Study of turbulent heating effects in the high beta tokamak Torus II

Journal Article · Wed Oct 01 04:00:00 EDT 1980 · Phys. Fluids; (United States)

DOI:https://doi.org/10.1063/1.862896· OSTI ID:6895071

Georgiou, G E; Marshall, T C; Weber, P G

Torus II is a rectangular cross section, high beta tokamak which has a glass vacuum vessel (aspect ratio of 3.5) filled with 12 mTorr helium. The plasma is heated by turbulent poloidal skin currents, induced by a fast (tau/sub r/=1.7 ..mu..sec) reversal of the toroidal field which converts a toroidal Z pinch plasma into a tokamak plasma. By using the broadening of He II 4686 A and impurity lines, it is found that strong turbulence (E< or =30 kV/cm microscopic fields at frequency < or =..omega../sub p/iapprox. =3 x 10/sup 10/ rad/sec) is induced during the heating phase. The turbulent E fields maximize in the region of maximum induced poloidal skin current (..cap alpha..partialB/sub phi//partialr). The resulting high beta tokamak plasma, with <..beta..>/sub v/approx. =10% and n/sub e/approx. =10/sup 15/ cm/sup -3/, has an initially peaked radial temperature profile with T/sub i/approx. =180 eV at the plasma center. A few microseconds later, the He II-determined ion temperature becomes nearly spatially flat at T/sub i/approx. =75 eV, and then decreases slowly in time. Impurity ion lines indicated a temperature approximately 100 eV greater than He II. All line profiles indicated a poloidal circulation with E/sub r/ x B/sub phi/ characteristics and E/sub r/approx. =100 V/cm radially inward. The spectroscopy was done in the visible region using a six channel polychrometer having a 0.2 A resolution, which is capable of radial scans of the plasma. The details of turbulent heating derived from the analysis of ion line profiles are presented.

• Research Organization: Plasma Laboratory, Columbia University, New York, New York 10027
• DOE Contract Number: EY-76-S-02-2456
• OSTI ID: 6895071
• Journal Information: Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 23:10; ISSN PFLDA
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
&amp; Production
CLOSED PLASMA DEVICES
ELECTRIC FIELDS
EVEN-EVEN NUCLEI
FLUCTUATIONS
FLUIDS
HEATING
HELIUM 4
HELIUM II
HELIUM ISOTOPES
HIGH-BETA PLASMA
INSTABILITY
ION ACOUSTIC WAVES
ION TEMPERATURE
ION WAVES
ISOTOPES
LIGHT NUCLEI
LINE BROADENING
NUCLEI
PLASMA
PLASMA DIAGNOSTICS
PLASMA HEATING
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
PLASMA WAVES
QUANTUM FLUIDS
SPECTROSCOPY
STABLE ISOTOPES
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TORUS-II TOKAMAK
TURBULENCE
TURBULENT HEATING
VARIATIONS