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Spherical torus, compact fusion at low field

Description: A spherical torus is obtained by retaining only the indispensable components on the inboard side of a tokamak plasma, such as a cooled, normal conductor that carries current to produce a toroidal magnetic field. The resulting device features an exceptionally small aspect ratio (ranging from below 2 to about 1.3), a naturally elongated D-shaped plasma cross section, and ramp-up of the plasma current primarily by noninductive means. As a result of the favorable dependence of the tokamak plasma be… more
Date: February 1, 1985
Creator: Peng, Y. K. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Physics rationale for the engineering specifications for ZTH

Description: This report presents the physics rationale that established the engineering design of ZTH. The physics criteria are given and the implications regarding the engineering design are presented. Experimental and theoretical background evidence is given in support of the criteria but the justification is left to other reports and peer reviews. The physics criteria discussed here are limited to the ones deemed to be of highest engineering priority. 32 refs., 9 figs.
Date: January 1, 1987
Creator: Dimarco, J.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The effects of plasma deformability on the feedback stabilization of axisymmetric modes in tokamak plasmas

Description: The effects of plasma deformability on the feedback stabilization of axisymmetric modes of tokamak plasmas are studied. It is seen that plasmas with strongly shaped cross sections have unstable motion different from a rigid shift. Furthermore, the placement of passive conductors is shown to modify the non-rigid components of the eigenfunction in a way that reduces the stabilizing eddy currents in these conductors. Passive feedback results using several equilibria of varying shape are presented.… more
Date: January 1, 1992
Creator: Ward, D.J. (Centre de Recherches en Physique des Plasmas, Lausanne (Switzerland)) & Jardin, S.C. (Princeton Univ., NJ (United States). Plasma Physics Lab.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Post-stall wind tunnel data for NACA 44XX series airfoil sections

Description: Wind turbine blades operate over a wide angle of attach range. Unlike aircraft, a wind turbine's angle of attach range extends deep into stall where the three-dimensional performance characteristics of airfoils are not generally known. Peak power predictions upon which wind turbine components are sized depend on a good understanding of a blade's post-stall characteristics. The purpose of this wind tunnel study is to characterize the performance characteristics of a blade in stall as a… more
Date: January 1, 1985
Creator: Ostowari, C. & Naik, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modular Stellarator Fusion Reactor concept

Description: A preliminary conceptual study is made of the Modular Stellarator Reactor (MSR). A steady-state ignited, DT-fueled, magnetic fusion reactor is proposed for use as a central electric-power station. The MSR concept combines the physics of the classic stellarator confinement topology with an innovative, modular-coil design. Parametric tradeoff calculations are described, leading to the selection of an interim design point for a 4-GWt plant based on Alcator transport scaling and an average beta val… more
Date: August 1, 1981
Creator: Miller, R. L. & Krakowski, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Scoping and sensitivity analyses for the Demonstration Tokamak Hybrid Reactor (DTHR)

Description: The results of an extensive set of parametric studies are presented which provide analytical data of the effects of various tokamak parameters on the performance and cost of the DTHR (Demonstration Tokamak Hybrid Reactor). The studies were centered on a point design which is described in detail. Variations in the device size, neutron wall loading, and plasma aspect ratio are presented, and the effects on direct hardware costs, fissile fuel production (breeding), fusion power production, electri… more
Date: March 1, 1979
Creator: Sink, D. A. & Gibson, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha-particle losses in compact torsatron reactors

Description: Loss of alpha particles in compact torsatron reactors is studied. For 6, 9, and 12 field period reactors, the direct loss is a relatively weak function of radius and energy and varies from approx. =33% for M = 6 to approx. =18% for M = 12. Loss of alpha particles through scattering into the loss region is calculated using the Fokker-Plank equation for fast ions and found to contribute an additional alpha-particle energy loss of approx. =15%. The consequences of these relatively large losses for… more
Date: January 1, 1989
Creator: Painter, S.L. & Lyon, J.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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OCLATOR (One Coil Low Aspect Toroidal Reactor)

Description: A new approach to construct a tokamak-type reactor(s) is presented. Basically the return conductors of toroidal field coils are eliminated and the toroidal field coil is replaced by one single large coil, around which there will be placed several tokamaks or other toroidal devices. The elimination of return conductors should, in addition to other advantages, improve the accessibility and maintainability of the tokamaks and offer a possible alternative to the search for special materials to with… more
Date: February 1, 1980
Creator: Yoshikawa, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spherical torus (ST) concept and its reactor implications

