流体固体动力耦合分析的有限元法

应用有限元法探讨了流体、固体接触界面由无限接触点对组成,并以接触点对的瞬态接触内力作为待定变量的流体固体动力耦合模型的数值求解方法。分析了流体、固体域插值函数的特点,用二维八节点等参元及流固接触面上的接触点对单元,对流固耦合系统进行了离散化处理;并采用变分原理推导了反映流体固体动力相互作用机理的接触约束矩阵(或称动力耦合矩阵),建立了有限元控制方程,给出了完整的数值计算方法,研编了动力耦合系统的分析程序。数值计算结果与经典理论解误差很小,验证了动力耦合模型和有限元求解方法的正确性及其较高的计算精度。

FINITE ELEMENT METHOD FOR TRANSIENT ANALYSIS OF FLUID-STRUCTURE COUPLING PROBLEM

The transient analysis of fluid-structure coupling system is conducted using finite element method, in which the transient contact force of the unlimited contact points coupling in the contact interface between fluid and structure is taken as unknown variable. The 2-dimensional 8-node element and the contact point couple elements are used, based on the interpolating function feature in the fluid and structure domain. The fluid-structure coupling system is divided into elements, and the finite element equation with the contact constrain matrix that reflects the mechanism of interaction is derived from a variational principle. A computer program is developed for the transient analysis of fluid-solid coupling system. Numerical results are in excellent agreement with those of the available analytical solution.