Functional A Posteriori Error Estimates for the Parabolic Obstacle Problem

The paper is concerned with functional-Type a posteriori estimates for the initial boundary value problem for a parabolic partial differential equation with an obstacle. We deduce a guaranteed and computable bound of the distance between the exact minimizer and any function from the admissible (energy) class of functions. Applications to the analysis of modeling errors caused by data implification are discussed. An important case of time incremental approximations is specially studied. Numerical examples presented in the last section show how the estimates work in practice. © 2022 Walter de Gruyter GmbH, Berlin/Boston.