针对电磁轨道发射装置动态发射过程中的多物理场耦合计算问题,采用基于Laplacian方程映射的动网格移动方法,根据多物理场的控制方程,借助有限元仿真平台建立了动态发射条件下电磁场-温度场-结构场的耦合计算模型。根据模型计算,分析了动态发射过程中电枢和导轨上的电流密度、温度和应力等物理量的分布特征。结果表明:该仿真模型能够得到电磁轨道发射过程中的一些典型现象,如电磁扩散和熔化波烧蚀;对于C型电枢结构,电流密度、温升和应力主要集中在喉部区域,如果电枢喉部区域所受的平均应力高于该区域平均温度下的屈服强度,则会造成电枢的变形和断裂。

Aiming at the coupling calculation of multi-physical fields in the dynamic launching process of electromagnetic track launcher, using the moving grid method based on Laplacian equation mapping, and based on the control equations of multi-physics field, with the help of finite element simulation platform, a coupling calculation model of electromagnetic field-temperature field-structure field under dynamic launching conditions is established. According to the model, the distribution characteristics of current density, temperature, stress and other physical quantities on armature and guide rail during dynamic launching are calculated and analyzed. The results show that the simulation model can obtain some typical phenomena during the electromagnetic orbit launch, such as electromagnetic diffusion and melt wave ablation; the current density, temperature rise and stress are mainly concentrated in the throat region for the C-type armature structure. If the average stress in the throat region of the armature is higher than the yield strength at the average temperature in this region, the armature will deform and fracture.