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Managing EHS of PV-Related Equipment at the National Renewable Energy Laboratory: Preprint

Description: Managing environment, health, and safety (EHS) risks at a national laboratory, or university, can be intimidating to a researcher who is focused on research results. Laboratory research and development (R&D) operations are often driven by scientists with limited engineering support and lack well-refined equipment development resources. To add to the burden for a researcher, there is a plethora of codes, standards, and regulations that govern the safe installation and operation of photovolta… more
Date: June 1, 2012
Creator: McCuskey, T. & Nelson, B. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Demonstration of Tokamak Ohmic Flux Saving by Transient Coaxial Helicity Injection on NSTX

Description: Transient Coaxial Helicity Injection (CHI) started discharges in NSTX have attained peak currents up to 300 kA and when these discharges are coupled to induction, it has produced up to 200 kA additional current over inductive-only operation. CHI in NSTX has shown to be energetically quite efficient, producing a plasma current of about 10 A/Joule of capacitor bank energy. In addition, for the first time, the CHI produced toroidal current that couples to induction continues to increase with the e… more
Date: April 23, 2010
Creator: Raman, R.; Mueller, D.; Nelson, B. A.; Jarboe, T. R.; Gerhardt, S.; Kugel, H. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ramp-up of CHI Initiated Plasmas on NSTX

Description: Experiments on the National Spherical Torus (NSTX) have now demonstrated flux savings using transient coaxial helicity injection (CHI). In these discharges, the discharges initiated by CHI are ramped up with an inductive transformer and exhibit higher plasma current than discharges without the benefit of CHI initiation.
Date: October 29, 2009
Creator: Mueller, D.; Bell, R. E.; LeBlanc, B.; Roquemore, A. L.; Raman, R.; Jarboe, T. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Overview Of The ITER In-Vessel Coil Systems

Description: ELM mitigation is of particular importance in ITER in order to prevent rapid erosion or melting of the divertor surface, with the consequent risk of water leaks, increased plasma impurity content and disruptivity. Exploitable "natural" small or no ELM regimes might yet be found which extrapolate to ITER but this cannot be depended upon. Resonant Magnetic Perturbation has been added to pellet pacing as a tool for ITER to mitigate ELMs. Both are required, since neither method is fully d… more
Date: September 24, 2009
Creator: Heitzenroeder, P. J.; Chrzanowski, J. H.; Dahlgren, F.; Hawryluk, R. J.; Loesser, G. D.; Neumeyer, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solenoid-free Plasma Start-up in NSTX using Transient CHI

Description: Experiments in NSTX have now demonstrated the coupling of toroidal plasmas produced by the technique of Coaxial Helicity Injection (CHI) to inductive sustainment and ramp-up of the toroidal plasma current. In these discharges, the central Ohmic transformer was used to apply an inductive loop voltage to discharges with a toroidal current of about 100 kA created by CHI. The coupled discharges have ramped up to >700 kA and transitioned into an H-mode demonstrating compatibility of this startup … more
Date: January 5, 2009
Creator: Raman, R.; Jarboe, T.; Nelson, B.; Mueller, D. & Soukhanovskii, V. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Solenoid-free Plasma Start-up in NSTX using Transient CHI

Description: Experiments in NSTX have now unambiguously demonstrated the coupling of toroidal plasmas produced by the technique of CHI to inductive sustainment and ramp-up of the toroidal plasma current. This is an important step because an alternate method for plasma startup is essential for developing a fusion reactor based on the spherical torus concept. Elimination of the central solenoid would also allow greater flexibility in the choice of the aspect ratio in tokamak designs now being considered. The … more
Date: November 3, 2008
Creator: Raman, R.; Nelson, B. A.; Mueller, D.; Jarboe, T. R.; Bell, M. G.; LeBlanc, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Solenoid-free Plasma Start-up in NSTX using Transient CHI

