Results 31 to 40 of about 73 (64)

Catastrophes in the ELMO Bumpy Torus

Physical Review Letters, 1982
The simple neoclassical nonresonant-point model of Hedrick et al. is slightly modified by leaving the ion transport unspecified (since it is now known to be resonant). Small continuous changes in the microwave power/neutral density can cause hysteresis and catastrophe jumps in the equilibria, in qualitative agreement with experiment.
George Vahala, Alkesh Punjabi, Edward G. Harris   +2 more
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ELMO Bumpy Torus with Enhanced Confinement

Physical Review Letters, 1983
A toroidal array of racetrack-shaped coils whose major axes are alternately oriented vertically and horizontally ("Andreoletti coils") provides neoclassical confinement that is strikingly superior to a simple bumpy torus of similar aspect ratio but circular coils.
R. L. Miller, R. A. Dandl, G. E. Guest
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Neoclassical Transportation in the ELMO Bumpy Torus

Physical Review Letters, 1978
In the ELMO bumpy torus, neoclassical transport coefficients depend critically on the ambipolar electric field. These coefficients, calculated for arbitrary radial electric fields, are applied in a one-dimensional radial-transport calculation which, for the first time, treats the electric field self-consistently.
E. F. Jaeger, D. A. Spong, C. L. Hedrick
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Plasma properties in the ELMO bumpy torus

Plasma Physics, 1983
Experiments with 200 kW of applied electron cyclotron heating (ECH) power have demonstrated electron temperatures of about 1 keV in the ELMO Bumpy Torus-Scale (EBT-S) device. Electron densities are in the range of (0.5-1.5)*1018 m-3 and increase as the square root of the applied ECH power. A potential well is present, and its depth in V closely follows
R J Colchin, T Uckan, F W Baity, L A Berry, F M Bieniosek, L Bighel, W A Davis, E Dullni, H O Eason, J C Glowienka, G A Hallock, G R Haste, D L Hillis, A Komori, T L Owens, R K Richards, L Solensten, T L White, J B Wilgen   +18 more
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Electron ring startup model for ELMO Bumpy Torus

The Physics of Fluids, 1984
The microwave power requirements for EBT electron ring startup are calculated based on the assumption that the ring electrons originate as runaways accelerated by the first harmonic resonance of the extraordinary mode. The calculated microwave power threshold for startup is consistent with the experimental data for the microwave power requirements ...
Hamasaki, S., Krall, N. A., Sperling, J. L.   +2 more
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Lower hybrid heating in ELMO Bumpy Torus

Nuclear Fusion, 1983
Absorption of lower hybrid wave energy by the electron and ion plasma components in the ELMO Bumpy Torus (EBT) is examined. The wave and plasma parameters used are those appropriate for the EBT-Scale (EBT-S) and EBT Proof-of-Principle (EBT-P) devices. The computations are carried out using a ray-tracing code that was developed at the Oak Ridge National
R.C. Goldfinger, A.H. Kritz, D.B. Batchelor   +2 more
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Transport studies of ECH-heated bumpy torus plasmas in the Elmo Bumpy Torus(EBT) and in the Nagoya Bumpy Torus(NBT)

Nuclear Fusion, 1984
A model of the measured potential profile for ECH-heated plasmas in EBT/NBT is used in the radial-transport equations for bumpy tori. The particle and energy confinement times are predicted along with the ECH power, the ion temperature and the neutral density necessary for a steady state to be maintained in these machines.
D.E. Hastings, T. Kamimura
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Modulational and filamentation instabilities in ELMO bumpy torus

Physica Scripta, 1991
An analytical investigation of modulational and filamentation instabilities of an upper-hybrid wave due to electron-acoustic density perturbations in a two-electron temperature plasma has been made. A hydrodynamical model of the plasma is used. Nonlinear dispersion relation and growth rates are calculated.
S Guha, Meenu Asthana, Ruby Sarkar
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Direct losses in the ELMO Bumpy Torus experiment

The Physics of Fluids, 1983
For resonant ions in the ELMO Bumpy Torus experiment (EBT), the width of the orbits near the resonance scales like (∂Ω/∂r)−1, where Ω is the precessional drift frequency. For (∂Ω/∂r)≊0 over most of the plasma, the ions will drift vertically out of the machine due to the toroidal magnetic field.
Hastings, D. E., Callen, J. D.
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Neoclassical transport in Elmo Bumpy Torus (EBT)

Nuclear Fusion, 1979
The calculation in this paper clarifies the ordering of transport regimes in Elmo Bumpy Torus (EBT), identified as one collisional and two collisionless regimes, plateau and banana. Explicit analytic estimates of the transport rates in the plateau regime are obtained.
R.D. Hazeltine, N.A. Krall, H.H. Klein, P.J. Catto   +3 more
openaire   +1 more source