Electromagnetic launcher relies primarily on initial mechanical interference to provide contact pressure on the initial launch phase to maintain good electrical contact performance at the rail/armature (A/R) contact interface. Reasonable design of the bore and armature’s structure can provide good contact pressure and improve the current density distribution at the A/R interface, reducing the melting deposition of the aluminum armature, avoiding the transition phenomenon, and inhibiting the rail grooving. It also has a significant impact on the inductance gradient of the launch system. In this article, we have considered the influence of the caliber width of the electromagnetic launcher on the contact pressure distribution, current density distribution, and acceleration of the payload. It is found that the increase in the caliber width is more favorable for the contact pressure distribution; however, the effect on the current distribution is less. At the same time, as the caliber width increases, the inductance gradient of the electromagnetic launcher system first increases and then decreases. Based on these studies, the optimal caliber width of a rectangular electromagnetic launcher with a caliber height of 20 mm is proposed.

中文翻译：

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口径宽度对电磁发射器发射性能的影响

电磁发射器主要依靠初始机械干涉在初始发射阶段提供接触压力，以在轨道/衔铁（A/R）接触界面处保持良好的电接触性能。合理的内膛和衔铁结构设计可以提供良好的接触压力，改善A/R界面处的电流密度分布，减少铝衔铁的熔化沉积，避免过渡现象，抑制轨道开槽。它还对发射系统的电感梯度有显着影响。在本文中，我们考虑了电磁发射器口径宽度对载荷接触压力分布、电流密度分布和加速度的影响。发现口径宽度的增加对接触压力分布更为有利；但是，对电流分布的影响较小。同时，随着口径宽度的增加，电磁发射系统的电感梯度先增大后减小。基于这些研究，提出了口径为20 mm的矩形电磁发射器的最佳口径宽度。