同步感应线圈炮内磁场及涡流场的有限元分析

为了研究感应线圈炮内磁场及涡流场的分布,根据单级实心电枢同步感应线圈炮的结构模型,基于矢量磁位和标量电位相结合的方法建立了其导体区域涡流场的数学模型。对套箍和炮管非导体区域、气隙区域分别采用矢量磁位、标量磁位来描述磁场。在电枢区域涡流场的控制方程中,考虑了电枢运动效应和位移电流效应的影响;在驱动线圈区域涡流场的控制方程中,考虑了位移电流效应的影响。采用Ansoft有限元分析软件对单级实心电枢同步感应线圈炮内的涡流场分布情况进行了仿真研究。仿真结果表明:单级实心电枢同步感应线圈炮内的磁场在电枢尾部发生明显畸变,电枢内的涡流主要分布在电枢的外表面和尾部,其方向与驱动电流的方向相反。这些工作体现了单级实心电枢同步感应线圈炮实际工作过程中磁场、涡流场以及能量损耗的分布规律,为感应线圈炮的优化设计提供了参考依据。

Finite Element Analysis of Magnetic Field and Eddy Field in Synchronous Induction Coil-gun

In order to investigate the distribution of magnetic field and the eddy field in the induction coil-gun,a kind of electromagnetic launcher of which the working principle is based on the law of electromagnetic induction,the mathematic model of eddy field in the conductor area of the single-stage solid armature synchronous induction coil-gun is established based on the combination of the magnetic vector potential and the electric scalar potential according to the structure model of the single-stage solid armature synchronous induction coil-gun.The magnetic fields in the non-conductor area(the hoop and the barrel) and in the air area are described by the magnetic vector potential and the magnetic scalar potential respectively.The motion effect of the armature and the effect of the displacement current are considered in the control equation of the eddy field in the armature.The effect of the displacement current is considered in the control equation of the eddy field in the driving-coil.The distribution of eddy field in the single-stage solid armature synchronous induction coil-gun is simulated by the finite element analysis software Ansoft.The simulative results show that the magnetic field near the tail of the armature in the single-stage solid armature synchronous induction coil-gun distorts dramatically and that the eddy in the armature mainly distributes in its outer interface and its tail.In addition,the direction of the eddy in the armature is opposite to the direction of the driving-current.The work embodies the distribution rules of the magnetic field,the eddy field and the energy loss in the working process of the induction coil-gun,and provide reference criteria for the optimum design of the induction coil-gun.