Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027683
D. Mastrovito, W. Blanchard, J. Dong, R. Gernhardt, H. Kugel, G. Oliaro, T. Provost
The National Spherical Torus Experiment (NSTX) is the first step in an investigation of the physics principles of low-aspect-ratio spherical tori (ST) designed to study non-inductive start-up, current sustainability, current profile control, confinement, transport, pressure limits, stability and disruption resilience, as well as unique scrape-off layer (SOL) and divertor characteristics. NSTX started plasma operations in February 1999. During the first extended period of experiments, plasma discharge reproducibility and performance were strongly affected by impurity control and wall conditions. During this time, residual gas analyzer (RGA) data has been used during non-operating periods and between discharges to measure contributions to the vessel base-pressure (2-3E/sup -8/ Torr) that resulted from impurity gases evolving from internal surfaces. The RGA is a quadrupole mass spectrometer (QMS) with a Faraday Cup and electron multiplier. Recently, a second RGA system was installed to monitor fast changes in impurity gas production during and immediately after plasma discharges, which are indicative of changing conditions. In order to achieve the required response time, scan rates were increased by limiting the range of masses scanned. A data acquisition board was used to drive the new RGA system in concurrence with the NSTX shot cycle. Specialized interactive software to put acquired data into MDSplus, control data acquisition and assist in data analysis was written in Visual Basic and IDL.
{"title":"Residual gas analysis hardware and software data acquisition system at NSTX","authors":"D. Mastrovito, W. Blanchard, J. Dong, R. Gernhardt, H. Kugel, G. Oliaro, T. Provost","doi":"10.1109/FUSION.2002.1027683","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027683","url":null,"abstract":"The National Spherical Torus Experiment (NSTX) is the first step in an investigation of the physics principles of low-aspect-ratio spherical tori (ST) designed to study non-inductive start-up, current sustainability, current profile control, confinement, transport, pressure limits, stability and disruption resilience, as well as unique scrape-off layer (SOL) and divertor characteristics. NSTX started plasma operations in February 1999. During the first extended period of experiments, plasma discharge reproducibility and performance were strongly affected by impurity control and wall conditions. During this time, residual gas analyzer (RGA) data has been used during non-operating periods and between discharges to measure contributions to the vessel base-pressure (2-3E/sup -8/ Torr) that resulted from impurity gases evolving from internal surfaces. The RGA is a quadrupole mass spectrometer (QMS) with a Faraday Cup and electron multiplier. Recently, a second RGA system was installed to monitor fast changes in impurity gas production during and immediately after plasma discharges, which are indicative of changing conditions. In order to achieve the required response time, scan rates were increased by limiting the range of masses scanned. A data acquisition board was used to drive the new RGA system in concurrence with the NSTX shot cycle. Specialized interactive software to put acquired data into MDSplus, control data acquisition and assist in data analysis was written in Visual Basic and IDL.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"37 1","pages":"234-237"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91022141","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027652
N. Greenough, S. Depasquale, D. Lafrance
Recent developments in programmable logic devices have led to in-system programming capabilities for FPGA (field programmable logic array) and CPLD (complex programmable logic device) devices using inexpensive programming heads and PC-type computers. This development has major advantages for electronic equipment used in a research setting. Many of the devices are electrically erasable and re-programmable hundreds or thousands of times, allowing fast in-system circuit changes or error-correction in the field. This paper describes the successful application of a programmable logic device to a multi-channel phase detector for the HHFW RF systems on NSTX.
