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Physics of burn control in tokamak reactors

Description: A one-dimensional multifluid transport code was used to investigate some of the critical physics considerations for long burn times in a tokamak fusion reactor. Among these are the effects of helium ash build-up, toroidal field ripple, and fueling in the presence of a divertor. Particle and energy transport models are based on extrapolations from present day devices.
Date: January 1, 1979
Creator: Attenberger, S.E. & Houlberg, W.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proposed magnet system for EBT-P

Description: Since EBT-P, and other EBT devices, depends on having closed field lines for its successful operation, a very tight tolerance (on the order of 6 parts in 10/sup 4/) must be imposed on certain components of the field error. This is a global tolerance that influences the design of each magnet, its leads, the electrical bus, and the relative position of each magnet to its neighbors. This paper discusses the design, and field error analysis of the ORNL reference design for EBT-P.
Date: January 1, 1979
Creator: Ballou, J. K.; McManany, T. J.; Power, W. H. & Yeh, H. T.
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Partner: UNT Libraries Government Documents Department
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Lower hybrid heating associated with mode conversion on the Wisconsin octupole

Description: This thesis addresses the following key issues in the lower hybrid frequency range: 1. What are the importent physics aspects of wave propagation and heating in an experimental situation. 2. How effective is plasma heating in the complex magnetic field configuration of the octupole. Experimental work is accomplished by launching 1-10ms pulses of up to 40kW of radio frequency power at 140MHz corresponding to the hot plasma lower hybrid resonance in the octupole. A diploe antenna which is moveabl… more
Date: August 1, 1979
Creator: Owens, T. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design and fabrication of a large rectangular magnetic cusp plasma source for high intensity neutral beam injectors

Description: The design and fabrication techniques for a large, rectangular magnetic bucket plasma source are described. This source is compatible with the accelerator structures for the TFTR and DIII neutral-beam systems.
Date: November 1, 1979
Creator: Biagi, L. A.; Berkner, K. H.; Ehlers, K. W.; Paterson, J. A. & Porter, J. R.
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Partner: UNT Libraries Government Documents Department
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Successor oscillations of internal disruptive instabilities in the PLT tokamak

Description: The experimentally observed persistence of the m = 1 mode following an internal disruption is described. The hot central region appears to spiral outward, being pared by interception with the radius of q = 1 (as deduced from the radial extend of the m = 1 mode). The outward motion of the axis can be arrested and the surviving helical filament can subsequently spiral inward, rather than being annihilated as expected from nonlinear resistive internal kink mode simulations.
Date: June 1, 1979
Creator: Sauthoff, N. R.; Von Goeler, S.; Eames, D. R. & Stodiek, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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INGEN: a general-purpose mesh generator for finite element codes

Description: INGEN is a general-purpose mesh generator for two- and three-dimensional finite element codes. The basic parts of the code are surface and three-dimensional region generators that use linear-blending interpolation formulas. These generators are based on an i, j, k index scheme that is used to number nodal points, construct elements, and develop displacement and traction boundary conditions. This code can generate truss elements (2 modal points); plane stress, plane strain, and axisymmetry two-d… more
Date: May 1, 1979
Creator: Cook, W.A.
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Partner: UNT Libraries Government Documents Department
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Particle diffusion by magnetic perturbations of axisymmetric geometries

Description: The quasilinear theory of collisionless test particle diffusion in stochastic magnetic fields is extended to include the effects of finite gyroradius, particle drifts, and magnetic trapping. Runaway confinement is substantially improved relative to earlier estimates which assumed that particles exactly followed field lines. Trapped particles are not expected to be stochastic.
Date: August 1, 1979
Creator: Mynick, H.E. & Krommes, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Absolute dissipative drift-wave instabilities in tokamaks

