电磁轨道发射器临界速度仿真研究

Simulation Study on Critical Velocity of Electromagnetic Rail Launcher

针对电磁轨道发射器动力学响应研究存在的问题,推导得到研究电磁轨道发射器动力学响应问题的解析解,建立以Bernoulli-Euler(B-E)梁、三维矩形截面轨道为研究对象的有限元模型;从临界速度解析解、动力学响应解析解、有限元梁模型等方面,对三维有限元模型进行验证;通过对有限元软件的二次开发,实现了轨道电磁排斥力和枢轨接触力幅值随时间、随发射距离的瞬态加载。研究表明:电磁轨道发射器二维梁模型的数值解和推导得到的解析解具有较好一致性;提出三维有限元计算模型对临界速度的计算误差不超过1.2%;解析模型和三维有限元计算模型对动力学响应计算结果振动周期具有较好一致性,轨道变形幅值具有一定差异,在电枢作用区域轨道变形幅值差异最大;动态发射过程轨道变形幅值与电流正相关,临界速度会导致轨道变形明显增大。

Aiming at the problems existing in the study of the dynamic response of electromagnetic rail launcher,this paper derived the analytical solution for studying the dynamic response of electromagnetic rail launcher and established the finite element models based on simplified electromagnetic rail launcher.In addition,the dynamic response model under sequential discharge conditions was established and this model was verified through the analytical solution of critical velocity,analytical solution of dynamic response and finite element beam model.The results show that the numerical solution of the two-dimensional beam model is in good agreement with the analytical solution.The calculation error of the critical velocity calculated by the three-dimensional finite element calculation model does not exceed 1.2%.The analytical model and the three-dimensional finite element calculation model have a good consistency in the vibration period,and the rail deformation amplitude has a certain difference and the difference of rail deformation amplitude is the largest in the armature action area.The rail deformation amplitude is positively correlated with the current,and the critical velocity causes the rail deformation to increase significantly.