Unconfined Flow through Porous Media Using B-Spline Boundary Elements

The boundary element method (BEM) is now established as a suitable and efficient technique for the analysis of ground-water flow problems. However, as in other discretization procedures, inaccuracies can be introduced as a result of the lack of derivative continuity between adjacent elements. Continuity of the derivatives of the main variable is important to obtain a good representation of moving boundaries with iterative or time-marching schemes. A recently developed BEM formulation, using cubic B-splines, provides as much as C2 continuity between adjacent elements. This formulation is applied in herein to steady-state and transient unconfined flow in homogeneous and nonhomogeneous media.