Pub Date : 1998-01-01DOI: 10.1007/978-4-431-66879-4_204
K. Matsunaga, A. Nishimura, S. Satoh, O. Motojima
{"title":"Fiber Addition Effect to High-Tc Bulk","authors":"K. Matsunaga, A. Nishimura, S. Satoh, O. Motojima","doi":"10.1007/978-4-431-66879-4_204","DOIUrl":"https://doi.org/10.1007/978-4-431-66879-4_204","url":null,"abstract":"","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"117 1","pages":"861-864"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78573615","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}
Pub Date : 1998-01-01DOI: 10.1007/978-1-4615-5353-3_57
M. Osakabe, M. Sasao, M. Isobe, S. Itoh, T. Iida, A. Roquemore, L. C. Johnson
{"title":"\"Improvement of the Neutron Energy Spectrometer, COTETRA (Counter Telescope with Thick Radiator)\"","authors":"M. Osakabe, M. Sasao, M. Isobe, S. Itoh, T. Iida, A. Roquemore, L. C. Johnson","doi":"10.1007/978-1-4615-5353-3_57","DOIUrl":"https://doi.org/10.1007/978-1-4615-5353-3_57","url":null,"abstract":"","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"36 1","pages":"471-474"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74490281","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}
Pub Date : 1997-01-01DOI: 10.1016/B978-008042688-4/50018-1
Toshiyuki Mitoxa, S. Satoh, R. Maekawa, S. Yamada, K. Takahata, Akifiimi Iwamoto, H. Yamada, Kiyomasa Y. Watanabe, T. Baba, S. Moriuchi, K. Oba, H. Sekiguchi, K. Murai, K. Iimura, K. Nakamura, J. Yamamoto, O. Motojima
{"title":"Cryogenic Control System for the Large Helical Device","authors":"Toshiyuki Mitoxa, S. Satoh, R. Maekawa, S. Yamada, K. Takahata, Akifiimi Iwamoto, H. Yamada, Kiyomasa Y. Watanabe, T. Baba, S. Moriuchi, K. Oba, H. Sekiguchi, K. Murai, K. Iimura, K. Nakamura, J. Yamamoto, O. Motojima","doi":"10.1016/B978-008042688-4/50018-1","DOIUrl":"https://doi.org/10.1016/B978-008042688-4/50018-1","url":null,"abstract":"","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"1 1","pages":"79-82"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88572706","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}
T. Nishioka, K. Maehata, K. Ishibashi, M. Takeo, T. Mito, J. Yamamoto
General design equations are derived from one-dimensional energy balance equations for gas-cooled current leads of high temperature superconducting (HTSC) material. The equations are solved to evaluate general characteristics for cooling with a laminar flow gas. General characteristics arranged in the design chart are applicable to the design of current leads with a wide variety of geometrical dimensions. Thermal runaway in the case of accidental stoppage of the cooling gas and the transition to the normal state of part of the current leads is analyzed. The current leads optimized under the condition of self-sustained cooling are usable in a refrigerator cooling system, almost minimizing the total refrigerator load.
{"title":"Design Chart of High Temperature Superconducting Current Leads Cooled with Laminar Flow Gas","authors":"T. Nishioka, K. Maehata, K. Ishibashi, M. Takeo, T. Mito, J. Yamamoto","doi":"10.2221/JCSJ.30.560","DOIUrl":"https://doi.org/10.2221/JCSJ.30.560","url":null,"abstract":"General design equations are derived from one-dimensional energy balance equations for gas-cooled current leads of high temperature superconducting (HTSC) material. The equations are solved to evaluate general characteristics for cooling with a laminar flow gas. General characteristics arranged in the design chart are applicable to the design of current leads with a wide variety of geometrical dimensions. Thermal runaway in the case of accidental stoppage of the cooling gas and the transition to the normal state of part of the current leads is analyzed. The current leads optimized under the condition of self-sustained cooling are usable in a refrigerator cooling system, almost minimizing the total refrigerator load.","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"287 1","pages":"33"},"PeriodicalIF":0.0,"publicationDate":"1995-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85242451","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}
Pub Date : 1995-04-01DOI: 10.13182/FST95-A11962961
H. Momota, Y. Tomita, Miley G.H.
Analytical studies on a traveling wave direct energy converter (TWDEC) for D-{sup 3}He fueled fusion are carried out. The energy of 15 MeV carried by fusion protons is too high to handle with an electrostatic device. The TWDEC controls these high energy particles on the base of the principle of a Linac. This traveling wave method is discussed and the details of proton dynamics and excitation mechanism of electric power are clarified. The TWEDC consists of a modulator and decelerator. The applied traveling wave potential to the modulator modulates the velocity of fusion proton beams. This modulation makes a form of bunched protons at a down stream of the modulator. The decelerator has a set of meshed grids, each of which is connected to a transmission circuit. The phase velocity of excited wave on the transmission circuit is controlled the same way as that of decelerated protons. The kinetic energy 15 MeV of proton beams changes into an oscillating electromagnetic energy on the transmission circuit. This highly efficient direct energy converter of fusion protons brings a fusion reactor with a high plant efficiency. 4 refs., 4 figs.
