水面舰船双层结构水下抗爆特性数值模拟

Numerical Simulation on Anti-Shock Performance of Double Structure of Surface Warship Subjected to Underwater Contact Explosion

在充分调研国内外相关文献的基础上,选取当代海战中普遍使用的水下攻击武器以及大型舰船典型双层结构为研究对象,通过非线性有限元程序LS-DYNA,对水面舰船双层结构水下抗爆特性进行数值模拟,分析各层结构在遭受水中兵器接触爆炸时的破坏模式并得出结论:采用所使用的材料模型及网格划分方法所得的结果与经验公式相符,具有良好的工程精度;底部破坏具有明显的网格状,破口受强力构件的限制,沿着强力构件裂开,花瓣状不明显;应力集中区域表现在内外底板间强力构件与内外底板的交接处,特别是龙骨等结构处。在此基础上,从吸能效果的角度计算各层结构的吸能比例,结果显示,在接触爆炸作用下,船底内、外底板间结构是主要的吸能结构,其吸收能量大于内、外底板。

In this paper, some generally used modern naval weapons and the typical double structure of large-sized warships are investigated on the basis of correlative literature review. Particularly, the anti- shock performance of the typical double structure is analyzed with LS-DYNA, and the results show that the model and method of grid divergence applied here agree with the empirical formula in achieving high engineering precision. Also, it has been found out that the damage pattern at the bottom is of visible grid style, and the crevasse appears to split along the strength member in an obscure petal style. Stress-inten- sive regions are mainly joint between the strength member and the bottom especially keels. Subsequent analysis of the energy absorption ratio indicate that the strength member between the inner and outer bot- tom, rather than the bottom itself, is indeed the key energy absorbing structure when contact explosion oc- curs.