Progress with the COGENT Edge Kinetic Code: Collision operator options

Dorf, M. A.; Cohen, R. H.; Compton, J. C.; Dorr, M.; Rognlien, T. D.; Angus, J.; Krasheninnikov, S.; Colella, P.; Martin, D.; McCorquodale, P.

doi:10.1002/ctpp.201210042

DOE OSTI · 1248305

Progress with the COGENT Edge Kinetic Code: Collision operator options

Dorf, M. A.·Cohen, R. H.·Compton, J. C.·Dorr, M.·Rognlien, T. D.·Angus, J.·Krasheninnikov, S.·Colella, P.·Martin, D.·McCorquodale, P.

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Abstract

In this study, COGENT is a continuum gyrokinetic code for edge plasmas being developed by the Edge Simulation Laboratory collaboration. The code is distinguished by application of the fourth order conservative discretization, and mapped multiblock grid technology to handle the geometric complexity of the tokamak edge. It is written in v∥-μ (parallel velocity – magnetic moment) velocity coordinates, and making use of the gyrokinetic Poisson equation for the calculation of a self-consistent electric potential. In the present manuscript we report on the implementation and initial testing of a succession of increasingly detailed collision operator options, including a simple drag-diffusion operator in the parallel velocity space, Lorentz collisions, and a linearized model Fokker-Planck collision operator conserving momentum and energy (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY 97 MATHEMATICS AND COMPUTING edge gyrokinetic kinetic plasma simulation

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Dorf, M. A., Cohen, R. H., Compton, J. C., Dorr, M., Rognlien, T. D., Angus, J., Krasheninnikov, S., Colella, P., Martin, D., McCorquodale, P.. 2012-06-27. Progress with the COGENT Edge Kinetic Code: Collision operator options. https://doi.org/10.1002/ctpp.201210042

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