2022/06/24 by Zhang, Baiju, Zhang, Zhimin
#FOS: Mathematics #Numerical Analysis (math.NA)
paper · doi:10.48550/arxiv.2206.12107
We introduce and analyze a robust nonconforming finite element method for a three dimensional singularly perturbed quad-curl model problem. For the solution of the model problem, we derive proper a priori bounds, based on which, we prove that the proposed finite element method is robust with respect to the singular perturbation parameter ε and the numerical solution is uniformly convergent with order h1/2. In addition, we investigate the effect of treating the second boundary condition weakly by Nitsche's method. We show that such a treatment leads to sharper error estimates than imposing the boundary condition strongly when the parameter ε< h. Finally, numerical experiments are provided to illustrate the good performance of the method and confirm our theoretical predictions.