基于炮尾电压的串联增强型电磁轨道炮滑动电接触特性分析

Analysis of Sliding Electric Contact Characteristics of Series-augmented Railgun Based on Breech Voltage

为研究局部增强型电磁轨道炮的滑动电接触特性,提出一种基于炮尾电压的计算分析方法。通过构建接触电阻、炮尾电压、炮尾感应电压以及轨道电流间的数学模型,定量表征电枢与轨道间的滑动接触电阻。根据接触电阻的波形特征,将电枢与轨道间的接触状态分为启动阶段、接触电阻稳步下降阶段、电阻增长阶段和单轨阶段4个阶段。计算了系统的发射效率与接触电阻焦耳热能耗率。结果表明:在电枢启动阶段枢轨间的接触主要为固体-固体接触,接触电阻偏大;逐渐形成的铝熔膜会使实际接触面积增大,改善接触状态;接触电阻与电枢所受到的磁压力呈负相关;接触电阻是影响发射效率的重要因素之一。由此可见对局部增强型电磁轨道炮滑动电接触特性的分析工作为轨道炮的机理研究与设计起到了积极作用。

An analysis method based on the breech voltage is proposed to study the sliding contact resistance characteristics of the partially augmented electromagnetic railgun.A mathematical model of contact resistance,breech voltage,breech inducted voltage and rail current is constructed.The proposed model is used to quantitatively characterize the sliding contact resistance.Through the analysis of the characteristics of the contact resistance waveform,the state of contact between armature and rail is divided into four stages:start-up stage,resistance steady decline stage,resistance growth stage,and single rail stage.The launch efficiency of launching system and the energy consumption rate of contact resistance Joule heat are calculated.The results show that the contact resistance is high as the interface between the armature and rails is in a solid-solid contact state at the initial startup stage;the gradually formed aluminum melt film increases the actual contact area and improves the contact state;the contact pressure is negatively correlated with contact resistance;the contact resistance is an important factor affecting launching efficiency.Therefore,the analysis of the sliding electric contact characteristics of the partially angmented railgun plays a positive role in the mechanism research and design of the railgun.