后效期弹丸加速过程的数值模拟  

Numerical Simulation of Bullet Accelerating Process at After-effect Period

作　　者：王兵[1,2] 许厚谦[1] 

机构地区：[1]南京理工大学动力工程学院,南京210094 [2]南京航空航天大学民航学院,南京210016

出　　处：《弹道学报》2008年第4期84-87,共4页Journal of Ballistics

基　　金：国家自然科学基金项目(10476011)

摘　　要：弹丸出膛后,其大位移运动和非恒定的运动速度是膛口流场数值模拟中的难题,为了解决这一难题,运用网格局部重构技术处理弹丸的大位移运动,将对称轴定义为网格变形边界,这使得弹丸在对称轴上的运动过程中不会导致对称轴上的网格体积为负,通过求解轴对称ALE方程组对弹丸出膛后的运动过程进行了数值模拟.由计算结果可以看出整个膛口波系结构的变化过程和弹丸先加速后减速的过程.After flying out of muzzle, the bullet＇s large-scale displacement and its unsteady velocity are the difficult problems in the numerical simulation of muzzle. To solve the problem, local rememshing was applied to deal with the high-speed bullet, and the axis was defined as a special grid-deforming boundary so that the volume of the grids near the axis could not be negative. Arbitrary Lagrangian-Eulerian （ALE） formulation was used to solve the unsteady process of the bullet after it flied out of the muzzle. The result of the simulation indicates that the bullet accelerates first and then slowdown gradually.

关 键 词：膛口流场 弹丸加速过程 局部重构 网格变形边界 轴对称ALE方程组 

分 类 号：O354.5[理学—流体力学]