Numerical simulation of launching process of air gun impact test-bed
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摘要: 利用计算流体动力学方法对单级空气炮碰撞实验台的发射过程进行了数值仿真,所得碰撞车发射速度与实验结果吻合。在此基础上,对碰撞车发射过程的流场变化、车体前后压力以及储气罐压力变化进行分析。结果表明,泄漏气体先于碰撞车充满整个发射空间,形成初始流场,使得车前压力出现正负交替现象,但其数值较小,对车体加速过程的影响可以忽略。当碰撞车进入泄压段后,受冲击射流作用,碰撞车仍处于加速状态,且速度增量约为2 m/s。Abstract: We simulated the launching progress of SSAGIT using the computational fluid dynamics (CFD) and the velocity of the impact car obtained from calculation are consistent with the experiment results. Based on this, we investigated the flow field, the pressure in the front and back of the car, and the pressure of the gasholder. The results showed that the launch field was filled with the leakage gas before the arrival of the impact car, causing the development of an initial flow field, and the alternatively positive and negative variations of the pressure in the front of the car, but its influence on the acceleration process was negligible because of its small value. In addition, the acceleration was maintained due to the effect of the jet after the impacted car entered the decompression part, and the increment was about 2 m/s.
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Key words:
- computational fluid dynamics (CFD) /
- simulation analysis /
- dynamic mesh /
- air gun
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表 1 工况参数
Table 1. Parameters in two different work conditions
工况编号 m/kg p0/MPa T/℃ C1 355 0.98 20 C2 1 040 2.98 13 表 2 实验速度
Table 2. Experiment velocity
实验编号 C1 C2 v1/(m·s-1) v2/(m·s-1) v1/(m·s-1) v2/(m·s-1) 1 78.1 79.8 80.3 82.1 2 77.6 79.5 80.0 81.7 -
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