Description: Contrary to previous theoretical predictions, it is shown that the dissipative drift-wave instabilities are absolute in tokamak plasmas. The existence of unstable eigenmodes is shown to be associated with a new eigenmode branch induced by the finite toroidal couplings.
Date: July 1, 1979
Creator: Chen, L.; Chance, M. S. & Cheng, C. Z.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Time varying eddy currents on a conducting surface in 3-D using a network mesh method

Description: The method presented in this paper was developed for the purpose of analyzing the eddy currents in the TFTR vacuum vessel. The basic principle in this method lies in representing a conducting surface as a network comprised of a number of branches. Each branch has a resistance and a self-inductance as well as mutuals to all other branches. The resulting branch resistance and branch inductance matrices are transformed into mesh matrices by a conventional network procedure. By using these mesh mat… more
Date: April 1, 1979
Creator: Christensen, U.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influence of globalmagnetic perturbations on plasma behavior in Elmo Bumpy Torus

Description: The sensitivity of plasma confinement to magnetic field error effects has been tested experimentally using externally introduced global field errors on the ELMO Bumpy Torus (EBT). Below a critical error field (deltaB/sub r//B)/sub cr/ of approx. = to 0.6-1 x 10/sup -3/ the plasma was observed to be essentially free from convective cells, toroidal currents, and instabilities. This observed critical value is comparable to a neoclassical critical field error (deltaB/sub r//B)/sub cr/ approx. = rho… more
Date: February 1, 1979
Creator: Quon, B.H.; Dandl, R.A.; Colestock, P.L.; :Bieniosek, F.M. & Ikegami, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of the rf quadrupole in linear accelerators for heavy ion fusion

Description: The rf quadrupole (RFQ) linac structure is proposed as an alternative to a system composed of a buncher and independently phased cavities in the low-velocity acceleration section. Beam dynamics simulation studies have demonstrated that with the RFQ (1) high transmission and low beam loss are possible, (2) it is possible to use a low voltage 0.25 MV dc injector and still obtain high output beam currents, (3) the current required from the injector is reduced because of the high transmission of th… more
Date: January 1, 1979
Creator: Wangler, T. P. & Stokes, R. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Numerical Study of the Initial Dynamics in Tormac

Description: Using a single fluid magnetohydrodynamic (MHD) code, we study the initial plasma dynamics in Tormac, an experimental device which attempts to confine plasma in a toroidal, two-pole cusp field. The code is in two dimensions and includes classical electrical conductivity and a constant heat conductivity. The full set of nonlinear MHD equations for the mass density, fluid velocity, temperature, the poloidal flux function, and the poloidal current function are solved using a predictor-corrector met… more
Date: January 1, 1979
Creator: Aydemir, A. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status of ISABELLE lattice

Description: ISABELLE, a facility for colliding protons with center of mass energies between 60 and 800 GeV, is presently under construction at Brookhaven National Laboratory. The device consists of two identical rings for the accumulation, acceleration and storage of proton beams, shaped and interlaced in the horizontal plane to intersect in six so-called crossing points where the beams that rotate in opposite directions in the two rings are exposed to each other. The overall dimensions of the facility are… more
Date: January 1, 1979
Creator: Claus, J.; Cornacchia, M.; Courant, E. D. & Parzen, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bundle divertor for INTOR

Description: Studies undertaken for INTOR indicate that for a remotely handled, ignited tokamak both conventional poloidal divertors as (PDX, Phase 1) and bundle divertors (ISX-B, Phase 1) will require improvement. Work has been underway for more than a year at ORNL in collaboration with Westinghouse on improving the bundle divertor concept. This report summarizes the work to date.
Date: September 1, 1979
Creator: Sheffield, J. (comp.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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RF quadrupole beam dynamics design studies

Description: The radio-frequency quadrupole (RFQ) linear accelerator structure is expected to permit considerable flexibility in achieving linac design objectives at low velocities. Calculational studies show that the RFQ can accept a high-current, low-velocity, dc beam, bunch it with high efficiency, and accelerate it to a velocity suitable for injection into a drift-tube linac. Although it is relatively easy to generate a satisfactory design for an RFQ linac for low beam currents, the space-charge effects… more
Date: January 1, 1979
Creator: Crandall, K. R.; Stokes, R. H. & Wangler, T. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Voltage breakdown testing for the radio-frequency quadrupole accelerator

