Based on the generalized Reynolds model considering mass-conserving boundary condition and Greenwood/Tripp theory, thermo-elastic-hydrodynamic mixed lubrication of main bearings of marine diesel engines is developed considering the effect of pressure and temperature on oil viscosity and density as well as shell deformation. Reynolds equations are solved using finite volume method. Energy equations in film, heat conduction equations in shell and temperature equations of journal are solved using finite difference method. Deformation of shell is calculated by finite element method. Results show that mixed lubrication occurs frequently and the influence of asperity contacting can not be ignored. The method can predict the cavitation by taking into account of filling ratio, journal orbital path and change of pressure gradient. Eight bearings meet the requirement basically, but bearing 4 and bearing 7 need further optimization.%基于质量守恒边界条件的广义Reynolds方程和Greenwood/Tripp接触理论,计入温度、压力对润滑油黏度、密度和轴瓦变形的影响,对船用柴油机主轴承的混合润滑进行了数值分析.其中Reynolds方程用有限体积法求解,油膜能量方程、轴瓦热传导方程和轴颈温度方程等用有限差分法求解,轴瓦变形用有限元法求解.结果表明:周期内发生混合润滑的时刻较为普遍,微凸峰接触影响不可忽略；端泄能量散失占到总能量散失的80％,油膜出口温度作为监控轴承润滑的重要参数比较适宜；引入填充比,结合轴颈中心轨迹和油膜压力梯度变化,能够更加准确地预测轴承的穴蚀发生；8个轴承基本满足设计要求,但4#轴承、7#轴承需要进一步优化.
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