中文摘要：

为了研究火炮水下气幕式发射过程中喷射结构对气幕特性的影响，建立了多股燃气射流在充液圆管中扩展的三维非稳态数理模型，获得了多股燃气射流在充液圆管内气液两相组分、压力与速度分布规律。计算结果表明：多股燃气射流从喷孔喷出后。在液体中形成多个Taylor空腔，通过Taylor空腔与液体湍流掺混生成管内气幕。由于气液湍流掺混作用导致流场内压力出现波动，汇聚界面产生低速涡流区域。斜面喷孔直径由1．5mm增大至2mm，斜面射流回流作用增强，导致由斜面射流与侧壁射流汇聚而成的侧面射流轴向扩张能力提升，气幕整体排水性能增强，8ms时气幕上方液体运动速度由8．26m·s-1增大至9．4m·s-1。

英文摘要：

To research the influence of injection structure on gas-curtain generated by underwater launched gun, the three-dimen- sional unsteady mathematical model of multi gas jets in liquid tube was established, and the distribution of phase, pressure and ve- locity were numerical acquired. Numerical result indicates that after the injection of multi gas jets, Taylor cavities are formed in the liquid Tube. With the mixing process between the Taylor cavities and liquid medium, the multi gas jets merges and the gas- curtain is generated. During the merging process, the pressure in the flow field fluctuates and low-velocity vortex areas are formed on the gas-liquid interface. When the diameter of the slant nozzles increases from 1.5 mm to 2 mm, the reflux of the oblique jets is enhanced, which can result in the improvement of axial expansion performance of the side jets, and the drainage performance of gas-curtain is strengthened, the velocity of the liquid above the gas-curtain increases from 8.26 m ·s-1 to 9.4 m· s-1 at 8 ms.