Description: Designs of radio-frequency quadrupole (RFQ) accelerators with reasonable length require operation with surface fields above the limit imposed by Kilpatrick's Criterion. A cavity was designed using SUPERFISH to test the validity of this Criterion and to determine operating limits for the RFQ. The experimental setup and procedure are described, as are the data and results. A method of calibrating the test is presented.
Date: January 1, 1979
Creator: Williams, S. W.; Rodenz, G. W.; Humphry, F. J. & Potter, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanical design considerations in FMIT RFQ development

Description: The mechanical features of the several rf structures that have been made to test the theory of the radio-frequency quadrupole (RFQ) are briefly described. A 425-MHz structure, designed as a proof-of-principle (POP) test, is described in detail. Methods of coupling rf power into the structure, temperature control, tuning, and mode separation are discussed. The methods and setup of N/C machinery used to generate the critical geometry surrounding the RFQ aperture are detailed fully. Finally, the a… more
Date: January 1, 1979
Creator: Fuller, C. W.; Williams, S. W. & Potter, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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MEQALAC: a new approach to low beta acceleration

Description: An acceleration system is described which allows one to accelerate high currents of ions at very low velocities. The main principle is to utilize an array of electrostatic quadrupoles in an rf linac drift tube, rather than a single magnetic quadrupole, as is usually the case. Because electrostatic quads can be built with very small apertures, relatively high frequencies can be used. A number of examples are given.
Date: June 1, 1979
Creator: Maschke, A.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Linear and non-linear calculation of resistive magnetohydrodynamic instabilities

Description: The time-dependent, linear and non-linear, resistive magnetohydrodynamic, numerical models that have been developed at MFECC are reviewed. The purpose of these codes is to compute growth rates, mode structure and saturation of tearing, rippling, and interchange modes in fusion experiments. Cartesian, cylindrical, helical, and toroidal geometries are used in the applications. The numerical methods are described and applications to reversed field configurations are presented.
Date: September 1, 1979
Creator: Killeen, J.; Schnack, D.D. & Shestakov, A.I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Strong plasma acceleration by slow shocks resulting from magnetic reconnection

Description: An externally-driven magnetic reconnection is simulated for two two-dimensional magnetohydrodynamic models with anomalous resistivity: a closed boundary model where an O-type neutral point is formed between two X-type neutral points; and an open-ended model where only an X-type neutral point is formed. Computer runs have shown that: (1) X-shaped (Petschek type) slow shocks are formed. (2) In the closed boundary case, the plasma entering into the magnetic island through the X-type neutral points… more
Date: July 1, 1979
Creator: Sato, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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2 meg-ampere prototype levitated coil for multipole fusion

Description: The coils major diameter is 1.0 meter and it occupies a cross-section which is about 0.2 meter minor in diameter. The prototype coil will carry four times the current of the largest such magnet built to date. As a result, the peak induction in the coil is about 8 T and the stored magnetic energy will be around 3 MJ. The paper describes the proposed Nb/sub 3/SN superconductor, the quench protection system which is based on the LBL shorted secondary concept, the isochroic refrigeration storage sy… more
Date: November 1, 1979
Creator: Green, M. A. & Glueck, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of the ISX-B experimental program

Description: The ISX-B tokamak is a modestly sized device that is designed to explore questions closely related to the design of future tokamak devices, such as the Engineering Test Facility (ETF). The major program emphasis is on high-..beta.. plasma operation using neutral beams to heat plasmas with noncircular cross sections. In addition, substantial efforts are under way or planned in the areas of plasma-wall interactions, coated limiter studies, electron-cyclotron heating, ripple injection, impurity fl… more
Date: January 1, 1979
Creator: Saltmarsh, M.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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