不同曲轴平衡率下柴油机主轴承润滑特性分析及变壁厚优化设计

Based on the theory of elastohydrodynamic lubrication and multi-body dynamics, the elasto-hydrodynamics lubrication model of the main bearing in a high-power marine diesel engine was established, and the elastic deformation, surface roughness, oil supply characteristics of the main bearing were considered. The method of establishing this lubrication model was verified by experiments. Based on this model, the influence of the crankshaft balance rate on the lubrication performance of the main bearing's minimum oil film thickness, maximum oil film pressure, shaft trajectory, and oil filling rate was analyzed. And the change of the bearing profiles was carried out to reduce the contact pressure on the bearing edge. The results showed that with the increase of the balance rate from 0 to 100%, the average maximum oil film pressure of main bearing decreased by 60%, and the average minimum oil film thickness increased by 5 times, and the eccentricity of axis track decreased. Through the optimized design of the bearing bush, the minimum oil film thickness of main bearing increased by 24%, and the maximum rough contact pressure decreased by 40%, which reduced edge wear.