A New Infinite Element for Finite Element Analysis of Three Dimensional Unbounded Field Problems

抄録

A simple and efficient infinite element has been developed for the finite element analysis of three dimensional field problems whose domain extends to infinity. The formulation is based on the assumed displacement hybrid finite element model. The present element has the following features: (1) Since it requires no interpolation nodes in the exterior region, both the number of total degrees of freedom and the bandwidth of the global stiffness matrix remain exactly the same as those of interior elements. (2) The generation of the element stiffness matrix requires neither the matrix inversion nor the integration for the direction extending to infinity. (3) The computational effort needed for the entire process is almost the same as that for a corresponding bounded problem. (4) It can be used in conjunction with conventional interior elements. Numerical results for several three dimensional infinite domain problems are presented.