2011 IEEE/NPSS 24th Symposium on Fusion Engineering最新文献

{"title":"Fast ignition integrated experiments on GEKKO-LFEX laser facility","authors":"S. Fujioka, H. Azechi, H. Shiraga, N. Miyanaga, T. Norimatsu, N. Sarukura, H. Nagatomo, T. Johzaki, A. Sunahara","doi":"10.1109/SOFE.2011.6052352","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052352","url":null,"abstract":"Fast ignition realization experiments were carried out on GEKKO-LFEX laser facility. Present LFEX laser delivers 1.4 kJ of laser energy with 1.5 ps of pulse duration by two of four beams. This laser facility will be completed until the end of FY20111. Pedestal intensity of the LFEX laser is a critical parameter to determine coupling efficiency between the LFEX laser energy and compressed fuel core temperature, two new schemes have been successfully installed in the front end system of the LFEX laser to reduce the pedestal intensity. All diagnostics should be operated in the presence of intense background signal generated by intense LFEX laser and material interactions. Photodisintegration of iron atoms in the target chamber wall was found the dominant source of the background signal especially in the neutron time-of-flight measurement. Neutron yield were carefully evaluated with the consideration of the photodisintegration neutrons. A well-shielded x-ray streak camera measured the LFEX injection timing relative to the fuel compression timing with an accuracy of 10 ps. In the fast ignition integrated experiment, neutron yield was enhanced up to 3.5 × 107. The comparison between the simple modeling and experiment results reveals 20% of coupling efficiency was achieved.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"16 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113935265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overview of DIII-D off-axis neutral beam project","authors":"C. Murphy, M. Abrahim, P. Anderson, H. Chiu, H. Grunloh, M. Hansink, K. Holtrop, R. Hong, A. Kellman, D. Kellman, P. Mauzey, S. Noraky, C. Pawley, J. Rauch, J. Scoville, M. van Zeeland, H. Yip, R. Wood, M. Murakami, J.M. Park, W. Heidbrink","doi":"10.1109/SOFE.2011.6052323","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052323","url":null,"abstract":"DIII-D has four neutral beamlines (NB). Each of these beamlines has two ion sources, each of which injects up to 2.5 MW for 3 s. These beamlines intersect the vacuum vessel at an angle of 19.5 deg off from radial, enabling current drive in the same direction as the plasma current (co-injection). In 2004, one of these beamlines (210 deg) was rotated to provide counter-injection (opposite of plasma current). A different beamline (150 deg) has been modified to have the capability to provide off-axis neutral beam current drive. The goal of the off-axis injection is to have the center of the ion sources aimed at a position 40 cm below the geometric center of the plasma. To achieve this off-axis injection, the beamline requires a mechanical lifting system that can elevate the beamline up to 16.5 deg from horizontal. The beamline also requires more strongly vertically focused ion sources (in order to pass the beam through a reduced effective aperture) as well as modified internal components. Additionally, the design of the new internal components incorporated modifications to allow for the doubling of ion source pulse lengths without the need for active cooling. This paper discusses the various beamline system design requirements for off-axis injection, as well as the results from the actual commissioning of the beamline. Overviews of the design and performance of mechanical lifting system (hydraulics and controls), focused ion sources, flexible beamline support systems (vacuum, cryogenic, power and water cooling), and internal beamline collimators are included. Additionally, the in-vessel monitoring and shine-through protection requirements are discussed. The actual data obtained during beamline commissioning and during normal physics operations is also presented.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132300247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Korean R&D on the 6-pulse converter unit for ITER AC/DC converters","authors":"J. S. Oh, J. Choi, J. Suh, H. Liu, S. Lee, H. Park, W. Jung, S. Jo, H. Tan, J. Tao, P. Fu","doi":"10.1109/SOFE.2011.6052202","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052202","url":null,"abstract":"Korea is jointly responsible for the procurement package of ITER AC/DC converters shared between Korea and China. The collaborative activities among ITER Organization and Domestic Agencies under the frame of an Integrated Product Team have been underway since 2008 for the improvement and stabilization of the FDR2001 design. The Korean Domestic Agency has been being performing 2-staged converter R&D to establish the technical basis for the procurement package of ITER AC/DC converters adopting 5-inch thyristors. The first phase R&D demonstrated the basic features of ITER converter such as the proper clamping structure and current sharing of thyristors connected in parallel, and fault suppression capability (FSC) with a single-phase rectifier unit equivalent to an ITER vertical stabilization converter. The second phase R&D is intended to develop a full-scale 6-pulse ITER converter unit that realizes the full integration of all assemblies including AC bus bars and DC bus bars. The self supporting structure with aluminum material is designed to be safe from severe electromagnetic stress under high fault current. The suitable cooling design and the welding procedure have to be implemented in this structure. This paper shows the structural and thermal design. The current sharing among paralleled thyristors in each arms of the 6-pulse converter unit is improved. The design verification for FSC and the soundness over the electromagnetic stress is confirmed.