K E Thome, M E Austin, A Hyatt, A Marinoni, A O Nelson, C Paz-Soldan, F Scotti, W Boyes, L Casali, C Chrystal, S Ding, X D Du, D Eldon, D Ernst, R Hong, G R McKee, S Mordijck, O Sauter, L Schmitz, J L Barr, M G Burke, S Coda, T B Cote, M E Fenstermacher, A Garofalo, F O Khabanov, G J Kramer, C J Lasnier, N C Logan, P Lunia, A G McLean, M Okabayashi, D Shiraki, S Stewart, Y Takemura, D D Truong, T Osborne, M A Van Zeeland, B S Victor, H Q Wang, J G Watkins, W P Wehner, A S Welander, T M Wilks, J Yang, G Yu, L Zeng and the DIII-D Team
{"title":"Overview of results from the 2023 DIII-D negative triangularity campaign","authors":"K E Thome, M E Austin, A Hyatt, A Marinoni, A O Nelson, C Paz-Soldan, F Scotti, W Boyes, L Casali, C Chrystal, S Ding, X D Du, D Eldon, D Ernst, R Hong, G R McKee, S Mordijck, O Sauter, L Schmitz, J L Barr, M G Burke, S Coda, T B Cote, M E Fenstermacher, A Garofalo, F O Khabanov, G J Kramer, C J Lasnier, N C Logan, P Lunia, A G McLean, M Okabayashi, D Shiraki, S Stewart, Y Takemura, D D Truong, T Osborne, M A Van Zeeland, B S Victor, H Q Wang, J G Watkins, W P Wehner, A S Welander, T M Wilks, J Yang, G Yu, L Zeng and the DIII-D Team","doi":"10.1088/1361-6587/ad6f40","DOIUrl":null,"url":null,"abstract":"Negative triangularity (NT) is a potentially transformative configuration for tokamak-based fusion energy with its high-performance core, edge localized mode (ELM)-free edge, and low-field-side divertors that could readily scale to an integrated reactor solution. Previous NT work on the TCV and DIII-D tokamaks motivated the installation of graphite-tile armor on the low-field-side lower outer wall of DIII-D. A dedicated multiple-week experimental campaign was conducted to qualify the NT scenario for future reactors. During the DIII-D NT campaign, high confinement ( 1), high current ( 3), and high normalized pressure plasmas ( 2.5) were simultaneously attained in strongly NT-shaped discharges with average triangularity = −0.5 that were stably controlled. Experiments covered a wide range of DIII-D operational space (plasma current, toroidal field, electron density and pressure) and did not trigger an ELM in a single discharge as long as sufficiently strong NT was maintained; in contrast, to other high-performance ELM-suppression scenarios that have narrower operating windows. These strong NT plasmas had a lower outer divertor X-point shape and maintained a non-ELMing edge with an electron temperature pedestal, exceeding that of typical L-mode plasmas. Also, the following was achieved during the campaign: high normalized density ( / of at least 1.7), particle confinement comparable to energy confinement with , a detached divertor without impurity seeding, and a mantle radiation scenario using extrinsic impurities. These results are promising for a NT fusion pilot plant but further questions on confinement extrapolation and core-edge integration remain, which motivate future NT studies on DIII-D and beyond.","PeriodicalId":20239,"journal":{"name":"Plasma Physics and Controlled Fusion","volume":"17 1","pages":""},"PeriodicalIF":2.1000,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Physics and Controlled Fusion","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1361-6587/ad6f40","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, FLUIDS & PLASMAS","Score":null,"Total":0}
引用次数: 0
Abstract
Negative triangularity (NT) is a potentially transformative configuration for tokamak-based fusion energy with its high-performance core, edge localized mode (ELM)-free edge, and low-field-side divertors that could readily scale to an integrated reactor solution. Previous NT work on the TCV and DIII-D tokamaks motivated the installation of graphite-tile armor on the low-field-side lower outer wall of DIII-D. A dedicated multiple-week experimental campaign was conducted to qualify the NT scenario for future reactors. During the DIII-D NT campaign, high confinement ( 1), high current ( 3), and high normalized pressure plasmas ( 2.5) were simultaneously attained in strongly NT-shaped discharges with average triangularity = −0.5 that were stably controlled. Experiments covered a wide range of DIII-D operational space (plasma current, toroidal field, electron density and pressure) and did not trigger an ELM in a single discharge as long as sufficiently strong NT was maintained; in contrast, to other high-performance ELM-suppression scenarios that have narrower operating windows. These strong NT plasmas had a lower outer divertor X-point shape and maintained a non-ELMing edge with an electron temperature pedestal, exceeding that of typical L-mode plasmas. Also, the following was achieved during the campaign: high normalized density ( / of at least 1.7), particle confinement comparable to energy confinement with , a detached divertor without impurity seeding, and a mantle radiation scenario using extrinsic impurities. These results are promising for a NT fusion pilot plant but further questions on confinement extrapolation and core-edge integration remain, which motivate future NT studies on DIII-D and beyond.
期刊介绍:
Plasma Physics and Controlled Fusion covers all aspects of the physics of hot, highly ionised plasmas. This includes results of current experimental and theoretical research on all aspects of the physics of high-temperature plasmas and of controlled nuclear fusion, including the basic phenomena in highly-ionised gases in the laboratory, in the ionosphere and in space, in magnetic-confinement and inertial-confinement fusion as well as related diagnostic methods.
Papers with a technological emphasis, for example in such topics as plasma control, fusion technology and diagnostics, are welcomed when the plasma physics is an integral part of the paper or when the technology is unique to plasma applications or new to the field of plasma physics. Papers on dusty plasma physics are welcome when there is a clear relevance to fusion.