横向脉冲磁场下悬臂导电薄板的动力屈曲

Dynamic buckling for cantilever conductive thin plates under transverse impulsive magnetic field

针对处于外加横向强脉冲磁场下的悬臂导电薄板,建立了计及面内电磁体力、磁场、涡电流场和变形场的理论模型.对空间部分采用有限元法,对涡电流、导电薄板的时间部分分别采用 Crank Nicolson法和 Newmark法,给出了计算程序的求解步骤,定量模拟了强脉冲磁场对面内磁体力和薄板最大挠度的影响.仿真结果表明,由涡电流与磁场相互作用所产生的面内磁体压力直接导致了悬臂导电薄板发生动力屈曲,导电薄板发生屈曲时临界磁场值随着脉冲参数的减小而减小,但随着电导率的增大而减小.

A theoretical model for cantilever conductive thin plates under externally lateral strong impulsive magnetic field was established with in-plane magnetic volume forces, magnetic field, eddy current field and deformation field included. The numerical steps of algorithm routine were given by adopting the finite element method for the spatial part, and the Crank-Nicolson and the Newmark methods in eddy current and conductive thin plate respectively for the time part. The influences of strong impulsive magnetic field on the in-plane magnetic volume forces and the maximum deformation of thin plate were quantitatively simulated. The simulation results indicate that the dynamic buckling phenomenon is directly caused by the in-plane magnetic volume compression forces arising from the interaction between the eddy current and the magnetic fields. The critical magnetic field value reduces with the decreasing impulse parameter and the increasing conductivity when the conductive thin plate buckles.