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DOE OSTI · 22490160

Two-fluid equilibrium with flow: FLOW2

Betti, R.
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Abstract

The effects of finite macroscopic velocities on axisymmetric ideal equilibria are examined using the two-fluid (ions and electrons) model. A new equilibrium solver, the code FLOW2, is introduced for the two-fluid model and used to investigate the importance of various flow patterns on the equilibrium of tight aspect ratio (NSTX) and regular tokamak (DIII-D) configurations. Several improvements to the understanding and calculation of two-fluid equilibria are presented, including an analytical and numerical proof of the single-fluid and static limits of the two-fluid model, a discussion of boundary conditions, a user-friendly free-function formulation, and the explicit evaluation of velocity components normal to magnetic surfaces.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGYASPECT RATIOAXIAL SYMMETRYBOUNDARY CONDITIONSDOUBLET-3 DEVICEELECTRONSEQUILIBRIUMF CODESFLUIDSIONSMAGNETIC SURFACESNSTX DEVICE

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Betti, R.. 2015-09-15. Two-fluid equilibrium with flow: FLOW2. https://doi.org/10.1063/1.4929854

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