接触电阻对电磁轨道炮电磁场影响分析

Effect Analysis of Contact Resistance on Electromagnetic Field of Electromagnetic Railgun

为考察接触电阻对电磁发射性能的影响,对矩形截面的铜导轨和C形铝电枢组成的发射装置进行三维有限元模拟。根据电枢与导轨间接触压力计算枢轨表面接触电阻,分别对考虑接触电阻下和理想接触下的电磁轨道发射装置进行电磁场计算,分析接触电阻对于电磁发射装置的影响。计算结果表明:接触电阻急剧增加又急剧减小到最小值后,随着电流的减小又逐渐增加;接触电阻对于发射方向洛伦兹力没有影响,接触电阻改变了枢轨接触表面的电流密度的最大值和分布,但对于电枢喉部电流密度的最大值和分布没有影响。

In order to investigate the influence of contact resistance on electromagnetic field, the 3 D finite element simulation is applied to analyze the electromagnetic launcher composed of copper rail and the C type aluminum armature. First, the contact resistance is calculated according to the contact pressure between the armature and the rail. Then, the electromagnetic field of electromagnetic launcher under contact resistance and ideal contact is calculated by Maxwell, respectively. Finally, the influe-nce of contact resistance on electromagnetic launcher is analyzed by comparing the numerical data. The calculation results show that the contact resistance increases sharply and then decreases sharply to the minimum, the contact resistance has no effect on the Lorentz force in the direction of launching, while it has an influence on the Lorenz force in the direction of vertical and guide, and the contact resistance changes the maximum current density of the contact surface of the rail. And distribution, but have no effect on the maximum and distribution of current density of armature throat.