一款不带平衡轴三缸发动机车型怠速抖动问题研究  

Research on Idle Shake Problem of a Three-cylinder Engine without Balance Shaft

作　　者：田小彦 李文浩 TIAN Xiaoyan;LI Wenhao

机构地区：[1]上汽集团创新研究开发总院,上海201804

出　　处：《上海汽车》2023年第4期16-20,共5页Shanghai Auto

摘　　要：某不带平衡轴的三缸发动机乘用车型在开发过程中出现了怠速抖动问题,降低了整车的NVH品质。文章通过曲柄连杆机构的动力学分析,发现旋转惯性力矩和往复惯性力矩不平衡,明确了发动机的激励方向和激励频率;通过建立包括动力总成和悬置在内的多体动力学模型,仿真出动力总成六自由度刚体模态,通过优化各悬置的刚度,实现了两种避频方案:方案一是Rx、Rz模态高于1阶激励,低于1.5阶激励;方案二是动力总成6个刚体模态均低于1阶激励。两种方案进行装车试验后,方案二怠速抖动现象得到了明显改善,此优化方案适用于不带平衡轴的三缸发动机悬置系统设计。Idle shake problem occurred during the development of a passenger car with a three cylinder engine without balance shaft,which decrease the NVH performance of the vehicle.In this paper,the dynamic analysis of the piston and crank is done,and it shows the rotating moments and reciprocating moments are unbalanced,so the excitation direction and frequency are determined.By establishing a multi-body dynamic model including the powertrain and mount,the 6-DOF rigid body mode of the powertrain is simulated.By optimizing the stiffness of each mount,two frequency avoidance schemes are realized:Scheme 1 is that the Rx and Rz modes are higher than the first-order excitation and lower than the 1.5-order excitation;Scheme 2 is that the six rigid body modes of the powertrain are lower than the first-order excitation.The idle shake problem of Scheme 2 has been significantly improved after the two schemes are tested.The optimization scheme in this paper is applicable to the design of mounting system of three-cylinder engine without balance shaft.

关 键 词：无平衡轴 怠速抖动 动力总成悬置系统 三缸发动机 

分 类 号：U472[机械工程—车辆工程]