The Boundary Element Method (BEM) is a numerical technique for solving Boundary Integral Equations. This is our default method for solving as we find it to be the fastest and most accurate general purpose solution method. From version 6.1 and higher, users have other options (e.g. a Finite/Boundary Element hybrid in 2D programs) to deal with specific issues since no single solution method is the best for every problem type.
In the BEM technique, electromagnetic, thermal and structural phenomena are mathematically described by appropriate equation systems (e.g. Maxwell’s equations for electromagnetics ) in integral form. Enforcing the boundary conditions along the material interfaces allows one to obtain a set of boundary integral equations with the unknowns as the equivalent sources or field variables along the interfaces. One may then discretize the boundaries to boundary elements, represent the unknowns on elements, and obtain a system of linear equations. In this way BEM solves a given problem. All field variables at any point in space may be obtained by performing integrations associated with the equivalent sources or fields on the boundaries.