Description: A brief description of the spherical torus design is given. The design concept includes resistive demountable toroidal field coils, poloidal divertor for impurity control, oscillating-field current maintenance, RF initiation and ramp-up of the plasma current, and flowing liquid-metal breeding blanket. 4 refs., 6 figs. (WRF)
Date: January 1, 1986
Creator: Peng, Y. K. M.; Lazarus, E. A.; Miller, R. L.; Carreras, B. A.; Hogan, J. T.; Krakowski, R. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ITER blanket and shield studies for high aspect ratio design option

Description: The attractiveness of the high aspect ratio design (HARD) option for ITER has motivated a study to assess the blanket and shield design performance for this configuration relative to the ITER reference design. The blanket and shield have been configured to take an advantage of the HARD option. The layered solid breeder blanket concept with water-coolant and steel-structure and the water-steel shield have been used. The changes in the neutron wall loading distribution, the mechanical design, the… more
Date: January 1, 1991
Creator: Gohar, Y.; Attaya, H.; Billone, M.; Johnson, C.; Kopasz, J.; Majumdar, S. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability of Local Modes in Low-Aspect-Ratio Stellarators

Description: The studies of MHD stability properties of stellarator-type configurations are complicated by the three-dimensional (3-D) nature of the equilibrium of these configurations. Usually, the unstable modes are pressure-driven and very localized around the rational surface. The 3-D Mercier stability criterion for local instabilities is therefore adequate for most of the stability studies. The method has been implemented in different 3-D equilibrium codes and is widely employed in stability calculatio… more
Date: January 1, 1989
Creator: Garcia, L.; Carreras, B. A. & Dominguez, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High n ballooning modes in highly elongated tokamaks

Description: An analytic study of stability against high n ballooning modes in highly elongated axisymmetric plasmas is presented and compared with computational results. From the equation for the marginal pressure gradient, it is found that the local shear plays an important role on the stability of elongated and shifted plasma, and that high elongation deteriorates the stability by decreasing the stabilizing effects of field line bending and local shear. The net contribution of the local shear to stabilit… more
Date: February 1, 1980
Creator: An, C.H. & Bateman, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Control of helium accumulation by fishbones

Description: It is well known that fishbone oscillations occur in the tokamak plasma at high {epsilon}{beta}p and in the presence of large hot trapped particle population. We adopt and extend the formalism of Chen et al. to analyze the trapped hot ion induced fishbones in the ITER-type plasma. Using the familiar assumptions like large assumptions like large aspect ratio and low beta, we considered the stability of the trapped-ion induced internal kink mode in the presence of alphas and one other species of … more
Date: January 1, 1989
Creator: Varadarajan, V. & Miley, G.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Results of Systems Studies for the STARFIRE Commercial Tokamak

Description: Extensive system and tradeoff studies were performed to support the selection process for the major parameters and design features of the STARFIRE commercial reactor. With a thermal power of 3800 MW, a neutron wall load of 3.5 MW/m/sup 2/ results in a relatively small-size reactor without imposing excessive requirements on the first-wall cooling capability, maximum toroidal-magnetic field, and frequency of structural material requirements. This moderately high-wall load requires that the first-… more
Date: January 1, 1979
Creator: Abdou, M. A.; Ehst, D. A. & Waganer, L. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability of n = 1 internal modes in tokamaks

Description: An extensive numerical study has been carried out for internal modes with toroidal mode number unity. These are internal kink modes, when the q = 1 surface falls within the plasma, and have a ballooning characteristic when q/sub axis/ > 1. Both modes show a dependence on the pressure and have a second region of stability at high ..beta... A parameter survey has been conducted, varying the geometry, i.e., aspect ratio, ellipticity, triangularity, etc. and the current profiles, through the pressu… more
Date: December 1, 1983
Creator: Manickam, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Horizontal axis wind turbine post stall airfoil characteristics synthesization