{"title":"Analytical Studies on a Traveling Wave Direct Energy Converter for D-3He Fusion","authors":"H. Momota, Y. Tomita, Miley G.H.","doi":"10.13182/FST95-A11962961","DOIUrl":"https://doi.org/10.13182/FST95-A11962961","url":null,"abstract":"Analytical studies on a traveling wave direct energy converter (TWDEC) for D-{sup 3}He fueled fusion are carried out. The energy of 15 MeV carried by fusion protons is too high to handle with an electrostatic device. The TWDEC controls these high energy particles on the base of the principle of a Linac. This traveling wave method is discussed and the details of proton dynamics and excitation mechanism of electric power are clarified. The TWEDC consists of a modulator and decelerator. The applied traveling wave potential to the modulator modulates the velocity of fusion proton beams. This modulation makes a form of bunched protons at a down stream of the modulator. The decelerator has a set of meshed grids, each of which is connected to a transmission circuit. The phase velocity of excited wave on the transmission circuit is controlled the same way as that of decelerated protons. The kinetic energy 15 MeV of proton beams changes into an oscillating electromagnetic energy on the transmission circuit. This highly efficient direct energy converter of fusion protons brings a fusion reactor with a high plant efficiency. 4 refs., 4 figs.","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"91 1","pages":"286"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73397448","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}
Pub Date : 1995-04-01DOI: 10.13182/FST95-A11962953
Tsuguhiro Watanabe, T. Watari, N. Ohyabu
The application of radio-frequency (RF) forces to divertor plasma is proposed for the improvement of its relevance to reactors. RF fields are applied at the entrance of closed divertor rooms. Ponderomotive forces sustain high density scrape-off plasma which screens the penetration of neutral atoms into core plasma regions, and create positive electrostatic potential in scrape-off plasma region which suppresses the penetration of impurity ions form divertor rooms. Ponderomotive force for electron is also applied to prevent the upstream flow of cold electrons from divertor rooms to scrape-off regions. Theoretical and numerical studies are summarized. 2 refs., 3 figs.
{"title":"Advanced Divertor Concept - RF Divertor","authors":"Tsuguhiro Watanabe, T. Watari, N. Ohyabu","doi":"10.13182/FST95-A11962953","DOIUrl":"https://doi.org/10.13182/FST95-A11962953","url":null,"abstract":"The application of radio-frequency (RF) forces to divertor plasma is proposed for the improvement of its relevance to reactors. RF fields are applied at the entrance of closed divertor rooms. Ponderomotive forces sustain high density scrape-off plasma which screens the penetration of neutral atoms into core plasma regions, and create positive electrostatic potential in scrape-off plasma region which suppresses the penetration of impurity ions form divertor rooms. Ponderomotive force for electron is also applied to prevent the upstream flow of cold electrons from divertor rooms to scrape-off regions. Theoretical and numerical studies are summarized. 2 refs., 3 figs.","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"16 1","pages":"161"},"PeriodicalIF":0.0,"publicationDate":"1995-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81692212","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}
Y. Oka, Y. Takeiri, O. Kaneko, A. Ando, K. Tsumori, R. Akiyama, T. Kawamoto, T. Kuroda
To develop the powerful negative‐ion‐based neutral beam injection system for the large helical device, a 1/3 scaled H− source has been tested, which is immersed in the vacuum vessel. Intrinsic features of the vacuum‐immersed large H− source are described. Plasma density of higher than about 1012 e/cm3 is produced. During the beam extraction, it was found that a beam‐induced thin plasma exists in the vacuum vessel. In order to get a long pulse beam, this plasma was shielded and then the beam conditioning was completed up to the total beam energy of 70 keV for 100 ms, with the arc power up to about 50 kW. It is confirmed that H− current scaling as well as the plasma parameters would be similar to the scaling which is achieved by the previous 1/3 source.
{"title":"A Large Negative Ion Source Immersed in the Vacuum Vessel","authors":"Y. Oka, Y. Takeiri, O. Kaneko, A. Ando, K. Tsumori, R. Akiyama, T. Kawamoto, T. Kuroda","doi":"10.1063/1.1145054","DOIUrl":"https://doi.org/10.1063/1.1145054","url":null,"abstract":"To develop the powerful negative‐ion‐based neutral beam injection system for the large helical device, a 1/3 scaled H− source has been tested, which is immersed in the vacuum vessel. Intrinsic features of the vacuum‐immersed large H− source are described. Plasma density of higher than about 1012 e/cm3 is produced. During the beam extraction, it was found that a beam‐induced thin plasma exists in the vacuum vessel. In order to get a long pulse beam, this plasma was shielded and then the beam conditioning was completed up to the total beam energy of 70 keV for 100 ms, with the arc power up to about 50 kW. It is confirmed that H− current scaling as well as the plasma parameters would be similar to the scaling which is achieved by the previous 1/3 source.","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"163 1","pages":"65"},"PeriodicalIF":0.0,"publicationDate":"1994-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77990191","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}
Pub Date : 1994-01-01DOI: 10.1007/978-1-4615-2522-6_219
M. Shiotsu, K. Hata, A. Sakurai
{"title":"Effect of Test Heater Diameter on Critical Heat Flux in He II","authors":"M. Shiotsu, K. Hata, A. Sakurai","doi":"10.1007/978-1-4615-2522-6_219","DOIUrl":"https://doi.org/10.1007/978-1-4615-2522-6_219","url":null,"abstract":"","PeriodicalId":7974,"journal":{"name":"Annual Report of National Institute for Fusion Science","volume":"4 1","pages":"1797-1804"},"PeriodicalIF":0.0,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84734680","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：