摘要
针对某车型全加速工况下引起的车内噪声及底板振动问题,应用LMS公司的Test.Lab动态测试系统对发动机动力总成进行振动、噪声和不平顺性测试,通过频谱分析和模态实验响应分析找到引发车内噪声和振动的相关故障频率;通过Hyperworks软件对发动机后悬置支架进行仿真计算,对比试验结果和仿真结果,发现其低阶固有频率过低,与发动机的工作状态频率发生共振,使车内声品质变差,主观感觉底板有明显抖动.为此提出改进发动机后悬置支架结构来改变支架固有频率的方案,使其与发动机工作频率错开.进一步试验发现,车内噪声和底板抖动问题得到明显改善.
Aiming at the vehicle interior noise and the floor shaking problem arising under the whole open throttle condition, vibration, noise and irregularities of the engine power assembly are tested by using the Test.Lab dynamic testing system of LMS Company. Based on the frequency spectrum analysis and modal experiment response analysis, the related failure frequency of the problem is found. The modal analysis on the engine rear suspension bracket of the automobile was simulated by Hyperworks software. Comparing the simulation results with the testing results, it is found that the resonance will occur between the rear suspension bracket and the engine, because the inherent frequency of lower order of the bracket is too low to approximate to the engine＇s working frequency. So the floor would subjectively shake obviously, and the sound quality in the automobile would be poor. Hence, an improving scheme on the design of the structure of the engine rear mount bracket is proposed to avoid the coincidence of the natural frequency for the bracket with the engine＇s working frequency. Further testing proves that the arising problem has been improved significantly.
出处
《广西科技大学学报》
2017年第1期65-72,共8页
Journal of Guangxi University of Science and Technology
基金
国家自然科学基金项目(11502056)
广西自然科学基金项目(2015GXNSFBA139007)
广西重点实验室开放基金项目(1404544)
广西工学院博士基金项目(12Z09)资助
关键词
发动机
后悬置支架
固有频率
模态实验
仿真分析
engine
rear suspension bracket
natural frequency
modal testing
simulation
