温黏热效应对圆锥动静压浮环轴承润滑承载特性影响分析

Temperature-viscosity thermal effect on lubrication load carrying characteristics for a conical hydrodynamic/hydrostatic floating ring bearing

为研究润滑油温黏热效应对圆锥动静压浮环轴承性能的影响,构建内、外膜热流体润滑控制方程组,采用有限元法和有限差分法耦合求解Reynolds方程、能量方程、温黏关系式及浮环平衡方程,结合轴承温度测量试验获得油膜温度场分布特征,分析不同转速、偏心率工况下轴承承载力、摩擦力矩、端泄流量等润滑承载特性的变化规律,揭示温黏热效应对最小油膜厚度的影响。结果表明:油膜温度场不均匀分布现象明显,深腔与进油槽油膜温度较低,封油面附近油温迅速升高;温黏热效应使轴承在高转速下的承载能力下降,端泄流量增加;内外层最小油膜厚度随进油温度的升高而减小,为避免承载力下降引起局部油膜破裂及润滑失效,有必要在轴承设计分析阶段考虑温黏热效应的影响。

Here,to study the effect of lubricating oil temperature-viscosity-thermal effect on performance of conical hydrodynamic-hydrostatic floating ring bearing,a set of inner and outer membrane thermal fluid lubrication governing equations was established.Interaction of finite element method and finite difference method was used to solve Reynolds equation,energy equation,temperature-viscosity relation equation and floating ring balance equation.Combined with bearing temperature measurement experiments,distribution characteristics of oil film temperature field were obtained to analyze changes in lubrication load-bearing characteristics of load-bearing capacity,friction torque and end leakage flow rate under different rotating speed and eccentricity conditions,and reveal influences of temperature-viscosity-thermal effect on minimum oil film thickness.The results showed that uneven distribution of oil film temperature field is obvious,oil film temperatures in deep cavity and oil inlet groove are lower,oil temperature near sealing oil surface rises rapidly;temperature-viscosity-thermal effect reduces load-bearing capacity of floating ring bearing at high rotating speed and increases end leakage flow rate;minimum oil film thickness of inner and outer layers decreases with increase in oil inlet temperature,to avoid local oil film rupture and lubrication failure caused by decrease in load-bearing capacity,it is necessary to consider influences of temperature-viscosity-thermal effect in bearing design and analysis stage.