{"title":"A multi-channel phase detector using programmable logic devices","authors":"N. Greenough, S. Depasquale, D. Lafrance","doi":"10.1109/FUSION.2002.1027652","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027652","url":null,"abstract":"Recent developments in programmable logic devices have led to in-system programming capabilities for FPGA (field programmable logic array) and CPLD (complex programmable logic device) devices using inexpensive programming heads and PC-type computers. This development has major advantages for electronic equipment used in a research setting. Many of the devices are electrically erasable and re-programmable hundreds or thousands of times, allowing fast in-system circuit changes or error-correction in the field. This paper describes the successful application of a programmable logic device to a multi-channel phase detector for the HHFW RF systems on NSTX.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"108 1","pages":"99-102"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79219394","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027694
S. Ishida
Recently, JT-60U has intensively addressed enhancement and long sustainment of steady state performance in the use of negative-ion based neutral beam injection (N-NBI) and electron cyclotron (EC) wave injection. The N-NBI increased the current drive efficiency up to 1.55/spl times/10/sup 19/ A/m/sup 2//W at 360 keV and enhanced the fusion triple product up to n/sub i/(0)/spl tau//sub E/T/sub l/(0)/spl sim/3.0/spl times/10/sup 20/ keV sm/sup -3/ during, a full current drive condition. Increasing the plasma triangularity extended the duration of a plasma with /spl beta//sub N//spl sim/2.7 up to /spl sim/60 /spl tau//sub E/. The EC heating in combination with lower hybrid wave injection produced a very high electron temperature of /spl sim/26 keV for a reversed shear plasma. For reversed shear plasmas, the formation and sustainment of a central current hole was also discovered. High-field-side pellet injection extended the confinement up to H/sub 89p//spl sim/2 at n/n/sub G//spl sim/0.7. For the modification of JT-60, a fully superconducting tokamak, JT-60SC, is planned to further economical and environmental attractiveness in a tokamak DEMO reactor. The mission of JT-60SC is to realize high performance steady state operation and demonstrate the plasma applicability of low activation material for a plasma of break-even class relevant to the reactor plasma. Physics issues, design and machine description for JT-60SC with I/sub p/=4 MA, B/sub t/=3.8 T and R/sub p/=2.8 in are outlined.
{"title":"Recent results and future plan on JT-60U","authors":"S. Ishida","doi":"10.1109/FUSION.2002.1027694","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027694","url":null,"abstract":"Recently, JT-60U has intensively addressed enhancement and long sustainment of steady state performance in the use of negative-ion based neutral beam injection (N-NBI) and electron cyclotron (EC) wave injection. The N-NBI increased the current drive efficiency up to 1.55/spl times/10/sup 19/ A/m/sup 2//W at 360 keV and enhanced the fusion triple product up to n/sub i/(0)/spl tau//sub E/T/sub l/(0)/spl sim/3.0/spl times/10/sup 20/ keV sm/sup -3/ during, a full current drive condition. Increasing the plasma triangularity extended the duration of a plasma with /spl beta//sub N//spl sim/2.7 up to /spl sim/60 /spl tau//sub E/. The EC heating in combination with lower hybrid wave injection produced a very high electron temperature of /spl sim/26 keV for a reversed shear plasma. For reversed shear plasmas, the formation and sustainment of a central current hole was also discovered. High-field-side pellet injection extended the confinement up to H/sub 89p//spl sim/2 at n/n/sub G//spl sim/0.7. For the modification of JT-60, a fully superconducting tokamak, JT-60SC, is planned to further economical and environmental attractiveness in a tokamak DEMO reactor. The mission of JT-60SC is to realize high performance steady state operation and demonstrate the plasma applicability of low activation material for a plasma of break-even class relevant to the reactor plasma. Physics issues, design and machine description for JT-60SC with I/sub p/=4 MA, B/sub t/=3.8 T and R/sub p/=2.8 in are outlined.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"1 1","pages":"276-281"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86470593","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027724
G. Voss, E. Ciattaglia
The Mega Amp Spherical Tokamak (MAST) is an experimental fusion device currently operating at the Culham Science Centre. The low aspect ratio of the spherical tokamak combined with the need to develop a high flux swing from its central solenoid leads to high forces on the conductors that form the centre column. This column consists of a compact solenoid wound around the inner limbs of the toroidal field coils. In order to achieve the nominal plasma parameters, the dimensions of the centre column were optimised to make best possible use of the space available. The most critical region of the solenoid magnet design is the end turn and tail section where complex 3D magnetic fields interact with the current in the end turn conductors giving an asymmetric stress distribution. The hoop load in this end turn is particularly troublesome since it must be reacted across a bonded joint, which inevitably generates tensile and shear stresses within it. This paper describes how this problem has been solved for the new MAST centre column by the use of compact quadrupole tails formed close to the main coil and connected to it by tight bends formed in the water cooled copper conductor. A test coil employing these features and fitted with engineering diagnostics has been manufactured and tested at Culham to the maximum design current. This coil not only demonstrated the manufacturing processes involved but also provided test data, which compares well with engineering analysis.
