Title
A high-order semi-explicit discontinuous Galerkin solver for 3D incompressible flow with application to DNS and LES of turbulent channel flow.
Abstract
We present an efficient discontinuous Galerkin scheme for simulation of the incompressible Navier–Stokes equations including laminar and turbulent flow. We consider a semi-explicit high-order velocity-correction method for time integration as well as nodal equal-order discretizations for velocity and pressure. The non-linear convective term is treated explicitly while a linear system is solved for the pressure Poisson equation and the viscous term. The key feature of our solver is a consistent penalty term reducing the local divergence error in order to overcome recently reported instabilities in spatially under-resolved high-Reynolds-number flows as well as small time steps. This penalty method is similar to the grad–div stabilization widely used in continuous finite elements. We further review and compare our method to several other techniques recently proposed in literature to stabilize the method for such flow configurations. The solver is specifically designed for large-scale computations through matrix-free linear solvers including efficient preconditioning strategies and tensor-product elements, which have allowed us to scale this code up to 34.4 billion degrees of freedom and 147,456 CPU cores. We validate our code and demonstrate optimal convergence rates with laminar flows present in a vortex problem and flow past a cylinder and show applicability of our solver to direct numerical simulation as well as implicit large-eddy simulation of turbulent channel flow at Reτ=180 as well as 590.
Year
DOI
Venue
2017
10.1016/j.jcp.2017.07.039
Journal of Computational Physics
Keywords
Field
DocType
Discontinuous Galerkin,Incompressible Navier–Stokes equations,Turbulent flow,Matrix-free implementation,Splitting method
Direct numerical simulation,Discontinuous Galerkin method,Mathematical optimization,Mathematical analysis,Laminar flow,Turbulence,Solver,Incompressible flow,Open-channel flow,Mathematics,Penalty method
Journal
Volume
ISSN
Citations 
348
0021-9991
5
PageRank 
References 
Authors
0.45
25
4
Name
Order
Citations
PageRank
Benjamin Krank150.45
Niklas Fehn2111.26
Wolfgang A. Wall36122.07
Martin Kronbichler432331.00