Analysis of a class of globally divergence-free HDG methods for stationary Navier-Stokes equations

04/07/2022

∙

by   Gang Chen, et al.

∙

0

∙

share

This paper analyzes a class of globally divergence-free (and therefore pressure-robust) hybridizable discontinuous Galerkin (HDG) finite element methods for stationary Navier-Stokes equations. The methods use the 𝒫_k/𝒫_k-1 (k≥1) discontinuous finite element combination for the velocity and pressure approximations in the interior of elements, and piecewise 𝒫_k/𝒫_k for the trace approximations of the velocity and pressure on the inter-element boundaries. It is shown that the uniqueness condition for the discrete solution is guaranteed by that for the continuous solution together with a sufficiently small mesh size. Based on the derived discrete HDG Sobolev embedding properties, optimal error estimates are obtained. Numerical experiments are performed to verify the theoretical analysis.