NINETEENTH CENTURY MUSIC最新文献

{"title":"Electron cyclotron resonance frequency system on tokamak Aditya","authors":"B. Shukla, K. Sathyanarayana, D. Bora, S. Rajashree, K. Bhattacharya, B. Pal, S. Kulkarni, S. Gangopadhyay, Y. Srinivas, P. Khilar, M. Kushwah, R. Trivedi, D. Rathi, B. Kadia, A. Patel, C. Virani, P. Harsida, H. M. Jadav, K. Parmar, P. Shah, A. Makwana, S. Dani, P. Kirit, M. Harsha, J. Soni","doi":"10.1109/FUSION.2002.1027649","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027649","url":null,"abstract":"A 28 GHz ECRH system has been successfully commissioned on the tokamak Aditya to carry out breakdown, start up and heating experiments. The microwave source gyrotron VGA8000A19 capable of delivering 200 kW CW is commissioned and tested with a water dummy load for pulsed operation. The output mode of the gyrotron (TE/sub 02/) is externally converted to the HE/sub 11/ mode with the help of a mode converter and Matching Optics Unit of the transmission line. The transmission line consists of a mode converter, MOU, DC breaks, mitre bend, polarizer unit and different sizes of corrugated waveguides. The total transmission loss of the transmission line including 10 m long waveguides is measured to be less than 1.1 dB. The burn patterns at different locations of the transmission line confirm the mode purity to be better than 93% in the TE/sub 02/ mode. The transmission line terminates at a launcher box through a barrier window. The ECRH launcher consists of two mirrors to focus the microwave beam at the plasma center. The first mirror is convex while the second mirror is a concave focusing mirror. The mirrors are designed based on quasi optical analysis of the launcher system. The focal length of second mirror is 392.9 mm, which focuses the microwave beam to 35 mm (beam waist radius) at the plasma center. Beam steering in the plasma volume is restricted to /spl plusmn/2/spl deg/. The gyrotron is tested up to /spl sim/80 kW output power. A hard-wired interlock for various fault conditions, operates a rail-gap crowbar in less than 10 /spl mu/S to protect the gyrotron. The gyrotron output is coupled to the tokamak Aditya (O-mode, perpendicular launch from low field side) and successful breakdown of the neutral gas is observed at different tokamak parameters. The paper describes the technical aspects of commissioning of the ECRH system and breakdown results on Aditya.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"26 1","pages":"88-90"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83847489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Snowmass 2002: the fusion energy sciences summer study","authors":"N. Sauthoff, G. Navratil, R. Bangerter","doi":"10.2172/795778","DOIUrl":"https://doi.org/10.2172/795778","url":null,"abstract":"The Fusion Summer Study 2002 will be a forum for the critical technical assessment of major next-steps in the fusion energy sciences program, and will provide crucial community input to the long-range planning activities undertaken by the DOE and the FESAC. It will be an ideal place for a broad community of scientists to examine goals and proposed initiatives in burning plasma science in magnetic fusion energy and integrated research experiments in inertial fusion energy. This meeting is open to every member of the fusion energy science community and significant international participation is encouraged. The objectives of the Fusion Summer Study are three: 1. Review scientific issues in burning plasmas to establish the basis for the following two objectives and to address the relations of burning plasma in tokamaks to innovative magnetic fusion energy (MFE) confinement concepts and of ignition in inertial fusion energy (IFE) to integrated research facilities. 2. Provide a forum for critical discussion and review of proposed MFE burning plasma experiments (e.g., IGNITOR, FIRE, and ITER) and assess the scientific and technological research opportunities and prospective benefits of these approaches to the study of burning plasmas. 3. Provide a forum for the IFE community to present plans for prospective integrated research facilities, assess present status of the technical base for each, and establish a timetable and technical progress necessary to proceed for each. Based on significant preparatory work by the fusion community prior to the July Snowmass meeting, the Snowmass working groups will prepare a draft report that documents the scientific and technological benefits of studies of burning plasmas. The report will also include criteria by which the benefits of each approach to fusion science, fusion engineering/technology, and the fusion development path can be assessed. Finally, the report will present a uniform technical assessment of the benefits of the three approaches. The draft report will be presented and extensively discussed during the July meeting, leading to a final report. This report will provide critical fusion community input to the decision process of FESAC and DOE in 2002-2003, and to the review of burning plasma science by the National Academy of Sciences called for by FESAC and Energy Legislation which was passed by the House of Representatives. Members of the fusion community are encouraged to participate in the Snowmass working groups.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"20 1","pages":"156-158"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82436608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Status and plan of the HL-2A project","authors":"Jiancheng Yan, C. Zhou, Yong Liu, Dequan Liu","doi":"10.1109/FUSION.2002.1027735","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027735","url":null,"abstract":"This paper describes the outline of HL-2A project that is the first tokamak with a divertor in China. The recent achievements in the construction of the HL-2A tokamak is given. The development of major components and the installation of the machine are also described. The commissioning of HL-2A machine will start from the middle of 2002. The HL-2A experimental program and the future plan are sketched.