A Superconvergent Ensemble HDG Method for Parameterized Convection Diffusion Equations
This work provides the first optimal L^2 convergence result for ensemble HDG methods, benefiting researchers solving parameterized PDEs with reduced computational cost.
The authors develop an ensemble HDG method for parameterized convection-diffusion PDEs, achieving an optimal L^2 convergence rate on general polygonal domains and a superconvergent rate after postprocessing, reducing computational cost and storage.
In this paper, we first devise an ensemble hybridizable discontinuous Galerkin (HDG) method to efficiently simulate a group of parameterized convection diffusion PDEs. These PDEs have different coefficients, initial conditions, source terms and boundary conditions. The ensemble HDG discrete system shares a common coefficient matrix with multiple right hand side (RHS) vectors; it reduces both computational cost and storage. We have two contributions in this paper. First, we derive an optimal $L^2$ convergence rate for the ensemble solutions on a general polygonal domain, which is the first such result in the literature. Second, we obtain a superconvergent rate for the ensemble solutions after an element-by-element postprocessing under some assumptions on the domain and the coefficients of the PDEs. We present numerical experiments to confirm our theoretical results.