Stabilization of collisional drift-tearing modes at the breakdown of the constant-. Psi. approximation

Journal Article · Sat Jun 01 04:00:00 EDT 1991 · Physics of Fluids B; (USA)

DOI:https://doi.org/10.1063/1.859828· OSTI ID:5793742

Migliuolo, S; Pegoraro, F; Porcelli, F ^[1]

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1. JET Joint Undertaking, Abingdon, Oxon OX14 3EA, England (GB)

The linear growth rate of the collisional drift-tearing mode is found to be a nonmonotonic function of the stability parameter {Delta}{prime}. It reaches a maximum for {Delta}{prime}{approx}0.5{Delta}{sup {prime}}{sub 1}={ital m}{omega}{sub A}/ {radical}{cflx {omega}}{sub *{ital e}}({cflx {omega}}{sub *{ital e}}{minus}{omega}{sub {ital di}}) {gt} 0, where {omega}{sub A}, {cflx {omega}}{sub *{ital e}}, {omega}{sub {ital di}} are the Alfven, electron drift wave, and ion diamagnetic frequencies, and becomes negative for {Delta}{prime} {ge} {Delta}{sup {prime}}{sub 1}, corresponding to the regime where the constant-{Psi} approximation breaks down. A second mode, identified as the diamagnetic modification of the {epsilon}{sup 1/3}{sub {eta}} mode near the condition for ideal magnetohydrodynamic (MHD) marginal stability, becomes unstable for {Delta}{prime}{ge}{Delta}{sup {prime}}{sub 2} = ({cflx {omega}}{sub *{ital e}}/{omega}{sub A}{epsilon}{sub {eta}}){sup 1/2} {gt} {Delta}{sup {prime}}{sub 1}, leaving a stable window in values of {Delta}{prime}. Applications to the stability of modes with poloidal and toroidal mode numbers {ital m} = {ital n} = 1 are presented.

• DOE Contract Number: AC02-78ET51013
• OSTI ID: 5793742
• Journal Information: Physics of Fluids B; (USA), Journal Name: Physics of Fluids B; (USA) Vol. 3:6; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700107 -- Fusion Energy-- Plasma Research-- Instabilities
700108* -- Fusion Energy-- Plasma Research-- Wave Phenomena
ALFVEN WAVES
COLLISIONAL PLASMA
CURRENTS
DIAMAGNETISM
DRIFT INSTABILITY
ELECTRIC CURRENTS
ELECTRON DRIFT
FLUID MECHANICS
HYDRODYNAMICS
HYDROMAGNETIC WAVES
INSTABILITY
INSTABILITY GROWTH RATES
ION WAVES
MAGNETISM
MAGNETOHYDRODYNAMICS
MECHANICS
MODIFICATIONS
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA MICROINSTABILITIES
PLASMA WAVES
STABILIZATION
TEARING INSTABILITY