Shock formation in a poloidally rotating tokamak plasma

Journal Article · Sat Feb 01 04:00:00 EST 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860290· OSTI ID:5068604

Shaing, K C ^[1]; Hazeltine, R D ^[2]; Sanuki, H ^[3]

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1. Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-8071 (United States)
2. Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712 (United States)
3. National Institute for Fusion Science, University of Nagoya, Nagoya (Japan)

When the Mach number {ital M}{sub {ital p}} of the poloidal rotation in a tokamak approaches unity, the poloidal variations of plasma density and potential appear to have the characteristics of a shock whose front lies on a plane (ribbon) of a fixed poloidal angle {eta}{sub 0}. The shock first appears, when 1{minus}{ital M}{sub {ital p}}{approx lt}({epsilon}){sup 1/2} ({epsilon} is the inverse aspect ratio), on the inside of the torus at a shock angle {eta}{sub 0}{ge}{pi} if the plasma rotates counterclockwise poloidally. As {ital M}{sub {ital p}} increases, {eta}{sub 0} moves in the direction of the poloidal rotation. At {ital M}{sub {ital p}}=1, {eta}{sub 0}=2{pi}. When {ital M}{sub {ital p}} {minus}1{approx lt}({epsilon}){sup 1/2}, the shock angle is at {eta}{sub 0}{approx lt}{pi}. The parallel viscosity associated with the shock is collisionality independent, in contrast to the conventional neoclassical viscosity. The viscosity reaches its maximum at {ital M}{sub {ital p}}=1, which is the barrier that must be overcome to have a poloidal supersonic flow. Strong up--down asymmetric components of poloidal variations of plasma density and potential develop at {ital M}{sub {ital p}} {congruent}1. In the edge region, the convective poloidal momentum transport weakens the parallel viscosity and facilitates the L--H transition.

• DOE Contract Number: AC05-84OR21400; FG05-80ET53088
• OSTI ID: 5068604
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:2; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
ASPECT RATIO
CLOSED PLASMA DEVICES
COMPRESSIBILITY
CONFINEMENT
FLUID FLOW
MACH NUMBER
MECHANICAL PROPERTIES
PLASMA
PLASMA CONFINEMENT
PLASMA DENSITY
ROTATING PLASMA
SHOCK WAVES
SUPERSONIC FLOW
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TRANSPORT THEORY
VELOCITY
VISCOSITY