Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor

Boron powder dropped into KSTAR plasmas decreased the radiated power, core electron density, and $Z_\mathrm {eff}$ , indicating that the ablated and redeposited boron powder helped to condition the plasma-facing surfaces. Visible line emission of oxygen and tungsten were also reduced by 50% (80%) wi...

Full description

Saved in:
Bibliographic Details
Main Authors: Hanna Schamis, Erik P. Gilson, Hyungho Lee, Rajesh Maingi, SangKyeun Kim, Joseph A. Snipes, SeongMoo Yang, Alessandro Bortolon, Juhyeok Jang, Boseong Kim, Dongcheol Seo, Jaein Song, Hyunmyeong Lee, the KSTAR collaboration
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:Nuclear Fusion
Subjects:
Online Access:https://doi.org/10.1088/1741-4326/adf123
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849411919857844224
author Hanna Schamis
Erik P. Gilson
Hyungho Lee
Rajesh Maingi
SangKyeun Kim
Joseph A. Snipes
SeongMoo Yang
Alessandro Bortolon
Juhyeok Jang
Boseong Kim
Dongcheol Seo
Jaein Song
Hyunmyeong Lee
the KSTAR collaboration
author_facet Hanna Schamis
Erik P. Gilson
Hyungho Lee
Rajesh Maingi
SangKyeun Kim
Joseph A. Snipes
SeongMoo Yang
Alessandro Bortolon
Juhyeok Jang
Boseong Kim
Dongcheol Seo
Jaein Song
Hyunmyeong Lee
the KSTAR collaboration
author_sort Hanna Schamis
collection DOAJ
description Boron powder dropped into KSTAR plasmas decreased the radiated power, core electron density, and $Z_\mathrm {eff}$ , indicating that the ablated and redeposited boron powder helped to condition the plasma-facing surfaces. Visible line emission of oxygen and tungsten were also reduced by 50% (80%) with boron injection into H-mode (L-mode) discharges that used the new KSTAR tungsten monoblock lower divertor. Dynamic particle balance analysis found a negligible difference in the inferred wall pumping rate during the steady portion of the discharges. It is inferred that the observed conditioning effects were principally caused by a reduction in intrinsic impurities as opposed to a reduction in wall recycling. These results are in qualitative agreement with low- Z injected powder experiments across many fusion devices, confirming the utility of low- Z powder injection as a real-time wall conditioning tool.
format Article
id doaj-art-bd7970cc31154c77a25e1dd3feed2598
institution Kabale University
issn 0029-5515
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series Nuclear Fusion
spelling doaj-art-bd7970cc31154c77a25e1dd3feed25982025-08-20T03:34:36ZengIOP PublishingNuclear Fusion0029-55152025-01-0165808603710.1088/1741-4326/adf123Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertorHanna Schamis0https://orcid.org/0000-0002-5685-2494Erik P. Gilson1https://orcid.org/0000-0001-6820-9132Hyungho Lee2Rajesh Maingi3https://orcid.org/0000-0003-1238-8121SangKyeun Kim4https://orcid.org/0000-0002-0701-8962Joseph A. Snipes5https://orcid.org/0000-0002-7077-5077SeongMoo Yang6https://orcid.org/0000-0003-1214-1268Alessandro Bortolon7https://orcid.org/0000-0002-0094-0209Juhyeok Jang8https://orcid.org/0000-0002-9991-6072Boseong Kim9Dongcheol Seo10Jaein Song11Hyunmyeong Lee12the KSTAR collaboration13Princeton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaPrinceton Plasma Physics Laboratory , Princeton, NJ, United States of AmericaKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfKorea Institute of Fusion Energy , Daejeon, Korea, Republic OfBoron powder dropped into KSTAR plasmas decreased the radiated power, core electron density, and $Z_\mathrm {eff}$ , indicating that the ablated and redeposited boron powder helped to condition the plasma-facing surfaces. Visible line emission of oxygen and tungsten were also reduced by 50% (80%) with boron injection into H-mode (L-mode) discharges that used the new KSTAR tungsten monoblock lower divertor. Dynamic particle balance analysis found a negligible difference in the inferred wall pumping rate during the steady portion of the discharges. It is inferred that the observed conditioning effects were principally caused by a reduction in intrinsic impurities as opposed to a reduction in wall recycling. These results are in qualitative agreement with low- Z injected powder experiments across many fusion devices, confirming the utility of low- Z powder injection as a real-time wall conditioning tool.https://doi.org/10.1088/1741-4326/adf123wall conditioningboron powder injectionplasma-material interactions
spellingShingle Hanna Schamis
Erik P. Gilson
Hyungho Lee
Rajesh Maingi
SangKyeun Kim
Joseph A. Snipes
SeongMoo Yang
Alessandro Bortolon
Juhyeok Jang
Boseong Kim
Dongcheol Seo
Jaein Song
Hyunmyeong Lee
the KSTAR collaboration
Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
Nuclear Fusion
wall conditioning
boron powder injection
plasma-material interactions
title Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
title_full Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
title_fullStr Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
title_full_unstemmed Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
title_short Wall conditioning effects of boron powder injection in KSTAR with a tungsten divertor
title_sort wall conditioning effects of boron powder injection in kstar with a tungsten divertor
topic wall conditioning
boron powder injection
plasma-material interactions
url https://doi.org/10.1088/1741-4326/adf123
work_keys_str_mv AT hannaschamis wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT erikpgilson wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT hyungholee wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT rajeshmaingi wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT sangkyeunkim wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT josephasnipes wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT seongmooyang wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT alessandrobortolon wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT juhyeokjang wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT boseongkim wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT dongcheolseo wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT jaeinsong wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT hyunmyeonglee wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor
AT thekstarcollaboration wallconditioningeffectsofboronpowderinjectioninkstarwithatungstendivertor