Plasma-Facing Components in Tokamaks: Studies of Wall Conditioning Processes and Plasma Impact on Diagnostic Mirrors
2014 (English)Licentiate thesis, comprehensive summary (Other academic)
Understanding of material migration and its impact on the formation of co-deposited mixed material layers on plasma-facing components is essential for the development of fusion reactors. This thesis focuses on this topic. It is based on experiments performed at JET and TEXTOR tokamaks. The major objectives were to determine: (i) fuel and impurity removal from plasma-facing components by ICWC in different gas mixtures, (ii) fuel and impurity transport connected to ICWC operation, (iii) plasma impact on diagnostic mirrors. All these issues are in line with the ITER needs: mitigation of co-deposition and fuel inventory, and the performance of first mirrors in long-term operation. The novelty in research is demonstrated by several elements. In wall conditioning studies, tracer techniques based on injection of rare isotopes (N-15, O-18) were used to determine conclusively the impact of respective gases. Also, a new approach to ICWC was developed by combining global gas balance studies based on mass spectrometry and the use of multiple surface probes exposed to discharges and then studied ex-situ with accelerator-based techniques. Impact of plasma on diagnostic mirrors was determined after exposure to the entire first experimental campaign in JET-ILW.
Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2014. , xiv, 44 p.
TRITA-EE, ISSN 1653-5146 ; 2014:060
Plasa-wall interactions, wall conditioning, tracers, diagnostic mirrors, ICWC
Fusion, Plasma and Space Physics
Research subject Physics
IdentifiersURN: urn:nbn:se:kth:diva-154621ISBN: 978-91-7595-309-0OAI: oai:DiVA.org:kth-154621DiVA: diva2:758286
2014-11-07, Seminar room, Teknikringen 31, KTH- Royal Institute of Technology, Stockholm, 10:00 (English)
Cecconello, Marco, Doctor
Rubel, Marek, Professor
QC 201411032014-11-032014-10-262014-11-03Bibliographically approved
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