OV/P6-15 Joint Research Using Small Tokamaks
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Engineering Optimization of Stellarator Coils Lead to Improvements in Device Maintenance
2015 IEEE 26th Symposium on Fusion Engineering (SOFE 2015) Austin, Texas, USA 31 May – 4 June 2015 IEEE Catalog Number: CFP15SOF-POD ISBN: 978-1-4799-8265-3 Copyright © 2015 by the Institute of Electrical and Electronics Engineers, Inc All Rights Reserved Copyright and Reprint Permissions: Abstracting is permitted with credit to the source. Libraries are permitted to photocopy beyond the limit of U.S. copyright law for private use of patrons those articles in this volume that carry a code at the bottom of the first page, provided the per-copy fee indicated in the code is paid through Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923. For other copying, reprint or republication permission, write to IEEE Copyrights Manager, IEEE Service Center, 445 Hoes Lane, Piscataway, NJ 08854. All rights reserved. ***This publication is a representation of what appears in the IEEE Digital Libraries. Some format issues inherent in the e-media version may also appear in this print version. IEEE Catalog Number: CFP15SOF-POD ISBN (Print-On-Demand): 978-1-4799-8265-3 ISBN (Online): 978-1-4799-8264-6 ISSN: 1078-8891 Additional Copies of This Publication Are Available From: Curran Associates, Inc 57 Morehouse Lane Red Hook, NY 12571 USA Phone: (845) 758-0400 Fax: (845) 758-2633 E-mail: [email protected] Web: www.proceedings.com TABLE OF CONTENTS ENGINEERING OPTIMIZATION OF STELLARATOR COILS LEAD TO IMPROVEMENTS IN DEVICE MAINTENANCE ..................................................................................................................................................1 T. Brown, J. Breslau, D. Gates, N. Pomphrey, A. Zolfaghari NSTX TOROIDAL FIELD COIL TURN TO TURN SHORT DETECTION .................................................................7 S. Ramakrishnan, W. -
The Fifth A3 Foresight Workshop on Spherical Torus
The Fifth A3 Foresight Workshop on Spherical Torus Feb. 15-17, 2017 Fontaine Blanche Hotel (丽水云泉大酒店), Kunming, Yunnan, China Organized by: Tsinghua University Yunnan Normal University Sponsors: National Natural Science Foundation of China (NSFC) Japan Society for the promotion of Science (JSPS) National Research Foundation of Korea (NRF) Agenda Presentation type: 30 min =25 min talk +5 min discussion 20 min =15 min talk +5 min discussion Tuesday, February 14, 2017 (Day 0, the lobby of the hotel) 14:00-17:30 Registration Wednesday, February 15, 2017 (Day 1, Yuntu Hall) 8:30-9:00 Registration 9:00-9:20 Opening President of Yunnan Normal University Prof. Z. Gao (Tsinghua U, China) Prof. Y. S. Hwang (Seoul National U, Korea) Prof. M. Inomoto (U Tokyo, Japan) 9:20-10:20 Session 1 Chair: GAO Zhe 9:20-9:50 Overview of VEST Prof. HWANG Yong Seok 9:50-10:20 Overview of UTST Prof. INOMOTO Michiaki 10:20-10:40 Coffee Break and Photo 10:40-11:40 Session 2 Chair: MAEKAWA Takashi 10:40-11:10 Overview of SUNIST Prof. GAO Zhe 11:10-11:40 Overview of TST-2 Prof. EJIRI Aira 11:40-13:40 Lunch 13:40-16:00 Session 3 Chair: RYU Chang Mo 13:40-14:10 Non-inductive startup studies on LATE Prof. MAEKAWA Takashi 14:10-14:40 Overview of TBM Program in ITER Prof. HONG Bong Guen 14:40-15:00 Fundamental Concept of High Field Side Mr. ELSERAFY Hatem injection of RF for EBW excitation in QUEST 15:00-15:20 Intermittent Plasma Bursts in Over-dense Mr. -
Physique Nucléaire Et De L'instrumentation Associée Introduction
FR0108546 # DEA-DAPNIA-RA-1997-98 A il. ..33/04 -DSM Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée Introduction Motivés par la curiosité pour les connaissances fondamentales et soutenus par des investissements impor- tants, les chercheurs du vingtième siècle ont fait des découvertes scientifiques considérables, sources de retombées économiques fructueuses. Une recherche ambitieuse doit se poursuivre. Organisé pour déve- lopper les grands programmes pour le nucléaire et par le nucléaire, le CEA est bien armé pour concevoir et mettre au point les instruments destinés à explorer, en coopération avec les autres organismes