A Class of Embedded DG Methods for Dirichlet Boundary Control of Convection Diffusion PDEs
Provides a more efficient numerical method for solving boundary control problems in PDEs, but is an incremental improvement over existing HDG methods.
This work achieves optimal convergence rates for Dirichlet boundary control of convection-diffusion PDEs using embedded DG methods, which have fewer degrees of freedom than HDG methods, and introduces a simpler numerical analysis technique for low-regularity solutions.
We investigated an hybridizable discontinuous Galerkin (HDG) method for a convection diffusion Dirichlet boundary control problem in our earlier work [SIAM J. Numer. Anal. 56 (2018) 2262-2287] and obtained an optimal convergence rate for the control under some assumptions on the desired state and the domain. In this work, we obtain the same convergence rate for the control using a class of embedded DG methods proposed by Nguyen, Peraire and Cockburn [J. Comput. Phys. vol. 302 (2015), pp. 674-692] for simulating fluid flows. Since the global system for embedded DG methods uses continuous elements, the number of degrees of freedom for the embedded DG methods are smaller than the HDG method, which uses discontinuous elements for the global system. Moreover, we introduce a new simpler numerical analysis technique to handle low regularity solutions of the boundary control problem. We present some numerical experiments to confirm our theoretical results.