离心机和密闭加压容器中水下爆炸相似关系

水下爆炸冲击波和气泡脉动的共同作用不能仅依据几何相似条件进行模型试验,相关的尺寸缩比模型试验可以借助密闭加压罐或离心机进行。通过量纲分析和π定理对模型试验的相似理论进行了推导,分别探讨了密闭加压容器和离心机中水下爆炸的相似关系及其适用范围,并对原型工况和尺寸缩比为1/20和1/30的模型工况基于LS-DYNA进行了数值模拟。结果表明:加压模型试验中水下爆炸冲击波、气泡脉动半径和周期可以满足相似关系,但是气泡迁移和射流不符合相似关系;离心模型试验中水下爆炸冲击波和气泡脉动基本完全相似。

Similarity relations of underwater explosion in centrifuge and pressurizing vessels

The collective effect of underwater explosion shock wave and bubble pulsation does not meet the traditional geometric similarity relation, and the scaled model test must be carried out in a closed pressurized tank or centrifuge apparatus. Through the dimensional analysis and π theorem, the similarity theory of the model tests was deduced. The prototype condition and model conditions with the scaled ratio of 1/20 and 1/30 were simulated based on LS-DYNA, which shows the similarity relations and application scope of the pressurized model and centrifugal model. The shock wave, bubble radius and bubble period can meet the similarity relations but the bubble motion and jet can not meet the similarity relations in the pressurized model; and the shock wave and bubble pulsation almost meet the similarity relations in the centrifugal model.