Suite of verification test problems for edge turbulence simulations

Abstract

We present a suite of test problems that are used for verification of the edge turbulence code BOUT. BOUT is an electromagnetic fluid turbulence code for tokamak edge plasma that performs time integration of reduced Braginskii plasma fluid equations, using spatial discretization in realistic geometry and employing a standard ODE integration package PVODE. Recently the code underwent a substantial redesign and extensive verification testing. In the verification process, a series of linear and nonlinear test problems was applied to BOUT targeting different subgroups of physical terms. The tests include reproducing basic electrostatic and electromagnetic plasma modes in simplified geometry, axisymmetric benchmarks against the 2D edge code UEDGE in the actual DIII-D tokamak divertor geometry. Successful passing of these tests by BOUT gives strong evidence that equations in the code are solved correctly. Although the tests were developed specifically for the BOUT code they can well be applied for verification of other codes used for simulations of edge turbulence. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.