轨道炮电枢电动力转捩形成机理与仿真分析

Formation Mechanism and Simulation Analysis of Railgun Armature Electromagnetic Transition

轨道炮电枢转捩引起轨道烧蚀和发射参数变化,是制约轨道炮性能提升的关键问题之一。分析了电流下降段轨道炮电枢电动力转捩形成机理,给出了电枢转捩判断模型和电磁场参数计算模型,采用有限元软件ANSYS Workbench对电枢转捩形成过程进行了仿真分析,仿真了该过程中的电流、电磁力分布以及电磁力引起的电枢形变情况,分析了电流下降率对电枢转捩的影响。仿真分析结果表明:电流下降段电枢内部会感应出涡流,涡流可能引起电枢尾部区域电磁力改变方向,甚至电枢尾部形变,进而导致电枢转捩发生;电流下降率越大则电枢受到的反向电磁力越大,电枢转捩越容易发生。

Armature transition of railgun causes rails erosion and change of launching parameters, which is one of the key problems restricting the performance of railgun. The formation mechanism of armature transition at the down-slope of driving current is analyzed. The armature transition estimation model and electromagnetic parameters calculation model are given. The formation process of a：rmature transition at the down-slope of driving current is simulated by AYNSYS Workbench. The current and magnetic field distribution are simulated, so as the armature deformation caused by the armature electromagnetic force. The effect of current dropping rate on armature transition is analyzed. The simulation and analysis result show that, the eddy current at current down-slope may lead to change the direction of electromagnetic force in armature tail, even the deformation of armature tail, which leads to the armature transition. The reverse electromagnetic force in armature tail increases with the increasing of the driving current dropping rate. As a result, the armature transition occurs more easily.