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134340419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Key features in the operation of KSTAR","authors":"J. Kwak, Y. Oh, K. Kim, S. W. Kim, S. H. Hong, W. Chu, H. J. Lee, Y.O. Kim, J. Kim, S. Park, S. Hahn, M. K. Park, H. K. Kim, J. Bak, Y. Bae, W. Ko, S.G. Lee, J.H. Lee, J. Jung, K.D. Lee, Y. Nam, Y. Jeon, S. Yoon, A. England, W. C. Kim, K. Park, H. Na, H. Yang, M. Kwon","doi":"10.1109/SOFE.2011.6052198","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052198","url":null,"abstract":"The Korean Superconducting Tokamak Advanced Research (KSTAR) device is aimed at advanced tokamak (AT) research. Three years have passed since it achieved its first plasma in 2008. Because it is a superconducting machine and is pursuing AT research, it has unique features in terms of the machine engineering and operation. The toroidal field (TF) magnet coils are made of Nb3Sn, which provide high toroidal fields up to 3.5 T, and have been fully tested. The poloidal field (PF) magnet coils, consisting of both Nb3Sn and NbTi, which have a maximum current of 25 kA in their design, were tested up to 15 kA. A thermal hydraulic analysis is being conducted for PF magnet coil operation. All plasma facing components (PFCs) are equipped with water cooled graphite tiles and have the capability of being baked up to 350 °C. A startup scenario, which considered both the effect of the ferromagnetic material in the cable in conduit conductor (CICC) jacket in the magnet coils as well as a non-ferromagnetic up-down asymmetry in the cryostat structure, was developed and demonstrated its effectiveness by the last two year's reliable operations. Passive stabilizers and In-Vessel Control Coils (IVCC) are key components to realize AT Operation in KSTAR. The segmented IVCC coils were connected to form circular coils for internal vertical control in 2010 and diverted plasmas with high elongation (κ∼1.8, δ>0.6) were achieved. A neutral beam injection (NBI) system was developed aiming at 2 MW, 300 s per ion source which meets the long-pulse requirement of KSTAR. An NBI ion source with a power of 1.7 MW at 100 kV has been commissioned. Finally, ELMy H-modes were successfully produced with 1.3 MW NBI power at a plasma current of 0.6 MA in the 2010 campaign. The first H-mode discharge (#4200) in KSTAR was achieved one year earlier than officially planned and it was done at BT=2.0 T with Ip=0.6 MA in a well-balanced double null configuration after boronization on the PFC. Successful operations in the early days of KSTAR including H-mode experiments revealed the capability of advanced and steady-state operation which is essential for the International Thermonuclear Experimental Reactor (ITER) and future fusion reactors","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131029242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical analysis of buoyant-convective liquid metal flow in channels exposed to strong magnetic fields","authors":"C. Mistrangelo, L. Buhler","doi":"10.1109/SOFE.2011.6052204","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052204","url":null,"abstract":"In the currently proposed helium cooled lead lithium blanket design the liquid metal serves mainly to breed tritium and the heat flux is removed by helium flowing at high pressure in channels grooved in the walls. The use of a separate coolant has the advantage that the liquid metal can flow in the blanket with smaller velocities compared to those required in self-cooled blanket concepts. As a result the buoyant-convective flow caused by non-uniform thermal conditions and gravity may be comparable or even exceed the forced flow foreseen for tritium removal. Therefore, the knowledge of buoyancy-driven magnetohydrodynamic flows becomes fundamental to understand how the liquid metal circulates in the blanket. In this paper the main characteristics of magneto-convective duct flows are described. Effects of the direction of the temperature gradient with respect to the orientation of the applied magnetic field and the influence of electric conductivity of walls on the flow structure are investigated.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133290726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New IQ demodulator development in diagnostic equipment for fusion energy research","authors":"C. Kung, G. Kramer, J. Wilson","doi":"10.1109/SOFE.2011.6052240","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052240","url":null,"abstract":"New IQ demodulator, which will be used in the reflectometry system, was developed for the Alcator C-Mod experiments. Because the demodulator itself is a 4 mm × 4 mm integrated circuit chip and has very wide operational bandwidth (0.7 GHz – GHz), it can be mounted on a circuit board with its low frequency IQ outputs connecting directly to gain control and dc offset adjustment circuits. This whole circuitry is realized on a 4′×2.5″ printed circuit board and can be well tailored to meet the requirements for any type of data collection system. Since the RF and LO ports are operated at very narrow bandwidth in this application, single stub match circuits are designed to improve the ports matching as well as serve as a single pole filter.