面向电磁发射的多场耦合仿真分析方法

Simulation analysis of multi-field coupling field during electromagnetic emission

针对电磁发射中高速运动的电枢与导轨间多物理场耦合计算及时间状态量连续传递问题,采用时间步进耦合算法构建多物理场耦合仿真框架,基于瞬态电磁分析、热传导与有限元方法开发出适用于轨道电磁发射的电磁、热、力多物理场瞬态耦合数值计算程序。并以典型轨道电磁炮为例,建立电磁、热、力三维有限元数值模型,采用单脉冲大电流为激励加载源,动态仿真分析轨道电磁发射中电枢与导轨电流密度、磁感应强度、焦耳热、电磁力等时间状态量的分布。计算结果直观反映出速度趋肤效应等物理现象,同时可方便获取电磁发射中多物理场随空间域和时间域变化的瞬态数据,为电磁发射装置的设计、优化及评估提供仿真计算支撑。

This paper carries out the simulation of the multi-physical coupling field between the armature and the guide rails in high-speed movement during the electromagnetic emission,by using a marching-on-in-time(MOT)coupling algorithm to construct the multi-physical field coupling structure,to study the transient coupling process of the electromagnetic,thermal and mechanical fields by a finite element simulator we have developed based on the electromagnetic analysis and the thermal conduction laws.Taking a typical track electromagnetic gun as an example and with a single pulsed large current as the excitation power,the distributions of the timebased variables such as the current density,the magnetic induction,the Joule heat and the electromagnetic force are simulated dynamically.The calculated results can directly reflect the physical phenomena such as the velocity skin effect,and meanwhile,it is easy to obtain the transient data of the multiple physical fields with spatial and temporal variations during the electromagnetic emission process.The results of this paper can be used for the design,optimization,and evaluation of electromagnetic transmitters.