Gyroviscous force in plasmas with strong EB flow

Miyato, Naoaki; Scott, B. D.*; Yagi, Masatoshi

Reduced fluid models are widely used for nonlinear simulations of magnetised fusion plasmas. Traditionally they are derived from more rigorous fluid model such as the Braginskii model by imposing assumptions like low frequency perturbations. In the traditional derivation, calculation of the gyroviscosity is needed and it is very complicated. Alternatively reduced fluid models can be derived from fluid moment equations of reduced kinetic models. We can bypass the calculation of the gyroviscosity in the alternative method. Recently we derived a reduced kinetic model for plasmas with large EB velocity. Based on the reduced kinetic model, reduced fluid equations are derived and the gyroviscous force is obtained by comparing the reduced equations and fluid equations without reduction.