Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4), 21 (1994), 193-212.
Ricardo H. Nochetto
Department of Mathematics
University of Maryland, College Park
College Park, MD 20742, USA
Maurizio Paolini
Dipartimento di Matematica
Universita di Milano
Milano, 20133, Italy
Claudio Verdi
Dipartimento di Matematica
Universita di Milano
Milano, 20133, Italy
We study a double obstacle problem for a singularly perturbed reaction diffusion equation with a small parameter $\eps>0$. This problem is viewed as an approximation for the classical mean curvature flow. We derive an optimal error estimate of order $\O(\eps^2)$ for the interfaces, which is valid before the onset of singularities. The proof is based on constructing suitable sub and supersolutions, and using a modified distance function that incorporates a shape correction.