Mega Amp球形托卡马克(MAST)是目前在Culham科学中心运行的实验性聚变装置。球形托卡马克的低长径比，加上需要从其中心螺线管发展高通量摆动，导致形成中心柱的导体受到高力。该柱由一个紧凑的螺线管组成，绕在环形场线圈的内肢上。为了达到标称等离子体参数，中心柱的尺寸进行了优化，以最大限度地利用可用空间。螺线管磁体设计中最关键的区域是端匝和尾部部分，复杂的三维磁场与端匝导体中的电流相互作用，产生不对称的应力分布。在这个末端转弯的环向载荷特别麻烦，因为它必须在一个粘合的关节上反应，这不可避免地在它内部产生拉伸和剪切应力。本文介绍了在新型桅杆中心柱上如何解决这一问题，即采用紧靠主线圈的紧凑型四极杆尾部，并通过水冷铜导体内形成的紧弯与主线圈相连。采用这些特性并配备工程诊断的测试线圈已在Culham制造并测试到最大设计电流。该线圈不仅演示了所涉及的制造过程，还提供了测试数据，与工程分析相比效果很好。
{"title":"Development of a high field solenoid magnet for the MAST Spherical Tokamak","authors":"G. Voss, E. Ciattaglia","doi":"10.1109/FUSION.2002.1027724","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027724","url":null,"abstract":"The Mega Amp Spherical Tokamak (MAST) is an experimental fusion device currently operating at the Culham Science Centre. The low aspect ratio of the spherical tokamak combined with the need to develop a high flux swing from its central solenoid leads to high forces on the conductors that form the centre column. This column consists of a compact solenoid wound around the inner limbs of the toroidal field coils. In order to achieve the nominal plasma parameters, the dimensions of the centre column were optimised to make best possible use of the space available. The most critical region of the solenoid magnet design is the end turn and tail section where complex 3D magnetic fields interact with the current in the end turn conductors giving an asymmetric stress distribution. The hoop load in this end turn is particularly troublesome since it must be reacted across a bonded joint, which inevitably generates tensile and shear stresses within it. This paper describes how this problem has been solved for the new MAST centre column by the use of compact quadrupole tails formed close to the main coil and connected to it by tight bends formed in the water cooled copper conductor. A test coil employing these features and fitted with engineering diagnostics has been manufactured and tested at Culham to the maximum design current. This coil not only demonstrated the manufacturing processes involved but also provided test data, which compares well with engineering analysis.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"8 1","pages":"409-412"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87648703","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027691
J. Feist
WENDELSTEIN 7-X, being under construction at the Greifswald branch of the Max-Planck-Institut fur Plasmaphysik, has the objective to prove the reactor relevance of a HELIAS type stellarator. Energy and particle confinement will be investigated in an optimised magnetic configuration and stationary operation of a reactor relevant divertor system will be demonstrated. After an intensive R&D program, the project is in the phase of procurement of the main components. This holds for the magnet system, the cryostat, the in-vessel components, the heating systems as well as for various tools for the assembly. Start of operation is scheduled for 2006.
