扭振对轴承受力及整机噪声影响的研究

针对曲轴扭转振动与整机辐射噪声问题,以某直列四缸发动机曲轴系统为研究对象,基于AVL Excite软件,在匹配扭振减振器(torsional vibration damper,TVD)与不匹配TVD两种情况下,采用弹性流体动力学模型轴承计算模型研究了曲轴扭振对机体所受激励与轴瓦表面压力分布的影响;并且在两种情况下,分别对曲轴扭振与车内噪声进行了试验测试,测试与主观评价表明,匹配TVD情况下曲轴扭振幅值降低,车内原有异响声明显改善。研究分析结果表明,扭振会使得曲轴模态频率附近范围内机体所受激励幅值增加,改变轴瓦表面载荷的幅值与分布规律,导致发动机乃至整车产生异响。

Influence of the crankshaft torsional vibration to force of bearings and noise radiation of the engine

Aiming at the influence of crankshaft torsional vibration to engine noise,taking the crankshaft system of an inline four-cylinder engine as the research object,based on elasto-hydro dynamic model,the impact of torsional vibration to total force and pressure distribution of main bearings was researched respectively in cases of with torsional vibration damper(TVD) and without TVD.Measurements of torsional vibration of the crankshaft and noise inside the vehicle were also carried out under the two cases.Testing and subjective evaluate show that at the condition of with TVD,torsional vibration amplitude decreased,the original abnormal sound of the vehicle was improved significantly.The results indicate that crankshaft torsional vibration can increase the amplitude of the excitation on engine block and change the distribution of the load on the bearing surfaces,which can result in abnormal sound of the engine and vehicle.