二级轻气炮内弹道过程数学建模及数值仿真

根据二级轻气炮的发射特点，采用经典内弹道模型描述药室里火药燃烧状况和活塞运动，同时采用一维非定常可压缩流动模型描述轻气室里的气体流动状态和弹丸运动，并通过活塞的运动状态将两者耦合，从而建立起二级轻气炮发射过程的内弹道数学模型；以某30 mm／120 mm轻气炮为基本计算模型，运用四阶Runge-Kutta法求解药室方程，运用二阶MacCormack格式求解轻气室方程，通过两部分的交替计算，实现二级轻气炮内弹道过程的数值仿真，为二级轻气炮的参数设计和发射性能的提高提供了理论依据。

Mathematical Modeling and Numerical Simulation for Interior Ballistics Process of Two-Stage Light-Gas Gun

According to the launch features of two-stage light gas gun,classical interior ballistic model was used to describe combustion of powder in chamber and piston motion,and one dimensional unsteady compressible fluid model was used to describe flowing of gas in light-gas chamber and projectile motion. The two groups of equations were linked through piston motion to develop a mathematical model for interior ballistics launch process of two-stage light-gas gun. A 30 mm/120 mm light-gas gun was taken for the primary computing model. The equations in powder chamber were solved numerically with the fourth-order Runge-Kutta method,and the control equations in light-gas chamber were solved numerically with the second-order MacCormack scheme. The numerical simulation for interior ballistics process of two-stage light-gas gun was accomplished by alternation between these two computations. The simulation results provide theoretical references for parameter design and improvement of launching performance of two-stage light-gas gun.