Description: Blade-element/momentum performance prediction codes are routinely used for wind turbine design and analysis. A weakness of these codes is their inability to consistently predict peak power upon which the machine structural design and cost are strongly dependent. The purpose of this study was to compare post-stall airfoil characteristics synthesization theory to a systematically acquired wind tunnel data set in which the effects of aspect ratio, airfoil thickness, and Reynolds number were invest… more
Date: June 1, 1991
Creator: Tangler, J.L. (Rockwell International Corp., Golden, CO (USA). Wind Energy Research Center) & Ostowari, C. (Texas A and M Univ., College Station, TX (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proceedings of US-Japan heliotron-stellarator workshop: Volume 3

Description: This paper is the third of four volumes on the US-Japan Heliotron-Stellarator Workshop. It contains talks on the following: Heliotron EICRF Heating Experiment; CHS Heating Systems (NBI, ECH, ICH); ICH Program for ATF; ICRF Wave Propagation; the HBQM Heliac Work; configuration studies; compact torsatron studies; low aspect ratio torsatron design; optimized small stellarator designs; configuration studies for ATF; currents in ATF; currents in ATF; computations of 3-D equilibria with islands; magn… more
Date: January 1, 1987
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The ARIES-I high-field-tokamak reactor: Design-point determination and parametric studies

Description: The multi-institutional ARIES study has examined the physics, technology, safety, and economic issues associated with the conceptual design of a tokamak magnetic-fusion reactor. The ARIES-I variant envisions a DT-fueled device based on advanced superconducting coil, blanket, and power-conversion technologies and a modest extrapolation of existing tokamak physics. A comprehensive systems and trade study has been conducted as an integral and ongoing part of the reactor assessment in order to iden… more
Date: January 1, 1989
Creator: Miller, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design of the ZTH vacuum liner

Description: The current status of the ZTH vacuum liner design is covered by this report. ZTH will be the first experiment to be installed in the CPRF (Confinement Physics Research Facility) at the Los Alamos National Laboratory and is scheduled to be operational at the rated current of 4 MA in 1992. The vacuum vessel has a 2.4 m major radius and a 40 cm minor radius. Operating parameters which drive the vacuum vessel mechanical design include a 300 C bakeout temperature, an armour support system capable of… more
Date: January 1, 1987
Creator: Prince, P.P. & Dike, R.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Features of spherical torus plasmas

Description: The spherical torus is a very small aspect ratio (A < 2) confinement concept obtained by retaining only the indispensable components inboard to the plasma torus. MHD equilibrium calculations show that spherical torus plasmas with safety factor q > 2 are characterized by high toroidal beta (..beta../sub t/ > 0.2), low poloidal beta (..beta../sub p/ < 0.3), naturally large elongation (kappa greater than or equal to 2), large plasma current with I/sub p//(aB/sub t0/) up to about 7 MA/mT, strong pa… more
Date: December 1, 1985
Creator: Peng, Y. K. M. & Strickler, D. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of toroidal multipoles to facilitate tokamak reactor studies

Description: A method of calculating the vacuum magnetic flux for plasma equilibrium over a range of aspect ratio A and major radius R is presented. Toroidal multipoles are used to fit the vacuum flux for a set of reference equilibria and the fitted moments are then used to parametrize the flux over the design space in A and R. An example is given in which the equilibrium flux for a D-shaped tokamak plasma is predicted and compared with the actual equilibrium code vacuum flux.
Date: May 1, 1984
Creator: Ehrhardt, A. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neoclassical transport in high [beta] tokamaks

Description: Neoclassical, transport in high [beta] large aspect ratio tokamaks is calculated. The variational method introduced by Rosenbluth, et al., is used to calculate the full Onsager matrix in the banana regime. These results are part of a continuing study of the high [beta] large aspect ratio equilibria introduced in Cowley, et al. All the neoclassical coefficients are reduced from their nominal low [beta] values by a factor ([var epsilon]/q[sup 2][beta])[sup [1/2]] II. This factor is the ratio of p… more
Date: December 1, 1992
Creator: Cowley, S.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cyclotron radiation losses in subcompact tori

Description: Subcompact tori such as the field reversed mirror (FRM) have a relatively large surface to volume ratio. This has raised concern that in advanced fuel devices cyclotron losses could prevent their viability as reactors. Indeed the cyclotron radiation produced is several times the fusion power. However, due to reabsorption in the FRM plasma, it turns out that less than 7% of the cyclotron radiation produced escapes the plasma. Then when reflection from the first wall is included, net losses are r… more
Date: January 1, 1980
Creator: Tetley, W. & Miley, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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