Boundary Element Analysis Of Problems Research Articles

Isogeometric boundary element analysis of problems in potential flow

The aim of the paper is to show that the isogeometric Boundary Element Method (isoBEM) has advantages over other numerical methods when applied to problems in potential flow. The problems presented here range from the flow past an obstacle to confined and unconfined seepage problems in isotropic and anisotropic media. It is shown how accurate results can be obtained with very few unknowns. The superior capability of NURBS to describe geometry and the variation of the unknowns is exploited.

Advanced Boundary Element analysis of geotechnical problems with geological inclusions

In this work a novel approach is presented for the Boundary Element analysis of problems in geomechanics. Firstly, Non-Uniform Rational B-Spines (NURBS) are used for the description of the geometry and for the approximation of the unknowns. This results in a significant decrease in the number of parameters used for an accurate description of the geometry as well as a decrease in the number of degrees of freedom required for good quality results. Secondly, NURBS are also used for the description of the geometry of geological inclusions, which can have properties different to the rock mass and can experience inelastic behavior.After a short introduction to the theory, some details of implementation are shown. On test examples, involving elastic homogeneous domains, it is first shown that the method delivers accurate results with fewer parameters and number of unknowns as compared with conventional analysis. Solutions are compared to either known solutions or with conventional BEM analyses. Geological inclusions are introduced next and results of test examples are compared with Finite Element analyses. Finally a practical example is shown.

Treatment of bimaterial interface crack problems using the boundary element method

Quadratic quarter-point crack-tip elements are introduced in the two-dimensional boundary element analysis of problems in which a crack lies along the interface of dissimilar elastic materials. Such problems present some modelling difficulties using conventional procedures because the stresses are oscillatorily singular in the neighbourhood of the crack-tip. Analytical expressions relating the stress intensity factor to the computed displacements of the crack-tip element or to the computed crack-tip nodal tractions are derived and their veracity demonstrated with some examples. Numerical results, compared with exact solutions where possible, are accurate even with relatively coarse mesh designs.