Download or read book Visible Imaging of Edge Turbulence in NSTX written by S. J. Zweben and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Visible Imaging of Edge Turbulence in NSTX written by S. J. Zweben and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Speed Imaging of Edge Turbulence in NSTX written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The two-dimensional radial versus poloidal structure and motion of edge turbulence in NSTX (National Spherical Torus Experiment) were measured by using high-speed imaging of the visible light emission from a localized neutral gas puff. Edge turbulence images are shown and analyzed for Ohmic, L-mode (low-confinement mode) and H-mode (high-confinement mode) plasma conditions. Typical edge turbulence poloidal correlation lengths as measured using this technique are = 4 ± 1 cm and autocorrelation times are 40 ± 20 [mu]sec in all three regimes. The relative fluctuation level is typically smaller in H-mode than in L-mode, and transitions from H- to L-mode and can occur remarkably quickly (=30 [mu]sec). The two-dimensional images often show localized regions of strong light emission which move both poloidally and radially through the observed region at a typical speed of =105 cm/sec, and sometimes show spatially coherent modes.
Download or read book High Speed Imaging of Edge Turbulence in NSTX written by S. J. Zweben and published by . This book was released on 2003 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Edge Turbulence Imaging on NSTX and Alcator C mod written by S. J. Zweben and published by . This book was released on 2002 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Edge Turbulence Imaging on NSTX and Alcator C mod written by S. J. Zweben and published by . This book was released on 2002 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Images of Edge Turbulence in NSTX written by S. J. Zweben and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Images of Edge Turbulence in NSTX written by S. J. Zweben and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tangential 2 D Edge Imaging for GPI and Edge Impurity Modeling written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nova Photonics, Inc. has a collaborative effort at the National Spherical Torus Experiment (NSTX). This collaboration, based on fast imaging of visible phenomena, has provided key insights on edge turbulence, intermittency, and edge phenomena such as edge localized modes (ELMs) and multi-faceted axisymmetric radiation from the edge (MARFE). Studies have been performed in all these areas. The edge turbulence/intermittency studies make use of the Gas Puff Imaging diagnostic developed by the Principal Investigator (Ricardo Maqueda) together with colleagues from PPPL. This effort is part of the International Tokamak Physics Activity (ITPA) edge, scrape-off layer and divertor group joint activity (DSOL-15: Inter-machine comparison of blob characteristics). The edge turbulence/blob study has been extended from the current location near the midplane of the device to the lower divertor region of NSTX. The goal of this effort was to study turbulence born blobs in the vicinity of the X-point region and their circuit closure on divertor sheaths or high density regions in the divertor. In the area of ELMs and MARFEs we have studied and characterized the mode structure and evolution of the ELM types observed in NSTX, as well as the study of the observed interaction between MARFEs and ELMs. This interaction could have substantial implications for future devices where radiative divertor regions are required to maintain detachment from the divertor plasma facing components.
Download or read book Magnetic Fusion Energy written by George Neilson and published by Woodhead Publishing. This book was released on 2016-06-02 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Fusion Energy: From Experiments to Power Plants is a timely exploration of the field, giving readers an understanding of the experiments that brought us to the threshold of the ITER era, as well as the physics and technology research needed to take us beyond ITER to commercial fusion power plants. With the start of ITER construction, the world’s magnetic fusion energy (MFE) enterprise has begun a new era. The ITER scientific and technical (S&T) basis is the result of research on many fusion plasma physics experiments over a period of decades. Besides ITER, the scope of fusion research must be broadened to create the S&T basis for practical fusion power plants, systems that will continuously convert the energy released from a burning plasma to usable electricity, operating for years with only occasional interruptions for scheduled maintenance. Provides researchers in academia and industry with an authoritative overview of the significant fusion energy experiments Considers the pathway towards future development of magnetic fusion energy power plants Contains experts contributions from editors and others who are well known in the field
Download or read book Observations of the Turbulence in the Scrape off layers of Alcator C Mod and NSTX and Comparisons with Simualtion sic written by James L. Terry and published by . This book was released on 2002 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The intermittent turbulent transport in the scrape-off-layer of Alcator C-Mod and NSTX is studied experimentally by imaging with a very high density of spatial measurements. The 2-D structure and dynamics of emission from a localized gas puff are observed, and intermittent features (also sometimes called "filaments" or "blobs") are typically seen. The characteristics of the spatial structure of the turbulence and their relationship to the time-averaged SOL profiles are discussed. The experimental observations are compared with 3-D non-linear numerical simulations of edge turbulence. Radial profiles of the poloidal wavenumber spectra and the poloidal scale length from the simulations are in reasonable agreement with those obtained from the experimental images, once the response of the optical system is accounted for. The resistive ballooning mode is the dominant linear instability in the simulations. The ballooning character of the turbulence is also consistent with fluctuation measurements made at the inboard and outboard midplane, where normalized fluctuation levels are found to be about ten times smaller on the inboard side. For discharges near the density limit, turbulent structures are seen on closed flux surfaces. Keywords: turbulence; edge plasma; fluctuations; transport phenomena; resistive instabilities.