de recherche, les confins de l'infiniment petit et ceux de l'infinimenf grand. La recherche fondamentale évolue et par essence ne doit pas avoir de frontières. Le Département d'astrophysique, de physique des particules, de physique nucléaire et de l'instrumentation associée (Dapnia) a été créé pour abolir les cloisons entre la physique nucléaire, la physique des particules et l'as- trophysique, tout en resserrant les liens entre physiciens, ingénieurs et techniciens au sein de la Direction des sciences de la matière (DSM). Le Dapnia est unique par sa pluridisciplinarité. Ce regroupement a permis de lancer des expériences se situant aux frontières de ces disciplines tout en favorisant de nou- velles orientations et les choix vers les programmes les plus prometteurs. Tout en bénéficiant de l'expertise d'autres départements du CEA, la recherche au Dapnia se fait princi- palement au sein de collaborations nationales et internationales. Les équipes du Dapnia, de I'IN2P3 (Institut national de physique nucléaire et de physique des particules) et de l'Insu (Institut national des sciences de l'Univers) se retrouvent dans de nombreuses grandes collaborations internationales, chacun apportant ses compétences spécifiques afin de renforcer l'impact de nos contributions. -
SUNIST Spherical Tokamak
rd th SUNISTSUNIST The 3 IAEA TCM on Spherical Torus and the 11 STW, St. Petersburg Preliminary experiment of plasma current startup by ECR wave on SUNIST spherical tokamak HE Yexi, ZHANG Liang, *FENG Chunhua, FU Hongjun, GAO Zhe, TAN Yi, WANG Wenhao, *WANG Long, *YANG Xuanzong, XIE Lifeng [email protected], 86-10-62791874 (o), 86-10-62782658 (fax) SUNIST United Laboratory Department of Engineering Physics, Tsinghua University, Beijing 100084, P.R.China *Institute of Physics, Chinese Academy of Science, Beijing 100080, P.R.China This work was supported by JSPS-CAS Core-University Program on Plasma and Nuclear Fusion, the National Nature and Science Fund of China (Grant numbers: 10275041 and 10375089) , and International Atomic Energy Agency (Research contract No. 12935/R0) . SUNIST- Sino UNIted Spherical Tokamak UNISTSUNISTUNISTSUNIST OUTLINE SUNIST spherical tokamak Preliminary result Remained questions UNISTSUNISTUNISTSUNIST SUNIST spherical tokamak SUNIST United Laboratory SUNIST United Laboratory founded in 2004, consists of Department of Engineering Physics, Tsinghus University (DEP) ; Institute of Physics, Chinese Academy of Science (IOP) and keeping very close collaboration with Southwestern Institute of Physics (SWIP) and Institute of Plasma Physics, Chinese Academy of Science (IPPAS). Members of SUNIST Laboratory He, Yexi Department of Engineering Physics, Tsinghua University, Beijing 100084, P.R.China, 86-10- 62791874(lab), 86-10-62782658(fax), [email protected] (e-mail) Yang, Xuanzong Institute of Physics, -
Novel Concept for Disruption Mitigation in the ADITYA
28th IAEA Fusion Energy Conference (FEC 2020) Contribution ID: 1290 Type: Regular Poster Novel Concept for Disruption Mitigation in the ADITYA - U tokamak by Fast Time Response Electromagnetic Driven Pellet Impurity Injector Wednesday, 12 May 2021 17:00 (20 minutes) Implementation of suitable disruption mitigation technique remains the topmost priority for larger tokamaks including the ITER. The spontaneous disruption in ITER may probably be an unavoidable part, while operated with high performance D-T fuel [1]. Disruptions in ITER could produce very large heat loads on divertor tar- gets and other Plasma Facing Components (PFC), and large electromagnetic forces on the Vacuum Vessel (VV) can lead to structural damages [2]. In order to avoid these detrimental consequences, disruption mitigation is an essential part of tokamak research. The disruption mitigation system (DMS) in ITER is based on massive gas injection (MGI) of impurities, in order to radiate the plasma stored energy and mitigate the potentially damaging effects of disruptions [3]. Although, MGI based technique is suitable for most disruption mitiga- tion, there will be issues in case of having warning time less than 10 ms as may be the case for the onset of some disruptions in ITER [4]. This is due to the slow thermal velocity of the heavier impurity gas molecules, which limits the time needed to travel the distances before it reaches the plasma edge. At present, none of the currently planned disruption mitigations systems for ITER can respond on this time scale. The radiative dissipation of the plasma stored energy during major disruption in ITER by fast injection of massive pellets of low Z impurities, such as Li and Be pellet injection has been numerically modelled by Lukash et al. -
