Active stabilization of error field penetration via control field and bifurcation of its stable frequency range. (4th August 2017)

• Record Type: Journal Article
• Authors: Inoue, S.; Shiraishi, J.; Takechi, M.; Matsunaga, G.; Isayama, A.; Hayashi, N.; Ide, S.
• Is Part Of: Nuclear fusion. Volume 57:Number 11(2017:Nov.)
• Publication Date: 2017-08-04
• Subjects: forced magnetic reconnection -- error field penetration -- control field -- locked mode; Nuclear fusion -- Periodicals; 621.48405
• DOI: 10.1088/1741-4326/aa7dc3
• Languages: English
• ISSNs: 0029-5515

Abstract

Abstract: An active stabilization effect of a rotating control field against an error field penetration is numerically studied. We have developed a resistive magnetohydrodynamic code 'AEOLUS-IT', which can simulate plasma responses to rotating/static external magnetic field. Adopting non-uniform flux coordinates system, the AEOLUS-IT simulation can employ high magnetic Reynolds number condition relevant to present tokamaks. By AEOLUS-IT, we successfully clarified the stabilization mechanism of the control field against the error field penetration. Physical processes of a plasma rotation drive via the control field are demonstrated by the nonlinear simulation, which reveals that the rotation amplitude at a resonant surface is not a monotonic function of the control field frequency, but has an extremum. Consequently, two 'bifurcated' frequency ranges of the control field are found for the stabilization of the error field penetration.