基于ALE算法的V形楔形体入水的水动力特性分析

HYDRODYNAMIC BEHAVIOR ANALYSIS OF WATER ENTRY OF V-SHAPED WEDGE BASED ON ALE METHOD

结构入水问题是一种复杂的流固耦合过程,涉及到固体力学、流体力学、冲击动力学和计算力学等相关力学分支的交叉与融合.论文基于非线性显式动力分析方法,采用任意拉格朗日-欧拉算法(水域采用欧拉描述,固体结构采用拉格朗日描述),并用罚函数方法控制结构与流体之间的耦合作用,对二维V形楔形体垂直入水的初期过程进行了数值仿真.通过数值仿真,分析了楔形体底部压力分布情况,讨论了网格密度、接触刚度以及阻尼系数对数值计算结果的影响,并将数值结果与Wagner理论解进行了对比分析,验证了ALE方法的可靠性.

Water entry of structures is a complicated problem of fluid-structure coupling,which involves the crossing and blending of related mechanical branch,such as solid mechanics,fluid mechanics,impact dynamics and computational mechanics etc.The present paper,based on the nonlinear explicit dynamic analysis method,considers modeling of a 2D V-shape rigid wedge impacting on a calm water surface vertically with the algorithm of Arbitrary Lagrangian-Eulerian(the flow fields are modeled as Eulerian,while the structure is modeled as Lagrangian)and the penalty based coupling algorithm which is applied to control the fluid-structure interaction.Through the numerical simulation,pressure distribution on the bottom of the wedge is analysed,and the influence of the mesh density,contact stiffness and damping coefficient on the numerical results is discussed.Comparisons between numerical result and analytical solution of Wagner show consistency,which verified the reliability of this numerical simulation method.