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"1 1","pages":"461-464"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77500906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disruption design criteria for JET in-vessel components","authors":"V. Riccardo, P. Andrew, A. Kaye, P. Noll","doi":"10.1109/FUSION.2002.1027718","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027718","url":null,"abstract":"In view of the substantial modification in the JET plasma facing components foreseen for the 2004 shutdown, the design criteria for in-vessel components have been updated building up on the operational experience with divertor plasmas gained since the early '90s. Typically the most demanding design loads occur during disruptions and vertical displacement events (VDEs). In fast disruptions (e.g. density limit driven) the largest contribution to the loads comes from currents induced by fast change of the poloidal field, which tends to be proportional to the plasma current decay rate, the maximum of which has been observed to be linear with the pre-disruption plasma current. This implies that in the fastest events the current quench has a fixed duration at JET, about 10 ms. Usually VDEs take place on a longer time scale, and therefore halo currents determine the worst loading condition in these cases. Analysis of recent VDE data confirmed the previously observed magnitude of asymmetries: the toroidal peaking factor (TPF) up to 1.8 in upward VDEs and up to 1.4 in downward VDEs; the ratio average poloidal halo to initial plasma current (f) up to 23% in upward VDEs and up to 30% in downward VDEs. Experimental evidence to justify the new criteria and recipes on how to apply them to JET are included. The data used for the revision of the design criteria are discussed and compared with the assumptions used in the design of the components already present in the JET vacuum vessel.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"91 1","pages":"384-387"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80520710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and engineering of the Alcator C-Mod lower hybrid current drive system","authors":"G. Loesser, J. Rushinski, S. Bernabei, J. Hosea, J. Wilson, B. Beck, R. Parker","doi":"10.1109/FUSION.2002.1027632","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027632","url":null,"abstract":"The PSFC group of MIT and PPPL are jointly developing a Lower Hybrid Current Drive (LHCD) system for installation on the Alcator C-Mod tokamak, with the primary goal of driving plasma current. Twelve Klystrons will feed a coupler with an input power of 3 MW at 4.6 GHz and a pulse length of 5 seconds. The coupler is composed of 4 arrays, each with 24 wave-guides (96 total) which are stacked poloidally and are symmetric about both the vertical and horizontal planes. The four-stacked arrays are installed through a single equatorial port and can be axially adjusted to provide optimum plasma coupling. Material selections and spatial limitations required innovative design solutions that will be described.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"8 1","pages":"20-22"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80693699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of advanced physics and technology on the attractiveness of tokamak fusion power plants","authors":"F. Najmabadi","doi":"10.1109/FUSION.2002.1027630","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027630","url":null,"abstract":"During the past ten years, the ARIES Team has studied a variety of tokamak power plants with different degrees of extrapolation in plasma physics and technology from present database. Continuation of research has allowed us to apply lessons learned from each ARIES design to the next. The results of ARIES tokamak power plant studies provide a large body of data that highlight the tradeoffs and relative leverage of advanced plasma physics and fusion technology directions. Our results indicate that for the same plasma physics (e.g., first-stability) and technology extrapolation, steady state operation is more attractive than pulsed-plasma operation. Dramatic improvement over first-stability operation can be obtained through either utilization of high-field magnets (e.g., high-temperature superconductors) or operation in advanced-tokamak modes (e.g., reversed-shear). In particular, if full benefits of reversed-shear operation are realized, as is assumed in ARIES-AT, tokamak power plants will have a cost of electricity competitive with other sources of electricity. In technology area, emerging technologies such as advanced Baryon cycle, high-temperature superconductor, and advanced manufacturing techniques can improve the cost and attractiveness of fusion plants. For blankets, liquid breeder/coolants are the most attractive because most of neutron power is directly deposited in the coolant. This property can be exploited to arrive at a blanket design with a coolant outlet temperature higher than the structure temperature in the radiation zone. The high coolant temperature leads to a high thermal conversion efficiency (as in ARIES-ST and ARIES-AT blankets). The dual-cooled (He and LiPb) ARIES-ST blanket using ferritic steel structural material represents a near-term option for fusion systems and achieves a thermal efficiency of 45%. Development of high-performance SIC composites leads to the high-performance ARIES-AT blanket (SiC composite/LiPb coolant) that achieves 59% thermal conversion efficiency as well as the full potential safety and environmental features of fusion power.