多匝串联并列轨道炮U形电枢接触界面熔蚀规律分析

Analysis of Melting Erosion Characteristic on the Contact Interface between U-shaped Armature and Rails for Multiturn Serial-parallel Railgun

针对一种多匝串联并列轨道炮U形电枢与轨道接触界面的熔蚀问题,通过电磁-结构-热多物理场耦合分析,对不同电流峰值、不同过盈量的膛内电枢速度、界面接触压力、界面温度等进行了数值仿真,并开展了相关验证试验,得到了接触界面熔蚀规律。仿真和试验结果表明:发射过程中电枢与轨道间的接触压力随电流波动而变化;接触压力越大,摩擦热功率越大,而接触电阻的焦耳热功率越小;合理设计电枢过盈量参数,可进一步改善滑动接触界面的环境温度;由于滑动过程中不可避免的磨损,电枢接触面熔蚀区域从初始接触区域逐渐向尾部转移,试验结果验证了仿真方法的有效性。

An electromagnetic-structure-themlal muhi-physics coupling model is established to study the mehing erosion on the contact interface between U-shaped armature and rails of a muhitunl serial-parallel railgun, and the armature velocity, contact pressure and temperature of interface in the case of dift^rent current peaks and shrink ranges are analyzed. The related verification experiments were made to obtain the mehing erosion characteristic of contact interface. The simulated and experimental results show that the contact pressure between armature and rails varies with current fluctuation during launching. The friction heat power varies directly with the contact pressure, but Joule thermal power caused by contact resistance varies inversely with the contact pressure. The ambient temperature of the sliding contact inter- face can be further improved by reasonable design of armature shrink range. Due to the inevitable wear during sliding, the melting area of armature contact surface gradually transfers from the initial contac tarea to the tail of ala^lature. The experimental results validate the effectiveness of the simulation method.