A New Penalty Method for Elliptic Quasivariational Inequalities

We consider a class of elliptic quasivariational 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∈ K. The criterion provides necessary and sufficient conditions which guarantee that an arbitrary sequence {u_n}⊂ X converges to the solution u. Then, we consider a sequence { P_n} of unconstrained variational-hemivariational inequalities governed by a sequence of parameters {λ_n}⊂ℝ_+. We use our criterion to deduce that, if for each n∈ℕ the term u_n represents a solution of Problem P_n, then the sequence {u_n} converges to u as λ_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.