{"title":"Status of WENDELSTEIN 7-X construction","authors":"J. Feist","doi":"10.1109/FUSION.2002.1027691","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027691","url":null,"abstract":"WENDELSTEIN 7-X, being under construction at the Greifswald branch of the Max-Planck-Institut fur Plasmaphysik, has the objective to prove the reactor relevance of a HELIAS type stellarator. Energy and particle confinement will be investigated in an optimised magnetic configuration and stationary operation of a reactor relevant divertor system will be demonstrated. After an intensive R&D program, the project is in the phase of procurement of the main components. This holds for the magnet system, the cryostat, the in-vessel components, the heating systems as well as for various tools for the assembly. Start of operation is scheduled for 2006.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"25 1","pages":"264-267"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89512459","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027708
R. Nygren, D. Youchison, J. Kim, K. Im, K.S. Kim, H.C. Park
Uncooled samples of various carbon fiber composites (CFCs), nominally 2.50 cm square and 1.00 cm in height were exposed in the Electron Beam Test System (EBTS) to heat fluxes up to /spl sim/100 MW/m/sup 2/ for shots typically of 1.5 s. The heat flux was focused on a square 1 /spl times/ 1 cm at the center of the sample. For NSTX (National Spherical Torus Experiment), five samples of Allied Signal 2-D CFC Type 865-19-4 were tested with 1.5 s shots at heat fluxes to 120 MW/m/sup 2/. For KSTAR (Korean Superconducting Tokamak Advanced Research) Project, a total of 37 samples of 29 various CFCs were tested. Duplicates samples with thermocouples were used to measure the absorbed heat and to calculate the fraction of the beam power absorbed. The samples were tested to 100 MW/m/sup 2/ with 1.5 s shots and then selected samples were tested at 60 MW/m/sup 2/ for shots up to 3.5 s. The most basic results from all of these tests is that, as expected, none of the samples fractured. For the KSTAR test, some samples achieved higher heat fluxes than others while their surface temperatures remained below a threshold of 2800/spl deg/C. Other observations presented in the paper are based on post-test examinations of the surface morphologies. The paper was presented in poster form at SOFE99 but not published there and is represented here.
{"title":"High heat flux tests of carbon composites for KSTAR and NSTX","authors":"R. Nygren, D. Youchison, J. Kim, K. Im, K.S. Kim, H.C. Park","doi":"10.1109/FUSION.2002.1027708","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027708","url":null,"abstract":"Uncooled samples of various carbon fiber composites (CFCs), nominally 2.50 cm square and 1.00 cm in height were exposed in the Electron Beam Test System (EBTS) to heat fluxes up to /spl sim/100 MW/m/sup 2/ for shots typically of 1.5 s. The heat flux was focused on a square 1 /spl times/ 1 cm at the center of the sample. For NSTX (National Spherical Torus Experiment), five samples of Allied Signal 2-D CFC Type 865-19-4 were tested with 1.5 s shots at heat fluxes to 120 MW/m/sup 2/. For KSTAR (Korean Superconducting Tokamak Advanced Research) Project, a total of 37 samples of 29 various CFCs were tested. Duplicates samples with thermocouples were used to measure the absorbed heat and to calculate the fraction of the beam power absorbed. The samples were tested to 100 MW/m/sup 2/ with 1.5 s shots and then selected samples were tested at 60 MW/m/sup 2/ for shots up to 3.5 s. The most basic results from all of these tests is that, as expected, none of the samples fractured. For the KSTAR test, some samples achieved higher heat fluxes than others while their surface temperatures remained below a threshold of 2800/spl deg/C. Other observations presented in the paper are based on post-test examinations of the surface morphologies. The paper was presented in poster form at SOFE99 but not published there and is represented here.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"19 1","pages":"345-347"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87377538","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}
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.
{"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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027697
S. Wukitch, W. Beck, E. Fitzgerald, R. Granetz, D. Gwinn, M. Grimes, J. Irby, E. Marmar, D. Terry, P. Titus, R. Vieira, S. Wolfe, J. Zaks, S. Bernabei, R. Ellis, L. Gereg, J. Hosea, D. Loesser, G. Schilling, J. Wilson
Recent Alcator C-Mod experimental campaigns have focused upon the study of the Advanced Tokamak regimes, which includes characterization of the RF heating, the formation and dynamics of internal barriers, H-mode edge pedestal, and divertor and scrape-off physics. The ICRF system has been recently upgraded with the improved performance of the 4-strap antenna. Total ICRF power in excess of 5 MW has been launched successfully into the plasma during this campaign. Due to the compact nature of C-Mod, the power feeds for the antenna are vacuum strip lines. Their orientation, to the tokamak B-field, is governed by maintaining E<15 kV/cm in locations where the RF E-field is parallel to tokamak B-field. Other modifications included improved protection tile grounding and installation of protective shields for Faraday screen ceramic isolators. The antennas also make use of BN protection tiles to eliminate high Z impurities from the antennas. The present empirical power limit results from arcing in a region of the antenna strap where E/spl sim/15 kV/cm and parallel to B and injections from the metallic fasteners used to attach the BN tiles to the antenna.
