A Reynolds-SemiRobust Method with Hybrid Velocity and Pressure for the Unsteady Incompressible Navier–Stokes Equations

In this paper we propose and analyze a new finite element method for the solution of the two- and three-dimensional incompressible Navier-Stokes equations based on a hybrid discretization of both the velocity and pressure variables. The proposed method is pressure-robust, i.e., irrotational forcing terms do not affect the approximation of the velocity, and Reynolds quasi-robust, with error estimates that, for smooth enough exact solutions, do not depend on the inverse of the viscosity. We carry out an in-depth convergence analysis highlighting preasymptotic convergence rates and validate the theoretical findings with a complete set of numerical experiments.