Description: Experiments in NSTX have now unambiguously demonstrated the coupling of toroidal plasmas produced by the technique of CHI to inductive sustainment and ramp-up of the toroidal plasma current. This is an important step because an alternate method for plasma startup is essential for developing a fusion reactor based on the spherical torus concept. Elimination of the central solenoid would also allow greater flexibility in the choice of the aspect ratio in tokamak designs now being considered. The … more
Date: November 3, 2008
Creator: Raman, R.; Nelson, B. A.; Mueller, D.; Jarboe, T. R.; Bell, M. G.; LeBlanc, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Potential of Photovoltaics

Description: Presented at the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL) Fall Technical Conference 2008 and 22nd International Vacuum Web Coating Conference held October 19-22, 2008 in Myrtle Beach, South Carolina. This presentation discusses PV in the world energy portfolio, PV basics, PV technologies, and vacuum web-coating applications in PV.
Date: October 22, 2008
Creator: Nelson, B. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Engineering Accomplishments in the Construction of NCSX

Description: The National Compact Stellarator Experiment (NCSX) was designed to test a compact, quasiaxisymmetric stellarator configuration. Flexibility and accurate realization of its complex 3D geometry were key requirements affecting the design and construction. While the project was terminated before completing construction, there were significant engineering accomplishments in design, fabrication, and assembly. The design of the stellarator core device was completed. All of the modular coils, toroidal … more
Date: September 1, 2008
Creator: Neilson, G. H.; Heitzenroeder, P. J.; Nelson, B. E.; Reiersen, W. T.; Brooks, A.; Brown, T. G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Process Development and Integration Lab (PDIL) + Measurements and Characterization

Description: The Process Development and Integration Lab (PDIL) Vision is to integrate deposition, characterization, and processing by being flexible and robust; having a standardized transfer interface; and controlled sample ambient between tools. The benefits are: (1) answers to previously inaccessible research questions; (2) control and characterization of critical surfaces (interfaces) and how their impact on subsequent layers; (3) assess process-related source chemistry, surface chemistry and kinetics,… more
Date: April 1, 2008
Creator: Nelson, B.
Item Type: Refine your search to only Presentation
Partner: UNT Libraries Government Documents Department
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Design, Installation and Performance of the New insulator for NSTX CHI Experiments

Description: Coaxial Helicity Injection (CHI), a non-inductive method to initiate plasma and generate toroidal plasma current, is being investigated in the National Spherical Torus Experiment (NSTX). The center stack and outer vacuum vessel are separated by insulating gaps at the top and bottom of the slim central column so that a high voltage (up to 2 kV) can be applied between them from a pulsed power supply or a capacitor bank to initiate an arc discharge. In the presence of a suitable poloidal magnetic … more
Date: March 5, 2008
Creator: Mueller, D.; Chrzanowski, J.; Gates, D.; Menard, J.; Raman, R.; Jarboe, T. R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Non-inductive Solenoid-less Plasma Current Start-up in NSTX Using Transient CHI

Description: Coaxial Helicity Injection (CHI) has been successfully used in the National Spherical Torus Experiment (NSTX) for a demonstration of closed flux current generation without the use of the central solenoid. The favorable properties of the Spherical Torus (ST) arise from its very small aspect ratio. However, small aspect ratio devices have very restricted space for a substantial central solenoid. Thus methods for initiating the plasma current without relying on induction from a central solenoid ar… more
Date: May 23, 2007
Creator: Raman, R.; Jarboe, T. R.; Nelson, B. A.; Bell, M. G.; Ono, M.; Bigelow, T. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Integrating Deposition, Processing, and Characterization Equipment within the National Center for Photovoltaics

Description: The purpose of the process integration project of the National Center for Photovoltaics (NCPV) is to develop an infrastructure that will allow researchers to gain new knowledge that is difficult--if not impossible--to obtain with existing equipment. This difficulty is due, in part, to the state of our existing tool set, which lacks sufficient in-situ or real-time measurement capabilities, or lacks access to analytical tools where the sample remains in a controlled environment between deposition… more
Date: November 1, 2005
Creator: Nelson, B.; Robbins, S. & Sheldon, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Production Phase for the National Compact Stellarator Experiment (NCSX) Modular Coil Winding Forms

