An penalty approach for elliptic problems on non-matching grids.

Joseph Pasciak, R.D. Lazarov, J. Schoberl and P. Vassilevski

Dept. of Mathematics, Texas A&M University, College Station, TX 77840


In this talk I will consider approximations to second order elliptic problems on non-matching grids which utilize penalty terms to impose interface continuity. This approach avoids the introduction and construction of multiplier subspaces commonly associated with mortar finite element techniques. I will present results which show that in the case of piecewise linear finite elements, the penalty formulation leads to almost optimal approximation.