Tokamak edge modeling and comparison with experiment in ASDEX

TLDR

Edge modeling in tokamaks focuses on poloidal divertor physics, axisymmetric and weakly perturbed configurations, and ongoing efforts to validate models against experimental data. The study employs ASDEX measurements to benchmark edge models, examining fundamental equations, transport coefficients, thermoelectric effects, density limits, and 3D perturbations such as magnetic field ergodization.

Abstract

A survey of edge modeling and its application to running experiments is given with emphasis on poloidal divertors. The basic edge structure in axisymmetric and weakly perturbed tokamaks is first discussed. The ongoing modeling activities and the status of model validation are outlined. ASDEX data are mostly used for comparison, since sufficiently detailed and coherent edge measurements are not available in the literature for most experiments. Edge physics issues discussed in more detail are the basic model equations, parallel and perpendicular transport coefficients, thermoelectric effects, edge density limit and three-dimensional perturbations including magnetic field ergodization.