Abstract：Based on Fluent fluid simulation software, and used the finite-volume method, VOF multiphase flow model and overlapping grid technique, a numerical method for parallel entry of supercavitating projectiles into water is established to study the water entry performance of supercavitating projectiles in asynchronous parallel. The high-speed water entry experiment of single projectile is carried out by using high-speed camera and light gas gun. The reliability of the numerical method is verified by comparing the simulation results with the experimental results. On the basis of this numerical method, the water entering process of parallel supercavitating projectiles with initial longitudinal spacing of 0，0.5，1，1.5，2 and 3 times of projectile length is numerically simulated, and the flow field characteristics and motion characteristics of two projectiles with different longitudinal spacing are compared and analyzed. The results show that the coupling relationship between the cavities of the asynchronous parallel projectile is different from that of the synchronous parallel projectile; When the initial longitudinal distance is 0.5 times of the length of the projectile, the cavity of projectile 1 is squeezed violently by the cavity of projectile 2, and the right side of projectile 1 pierces the cavity and a tail beat occurs; When the initial longitudinal distance is three times the length of projectile, the cavitation interference of projectile 2 by projectile 1 is obvious, and the projectile is completely unstable in the later stage of water entering; Compared with synchronous parallel, the impact load of projectile 2 in asynchronous parallel is smaller. And as the initial longitudinal spacing increases from 0 to 3 times the projectile length, the impact load of projectile 2 shows a decreasing trend.
Key words: asynchronous parallel water-entry；cavitation evolution；motion characteristics；numerical simulation；water-entry experimental
闫雪璞，鹿麟，王辰，李强，胡彦晓. 超空泡射弹异步并联入水流场与运动特性研究[J]. 振动与冲击, 2022, 41(16): 167-176.
YAN Xuepu,LU Lin,WANG Chen,LI Qiang,HU Yanxiao. A study on flow field characteristics and motion characteristics of two supercavitating projectiles in asynchronous parallel water-entry. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(16): 167-176.
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