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"201 1","pages":"10-15"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80140424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear burn control in fusion reactors","authors":"E. Schuster, M. Krstić, G. Tynan","doi":"10.1109/FUSION.2002.1027729","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027729","url":null,"abstract":"Control of plasma density and temperature magnitudes, as well as their profiles, are among the most fundamental problems in fusion reactors. Unfortunately, the economy of fusion reactors often requires the reactor to operate under conditions in which the rate of thermonuclear reaction increases as the plasma temperature rises. In this thermally unstable zone, an active control system is necessary to stabilize the thermonuclear reaction. Existing efforts use control techniques for linear models. In this work, a zero-dimensional nonlinear model involving approximate conservation equations for the energy and the densities of the species was used to synthesize a nonlinear feedback controller for stabilizing the burn condition of a fusion reactor. The controller makes use simultaneously of the modulation of auxiliary power, the modulation of fueling rate and the controlled injection of impurities as actuators. A computer simulation study was performed to show the capability of the controller and compare it with previous linear controllers.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"16 1","pages":"430-433"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73037787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polymer-derived SiC/sub f//SiC/sub m/ composite fabrication and microwave joining for fusion energy applications","authors":"R. Bruce, S. Guharay, F. Mako, W. Sherwood, E. Lara-Curzio","doi":"10.1109/FUSION.2002.1027728","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027728","url":null,"abstract":"Reports experimental results for the very first batch of products obtained by joining silicon carbide fiber-reinforced-silicon carbide matrix composites for fusion applications. The starting point of the work has been to fabricate and join matched pairs of SiC/sub f//SiC/sub m/ composites. The composites were joined in a microwave heating environment using preceramic polymer slurry as the joining material. Several key properties of these composites and joints were investigated, including measurements of density, flexural stress, and thermal conductivity. Measurements of our very first batch of products showed the average flexural stress for the intrinsic material at room temperature was 287.1 MPa. The composite exhibited crack deflection during fracture at room temperature. At 1100C, the average flexural stress dropped to 103.7 MPa and the composite exhibited brittle fracture. We obtained the in-plane thermal conductivity of the intrinsic material was 13.3 W/m-K at room temperature and 8.7 W/m-K at 1000C. The cross-plane thermal conductivity was 3.8 W/m-K at room temperature and 4.1 W/m-K at 1000C. Butt-joined bend bars had an average flexural stress of 31.9 MPa. Dovetail-joined bend bars had an average flexural stress of 39.0 MPa. The maximum value obtained for the dovetail-joined bend bars was 48.1 MPa. Optimization of the process parameters and detailed characterization are in progress to build a strong database and yield high-quality products for first wall structural material.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"22 1","pages":"426-429"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78137997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The NSTX trouble reporting system","authors":"S. Sengupta, G. Oliaro","doi":"10.2172/795714","DOIUrl":"https://doi.org/10.2172/795714","url":null,"abstract":"An online trouble reporting system (TRS) has been introduced at NSTX. The TRS is used by NSTX operators to report problems that affect NSTX operations. The purpose of the TRS is to enhance NSTX reliability and maintainability by identifying components, occurrences, and trends that contribute to machine downtime. All NSTX personnel have access to the TRS. The user interface is via a Web browser, such as Netscape or Internet Explorer. This Web-based feature permits any X-terminal, PC, or MAC access to the TRS. The TRS is based upon a trouble reporting system developed at the DIII-D Tokamak, at General Atomics Technologies (Petersen and Miller, 1991). This paper provides a detailed description of the TRS software architecture, user interface, MS SQL server interface and operational experiences. In addition, sample data from the TRS database are summarized and presented.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"13 1","pages":"242-244"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83808766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear considerations for FIRE","authors":"M. Sawan, H. Khater","doi":"10.1109/FUSION.2002.1027675","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027675","url":null,"abstract":"Nuclear analyses have been performed for the baseline design of the Fusion Ignition Research Experiment (FIRE). Nuclear heating, structural radiation damage, and magnet insulator dose were evaluated. Critical issues requiring additional R&D effort include low-temperature embrittlement of copper and identifying insulators that can handle a dose as high as 1.5/spl times/10/sup 10/ Rads under the FIRE load conditions. Activation calculations were performed to determine the amount of radioactivity and decay heat generated. Accessibility for hands-on maintenance was assessed. All components qualify as low level waste.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"60 1","pages":"196-199"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90949638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"艺术学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}