泡沫覆盖层对水下爆炸气泡射流防护机理缩比试验研究

Reduced-Scale Experiment Study on the Protective Mechanism of Foam Coating Against Underwater Explosion Bubble Jet

水下爆炸会对水中结构物造成严重威胁.柔性覆盖层或夹层板能够降低水中结构物水下爆炸冲击响应,因此成为研究的热点.以往的研究多集中于覆盖层对冲击波的防护机理,适用于较远距离的水下爆炸情况.近距离水下爆炸除了冲击波外,爆炸气泡溃灭时产生的朝向结构物的高速水射流更为致命.该文针对这种情况,基于量纲原理,推导缩比相似关系,通过缩比模型水下爆炸试验发现了覆盖层表面空化微气泡群对爆炸气泡形成高速水射流过程产生干扰,提出了泡沫覆盖层钢板水下爆炸气泡射流防护机理.

Underwater explosion poses a serious threat to underwater structures. Flexible coatings or sandwich plates can reduce the underwater explosion impact responses of underwater structures, and make a research hotspot. Previous studies focused on the protective mechanism of the coating against shock waves, which is suitable for underwater explosion at a long distance. Besides the shock wave, the high-speed water jet towards the structure produced by explosion bubble collapse, is more deadly in the short-distance underwater explosion. In view of this situation, based on the dimensional principle, the reduced-scale similarity relationship was deduced. Through the reduced-scale-model underwater explosion test, it is found that, the cavitation micro-bubble group on the surface of the foam coating interferes with the formation process of the explosion bubble collapse high-speed water jet. The protection mechanism of the foam coating against the underwater explosion bubble collapse water jet for coated steel plates was put forward.