准静态法及瞬态法在扭力梁耐久开发中的研究

The Research of Quasi-Static Method and Transient Method in the Development of Torsion Beam Durability

目前车身及底盘件的疲劳分析,通常采用准静态法获取动应力,再进行损伤计算。本文结合某款EP车路试后扭力梁开裂问题,同时结合后扭力梁自身特点,对比介绍准静态法及模态瞬态法及直接瞬态法三种获取动应力的方法,分析三种方法损伤结果风险区域与实际路试开裂区域关联程度,以探讨最适用于后扭力耐久分析的方法。得出针对后扭力梁的疲劳损伤分析,考虑频率影响的瞬态法损伤分析结果与实际路试结果更为吻合,同时兼顾效率的模态瞬态法更适用于后扭力的耐久开发。

At present, the quasi-static method is usually used to obtain the dynamic stress for fatigue analysis of body and chassis parts,and then the damage is calculated. In this paper, three methods of obtaining dynamic stress, namely quasi-static method, modal transient method and direct transient method, are introduced by comparing the cracking problem of a certain EP torsion beam after road test and the characteristics of the post-torsion beam. And the correlation degree between the risk area of damage results and the actual road test cracking area was analyzed by the three methods, so as to explore the most suitable for the rear torsion beam durability analysis method. At the same time, the method suitable for analyzing the fatigue damage of post torsion beam is discussed. The results of fatigue damage analysis with transient method considering the influence of frequency are more consistent with the results of actual road test.The modal transient method considering the efficiency is more suitable for the durable development of the rear torsion beam.