Boundary Element Program Research Articles

CGHYDRO (a boundary element program for the computation of hydrodynamic forces on long floating structures)

CGHYDRO is a computer program, based on boundary element methods, for the computation of the hydrodynamic forces (added mass, added damping, and exciting wave force), on long floating structures. The 3-dimensional effects are taken into account in the computation. The program can be used for any kind of cross section shape and sea bottom configuration. The boundary element solution produces a small and efficient computer code.

Finite‐element and boundary‐element analysis of craze micromechanics

AbstractThe two numerical methods are used to estimate craze surface displacements and stresses for both isolated crazes and crazes at crack tips. The results are compared with the predictions of craze micromechanics models. The investigation includes the computation of the craze surface stress profile required to maintain a given craze opening displacement profile. The boundary element program requires less computer time than the finite element one, and similar results are obtained. The analysis also considers the craze surface displacement profile corresponding to an assumed craze surface stress distribution. The element methods produce results which are approximately the same as those obtained using the model of Verheulpen‐Heymans and Bauwens.

On the implementation of elasto-plastic boundary element analysis

This paper discusses efficient methods for implementing elasto-plastic boundary element programs. A solution strategy based on minimizing the number of computer operations for each iteration of the elasto-plastic algorithm is described for both the direct and indirect formulations. Interior strains may be computed from the integral equations but this is shown to be an order of magnitude greater in terms of operations (excluding evaluation of the kernel functions) than obtaining strains using a finite difference procedure. Cells existing for the volume integrations associated with the initial stress terms may be used for the differencing process. The assumption of constant stress across cells has been used and found adequate for many problems but a linear variation, with stresses being computed at cell nodes, may prove better in certain cases. All integrations must be performed numerically. A simplified flow chart of the algorithm is presented and typical solutions for two test problems are given. Finally a comparison between finite element and boundary element solution times for several problems is attempted, it seems that solution times are similar.