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arXiv · 1609.06603

Towards nonaxisymmetry; initial results using the Flux Coordinate Independent method in BOUT++

Brendan Shanahan·Peter Hill·Ben Dudson
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Abstract

Fluid simulation of stellarator edge transport is difficult due to the complexities of mesh generation; the stochastic edge and strong nonaxisymmetry inhibit the use of field aligned coordinate systems. The recent implementation of the Flux Coordinate Independent method for calculating parallel derivatives in BOUT++ has allowed for more complex geometries. Here we present initial results of nonaxisymmetric diffusion modelling as a step towards stellarator turbulence modelling. We then present initial (non-turbulent) transport modelling using the FCI method and compare the results with analytical calculations. The prospects for future stellarator transport and turbulence modelling are discussed.

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Brendan Shanahan, Peter Hill, Ben Dudson. 2016-09-21. Towards nonaxisymmetry; initial results using the Flux Coordinate Independent method in BOUT++. https://doi.org/10.1088/1742-6596/775/1/012012

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