A posteriori error estimates for two-phase obstacle problem

0444082 - ÚTIA 2016 RIV US eng J - Journal Article
Repin, S. - Valdman, Jan
A posteriori error estimates for two-phase obstacle problem.
Journal of Mathematical Sciences. Roč. 107, č. 2 (2015), s. 324-335. ISSN 1072-3374
R&D Projects: GA ČR GA13-18652S
Institutional support: RVO:67985556
Keywords : two-phase obstacle problem * a posteriori error estimate * finite element method * variational inequalities
Subject RIV: BA - General Mathematics
http://library.utia.cas.cz/separaty/2015/MTR/valdman-0444082.pdf

For the two-phase obstacle problem we derive the basic error identity which yields natural measure of the distance to the exact solution. For this measure we derive a computable majorant valid for any function in the admissible (energy) class of functions. It is proved that the majorant vanishes if and only if the function coincides with the minimizer. It is shown that the respective estimate has no gap, so that accuracy of any approximation can be evaluated with any desired accuracy.
Permanent Link: http://hdl.handle.net/11104/0246679