Study on the impact characteristics of underwater explosion bubble jets induced by plate structure

Abstract

The water jet produced by underwater explosion bubbles during the contraction stage can produce a strong impact on the nearby structure, and its impact characteristics are significantly associated with the explosion distance and azimuth angle. Experiment and ALE method are used to investigate its impact characteristics on the plate structure at different explosion distances and azimuth angles. Through experiments, the coupling process between bubbles and plate structure was recorded, and the accuracy of the numerical method is verified. The results show that when the explosion distance increases, the water jet angle decreases nonlinearly. Due to the inclined water jet, there is an offset distance between the center of the high-stress area induced by the water jet and the geometric center of the plate, and it increases with the increase of explosion distance, while the maximum plate stress decreases gradually. When the azimuth angle α changes from 90° to 0° and then to −90°, the water jet angle θ, the maximum stress and deflection of the plate decrease firstly and then increase. Compared with the negative azimuth angle α, the water jet can produce a stronger impact on the plate when the azimuth angle α is positive.