论文部分内容阅读
建立某无人直升机机身框架的动力学有限元模型,计算得到前六阶固有频率和振型,与模态试验结果相比较,误差小于3%,验证了有限元模型的正确性,表明该有限元模型能准确地反映该无人直升机框架的结构动力学特性。有限元计算的机身框架固有频率值避开了旋翼、尾桨、发动机主通过频率值,满足动力学设计要求。这种有限元计算、试验验证以及模型修改相结合的动力学分析方法,能保证框架固有特性计算的精确,也为无人直升机其它结构的动力学建模提供借鉴。
The dynamic finite element model of an unmanned helicopter fuselage frame was established and the first six natural frequencies and modes were calculated. Compared with the modal test results, the error was less than 3%, which verified the correctness of the finite element model. The finite element model can accurately reflect the structural dynamics of the unmanned helicopter frame. The finite element calculation of the natural frequency of the fuselage frame to avoid the rotor, tail rotor, the main frequency of the engine to meet the dynamic design requirements. The finite element analysis, experimental verification and model modification combined with dynamic analysis method can ensure the accuracy of the inherent characteristics of the frame calculation and provide reference for the dynamic modeling of other structures of unmanned helicopters.