Effect of energetic particles on stability of mirror and tokamak plasmas

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6685330

Stotler, D P

Effects of an energetic particle species on high-mode-number, curvature-driven instabilities in magnetic mirror and tokamak plasmas are studied. The author investigates whether or not these hot particles can stabilize the magnetohydrodynamic (MHD) ballooning mode by having magnetic drift velocities large enough that they do not respond on the usual time scale of the instability and consequently allow thermonuclear fusion devices to operate at higher, more efficient plasma pressures. However, the energetic particles themselves are subject to instabilities that limit the effectiveness of this procedure. Using an MHD particle simulation code, the stabilizing effect of a diamagnetic well formed by the energetic particles is demonstrated in an axisymmetric mirror by treating the hot species as a rigid current ring. The results match those predicted by an analytic theory based on the MHD equations. More general aspects of linear stability in mirrors containing energetic particles are examined through analysis of equations derived from the drift kinetic equation. Numerical techniques are used to show that a magnetic compressional instability can arise if the core plasma density is to high or if the hot particle pressure gradient is too large. A similar set of equations is solved numerically in a tokamak geometry to determine whether or not energetic particles will allow access to the desirable second stability region for MHD ballooning modes.

• Research Organization: Texas Univ., Austin (USA)
• OSTI ID: 6685330
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107* -- Fusion Energy-- Plasma Research-- Instabilities
BALLOONING INSTABILITY
CLOSED PLASMA DEVICES
FLUID MECHANICS
HYDRODYNAMICS
INSTABILITY
MAGNETIC MIRRORS
MAGNETOHYDRODYNAMICS
MECHANICS
OPEN PLASMA DEVICES
PARTICLE KINEMATICS
PLASMA
PLASMA DRIFT
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
SIMULATION
STABILITY
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
VELOCITY