柔性机体下船舶柴油机主轴承 TEHD 润滑分析

摘要

To accurately predict the lubrication characteristics of the main bearings of a marine diesel engine, the dimensions of the whole engine block and crankshaft are reduced by component mode synthesis( CMS) modal syn-thesis method.Based on the generalized Reynolds equation under the mass-conservative boundary condition and Greenwood/Tripp asperity theory, the thermo-elastic-hydrodynamic ( TEHD) mixed lubrication model of the main bearings based on the whole flexible engine is built up, which takes account of the temperature effect.The compari-son with the TEHD mixed lubrication model of a single bearing housing show that the computed result of the TEHD lubrication model of the single bearing housing is conservative, while the parameter change is smooth under the whole engine block model condition and is closer to the actual situation.The comparison with elastic-hydrodynamic ( EHD) lubrication that does not take account of the temperature effect for the whole engine block model indicates that EHD model cannot reveal the whole lubrication feature of bearings accurately .The increased calculation time of TEHD lubrication under the whole engine block model condition is also acceptable in comparison with the other two models;therefore the modeling method of this lubrication model has higher application value.%为更加准确地预测船用柴油机主轴承的润滑特性,运用CMS模态综合法缩减整个机体和曲轴,运用基于质量守恒边界条件的广义Reynolds 方程和Greenwood/Tripp接触理论,计入温度影响,建立了基于整个柔性机体下的主轴承热弹性流体动力TEHD混合润滑模型. 与单轴承座下的TEHD混合润滑对比, 单轴承座计算结果偏于保守,而整机体下参数变化平缓,更接近实际. 与整机体模型下的弹性流体动力EHD润滑对比,不计入温度的影响,其计算结果将无法准确反映轴承的整体润滑形貌. 相较于另2种模型,基于柔性整机体下的热弹性流体动力混合润滑TEHD模型计算时间增加可以接受. 显然,该润滑模型的建模方法具有较高的应用价值.