3D analysis of coupled thin-walled structural elements by means of standard boundary element formulations

Abstract

Recently, some improvements of the generic BE/BE coupling algorithm based on Krylov's solvers, proposed by the first author of this paper and outlined in previous papers, were carried out by including discontinuous boundary elements in the BE code. As a consequence of that, traction continuity conditions, necessary for simulating edges and corners at coupling interfaces in models based on continuous boundary elements, must no longer be taken into account. Thus, the respective BE models for complex 3D regions become considerably simpler. In this paper, a general description of the main features of the algorithm is furnished. In addition, some strategies for making the analysis of moderate thin-walled structural elements by means of three-dimensional standard BE formulations possible are presented. A study of the performance of the code is also shown, where mainly computational efficiency parameters such as response precision and CPU time for assembling the system of algebraic equations and solving it are commented. Engineering systems involving thin-walled elements, possibly containing cracks, are simulated. High-precision IMSL routines (available in FORTRAN compilers) are used to study the performance of the code. Strategies for improving the conditioning of the systems are also commented.