Dominant two-fluid magnetohydrodynamic instabilities in CFETR upgrade phase-I scenario in presence of perfect conducting wall. (27th February 2019)

• Record Type: Journal Article
• Authors: Cheng, Shikui; Zhu, Ping; Banerjee, Debabrata; Yan, Xingting
• Other Names: collab.
• Is Part Of: Plasma physics and controlled fusion. Volume 61:Number 4(2019)
• Publication Date: 2019-02-27
• Subjects: CFETR -- macroscopic stability -- two-fluid MHD -- NIMROD -- conducting wall; Plasma (Ionized gases) -- Periodicals; Controlled fusion -- Periodicals; 530.44
• DOI: 10.1088/1361-6587/ab0090
• Languages: English
• ISSNs: 0741-3335

Abstract

Abstract: The dominant two-fluid magnetohydrodynamic (MHD) stabilities of China Fusion Engineering Test Reactor upgrade phase-I baseline equilibria in presence of perfect conducting wall have been evaluated using the initial value code NIMROD. Our MHD simulations show that for equilibrium with q axis < 1, high- n edge localized modes are slightly stabilized by toroidal shear flow, and n = 1 mode is found to be unstable in the core region with the characteristic of sawtooth instability. For q axis > 2 equilibrium, all modes are found to be unstable but edge localized both in single-fluid and two-fluid MHD models. Specifically for n ≤ 13 modes, the two-fluid MHD model gives a slightly higher growth rate than the single-fluid MHD model, while for n > 13 modes, this trend becomes the opposite, which means the two-fluid MHD model is needed for high- n mode analysis. In addition, n = 1–10 modes are found to be more unstable with increasing wall position and eventually their growth rates approach values in the no-wall limit.