基于CFD的转管机枪助旋制退器流场超压仿真及对弹丸初速影响分析

为了研究转管机枪助旋制退装置流场超压特性及对弹丸速度的影响,运用经典内弹道方程求解流场边界条件,采用计算流体力学中的非粘性、非定常可压缩气体流动方程和动网格技术,对有、无膛口旋转制退装置的膛口流场进行了数值仿真,对弹丸的增速规律进行了计算。对2种情况的仿真结果进行了分析对比,结果表明:有助旋制退装置时膛口流场最大超压值增加约2倍,弹丸速度增加3.61 m/s。

Simulation of Flow-field Overpressure of Torque Assist and Brake for Rotating-barrel Machine-gun Based on CFD and Analysis of Its Effect on Projectile Muzzle Velocity

To study the flow-field overpressure of torque assist and brake of rotating-barrel machine-gun ( RBMG) and its effect on projectile velocity,the classical interior ballistic equations were used to solve the flow field boundary conditions,and the unsteady compressible non-viscous gas-flow-equations and dynamic mesh technology of computational fluid dynamics( CFD) were applied,and the flow field of muzzle was nu-merically simulated. Simulation results of flow fields with and without muzzle torque assist device were discussed,and the projectile velocity was computed. The result shows that the maximum overpressure value of flow field of muzzle with torque assist and brake increases by about 2 times,and the maximum velocity of projectile increases by 3. 61 m/s.