Abstract

This paper considers the analytical technique of element integral in the boundary element method with constant element for 3D Laplace and Stokes flow problems. For 3D Laplace problems, the analytical integral formulae, which are valid for an arbitrary source point, are derived. For 3D Stokes flow problems, analytical evaluation of the integrals, which the source point and the boundary element are in the same plane, are proposed. These analytical formulae are applicable for arbitrary convex polygonal planar elements. Numerical examples are given to validate the improvement on accuracy.