Abstract: During splash lubrication, the distribution of the lubricant flow field inside the secondary transmission gearbox was very complicated. The traditional finite element method was difficult to perform visual simulation analysis. Based on sufficient research and a large number of preliminary calculations, the MPS method was proposed to study the splash lubrication characteristics of the secondary transmission gearbox for rail vehicles. The flow field characteristics of the gearboxes under different input shaft speeds, initial lubricating oil volumes and ambient temperature were analyzed, and the visual calculation of gearbox splash lubrication was realized. The time-domain variation of the number of oil particles at the gear meshing points was analyzed under different operating conditions, and it is found that the number of particles at the meshing points has little relationship with the speed, and was positively correlated with the initial oil volumes. The number of lubricating oil particles in the meshing area is the largest at 40 ℃ and the lubrication effectiveness is the best. The gear churning power losses of the gearbox under various operating conditions were analyzed, and it is found that the gear churning power losses are positively correlated with the input shaft speeds and the initial oil volumes, and negatively correlated with the ambient temperature increment, and both of the relationship is of nonlinear feature.

Key words: splash lubrication, moving particle semi-implicit(MPS) method, flow field characteristic, lubrication characteristic, gear churning power loss

摘要： 飞溅润滑时，二级传动齿轮箱内部润滑油流场分布情况十分复杂，传统有限元方法难以对其进行可视化仿真分析，在模型处理、算法选用、网格划分和计算工作量等方面存在诸多问题。基于充分的调研与大量的前期计算分析，利用移动粒子半隐式（MPS）法对轨道车辆用二级传动齿轮箱的飞溅润滑特性进行研究。分析了不同输入轴转速、初始润滑油油量和环境温度下齿轮箱内部润滑油的流场特性，实现了齿轮箱飞溅润滑的可视化计算；分析了不同工况下齿轮啮合点的油液粒子数时域变化情况，发现啮合处粒子数与转速关系不大，与初始油量成正相关，40 ℃时啮合处滑油粒子数最多，润滑效果最好；分析了各工况的齿轮箱搅油功率损失情况，发现搅油功率损失与输入轴转速和初始滑油油量成正相关，与环境温度的提高成负相关，且均为非线性变化。

关键词: 飞溅润滑, 移动粒子半隐式法, 流场特性, 润滑特性, 搅油功损