二级轻气炮内弹道的数值模拟与性能分析

NUMERICAL SIMULATION AND PERFORMANCE ANALYSIS OF THE TWO-STAGE LIGHT GAS GUN

为了优化二级轻气炮的设计参数和工作参数,必须进行数值模拟。本文介绍了准一维不定常流的Lagrangian算法,讨论了数值模拟中的若干问题,分析了气动过程。根据我们的数值模拟,归纳了影响气炮性能的一些基本规律,可供选择工作参数时综合分析。

In order to optimize the performance of the two-stage gas gun, the initial--boundary value problems for quasi-one-dimensional unsteady flow are solved by difference method. The influence of operating parameters on the performance is as follows: (1) The opening pressure for rupture valve between breech and pump tube influences the use degree of the gun powder. (2) The increase of the opening pressure for rupture valve between the pump tube and barrel leads to a small increase in calculation projectile velocity and essentially increase in the stresses in the pump tube.(3) In view of large inertia, heavy piston can not undergo slowing down guickly. resulting in higher stresses in the tapered section (4) The projectile velocity does not increase monotonically with piston velocity in certain range of the piston velocity. (5) At the appropriate initial filled pressure. the maximum projectile velocity is not correspondence to maximum stress in the tapered section.