水下爆炸作用下多舱室结构的动力响应及损伤特性

Research on Dynamic Response and Damage Characteristics of Multi-cabin Structure under the Impact of Underwater Explosion

为探究近水面条件下,水下爆炸载荷强度及爆炸距离等因素对多舱室结构损伤特性的影响,开展多舱室结构的水下爆炸试验,结合S-ALE结构化瞬态流固耦合的数值模拟方法,对近水面爆炸时流场压力载荷的传递分布、结构的动态响应和损伤特性进行分析。基于不同爆炸强度、距离的多工况数值模拟,阐明水下爆炸载荷对多舱室结构的损伤机理,获得爆距变化时冲击波以及气泡载荷冲击做功的比例关系,总结了多舱室结构在爆炸载荷作用下的动态响应特征以及毁伤模式。研究结果表明:多舱室结构会产生剪切破口、撕裂、凹陷塑性变形、压溃屈曲等耦合损伤形式,结构损伤的不连续性和非线性变形引起爆炸气泡的不对称膨胀运动,导致舱室内压力分布呈现冲击波特征和准静态特征;冲击波和气泡载荷共同引起多舱室结构的局部损伤和整体响应,气泡载荷引起的结构动能增长幅度约50%以上。

The underwater blast tests of multi-cabin structures are conducted to investigate the effects of underwater blast load intensity and blast distance on the damage characteristics of multi-cabin structures under near-surface conditions.The numerical simulation method of S-ALE structured fluid-structure coupling is used to analyze the transfer distribution of flow field pressure load,and the dynamic response and damage characteristics of structures during the near-surface blast.The damage mechanism of underwater blast lioad against multi-cabin structures is claritied based on the numerical simulations of different blast intensities and distances,and the proportion of work done by shock wave and bubble load during the change of blast distance is obtained.The dynamic response characteristics and damage modes of multi-cabin structures under blast load are summarized.The result show that the multi-cabin structure produces the coupled damage forms,such as shear breach,tearing,depression plastic deformation,crush buckling,etc.The damage discontinuity and nonlinear deformation of the structure damage cause the asymmetric expansion motion of explosion bubble,resulting in the pressure distribution in the compartment showing shock wave characteristics and quasi-static characteristics;the shock wave and bubble load together cause the local damage and overall response of multi-cabin structure,and the bubble load induces the structural kinetic energy growth of about 50% or more.