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arXiv · 0905.0086

Reevaluation of the Braginskii viscous force for toroidal plasma

Robert W. Johnson
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Abstract

The model by Braginskii for the viscous stress tensor is used to determine the shear and gyroviscous forces acting within a toroidally confined plasma. Comparison is made to a previous evaluation which contains an inconsistent treatment of the radial derivative and neglects the effect of the pitch angle. Parallel viscosity contributes a radial shear viscous force which may develop for sufficient vertical asymmetry to the ion velocity profile. An evaluation is performed of this radial viscous force for a tokamak near equilibrium which indicates qualitative agreement between theory and measurement for impure plasma discharges with strong toroidal flow.

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Robert W. Johnson. 2011-11-03. Reevaluation of the Braginskii viscous force for toroidal plasma. https://doi.org/10.1017/s0022377811000250

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