Shock formation in a poloidally rotating tokamak plasma

Technical Report · Sat Jun 01 04:00:00 EDT 1991

OSTI ID:5372476

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

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1. Oak Ridge National Lab., TN (United States)
2. Texas Univ., Austin, TX (United States). Inst. for Fusion Studies
3. National Inst. for Fusion Science, Nagoya (Japan)

When the Mach number M{sub 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} Mp {approx lt} {radical}{bar {epsilon}} ({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 M{sub p} increases, {eta}{sub 0} moves in the direction of the poloidal rotation. At M{sub p} = 1, {eta}{sub 0} = 2{pi}. When M{sub p} {minus} {approx lt} {radical}{bar {epsilon}}, 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 M{sub 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 M{sub p} {approx equal} 1. In the edge region, the convective poloidal momentum transport weakens the parallel viscosity and facilitates the transition from L-mode to H-mode. 24 refs., 2 figs.

• Research Organization: Texas Univ., Austin, TX (United States). Inst. for Fusion Studies; Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG05-80ET53088; AC05-84OR21400
• OSTI ID: 5372476
• Report Number(s): DOE/ET/53088-505; IFSR--505; ON: DE91018417
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101 -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
700103* -- Fusion Energy-- Plasma Research-- Kinetics
ANGULAR MOMENTUM
CLOSED PLASMA DEVICES
CONFINEMENT
FLUID FLOW
H-MODE PLASMA CONFINEMENT
MAGNETIC FIELDS
MOMENTUM TRANSFER
PLASMA
PLASMA CONFINEMENT
PLASMA DENSITY
ROTATING PLASMA
SHOCK WAVES
SUPERSONIC FLOW
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
VISCOSITY