FSAE赛车车架系统的模态分析及动态性能评价

Modal analysis and dynamic performance evaluation of the system of FSAE racing car frame

针对FSAE赛车在行驶过程中车架受到的来自路面不平度、车轮动态不平衡和电机振动的激励从而导致的共振破坏的问题,以及为了合理安排负载在车架上的安装位置,通过采用ANSYS中的Block Lanczos法对车架系统进行了自由模态分析和约束模态分析(约束模态分析的对象包括"悬架-车架"系统、"车架-负载"系统和"悬架-车架-负载"系统)。通过对比分析车架的自由模态分析振型特点与3种车架系统的约束模态分析振型特点,得出了"悬架-车架-负载"系统的振型来源于车架子系统(车架,"悬架-车架"系统和"车架-负载"系统)的振型,提出了"悬架-车架-负载"系统的改进方案以提高整车动态性能。通过"悬架-车架-负载"系统的柔性约束模态试验,验证了仿真数据的正确性。研究结果表明,该车架能满足赛车手舒适性要求,能避免共振破坏的发生。

Aiming at solving the problem of the frame resonance which was stimulated by the excitation generated from uneven road surface,the rotationally wheels and vibration of electric machinery when FSAE car was driven on the road,and to reasonably arrange the installation position of the load on the frame,free modal analysis and constrained modal analysis were investigated respectively（ the objects of the modal analysis included the suspension-frame system,the frame-load system and the suspension-frame-load system）. The vibration mode characteristics of the free modal analysis and the vibration mode characteristics of three frame systems were compared and analysed. It was indicated that the vibration mode of the suspension-frame-load system derives from the vibration mode of the frame subsystem（ the suspension-frame system and the frame-load system）. The improved scheme of the suspension-frame-load system was presented for improving the dynamic performance of the frame system. The flexible restraint modal test of the suspension-frame-load frame system was carried out,and the correctness of the simulation data was verified. The results indicate that the frame system can meet the comfort requirements,can avoid the occurrence of resonance.