Description: The production phase for the NCSX modular coil winding forms has been underway for approximately one year as of this date. This is the culmination of R&D efforts performed in 2001-4. The R&D efforts included limited manufacturing studies while NCSX was in its conceptual design phase followed by more detailed manufacturing studies by two teams which included the fabrication of full scale prototypes. This provided the foundation necessary for the production parts to be produced under a fi… more
Date: October 20, 2005
Creator: Heitzenroeder, P.; Brown, T.; Neilson, G.; Malinowski, F.; Sutton, L.; Nelson, B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Progress In NCSX and QPS Design and Construction

Description: 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). The stellarator core is designed to produce a compact 3-D plasma that combines stellarator and tokamak physics advantages. The engineering challenges of NCSX stem from its complex geometry. From the project's start in April, 2003 to September, 2004, the fabrication specifications for the project's two lo… more
Date: October 20, 2005
Creator: Reiersen, W.; Heitzenroeder, P.; Neilson, G. H.; Nelson, B.; Zarnstorff, M.; Brown, T. et al.
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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Manufacturing Development of the NCSX Modular Coil Windings

Description: The modular coils on the National Compact Stellarator Experiment (NCSX) present a number of significant engineering challenges due to their complex shapes, requirements for high dimensional accuracy and the high current density required in the modular coils due to space constraints. In order to address these challenges, an R&D program was established to develop the conductor, insulation scheme, manufacturing techniques, and procedures. A prototype winding named Twisted Racetrack Coil (TRC) was … more
Date: September 27, 2005
Creator: Chrzanowski JH, Fogarty PJ, Heitzenroeder PJ, Meighan T, Nelson B, Raftopoulos S, Williamson D
Item Type: Refine your search to only Report
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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The ZaP Flow Z-Pinch Project

Description: The results from the ZaP experiment are consistent with the theoretical predictions of sheared flow stabilization. Z pinches with a sheared flow are generated in the ZaP experiment using a coaxial accelerator coupled to an assembly region. The current sheet in the accelerator initially acts as a snowplow. As the Z pinch forms, plasma formation in the accelerator transits to a deflagration process. The plasma exits the accelerator and maintains the flow in the Z pinch. During the quiescent perio… more
Date: September 1, 2005
Creator: Shumlak, U. & Nelson, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Status and Plans for the National Spherical Torus Experimental Research Facility

Description: An overview of the research capabilities and the future plans on the MA-class National Spherical Torus Experiment (NSTX) at Princeton is presented. NSTX research is exploring the scientific benefits of modifying the field line structure from that in more conventional aspect ratio devices, such as the tokamak. The relevant scientific issues pursued on NSTX include energy confinement, MHD stability at high beta, non-inductive sustainment, solenoid-free start-up, and power and particle handling. I… more
Date: July 27, 2005
Creator: Columbia University
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Observation of Persistent Edge Current Driven by Coaxial Helicity Injection (CHI)

Description: Coaxial Helicity Injection, CHI, has been used on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40 (2000) 557], the Helicity Injected Torus (HIT) [B.A. Nelson et al., Phys. Rev. Lett. 72 (1994) 3666] and HIT-II [T.R. Jarboe et al., Phys. Plasmas 5 (1998) 1807] to initiate plasma and to drive up to 400 kA of toroidal current. On HIT-II, CHI initiated discharges have been successfully coupled to ohmic sustainment [R. Raman et al., Phys. Plasmas 11 (2004) 2565]. This … more
Date: April 21, 2005
Creator: Mueller, D.; Nelson, B. A.; Hamp, W. T.; Redd, A. J.; Jarboe, T. R.; O'Neill, R. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NCPV Process Integration Project: Purpose, Status and Direction

Description: The primary purpose of the process integration project of the National Center for Photovoltaics (NCPV) is to develop an infrastructure that will allow researchers to gain new knowledge that is difficult-if not impossible-to obtain with existing equipment. This difficulty is due, in part, to the state of our existing tool set, which lacks sufficient in-situ or real-time measurement capabilities, or lacks access to analytical tools where the sample remains in a controlled environment between depo… more
Date: February 1, 2005
Creator: Nelson, B.; Robbins, S. & Sheldon, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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