热效应对高速圆锥动静压轴承静特性的影响

Influence of Thermal Effect on Static Characteristics of High-speed Conical Hybrid Bearing

为研究热效应对高速圆锥动静压轴承静特性的影响,建立具有深浅腔结构的圆锥动静压轴承的Reynolds方程、能量方程、深腔流量平衡方程及相关控制方程;采用有限元法和有限差分法对其进行离散,运用正系数法则对能量方程系数及常数项的离散系数进行处理,联立求解得到油膜压力分布与温度分布,计算出高速圆锥动静压轴承的静参数,并分析热效应对高速圆锥动静压轴承静特性的影响。结果表明:热效应使高速圆锥动静压轴承油膜压力减小,且转速越大,压力减幅越大,油膜温升越明显;计入热效应后,润滑油黏度降低,引起高速圆锥动静压轴承偏位角增大,轴向、径向承载力减小,端泄流量增大,摩擦力减小,且转速越高变化越显著。

In order to study the influence of thermal effect on the static characteristics of high-speed conical hybrid bearing,the Reynolds equation,energy equation,deep cavity flow balance equation and related control equation of conical hybrid bearing with deep and shallow cavity structure were established.Finite element method and finite difference method were used to discrete the related equations,the positive coefficient rule was applied to deal with the discrete coefficients of the coefficients and constant terms of the energy equation,the oil film pressure distribution and temperature distribution were obtained,and the static parameters of the high-speed conical hybrid bearing were calculated.The influence of thermal effect on static characteristics of high-speed conical hybrid bearing was analyzed.The results show that the thermal effect causes the decrease of oil film pressure of of the high-speed conical hybrid bearing,and the greater the rotating speed is,the greater the pressure reduction is and the more obvious the oil film temperature rise is.After taking into account the thermal effect,the viscosity of lubricating oil is decreased,resulting in the increase of the angle of displacement of the high-speed conical hybrid bearing,the decrease of the axial and radial bearing capacity,the increase the end discharge,the decrease of the friction,and the change is more significant at higher rotating speed.