The nonconforming virtual element method for parabolic problems

The nonconforming virtual element method for the parabolic problem is developed in this paper, where the semi-discrete and fully discrete formulations are presented. In order to analyze the convergence of the method, we construct a projection operator in the sense of the energy norm and give the corresponding error estimates in the L-2 norm and broken H-1 semi-norm. With the help of the energy projection operator, we prove the optimal convergence of the nonconforming virtual element method in the semi-discrete and fully discrete formulations, respectively. Finally, we investigate the convergence of the nonconforming virtual element method by some numerical examples, which verify the theoretical results. (C) 2019 IMACS. Published by Elsevier B.V. All rights reserved.