径向滑动轴承中流体从层流到紊流的流动分析和转变判据研究

THE RESEARCH OF FLUID FLOW AND FLOW TRANSITION CRITERIA FROM LAMINAR TO TURBULENT IN A JOURNAL BEARING

本文推导了有限长圆柱轴承油膜流体流动的约束方程和固壁上的压力边条,用原始变量法直接求解了三维完全的N-S方程,计算分析了有限长圆柱轴承中油膜层流失稳的临界Taylor数、流场、压力场和摩擦阻力,并通过实验对临界Taylor数进行了验证,结果表明,在有限长轴承中,随着转速的提高,摩擦阻力线性增加,层流失稳出现的涡动将增加摩擦阻力,随着偏心率的增加,层流失稳的临界转速将提高.

The governing equations of fluid flow in finite length cylindrical journal bearing and the boundary conditions of pressure are derived in this paper, and the primitive variable method is used to solve the complete 3-dimensional N-S equations. The critical Taylor number for onset of instability of fluid film laminar flow, velocity, film pressure and frictional force of bearing are calculated and the critical Taylor number calculated in this paper is verified by experiment. The results show that frictional force of bering increases linearly as velocity increases, the vortical flow increases the frictional force of bearing, and the critical Taylor number increases with the increasing of eccentricity.