Overview of Recent Experimental Results from ADITYA Tokamak R
Tanna DOI:10.1088/1741-4326/aa6452 OV/4-3Rb Overview of Recent Experimental Results from ADITYA Tokamak R. Tanna1, J. Ghosh1, P. K. Chattopadhyay1, H. Raj1, S. Patel1, C. Gupta1, P. Dhyani2, K. A. Jadeja1, K. M. Patel1, S. B. Bhatt1, V. K. Panchal1, N. C. Patel1, C. Chavda1, E. V. Praveenlal1, K. S. Shah1, M. N. Makwana1, S. K. Jha1, M. V. Gopalakrishna1, K. Tahiliani1, D. Sangwan1, D. Raju1, U. C. Nagora1, S. K. Pathak1, P. K. Atrey1, S. Purohit1, Y. S. Joisa1, J. V. Raval1, C. V. S. Rao1, M. B. Chowdhuri1, S. Banerjee1, J. Thomas1, N. K. Ramaiya1, R. Manchanda1, A. Kumar1, P. K. Sharma1, S. V. Kulkarni1, K. Sathyanarayana1, B. K. Shukla1, A. Das1, R. Jha1, Y. C. Saxena1, A. Sen1, P. K. Kaw1, and D. Bora1 Rapporteured by: S. Pradhan 1Institute for Plasma Research (IPR), Bhat, Gandhinagar, India 2Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea Corresponding Author: R. Tanna, [email protected] Several experiments, related to controlled thermonuclear fusion research and highly relevant for large size tokamaks including ITER, have been carried out in ADITYA, an ohmically heated circular limiter tokamak. Repeatable plasma discharges of maximum plasma current of „160 kA and discharge duration beyond „250 ms with plasma current flattop duration of „140 ms has been obtained for the first time in ADITYA. The discharge reproducibility has been improved considerably with Lithium wall conditioning and improved plasma discharges are obtained by precisely controlling the plasma position. In these discharges, chord-averaged electron density „3:0–4:0 ˆ 1019{m3 using multiple hydrogen gas puffs, electron temperature of the order of „500– 700 eV have been achieved. -
Time Evaluation of Diamagnetic Loop and Mirnov Oscillations in a Major Plasma Disruption and Comparison with a Normal Shot
International Nano Letters https://doi.org/10.1007/s40089-018-0259-x ORIGINAL ARTICLE Time evaluation of diamagnetic loop and Mirnov oscillations in a major plasma disruption and comparison with a normal shot R. Sadeghi1 · Mahmood Ghoranneviss1 · M. K. Salem1 Received: 21 November 2018 / Accepted: 7 December 2018 © The Author(s) 2018 Abstract In this paper, plasma disruption was investigated in IR-T1 tokamak. Moreover, the time evaluation of plasma parameters such as plasma current, Ip; loop voltage, Vloop; power heating; and safety factor was illustrated. The results of diamagnetic loop and Mirnov oscillations in a major disruption were compared with their results in a normal shot. In addition, plasma disruption in diferent tokamaks was investigated and the results were compared with the IR-T1 tokamak. Keywords Disruption · Runaway electrons · Mirnov coils · Diamagnetic loop · Tokamak · MHD instability Introduction tokamak disruptions cause plasma confinement to be destroyed by restriction of current and density which ends Among various tools of magnetic confnement, tokamak to large mechanical stresses. Plasma disruption is caused containing hot plasma is one of the best and developed by strong stochastic magnetic feld formed due to nonlin- devices [1]. Tokamaks are divided into two groups: frst, the earity excited low-mode number magneto–hydro–dynamics large tokamaks for studying large plasmas such as DIII-D (MHD) modes. The safety factor (q) is very important in [2] and Tore–Supra [3] with high-cost testing conditions and determining stability and transport theory [9–13]. The paper second, small tokamaks such as STOR-M [4] and ISTTOK is organized as follows: in Sect. -
Edge Turbulence in ISTTOK: a Multi-Code Fluid Validation B Dudson, W Gracias, R Jorge, a Nielsen, J Olsen, P Ricci, C Silva, P
