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Reactor Configuration Development for ARIES-CS

Description: New compact, quasi-axially symmetric stellarator configurations have been developed as part of the ARIES-CS reactor studies. These new configurations have good plasma confinement and transport properties, including low losses of α particles and good integrity of flux surfaces at high β. We summarize the recent progress by showcasing two attractive classes of configurations — configurations with judiciously chosen rotational transforms to avoid undesirable effects of low order resonances on the … more
Date: September 27, 2005
Creator: Ku LP, the ARIES-CS Team
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reducing Turbulent Transport in Toroidal Configurations via Shaping

Description: Recent progress in reducing turbulent transport in stellarators and tokamaks by 3D shaping using a stellarator optimization code in conjunction with a gyrokinetic code is presented. The original applications of the method focussed on ion temperature gradient transport in a quasi-axisymmetric stellarator design. Here, an examination of both other turbulence channels and other starting configurations is initiated. It is found that the designs evolved for transport from ion temperature gradient tu… more
Date: April 20, 2011
Creator: H.E. Mynick, N. Pomphrey and P. Xanthopoulos
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Results of Compact Stellarator Eengineering Trade Studies

Description: A number of technical requirements and performance criteria can drive stellarator costs, e.g., tight tolerances, accurate coil positioning, low aspect ratio (compactness), choice of assembly strategy, metrology, and complexity of the stellarator coil geometry. With the completion of a seven-year design and construction effort of the National Compact Stellarator Experiment (NCSX) it is useful to interject the NCSX experience along with the collective experiences of the NCSX stellarator community… more
Date: September 25, 2009
Creator: T. Brown, L. Bromberg, and M. Cole
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NCSX Construction Progress and Research Plans

Description: Stellarators use 3D plasma and magnetic field shaping to produce a steady-state disruption-free magnetic confinement configuration. Compact stellarators have additional attractive properties — quasi-symmetric magnetic fields and low aspect ratio. The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in partnership with the Oak Ridge National Laboratory (ORNL) to test the physics of a high-beta compact stellarator with a lowripp… more
Date: September 26, 2005
Creator: Neilson, G. H.; Heitzenroeder, P.; Lyon, J.; Nelson, B.; Reiersen, W.; Zarnstorff, M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ATFSR: a small torsatron reactor

Description: A small (average minor radius anti a approx. = 1 m), moderate-aspect-ratio torsatron reactor based on the Advanced Toroidal Facility (ATF) is proposed as a starting point for improved stellarator reactor designs. The major limitation of the compact size is the lack of space under the helical coils for the blanket and shield. Neoclassical confinement models for helically trapped particles show that a large electric potential (radial electric field) is necessary to achieve ignition in a device of… more
Date: January 1, 1985
Creator: Houlberg, W.A.; Lacatski, J.T. & Uckan, N.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Columbia Non-neutral Torus

Description: Final report for the Columbia Non-neutral Torus. This details the results from the design, construction and initial operation of the Columbia Non-neutral Torus.
Date: September 23, 2009
Creator: Pedersen, Thomas Sunn
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Global Alfven eigenmodes in WELDELSTEIN 7-AS

Description: In the presence of fast particle populations marginally stable global modes in the shear Alfven branch can be destabilized by wave particle resonances. This is particularly of concern in future large devices, where losses of resonant particles ({alpha}-particles in a reactor) may then limit the available heating power and also may cause damage of the first wall. In tokamaks TAE modes inside toroidicity induced gaps of the shear Alfven continua have been found. In stellarators with very weak she… more
Date: September 1, 1995
Creator: Weller, A.; Goerner, C. & Jaenicke, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of D pellet injection experiments in the W7-AS Stellarator

Description: A centrifugal injector was used to inject deuterium pellets (with 3--5 x 10{sup 19} atoms) at approx. equal 600 m/s into current-less, nearly shear-less plasmas in the Wendelstein 7-AS (W7-AS) stellarator. The D pellet was injected horizontally at a location where the non-circular and non-axisymmetric plasma cross section is nearly triangular. Visible-light TV pictures usually showed the pellet as a single ablating mass in the plasma, although the pellet occasionally broke in two or splintered … more
Date: July 1, 1997
Creator: Lyon, J. F.; Baylor, L. R.; Baldzuhn, J.; Fiedler, S.; Hirsch, M.; Kuehner, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Overview of the US stellarator reactor study

Description: This study, which uses a cost-minimization code that incorporates the ARIES costing and reactor component models with a I-D energy transport calculation, shows that a torsatron reactor could be competitive with a tokamak reactor.
Date: December 31, 1993
Creator: Lyon, J. F.; Gulec, K.; Miller, R. L. & El-Guebaly, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The U.S. Stellarator Power Plant Study

Description: The US Stellarator Power Plant Study (SPPS) was carried out by a national reactor study group that also conducts tokamak power plant studies (ARIES, PULSAR). The purpose was to assess the feasibility of a stellarator as a steady-state reactor and to identify critical issues for stellarator reactor design. The same system codes and assumptions (materials and costing approach) used in the tokamak reactor studies were used in this study of a 1-GW(e) stellarator power plant in order to develop a me… more
Date: July 1, 1995
Creator: Lyon, J.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NCSX Vacuum Vessel Fabrication

Description: The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The … more
Date: October 7, 2005
Creator: Viola, M. E.; Brown, T.; Heitzenroeder, P.; Malinowski, F.; Reiersen, W.; Sutton, L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of Scientific Simulation 3D Full Wave ICRF Code for Stellarators and Heating/CD Scenarios Development