{"title":"Results and status of the Alcator C-Mod tokamak","authors":"S. Wukitch, W. Beck, E. Fitzgerald, R. Granetz, D. Gwinn, M. Grimes, J. Irby, E. Marmar, D. Terry, P. Titus, R. Vieira, S. Wolfe, J. Zaks, S. Bernabei, R. Ellis, L. Gereg, J. Hosea, D. Loesser, G. Schilling, J. Wilson","doi":"10.1109/FUSION.2002.1027697","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027697","url":null,"abstract":"Recent Alcator C-Mod experimental campaigns have focused upon the study of the Advanced Tokamak regimes, which includes characterization of the RF heating, the formation and dynamics of internal barriers, H-mode edge pedestal, and divertor and scrape-off physics. The ICRF system has been recently upgraded with the improved performance of the 4-strap antenna. Total ICRF power in excess of 5 MW has been launched successfully into the plasma during this campaign. Due to the compact nature of C-Mod, the power feeds for the antenna are vacuum strip lines. Their orientation, to the tokamak B-field, is governed by maintaining E<15 kV/cm in locations where the RF E-field is parallel to tokamak B-field. Other modifications included improved protection tile grounding and installation of protective shields for Faraday screen ceramic isolators. The antennas also make use of BN protection tiles to eliminate high Z impurities from the antennas. The present empirical power limit results from arcing in a region of the antenna strap where E/spl sim/15 kV/cm and parallel to B and injections from the metallic fasteners used to attach the BN tiles to the antenna.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"4 1","pages":"290-295"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72660976","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027731
K. Yoshikawa, K. Takiyama, K. Masuda, Y. Yamamoto, H. Toku, K. Nagasaki, H. Hashimoto, A. Nagafuchi, T. Mizutani, M. Ohnishi, H. Horiike
Potential measurements of the star-mode discharge in an inertial-electrostatic confinement fusion device were made by the laser-induced fluorescence (LIF) method by use of the Stark effects. Preliminary results show no noticeable potential, or electric fields compared with the center-spot mode discharge.
{"title":"Potential profile measurements by laser-induced fluorescence method in a helium discharge plasma","authors":"K. Yoshikawa, K. Takiyama, K. Masuda, Y. Yamamoto, H. Toku, K. Nagasaki, H. Hashimoto, A. Nagafuchi, T. Mizutani, M. Ohnishi, H. Horiike","doi":"10.1109/FUSION.2002.1027731","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027731","url":null,"abstract":"Potential measurements of the star-mode discharge in an inertial-electrostatic confinement fusion device were made by the laser-induced fluorescence (LIF) method by use of the Stark effects. Preliminary results show no noticeable potential, or electric fields compared with the center-spot mode discharge.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"5 1","pages":"438-441"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74701139","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}
Pub Date : 2002-11-07DOI: 10.1109/FUSION.2002.1027703
G. Bosia, G. Agarici, B. Beaumont, S. Bremond, K. Vulliez
Although it is generally recognized that the current IC technology is applicable to next step devices, the capability of current IC antennas to efficiently couple power to next step plasma is sometimes questioned. The ITER design effort has identified requirements for an acceptable performance. ITER-like IC antennas, fulfilling or possibly exceeding ITER requirements and designed for long pulse operation (1000 s) are currently being developed at Cadarache. In the paper, their essential features are described. Applications to existing and next step devices am discussed.
{"title":"High power density ion cyclotron antennas for next step device (applications)","authors":"G. Bosia, G. Agarici, B. Beaumont, S. Bremond, K. Vulliez","doi":"10.1109/FUSION.2002.1027703","DOIUrl":"https://doi.org/10.1109/FUSION.2002.1027703","url":null,"abstract":"Although it is generally recognized that the current IC technology is applicable to next step devices, the capability of current IC antennas to efficiently couple power to next step plasma is sometimes questioned. The ITER design effort has identified requirements for an acceptable performance. ITER-like IC antennas, fulfilling or possibly exceeding ITER requirements and designed for long pulse operation (1000 s) are currently being developed at Cadarache. In the paper, their essential features are described. Applications to existing and next step devices am discussed.","PeriodicalId":44192,"journal":{"name":"NINETEENTH CENTURY MUSIC","volume":"59 1","pages":"324-328"},"PeriodicalIF":0.4,"publicationDate":"2002-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74205972","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}
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