MHD activity in the ISX-B tokamak: experimental results and theoretical interpretation

Technical Report · Fri Jan 01 04:00:00 EST 1982

DOI:https://doi.org/10.2172/5333158· OSTI ID:5333158

Carreras, B A; Dunlap, J L; Bell, J D; Charlton, L A; Cooper, W A; Dory, R A; Hender, T C; Hicks, H R; Holmes, J A; Lynch, V E

The observed spectrum of MHD fluctuations in the ISX-B tokamak is clearly dominated by the n=1 mode when the q=1 surface is in the plasma. This fact agrees well with theoretical predictions based on 3-D resistive MHD calculations. They show that the (m=1; n=1) mode is then the dominant instability. It drives other n=1 modes through toroidal coupling and n>1 modes through nonlinear couplings. These theoretically predicted mode structures have been compared in detail with the experimentally measured wave forms (using arrays of soft x-ray detectors). The agreement is excellent. More detailed comparisons between theory and experiment have required careful reconstructions of the ISX-B equilibria. The equilibria so constructed have permitted a precise evaluation of the ideal MHD stability properties of ISX-B. The present results indicate that the high ..beta.. ISX-B equilibria are marginally stable to finite eta ideal MHD modes. The resistive MHD calculations also show that at finite ..beta.. there are unstable resistive pressure driven modes.

• Research Organization: Oak Ridge National Lab., TN (USA); Texas Univ., Austin (USA). Inst. for Fusion Studies
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5333158
• Report Number(s): DOE/NBM-3017242; ON: DE83017242
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
COUPLING
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
ISX TOKAMAK
MAGNETOHYDRODYNAMICS
MECHANICS
NONLINEAR PROBLEMS
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
SPECTRA
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
X-RAY SPECTRA