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arXiv · 1302.0676

Non-local approach to kinetic effects on parallel transport in fluid models of the scrape-off layer

John Omotani·Ben Dudson
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Abstract

By using a non-local model, fluid simulations can capture kinetic effects in the parallel electron heat-flux better than is possible using flux limiters in the usual diffusive models. Non-local and diffusive models are compared using a test case representative of an ELM crash in the JET SOL, simulated in one dimension. The non-local model shows substantially enhanced electron temperature gradients, which cannot be achieved using a flux limiter. The performance of the implementation, in the BOUT++ framework, is also analysed to demonstrate its suitability for application in three-dimensional simulations of turbulent transport in the SOL.

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John Omotani, Ben Dudson. 2013-07-15. Non-local approach to kinetic effects on parallel transport in fluid models of the scrape-off layer. https://doi.org/10.1088/0741-3335%2F55%2F5%2F055009

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