Edge turbulence in ISTTOK: a multi-code fluid validation B Dudson, W Gracias, R Jorge, A Nielsen, J Olsen, P Ricci, C Silva, P. Tamain, G. Ciraolo, N Fedorczak, et al. To cite this version: B Dudson, W Gracias, R Jorge, A Nielsen, J Olsen, et al.. Edge turbulence in ISTTOK: a multi-code fluid validation. Plasma Physics and Controlled Fusion, IOP Publishing, 2021. hal-03179634 HAL Id: hal-03179634 https://hal.archives-ouvertes.fr/hal-03179634 Submitted on 24 Mar 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Edge turbulence in ISTTOK: a multi-code fluid validation B. D. Dudson1, W. A. Gracias2, R. Jorge3;4, A. H. Nielsen5, J. M. B. Olsen5, P. Ricci3, C. Silva4, P. Tamain6, G. Ciraolo6, N. Fedorczak6, D. Galassi3;7, J. Madsen5, F. Militello8, N. Nace6, J. J. Rasmussen5, F. Riva3;8, E. Serre7 1York Plasma Institute, Department of Physics, University of York YO10 5DQ, UK 2Universidad Carlos III de Madrid, Leganés, 28911, Madrid, Spain 3École Polytechnique Fédérale de Lausanne (EPFL), Swiss Plasma Center (SPC), CH-1015 Lausanne, Switzerland 4Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal 5Department of Physics, Technical University of Denmark, Fysikvej, DK-2800 Kgs.-Lyngby, Denmark 6IFRM, CEA Cadarache, F-13108 St. -
Topical Review Solenoid-Free Plasma Start-Up in Spherical Tokamaks
Home Search Collections Journals About Contact us My IOPscience Solenoid-free plasma start-up in spherical tokamaks This content has been downloaded from IOPscience. Please scroll down to see the full text. 2014 Plasma Phys. Control. Fusion 56 103001 (http://iopscience.iop.org/0741-3335/56/10/103001) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 198.125.233.17 This content was downloaded on 06/01/2015 at 20:20 Please note that terms and conditions apply. Plasma Physics and Controlled Fusion Plasma Phys. Control. Fusion 56 (2014) 103001 (19pp) doi:10.1088/0741-3335/56/10/103001 Topical Review Solenoid-free plasma start-up in spherical tokamaks R Raman1 and V F Shevchenko2 1 William E. Boeing Department of Aeronautics and Astronautics, University of Washington, Seattle, WA 98195, USA 2 CCFE, Culham Science Centre, Abingdon, Oxon, OX14 3DB, UK E-mail: [email protected] Received 15 June 2014, revised 20 August 2014 Accepted for publication 1 September 2014 Published 22 September 2014 Abstract The central solenoid is an intrinsic part of all present-day tokamaks and most spherical tokamaks. The spherical torus (ST) confinement concept is projected to operate at high toroidal beta and at a high fraction of the non-inductive bootstrap current as required for an efficient reactor system. The use of a conventional solenoid in a ST-based fusion nuclear facility is generally believed to not be a possibility. Solenoid-free plasma start-up is therefore an area of extensive worldwide research activity. -
Modeling of the Hα Emission from ADITYA Tokamak Plasmas
atoms Article Modeling of the Hα Emission from ADITYA Tokamak Plasmas Ritu Dey 1,*, Malay B. Chowdhuri 1 , Joydeep Ghosh 1,2, Ranjana Manchanda 1, Nandini Yadava 3 , Umeshkumar C. Nagora 1,2, Parveen K. Atrey 1, Jayesh V. Raval 1, Y. Shankara Joisa 1, Rakesh L. Tanna 1 and ADITYA Team 1 1 Institute for Plasma Research, Bhat, Gandhinagar 382 428, India; [email protected] (M.B.C.); [email protected] (J.G.); [email protected] (R.M.); [email protected] (U.C.N.); [email protected] (P.K.A.); [email protected] (J.V.R.); [email protected] (Y.S.J.); [email protected] (R.L.T.) 2 Homi Bhaba National Institute, Anushakti Nagar, Mumbai 400 094, India 3 The National Institute of Engineering, Mysuru 570 008, Karnataka, India; [email protected] * Correspondence: [email protected] Received: 30 June 2019; Accepted: 3 October 2019; Published: 5 October 2019 Abstract: The spatial profile of Hα spectrum is regularly measured using a high-resolution multi-track spectrometer in ADITYA tokamak to study the neutral particle behavior. The Monte Carlo neutral particle transport code DEGAS2 is used to model the experimental Hα spectral emissions. Through the modeling of the spectral line profile of Hα, it is found that the neutral hydrogen, which is produced from molecular hydrogen and molecular hydrogen ion dissociation processes contributes 56% to the total Hα emission, and the atoms which are produced from charge-exchange process have 30% contribution. Furthermore, the experimentally measured spatial profile of chord integrated brightness was modeled for the two plasma discharges having relatively high and low density to understand the neutral particle penetration. -
