水下爆炸气泡—波浪非线性耦合运动分析与载荷特性研究

本项目拟针对真实海况下水下爆炸气泡与自由面波浪的非线性耦合开展研究。水下爆炸气泡和波浪载荷均能威胁舰船总强度，舰船受到气泡和波浪联合作用时，两者间的非线性耦合会使问题更为复杂，以往研究较少。对此，本项目在数值方面，拟首先计入气泡内部气体运动的影响，建立MEL-ALE内外域耦合气泡动力学模型，分析气体运动对气泡动态特性的影响规律；在此基础上，结合速度势叠加理论和周期格林函数建立气泡-波浪非线性耦合模型，研究两者耦合运动和载荷特性；最后采用辅助函数分解和模态叠加方法建立水下爆炸气泡-波浪-水面舰船非线性耦合模型，实现两者联合作用下舰船响应特性分析和总强度预报。在实验方面，拟基于气泡动力学、结构动力学和量纲分析方法，推导水下爆炸气泡与舰船相互作用的缩比相似关系，设计并开展相关实验，验证本项目所建立的理论和数值模型。研究成果可为气泡动力学与舰船抗冲击研究提供理论和技术支撑。

This project aims to study nonlinear interaction between underwater explosion bubbles and surface waves and associated loading features on surface warships via numerical and experimental methods. Both the underwater explosion bubble and the surface wave are threats to the total strength of warships, and the coupling effect of the two further complicates the problem. However, relevant researches are scarce. For sake of a better understanding of this problem, in this project an MEL-ALE model is to be established in the first place, describing bubble motion concerning the effect of the bubble’s inner gas. Meanwhile, a model with velocity potential decomposing method and periodic Green’s function is to be proposed to study the nonlinear interaction between the bubble and surface waves. Subsequently, decoupled equations of a Fluid-structure Interaction (FSI) model of bubble, wave and warship is to be adopted to analyze the ship’s total responses. Experiments are also to be conducted for verification of the analytical and numerical models proposed with a similarity relation for the scaled model test deduced via bubble dynamics, structural dynamics and dimension analysis. The outcome of this project will provide support for the research in bubble dynamics and shock resistance of warships in both theoretical and technical aspects.