25.2 L柴油机摇臂的仿真分析与优化

Simulation and optimization of a 25.2 L diesel engine rocker

为了分析某25.2 L柴油机摇臂断裂的原因,借助Abaqus和FEMFAT有限元分析软件,对柴油机摇臂组件在运行工况下的结构应力及高周疲劳进行分析,并对摇臂危险区域进行优化后再次进行仿真分析,直到摇臂满足设计要求。结果表明:考虑装配过盈力时摇臂的峰值应力比未考虑过盈力时高10.6%,考虑装配过盈力时仿真结果与试验结果相吻合;直角卸油槽为摇臂局部薄弱区域,使用圆弧形卸油槽代替直角卸油槽能有效降低局部应力集中;优化后摇臂峰值应力降低17.5%,摇臂抗疲劳性能得到提升。

The cause of broken happened on a 25.2 L diesel engine rocker was conducted,while Abaqus and FEMFAT finite element analysis softwares were used to analyze the structural stress and high cycle fatigue of diesel engine rocker components under working conditions,and the dangerous areas of the rocker were optimized and simulated until reaching the design standard.The results show that the peak stress of rocker with assembly interference force is 10.6%higher than that without assembly interference force,and the simulation results are consistent with the test results when assembly interference force is considered.The right-angle oil unloading groove is the local weak area of the rocker.Using the arc-shaped oil unloading groove instead of the right-angle oil unloading groove can effectively reduce the local stress concentration.After optimization,the peak stress of the rocker is reduced by 17.5%,and the fatigue performance of the rocker is improved.