药柱燃速对底排工作过程及底排弹射程影响的数值模拟

为了研究底排药柱燃速对底部排气弹底排装置工作过程和射程的影响,采用计算空气动力学和质点外弹道学耦合的方法求解底部排气弹的飞行弹道,研究了底部排气弹在整个减阻阶段底排装置工作参数、工作状态、底排流场等随时间的变化,分析了药柱燃速对底部排气弹工作过程和射程影响。结果表明:数值模拟结果与制式底部排气弹靶场试验结果吻合,说明建立的计算模型合理;燃速调整系数由0.8提高到1.2时,燃烧时间由36.8 s减少到18.4 s,射程由38.12 km下降到36.21 km,增程率由33.32%下降到26.64%;不同底排药柱燃速的底部排气弹在减阻阶段的排气参数均随时间的增加而呈先增大后减小的趋势;采用高燃速底排药柱的底部排气弹排气质量流率相对于低燃速的底部排气弹较大,但减阻效果并没有明显提高。

Numerical Investigation on the Effect of Combustion Rate of Propellant on the Operation Process and Firing Range of the Base Bleed Projectile

In order to research the effect of combustion rate of the propellant on the operation process and the firing range of base bleed projectile, the flight ballistic of base bleed projectile was solved by using the computational aerodynamics coupled with particle trajectory. The changes of operation parameter, operation status, flow filed of base bleed projectile with time in the drag reduction stage were studied. The effect of combustion rate of propellant on the operation process and firing range of base bleed projectile were analyzed in detail. The simulation results are in good agreement with the target range test results of the standard base bleed projectile, indicating that the calculation model established is correct and reasonable. When the combustion rate adjustment coefficient changes from 0.8 to 1.2, the combustion time decreases from 36.4 s to 18.4 s, firing range decreases from 38.12 km to 36.21 km and the extended-range rate decreases from 33.32% to 26.64%. With the increasing of time, the base bleed parameters of the base bleed projectile with different combustion rate increase first and then decrease during the drag reduction period. The bleed mass flow rate of base bleed projectile with high combustion rate is larger than that of the base bleed projectile with low combustion rate, but there is no obvious increase of reduction drag effect.