近场水下爆炸对背空圆板冲击作用仿真研究

Simulation Research on Impact Effect of Near Field Underwater Explosion on Open-back Circular Plate

摘要:

在一定的假设条件下,圆板在空气中接触爆炸具有理论解;而在水介质中,近场条件下很难推导理论解。 通过 LS-Dyna 近场条件下全过程模拟计算技术研究水下爆炸载荷对水面圆板冲击作用,得到自由场压力、气泡脉动周期及最大半径、水射流速度等典型特征参数的变化规律,与理论分析结果一致。 揭示了气泡第一周期内脉动形态发展变化过程,获取了结构应力响应、圆板结构变形。 该技术可进一步应用于近场水下爆炸对水面舰船的毁伤评估工作。

Abstract:

Theoretical solutions exist for the contact explosion of circular plates in air under certain assumptions, however, in aqueous medium, it is hard to derive theoretical solutions in near field. This paper studies the impact effect of underwater explo- sion loads on the circular plate at water surface by the LS-Dyna whole process simulation technique under near field conditions, ob- tains the change law of typical parameters such as free field pressure, bubble’s pulsation period and maximum radius, and water jet velocity, which are consistent with the results of theoretical analysis. The changing process of the pulsation form of bubble in the first cycle is revealed, and structural stress response and structural deformation of circular plate are obtained. This method can be further applied to damage assessment of surface ships under near field underwater explosion.