Speaker
Description
Ion cyclotron resonance heating (ICRH) is a routinely used method to bring plasmas to fusion relevant temperatures in magnetic confinement fusion machines (see e.g. [1]). Properly modelling the dielectric response is a challenge both from the physics and the computational point of view. More often than not simplifications are made, first of all by truncating the dielectric tensor at the leading order terms in finite Larmor radius corrections and secondly by simplifying the geometry. A new solver is under development at LPP-ERM/KMS to help understand the ICRH wave propagation and damping in stellarators such as Wendelstein-7X. It is based on the philosophy pioneered by Jaeger [2] for the AORSA code, and intends to complement the physics described in the SCENIC code (see e.g. [3]) with a rigorous computation of the wave polarisation at higher cyclotron harmonics. The key idea here is to assess the importance of higher order finite Larmor radius corrections while keeping both the zero order distribution functions as well as the geometry simple and given. In anticipation of its exploitation for the 3D fully inhomogeneous plasmas of W-7X, a focal point of the present work is to develop and test a technique for solving the relevant wave equation with as minimal as possible CPU requirements while keeping the full richness of the kinetic corrections. Preliminary results of this code are provided and discussed.
References
[1] E. Lerche et al., Nuclear Fusion 54 (2014) 073006
[2] E.F. Jaeger et al., Physics of Plasmas, 8 (2001) 1573
[3] M. Jucker et al., Computer Physics Communications 182 (2011) 912
