.With the increases in the eccentricity ratio,width diameter ratio and rotating speed,the mean vaporization ratio becomes severer.