一种基于动态嵌套网格的膛内弹托分离力预测方法

A Prediction Method of Sabot Separating Force in Barrel Based on Moving Chimera Grid

通过给定运动参数,采用动态嵌套网格和等位移变时间步长技术求解二维轴对称非定常N-S方程,精确模拟从发射到脱离炮口影响区的全过程。通过对某高速弹药发射过程模拟,获得了详细的瞬时非定常流场和分离力变化曲线,分析了分离力的变化规律并找出了分离力随时间/位移曲线出现二次峰值的原因;最后,对工程设计中弹托分离力阈值的确定给出了建议。

In this paper,by specifying motion parameters,a numerical method is developed to simulate entire sabot motion process from launch to exit muzzle blast,which solves 2D axial symmetry unsteady N-S equations with equal displacement variable time step size and moving chimera grid technology.The numerical launch process of a high velocity projectile is accomplished,and the detailed instantaneous unsteady flow and sabot separating force variation curve are obtained.The change rule of sabot separating force is analyzed,and the reason for the second peak value in separating force vs.time or displacement variation curve is confirmed.Finally,there are some proposals on the threshold of sabot separating force in engineering design.