一种新型埋头弹闭气结构设计及仿真分析

Design and Simulation Analysis of a New Gas Seal Structure for Cased Telescoped Ammunition

为解决现有埋头弹不能兼顾规整外形和自带闭气结构的问题,在埋头弹炮筒前端增加了锥角为24°的倒角结构,在自动机旋转药室端面增加了闭气沟槽。炮弹发射过程中,火药燃气压力使炮筒前端倒角贴紧身管壁,实现闭气;炮弹前端外形出现缺陷时,旋转药室上的闭气沟槽能有效减缓火药燃气外泄。对设计的埋头弹进行了有限元分析和流体动力学仿真分析,结果表明,设计的埋头弹,炮弹外形规整,结构简单,与自动机匹配良好,能有效实现闭气;当炮弹外形受到不可抗力损坏时,依靠火炮辅助闭气结构,能对发射全过程的火药燃气外泄进行有效减缓。

Current cased telescoped ammunition(CTA)is struggling to strike a balance between its regular shape and integral gas seal structure.In order to solve this problem,a chamfer with a 24°taper is added at the front end of the CTA case while an gas sealing groove is added at the end face of the swinging chamber of the cannon.During firing,the front end of the case is pressed against the barrel wall by the pressure of the burning gas,realizing gas sealing.When the front end of the shell is damaged,the gas sealing groove on the swinging chamber can effectively slow down the leakage of the burning gas.The model is analyzed by finite element analysis and hydrodynamic simulation,the results show that the CTA designed features a regular shape,simple structure and can be in good alignment with the swing-chamber mechanism and effectively seal gas.Even if the ammunition is damaged,the auxiliary gas sealing structure in the cannon can still effectively slow down gas leakage in the whole firing process.