Download or read book Nonlinear Turbulence Simulations for NSTX H modes written by M. H. Redi and published by . This book was released on 2004 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fusion Science and Technology written by and published by . This book was released on 2008 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Fast Visible Camera Divertor Imaging Diagnostic on DIII D written by and published by . This book was released on 2007 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent campaigns, the Photron Ultima SE fast framing camera has proven to be a powerful diagnostic when applied to imaging divertor phenomena on the National Spherical Torus Experiment (NSTX). Active areas of NSTX divertor research addressed with the fast camera include identification of types of EDGE Localized Modes (ELMs)[1], dust migration, impurity behavior and a number of phenomena related to turbulence. To compare such edge and divertor phenomena in low and high aspect ratio plasmas, a multi-institutional collaboration was developed for fast visible imaging on NSTX and DIII-D. More specifically, the collaboration was proposed to compare the NSTX small type V ELM regime [2] and the residual ELMs observed during Type I ELM suppression with external magnetic perturbations on DIII-D[3]. As part of the collaboration effort, the Photron camera was installed recently on DIII-D with a tangential view similar to the view implemented on NSTX, enabling a direct comparison between the two machines. The rapid implementation was facilitated by utilization of the existing optics that coupled the visible spectral output from the divertor vacuum ultraviolet UVTV system, which has a view similar to the view developed for the divertor tangential TV camera [4]. A remote controlled filter wheel was implemented, as was the radiation shield required for the DIII-D installation. The installation and initial operation of the camera are described in this paper, and the first images from the DIII-D divertor are presented.
Download or read book MEMS Based True Time Delay Lines for Phased Antenna Array Systems written by Yaping Liang and published by . This book was released on 2007 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tokamak Start Up Problems and Scenarios Related to the Transient Phases of a Thermonuclear Fusion Reactor Ettor Majorana International Science Series written by Heinz Knoepfel and published by Springer. This book was released on 2013-12-19 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the papers presented at the Course on "Tokamak Startup - Problems and Scenarios Related to the Transient Phases of a Thermonuclear Fusion Reactor" which was held in Erice, July 14-20, 1985. The fact that the critical startup and transient phases of a tokamak reactor are now the specific subject of a comprehensive international gathering of fusion specialists seems indicative of the substantial pro gress made in recent years towards attaining controlled ignition of a nuclear fusion fuel, i.e. towards demonstrating the scientific feasibili ty of controlled thermonuclear fusion. In fact, the steady-state burning phase has attracted so far most of the attention of fusion physicists and engineers, as it is conceptually more rewarding, and theoretically easier to handle. However, as for many large engineering systems, - nuclear fis- ... ':1' " . 10 ' ... Entrance to San Rocco's lecturing hall v sion power plants, or aerospace crafts, for example - the major issues of design and operation lie often in the startup, shutdown and power tran sieQt phases, rather than at the full load, or at cruising regimes. In ehoosing the contributions to this 7th Course of Prof. B.
Download or read book Plasma Science written by National Academies of Sciences Engineering and Medicine and published by . This book was released on 2021-02-28 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma Science and Engineering transforms fundamental scientific research into powerful societal applications, from materials processing and healthcare to forecasting space weather. Plasma Science: Enabling Technology, Sustainability, Security and Exploration discusses the importance of plasma research, identifies important grand challenges for the next decade, and makes recommendations on funding and workforce. This publication will help federal agencies, policymakers, and academic leadership understand the importance of plasma research and make informed decisions about plasma science funding, workforce, and research directions.
