基于混合建模的发动机曲轴模态分析  

Modal Analysis of Engine Crankshaft Based on Hybrid Modeling

作　　者：吕大立 李海龙 景亚兵[1,2] LV Dali;LI Hailong;JING Yabing(Tianjin Internal Combustion Engine Research Institute,Tianjin 300072,China;School of Mechanical Engineering,Tianjin University,Tianjin 300072,China;Siemens Industrial Software (Beijing) Co.,Ltd.,Beijing 100102,China)

机构地区：[1]天津内燃机研究所,天津300072 [2]天津大学机械工程学院,天津300072 [3]西门子工业软件(北京)有限公司,北京100102

出　　处：《车用发动机》2019年第4期47-51,共5页Vehicle Engine

摘　　要：开展了发动机曲轴在自由状态和安装状态下的模态参数识别,发现曲轴的边界条件对模态参数影响较大;研究了曲轴试验模态与仿真模型的混合建模方法,计算得到曲轴在约束状态下的模态结果。研究结果表明,利用混合建模的方式可以将曲轴自由模态结果转换为实际安装状态下的约束模态,以用于评估曲轴实际工作过程的动态特性,同时得到了气缸压力对曲轴约束模态影响较小的结论。混合建模的方式结合了试验和仿真的优点,提高了曲轴约束模态的分析精度,降低了试验限制条件,为评估曲轴动态性能和发动机动力学分析创造了更准确的条件。The identification of modal parameter for engine crankshaft in the free and fixed state was carried out.It was found that the boundary condition of crankshaft had great influence on the modal parameters.The hybrid modeling method of crankshaft test mode and simulation model was studied and the modal results in the constrained mode were acquired.The results show that the hybrid modeling method can convert the free mode results of crankshaft into the constrained mode that corresponds to the real fixed state in order to evaluate the dynamic characteristics of actual crankshaft operating process.In addition,it is confirmed that the in-cylinder pressure has less influence on the crankshaft restraint mode.The hybrid modeling method has the advantages of both experiment and simulation,improves the analysis accuracy of crankshaft constrained mode and reduces the test constraints,which provides more accurate conditions for evaluating the crankshaft dynamic performance and analyzing engine dynamic characteristics.

关 键 词：混合建模 曲轴 自由模态 约束模态 动态特性 

分 类 号：TK423.31[动力工程及工程热物理—动力机械及工程]