Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

A Jacobian-free Multigrid Preconditioner for Discontinuous Galerkin Methods Applied to Atmospheric Flows

Birken, Philipp LU ; Dedner, Andreas and Klöfkorn, Robert LU orcid (2025) In GEM - International Journal on Geomathematics 17(1).
Abstract

Discontinuous Galerkin (DG) methods are promising high order discretizations for unsteady compressible flows. Here, we focus on Numerical Weather Prediction (NWP). These flows are characterized by a fine resolution in z-direction and low Mach numbers, making the system stiff. Thus, implicit time integration is required and for this a fast, highly parallel, low-memory iterative solver for the resulting algebraic systems. As a basic framework, we use inexact Jacobian-Free Newton-GMRES with a preconditioner. For low order finite volume discretizations, multigrid methods have been successfully applied to steady and unsteady fluid flows. However, for high order DG methods, such solvers are currently lacking. This motivates our research to... (More)

Discontinuous Galerkin (DG) methods are promising high order discretizations for unsteady compressible flows. Here, we focus on Numerical Weather Prediction (NWP). These flows are characterized by a fine resolution in z-direction and low Mach numbers, making the system stiff. Thus, implicit time integration is required and for this a fast, highly parallel, low-memory iterative solver for the resulting algebraic systems. As a basic framework, we use inexact Jacobian-Free Newton-GMRES with a preconditioner. For low order finite volume discretizations, multigrid methods have been successfully applied to steady and unsteady fluid flows. However, for high order DG methods, such solvers are currently lacking. This motivates our research to construct a Jacobian-free preconditioner for high order DG discretizations. The preconditioner is based on a multigrid method constructed for a low order finite volume discretization defined on a subgrid of the DG mesh. We design a computationally efficient and mass conservative mapping between the grids. As smoothers, explicit Runge-Kutta pseudo time iterations are used, which can be implemented in parallel in a Jacobian-free low-memory manner. We consider DG Methods for the Euler equations and for viscous flow equations in 2D, both with gravity, in a well balanced formulation. Numerical experiments in the software framework DUNE-FEM on atmospheric flow problems show the benefit of this approach.

(Less)
Please use this url to cite or link to this publication:
author
; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
DG, DUNE, DUNE-FEM, FV, Implicit, Jacobian-free, Multigrid, Numerical weather prediction, Preconditioner
in
GEM - International Journal on Geomathematics
volume
17
issue
1
article number
2
publisher
Springer
external identifiers
  • scopus:105026251459
ISSN
1869-2672
DOI
10.1007/s13137-025-00279-y
language
English
LU publication?
yes
additional info
Publisher Copyright: © The Author(s) 2025.
id
ab290390-d42d-4c49-935e-5b9ed4c98bd9
date added to LUP
2026-03-09 17:01:06
date last changed
2026-03-09 17:02:08
@article{ab290390-d42d-4c49-935e-5b9ed4c98bd9,
  abstract     = {{<p>Discontinuous Galerkin (DG) methods are promising high order discretizations for unsteady compressible flows. Here, we focus on Numerical Weather Prediction (NWP). These flows are characterized by a fine resolution in z-direction and low Mach numbers, making the system stiff. Thus, implicit time integration is required and for this a fast, highly parallel, low-memory iterative solver for the resulting algebraic systems. As a basic framework, we use inexact Jacobian-Free Newton-GMRES with a preconditioner. For low order finite volume discretizations, multigrid methods have been successfully applied to steady and unsteady fluid flows. However, for high order DG methods, such solvers are currently lacking. This motivates our research to construct a Jacobian-free preconditioner for high order DG discretizations. The preconditioner is based on a multigrid method constructed for a low order finite volume discretization defined on a subgrid of the DG mesh. We design a computationally efficient and mass conservative mapping between the grids. As smoothers, explicit Runge-Kutta pseudo time iterations are used, which can be implemented in parallel in a Jacobian-free low-memory manner. We consider DG Methods for the Euler equations and for viscous flow equations in 2D, both with gravity, in a well balanced formulation. Numerical experiments in the software framework DUNE-FEM on atmospheric flow problems show the benefit of this approach.</p>}},
  author       = {{Birken, Philipp and Dedner, Andreas and Klöfkorn, Robert}},
  issn         = {{1869-2672}},
  keywords     = {{DG; DUNE; DUNE-FEM; FV; Implicit; Jacobian-free; Multigrid; Numerical weather prediction; Preconditioner}},
  language     = {{eng}},
  month        = {{12}},
  number       = {{1}},
  publisher    = {{Springer}},
  series       = {{GEM - International Journal on Geomathematics}},
  title        = {{A Jacobian-free Multigrid Preconditioner for Discontinuous Galerkin Methods Applied to Atmospheric Flows}},
  url          = {{http://dx.doi.org/10.1007/s13137-025-00279-y}},
  doi          = {{10.1007/s13137-025-00279-y}},
  volume       = {{17}},
  year         = {{2025}},
}