Description: In this report we describe theory and 3D full wave code description for the wave excitation, propagation and absorption in 3-dimensional (3D) stellarator equilibrium high beta plasma in ion cyclotron frequency range (ICRF). This theory forms a basis for a 3D code creation, urgently needed for the ICRF heating scenarios development for the operated LHD, constructed W7-X, NCSX and projected CSX3 stellarators, as well for re evaluation of ICRF scenarios in operated tokamaks and in the ITER . The t… more
Date: August 15, 2005
Creator: V.L., Vdovin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assessment of stellarators as reactors

Description: Stellarators have significant operational advantages over tokamaks as ignited steady-state reactors: no dangerous disruptions, no need for continuous current drive and power recirculated to the plasma, less severe constraints on the plasma parameters and profiles, and access from the inboard side for easier maintenance. The US is starting a multi-year multi-institutional stellarator reactor study whose purpose is to ``identify and assess the feasibility of critical issues and their consequences… more
Date: July 1, 1993
Creator: Lyon, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On the Radial Structure of Fluctuations and Turbulence Induced Flows

Description: Comparative studies of the structure of turbulence have been carried out in stellarator plasmas with low (TJ-IU) and medium (L2-M) magnetic shear. In both devices, the value of the radial coherence of fluctuations is bursty. In the plasma edge region, the radial coherence is dominated by low frequency fluctuations ({lt}200 KHZ) in TJ-IU, whereas in L2-M, the radial coherence is due to high frequency fluctuations ({gt} 100 kHz). Numerical calculations of resistive ballooning turbulence show that… more
Date: January 1, 1997
Creator: Hidalgo, C.; Pedrosa, M. A.; Milligen, B. V /; Sanchez, R. B.; Garcia-Cortes, I.; Batanov, G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent progress in stellarator reactor conceptual design

Description: The Stellarator/Torsatron/Heliotron (S/T/H) class of toroidal magnetic fusion reactor designs continues to offer a distinct and in several ways superior approach to eventual commercial competitiveness. Although no major, integrated conceptual reactor design activity is presently underway, a number of international research efforts suggest avenues for the substantial improvement of the S/T/H reactor embodiment, which derive from recent experimental and theoretical progress and are responsive to … more
Date: January 1, 1985
Creator: Miller, R. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ideal low-n and Mercier mode stability boundaries for /ell/ = 2 torsatrons

Description: We studied the relationship between the stability properties of ideal low-n-internal modes and the three-dimensional (3-D) ideal Mercier criterion for /ell/ = 2 torsatron configurations. For the low-n stability studies, we used the stellarator expansion as implemented in the FAR code. The 3-D Mercier criterion was applied to equilibria calculated with the VMEC code. We found that low-n modes with singular surfaces lying in a Mercier region are, in general, unstable and the critical beta given b… more
Date: January 1, 1989
Creator: Dominguez, N.
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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Application of the stellarator expansion for plasma-stability studies in stellarators

Description: A numerical code, which utilizes the stellarator expansion, is developed and tested. It is used to investigate the magnetohydrodynamic stability properties of several stellarator configurations, including Heliotron E, Wendelstein VII-A, a modular-coil device, and ATF-1.
Date: April 1, 1983
Creator: Anania, G. & Johnson, J. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear phenomena, turbulence and anomalous transport in fusion plasmas

Description: The nonlinear nature of the plasma turbulence, as measured by bicoherence analysis, has been studied in stellarator (ATF and W7AS) and tokamak (PBXM) devices. In ATF, little nonlinear interaction is found in the scrape-off layer region whereas the strength of the coupling is enhanced in the edge plasma region where the level of fluctuations is consistent with the theoretical expectations from resistive interchange modes. In W7AS the level of bicoherence is significantly smaller than in ATF. The… more
Date: February 1, 1995
Creator: Hidalgo, C.; Estrada, T.; Sanchez, E.; Branas, B.; Garcia-Cortes, I.; Van Milligen, B. P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stellarator approach to fusion plasma confinement

Description: The stellarator is a toroidal fusion plasma confinement device with nested magnetic flux surfaces. The required twist of the field lines is produced by external helical coils rather than by plasma current, as in a tokamak. Stellarator devices are attractive fusion reactor candidates precisely because they offer the prospect of steady-state operation without plasma current. In the last few years the excellent results achieved with currentless stellarator plasmas of modest minor radius (10 to 20 … more
Date: January 1, 1985
Creator: Harris, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modular stellarator reactor conceptual design study

Description: A conceptual design study of the Modular Stellarator Reactor is summarized. The physics basis of the approach is elucidated with emphasis on magnetics performance optimization. Key engineering features of the fusion power core are described. Comparisons with an analogous continuous-helical-coil (torsatron) system are made as the basis of a technical and economic assessment.
Date: January 1, 1983
Creator: Miller, R. L.; Krakowski, R. A. & Bathke, C. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FIR interferometer and scattering measurements of ATF

Description: A 15-channel far-infrared (FIR) interferometer system has been constructed to measure the electron densities on the ATF plasmas. The system consists of a pair of cw 214-..mu..m difluoromethane (CH/sub 2/F/sub 2/) lasers, optically pumped by separate CO/sub 2/ lasers. The large number of channels is achieved by the use of reflective beam expansion optics to create a beam of 2 cm /times/ 45 cm. After passing through the plasma discharge, the elongated beam produced by the cylindrical mirrors is d… more
Date: January 1, 1989
Creator: Ma, C. H.; Hutchinson, D. P.; Fockedey, Y.; Vander Sluis, K. L. & Bennett, C. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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