Numerical matching scheme for linear magnetohydrodynamic stability analysis

線型MHD安定性解析のための数値接続解法

影井 康弘; 徳田 伸二

Kagei, Yasuhiro; Tokuda, Shinji

A new matching scheme for linear magnetohydrodynamic (MHD) stability analysis is proposed in a form that the numerical implementation is tractable. The scheme divides the plasma region into outer regions and inner layers, as in the conventional matching method. However the outer regions do not contain any rational surface as their terminal points; an inner layer contains a rational surface as an interior point. The MHD equation employed in the layers is solved as an evolution equation in time, and the full implicit scheme is used to yield an inhomogeneous differential equation for space coordinates. The matching conditions are derived from the conditions that the radial component of the solution in the layer be smoothly connected to those in the outer regions at the terminal points. The proposed scheme is applied to the linear ideal MHD equation in a cylindrical configuration, and is proved to be effective from the view point of numerical scheme.