一级气体炮制退器的流场仿真与性能研究

Flow Field Simulation and Performance Study on First Stage Gas Gun Brake

为了最大程度消减一级气体炮发射中的后坐效应,研究了一级气体炮制退器的流场特性和制退效率。基于三维非定常Navier-Stokes方程构建了发射炮管制退器的数值仿真模型,采用动网格技术,对比分析了有/无炮口制退器的流场,揭示了高速弹体飞离制退器时气流冲击波的形成、发展和衰减的整个动态演变过程,探究了孔径对制退器流场形态的影响。分析表明:炮口制退器对最大后坐力降低了14.7%;制退器孔径直接改变了进入中央弹孔通道和侧孔通道的气流量分配比,影响了制退效率;当制退器的气流孔径增大为22 mm时,在发射压力25 MPa下制退效率达到23.38%。对炮口制退器的流场形态和制退效率的影响规律进行了分析,可为高压动态气体发射制退提供基础依据。

In order to reduce the recoil effect of first stage gas gun,flow field characteristics and recoil efficiency of the first stage gas gun brake were studied.The numerical simulation model of muzzle bar-rel was established based on the 3D unsteady Navier-Stokes equation.The flow field with/without muz-zle brake was analyzed by using the dynamic mesh technology.The whole dynamic evolution process of the formation,development and attenuation of air flow shock wave was revealed when the high-speed projectile flew away from the brake,and the influence of the aperture on the flow field morphology of the brake was reaearched.The analysis shows that the muzzle brake reduce maximum recoil force by 14.7%.The diameter of the brake directly changes the air flow distribution ratio into the centra and side hole channel and affects the braking efficiency.When the air flow aperture of the brake is in-creased to 22 mm,the brake efficiency reaches 23.38%under the launching pressure of 25 MPa.The study on the flow field shape and the influence law of brake efficiency provides a reference for high-pressure dynamic gas launch brake.