暴雨环境下滑翔制导炮弹气动特性研究

Research on Aerodynamic Characteristics of Gliding GuidedProjectiles in Stormy Conditions

为研究暴雨条件对滑翔制导炮弹气动特性的影响,基于双向动量耦合的欧拉-拉格朗日方法,采用考虑转捩的剪切应力输运湍流模型(Transition SST)和三阶精度的MUSCL格式,建立了暴雨环境下的滑翔制导炮弹气动特性计算模型并进行数值模拟。结果表明:与无雨条件相比,降雨在弹丸表面形成了贴体水膜层,后续雨滴粒子下落时,会冲击弹丸表面水膜形成凹坑,增加了弹丸表面的粗糙度;随着飞行速度的增加,弹体表明温度逐渐升高,水膜层的厚度随着蒸发不断减小;当炮弹以亚跨音速飞行时,暴雨环境对炮弹气动系数有较大的影响,当炮弹以Ma=0.8的速度在降雨强度为2 200 mm/h的工况下飞行时,阻力系数提高了27.39%,升力系数减小了18.09%。同时,随着降雨强度的提高,炮弹阻力会呈现先增加后减小再增加的趋势,但此差异会随着炮弹飞行速度的增大而逐步消失,而升力系数会不断下降;在降雨强度不变,炮弹飞行速度达到Ma=0.95时,阻力系数提高了32.29%,升力系数减小了18.38%;当炮弹飞行速度达到Ma=1.2时阻力系数提高了21.76%,升力系数减小了18.87%。

To study the effect of heavy rainfall on the aerodynamic characteristics of gliding-guided projectiles,a model based on the Euler-Lagrange method with two-way momentum coupling,the Transition SST(shear stress transport turbulence model)and the MUSCL format with third-order accuracy were developed to calculate the aerodynamic properties of the projectiles under heavy rainfall.The results reveal that heavy rainfall creates an advective water film layer on the projectile surface,but the subsequent impact of raindrop particles on the surface results in craters forming and increasing surface roughness.The study shows that the rainstorm environment significantly impacts the lift and drag coefficients of the projectile,with a 27.39%increase in drag coefficient and an 18.09%decrease in lift coefficient observed when Ma=0.8 under a rainfall intensity of 2200 mm/h.Additionally,the study shows that with an increase in rainfall intensity,the drag of the shell exhibits an initial increase,followed by a decrease,and then an increase again.However,this trend disappears as the projectile’s flight speed increases while the lift coefficient decreases.These findings can aid in optimizing the performance of gliding-guided projectiles in adverse weather conditions.When the rain intensity remains unchanged and the projectile velocity reaches Ma=0.95,the drag coefficient increases by 32.29%and the lift coefficient decreases by 18.38%.When the projectile velocity reaches Ma=1.2,the drag coefficient increases by 21.76%and the lift coefficient decreases by 18.87%.