高速斜入水和水平入水气炮水箱实验系统  

Development of gas guns combined with a water tank for launching high-velocity projectiles into water obliquely and horizontally

作　　者：刘二伟 徐胜利[1] 周杰[1] 左金东 LIU Erwei;XU Shengli;ZHOU Jie;ZUO Jindong(School of Aerospace Engineering,Tsinghua University,Beijing 100084,China;School of Engineering Science,University of Science and Technology of China,Hefei 230026,Anhui,China)

机构地区：[1]清华大学航天航空学院,北京100084 [2]中国科学技术大学工程科学学院,安徽合肥230026

出　　处：《爆炸与冲击》2022年第1期96-106,共11页Explosion and Shock Waves

基　　金：跨水空介质基础科研项目(JCKY2018203B025)。

摘　　要：为开展模型高速斜入水和水中高速航行的水流场实验研究,研制了立式和卧式气炮与水箱组合的实验系统。通过快速阀和活塞阀控制气炮激发和驱动状态,一级气炮采用高压空气直接驱动弹托和模型,二级气炮采用高压空气驱动重活塞压缩使集气腔中产生高压气体,再驱动弹托和模型达到预定速度。通过调节水箱和发射管角度,使高速模型斜入水或水平入水。其中,立式可变发射角二级气炮可发射质量1~1000 g的模型至2500 m/s最大速度,卧式一级气炮可发射质量1~100 kg的模型至300 m/s最大速度。和小气室、高燃气压力火药驱动方式相比,新型气炮采用大体积、中低驱动压力气室,高压气体更接近等熵膨胀做功,调节高压气体压力,能较好地满足模型质量和速度的宽范围要求。结合光反射通断法测速、高速摄影和阴影流场显示等测量技术,得到立式气炮压缩管重活塞运动速度、压缩管末端压力时间曲线和模型倾斜与水平入水的流场阴影图像。结果表明:重活塞速度在膜片破裂前和理论计算值符合较好,但破膜后差异较大。立式气炮流场阴影图像反映了模型斜入水产生的空中和水中激波以及在气水界面的反射激波、空泡形成和侧向气水界面的破碎与飞溅等现象。从卧式气炮的模型水平入水阴影图像提取气泡轮廓,清楚地看出尾部气泡气水界面的波动和失稳。和商业计算软件Fluent计算结果相比,空泡上游区域基本重合,但尾流区域强湍流导致两者存在明显差异。和水洞实验相比,气炮水箱实验系统近真实地再现高速入水过程伴随的冲击和动态空化等物理现象和模型尺度效应。Gas guns with a water tank assembly,were developed for launching projectiles into water obliquely and horizontally.The burst of gas guns was controlled by the quick valve and the piston valve.The cartridges and models in the one-stage gas gun were directly driven by high-pressure air.The heavy piston in the two-stage gas gun was driven by high-pressure air first,and then compressed the air in the gas-gathered chamber to drive the cartridges and models to the predetermined high-speed.By adjusting the angle between the water tank and the launching tube,the high-speed model can entry into water either obliquely or horizontally.The vertical gas gun with variable launch angles,is capable of launching a projectile with mass ranged from several to hundreds of grams at speed ranged from hundreds to thousands of meters per second.The horizontal gas gun can launch the projectile with mass ranged from several to tens kilograms at speed ranged from several to hundreds of meters per second.In contrast to a powder gas gun using small chamber filled with vitiated gas at high pressure and temperature,these gas guns are distinguished for the large volume air reservoir run at medium even low pressure,and characterized by a wide range of mass and speed of the projectile by adjusting the air pressure,which is close to isentropic expansion.Based on light reflection and beam on-off methodology,high-speed photography and shadowgraphy measurements,the results including the piston velocity in compression tube,the pressure time history at the end of the compression tube and the shadowgraph images of water entry and underwater navigation,were obtained.The results show that the piston velocities are in good agreement with the theoretical calculation before the diaphragm bursting,after which the difference increases.The high-speed shadowgraphs in the vertical gas gun clearly indicate the shock waves in the air and water generated by the oblique impacting of the projectile into the water,as well as the reflection of the shock wave on the gas-

关 键 词：一级和二级气炮 流场显示 水中航行 高速入水 

分 类 号：O368[理学—流体力学]