https://doi.org/10.1140/epjd/e2014-50211-7
Regular Article
Gyroaverage operator for a polar mesh*
1
IRMA, Université de Strasbourg, 67000
Strasbourg,
France
2
Max-Planck-Institut für Plasmaphysik, 85748
Garching,
Germany
3
Inria-Rennes Bretagne Atlantique, IPSO team et IRMAR, Université
de Rennes 1, 35000
Rennes,
France
4
CEA/DSM/IRFM, Association Euratom-CEA Cadarache,
13108
Saint-Paul-lez-Durance,
France
5
Maison de la simulation, CEA Saclay, 91191
Gif sur Yvette,
France
a
e-mail: mehrenbe@math.unistra.fr
Received: 15 March 2014
Received in final form: 1 August 2014
Published online: 16 January 2015
In this work, we are concerned with numerical approximation of the gyroaverage operators arising in plasma physics to take into account the effects of the finite Larmor radius corrections. The work initiated in reference [N. Crouseilles, M. Mehrenberger, H. Sellama, CiCP 8, 484 (2010)] is extended here to polar geometries. A direct method is proposed in the space configuration which consists in integrating on the gyrocircles using interpolation operator (Hermite or cubic splines). Numerical comparisons with a standard method based on a Padé approximation are performed: (i) with analytical solutions; (ii) considering the 4D drift-kinetic model with one Larmor radius and (iii) on the classical linear DIII-D benchmark case [A. Dimits et al., Phys. Plasmas 7, 969 (2000)]. In particular, we show that in the context of a drift-kinetic simulation, the proposed method has similar computational cost as the standard method and its precision is independent of the radius.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2015