An Application of Survival Analysis to Disruption Prediction Via Random Forests
An application of survival analysis to disruption prediction via Random Forests R.A. Tinguelyy, K.J. Montes, C. Rea, R. Sweeney, and R.S. Granetz Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA, USA 02139 Abstract. One of the most pressing challenges facing the fusion community is adequately mitigating or, even better, avoiding disruptions of tokamak plasmas. However, before this can be done, disruptions must first be predicted with sufficient warning time to actuate a response. The established field of survival analysis provides a convenient statistical framework for time-to-event (i.e. time-to-disruption) studies. This paper demonstrates the integration of an existing disruption prediction machine learning algorithm with the Kaplan-Meier estimator of survival probability. Specifically discussed are the implied warning times from binary classification of disruption databases and the interpretation of output signals from Random Forest algorithms trained and tested on these databases. This survival analysis approach is applied to both smooth and noisy test data to highlight important features of the survival and hazard functions. In addition, this method is applied to three Alcator C-Mod plasma discharges and compared to a threshold-based scheme for triggering alarms. In one case, both techniques successfully predict the disruption; although, in another, neither warns of the impending disruption with enough time to mitigate. For the final discharge, the survival analysis approach could avoid the false alarm triggered by the threshold method. Limitations of this analysis and opportunities for future work are also presented. Keywords: tokamak plasma, disruption prediction, survival analysis, machine learning, Random Forest, binary classification 1. -
UST 1 Stellarator and Status of the 3D Printed UST 2 Stellarator* on Leave of Absence Vicente from NFL, Queral CIEMAT L 1 Outline
UST_1 stellarator and Status of the 3D printed UST_2 stellarator Vicente M. Queral * Talk given in Columbia University, New York, NY, USA 1st October 2013 TM UST_1 stellarator and status of the 3D printed UST_2 stellarator* On leave of absence Vicente from NFL, Queral CIEMAT L 1 Outline Background Basic UST_1 and UST_2 data Design, construction and results in UST_1 ▪ Conceptual design of UST_1 ▪ Engineering design. Development of a construction method ▪ Validation of the construction method and design ▪ Results and conclusions Status of the 3D printed UST_2 stellarator ▪ Experimental validation of engineering concepts ▪ Conceptual design ▪ UST_2 engineering design. Fabrication tests ▪ Future work UST_1 stellarator and status of the 3D printed UST_2 stellarator Vicente Queral L 2 Background ► I am on a leave of absence period from the National Fusion Laboratory, CIEMAT, Spain. ► I worked in CIEMAT for almost 5 years, in Remote Handling, for IFMIF (International Fusion Materials Irradiation Facility), ITER and DEMO. ► Up to now, I have developed the work on stellarators on my own, with personal funds (for three years before CIEMAT work, at nights and weekends during CIEMAT work, and now 1.5 years during the leave of absence), with some help and contribution from CIEMAT. ► The work is R&D and innovation in engineering, focused in new construction methods for stellarators. It is not focused on physics and plasma experiments. UST_1 stellarator and status of the 3D printed UST_2 stellarator Vicente Queral L 3 Basic UST_1 data UST_1 modular stellarator • UST_1 stellarator was designed, built and operated from 2005 to 2007 in my personal laboratory. • Cost of the whole facility ~ 3000 € (many 2nd hand pieces).