A NEW PENALTY METHOD FOR ELLIPTIC VARIATIONAL INEQUALITIES

We consider a class of elliptic variational inequalities in a reflexive Banach space X for which we recall a convergence criterion obtained in [10]. Each inequality P in the class is governed by a set of constraints K and has a unique solution u is an element of K. The criterion provides necessary and sufficient conditions which guarantee that an arbitrary sequence {un} subset of X converges to the solution u. Then, we consider a sequence {Pn} of unconstrained variationalhemivariational inequalities governed by a sequence of parameters {lambda n} subset of R+. We use our criterion to deduce that, if for each n is an element of N the term un represents a solution of Problem Pn, then the sequence {un} converges to u as lambda n -> 0. We apply our abstract results in the study of an elastic frictional contact problem with unilateral constraints and provide the corresponding mechanical interpretations. We also present numerical simulation in the study of a two-dimensional example which represents an evidence of our convergence results.