Kinematic dynamos using constrained transport with high order Godunov schemes and adaptive mesh refinement

Romain Teyssiera,b, Sebastien Fromangc, Emmanuel Dormyd,e,b

a CEA/DSM/DAPNIA/Service d'Astrophysique, Gif-sur-Yvette, 91191 Cedex, France
b Institut d'Astrophysique de Paris, 98bis Bd Arago, 75014 Paris, France
c Astronomy Unit, Queen Mary, University of London, Mile End Road, London E1 4NS, UK
d Laboratoire de Physique Statistique, E.N.S., 24, rue Lhomond, 75231 Paris Cedex 05, France
e Departement de Geomagnetisme, I.P.G.P./C.N.R.S., 4 Place Jussieu, 75252 Paris Cedex 05, France

Journal of Computational Physics, Volume 218, Issue 1 , 10 October 2006, Pages 44-67

Abstract. We propose to extend the well-known MUSCL-Hancock scheme for Euler equations to the induction equation modeling the magnetic field evolution in kinematic dynamo problems. The scheme is based on an integral form of the underlying conservation law which, in our formulation, results in a Òfinite-surfaceÓ scheme for the induction equation. This naturally leads to the well-known Òconstrained transportÓ method, with additional continuity requirement on the magnetic field representation. The second ingredient in the MUSCL scheme is the predictor step that ensures second order accuracy both in space and time. We explore specific constraints that the mathematical properties of the induction equations place on this predictor step, showing that three possible variants can be considered. We show that the most aggressive formulations (referred to as C-MUSCL and U-MUSCL) reach the same level of accuracy as the other one (referred to as RungeÐKutta), at a lower computational cost. More interestingly, these two schemes are compatible with the adaptive mesh refinement (AMR) framework. It has been implemented in the AMR code RAMSES. It offers a novel and efficient implementation of a second order scheme for the induction equation. We have tested it by solving two kinematic dynamo problems in the low diffusion limit. The construction of this scheme for the induction equation constitutes a step towards solving the full MHD set of equations using an extension of our current methodology.

Keywords: Magnetohydrodynamics and electrohydrodynamics; Hydrodynamic and hydromagnetic problems; Finite difference methods; Induction equation; Magnetohydrodynamics; Godunov scheme; Adaptive mesh refinement; Numerical schemes