重型自卸车架模态分析和结构优化

Modal analysis and structure optimization for heavy-duty dump truck frame

针对受较大动载荷或作用力的频率与车架某些固有频率接近时,车架会产生强烈的振动,造成破坏或不允许的大变形的问题,采用有限元法对某自卸车冲压铆接车架进行仿真分析.采用刚性单元和梁单元的组合来模拟铆钉连接;用Lanczos方法求解特征值.模态分析结果表明,该车架具有合理的低阶振型和固有频率.利用网格变形技术对车架横梁的位置进行设计优化,使车架的1阶扭转固有频率得到提升.

As to the problem that when the vehicle frame bears larger dynamic load or the force frequencies are close to some natural frequencies of the frame, the frame will produce a strong vibration which could cause damage or non-allowable large deformation, the stamping rivet frame of a dump truck is analyzed and simulated by finite element method. The rivet connections are simulated by combining rigidity elements and beam elements; the eigenvalues are solved by Lanczos method. The modal analysis results show that the frame has reasonable low order vibration shape and natural frequency. The positions of frame cross beams are designed and optimized by using mesh morphing technique, which improves the first order torsion natural frequency.