发动机曲轴多体动力学仿真分析

Multi-body Dynamics Simulation Analysis of Engine Crankshaft

研究国内某直列四缸发动机曲轴,采用非线性多体动力学理论对该曲轴进行了受力分析。利用多体动力学软件AVL EXCITE PU,建立曲轴仿真模型,并对曲轴主轴承进行动力学分析及计算。运用这种仿真方法能够在较短时间内分析得到最为接近曲轴实际工况中发生的结构变化,根据对曲轴的自由模态、气压力矩的频谱范围、位移变化曲线以及曲轴在一个工作循环内的应力变化情况等仿真结果的分析得出曲轴结构的薄弱区域,以达到快速找到薄弱区域并对其进行优化的目的,同时也为后期轴承结构设计提供了依据。

The nonlinear multi-body dynamics theory was used to analyze the main bearing of an inline four-cylinder engine crankshaft. The crankshaft simulation model was established by using the multi-body dynamics software（AVL EXCITE PU）,and the kinetic analysis and calculation were carried out for the crankshaft model. Using this simulation method can be analyzed in a relatively short period of time to get closer to the crankshaft in the actual conditions of the structure of the deformation and stress changes.Based on the analysis of the simulation results of the free mode of the crankshaft,the spectral range of the pressure moment,the displacement curve and the stress change of the crankshaft in a working cycle,the weak region of the crankshaft structure is found. In order to quickly find the weak area and optimize its purpose,but also for the late bearing structure design provides the basis.