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132686537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Options for shielding Tokamak Cooling Water electrical components against high magnetic fields","authors":"K. Korsah, Michael Smith, Seokho Kim, C. Neumeyer","doi":"10.1109/SOFE.2011.6052270","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052270","url":null,"abstract":"The Tokamak Cooling Water System (TCWS) Instrumentation and Control (I&C) components of ITER will be located in areas of relatively high magnetic fields. Previous tests on electrical and I&C components have indicated that shielding will be required to protect these components from such magnetic fields. To accomplish this, studies were performed by AREVA Federal Services (AFS) in support of the TCWS Design project with the intent of identifying an optimal solution for shielding I&C components. This paper presents a summary of these studies and presents design options for providing magnetic shielding to ITER TCWS I&C components and electrical equipment that are susceptible to the magnetic fields present.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114479606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production of Tc-99m from naturally occurring molybdenum absent uranium","authors":"K. Pagdon, C. Gentile, A. Cohen, G. Ascione, G. Baker","doi":"10.1109/SOFE.2011.6052290","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052290","url":null,"abstract":"Technetium-99m (Tc-99m) is the world's most widely used medical isotope. Current production methods involve the irradiation of highly enriched uranium (HEU) and low enriched uranium (LEU) targets in nuclear reactors. Molybdenum-99 (Mo-99) is then extracted from these targets, which decays to Tc-99m. Currently, this process is centralized, as there are very few companies that manufacture Mo-99. In an effort to eradicate the need for uranium to produce this medical isotope, naturally occurring molybdenum was studied to produce Mo-99. Preliminary testing at Princeton Plasma Physics Laboratory included irradiating naturally occurring Mo coupons for varying amounts of time using a D-T neutron generator producing 1.5×108 n/sec to produce Mo-99. Exploiting this technique, Tc-99m was successfully produced. Proof of principle testing is also underway to confirm the ability to produce Mo-99 from Mo-100 using high-energy gamma rays. Future work consists of creating a mobile device that is able to produce Tc-99m on demand, allowing for a distributed system of the medical isotope in hospitals and radio pharmacies worldwide.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115103478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavior of metallic impurity in divertor configuration of Large Helical Device","authors":"C. Dong, E. Wang, S. Morita, M. Kobayashi, M. Goto, I. Murakami, N. Yamamoto","doi":"10.1109/SOFE.2011.6052233","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052233","url":null,"abstract":"Numerical transport study predicts that the edge surface layer in ergodic layer of Large Helical Device (LHD) has a favorable capability of impurity screening for materials of not only divertor plates but also vacuum vessel. In order to demonstrate the theoretical prediction, the density of iron originating in the LHD vacuum vessel made of stainless steel, which is not covered by carbon plates like tokamaks, is accurately determined with its radial profile using a space-resolved extreme ultraviolet (EUV) spectrometer, of which absolute intensity calibration is done with bremsstrahlung continuum. For the purpose effective intensity coefficients are precisely calculated for iron ions based on a collisional-radiative model. The iron ion density profiles of Fe14+, Fe15+, Fe22+ and Fe23+ are then evaluated with the radial emissivity profile reconstructed from chord-integrated profile and the effective intensity coefficient. The ratio of iron density to electron density integrated over the whole plasma volume can be finally calculated by fitting the iron density profile using one-dimensional impurity transport code. Thus, the analysis on the ratio gives a typical value of 8×10−7 in experimental campaign at last year. The entirely small value of the iron density demonstrates the theoretical prediction. The radial structure of transport coefficients are also obtained from the impurity transport code, showing a large inward convection velocity.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117335909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of a flexible liquid metal loop for investigation of MHD flows related to fusion blanket applications","authors":"L. Buhler, C. Mistrangelo, C. Koehly","doi":"10.1109/SOFE.2011.6052306","DOIUrl":"https://doi.org/10.1109/SOFE.2011.6052306","url":null,"abstract":"In order to investigate fundamental features of mag-netohydrodynamic (MHD) channel flows a closed liquid-metal circuit has been designed and manufactured in the MEKKA laboratory at the Karlsruhe Institute of Technology. This loop, which uses GaInSn as a model fluid, provides a flexible tool for studying properties of MHD lows and testing techniques for measuring electric potential and velocity for later use during experiments in ITER test blanket modules. Of particular interest is for instance the investigation of the stability of laminar MHD duct flow, the onset of turbulence and formation of quasi-2D turbulent structures as expected in intense magnetic fields. The main features of the loop are described and some numerical results used during its design are outlined.","PeriodicalId":393592,"journal":{"name":"2011 IEEE/NPSS 24th Symposium on Fusion Engineering","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124011840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}