On the possiblity of direct electrical power extraction from scrape-off layer currents in tokamaks

0509569 - ÚFP 2020 RIV GB eng J - Journal Article
Komm, Michael - Stöckel, Jan - Adámek, Jiří - Kremers, B. - Vondráček, Petr - Bílková, Petra - Böhm, Petr - Šos, Miroslav - Pánek, Radomír
On the possiblity of direct electrical power extraction from scrape-off layer currents in tokamaks.
Plasma Physics and Controlled Fusion. Roč. 61, č. 9 (2019), č. článku 095017. ISSN 0741-3335. E-ISSN 1361-6587
R&D Projects: GA ČR(CZ) GA16-14228S; GA MŠMT(CZ) LM2015045
Institutional support: RVO:61389021
Keywords : divertor * non-ambipolarity * nuclear fusion * scrape-off layer currents * thermoelectric currents * Tokamak
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.829, year: 2019
Method of publishing: Limited access
https://iopscience.iop.org/article/10.1088/1361-6587/ab2739

Currents flowing in the scrape-off layer (SOL) are routinely observed in a number of tokamaks. They are usually closed through the divertor plates, either between the inner and outer target or between different poloidal sections of each target. The most common driving mechanisms of SOL currents are the thermoelectric effect (due to electron temperature difference between the two targets) and Pfirsch-Schlüter flows caused by radial pressure gradient. The SOL currents are commonly used for diagnostic purposes-e.g. as ELM monitors or for real-time estimation the divertor electron temperature. In this paper, we report on attempts to extract the SOL currents and related electrical power from the tokamak COMPASS using a dedicated insulated divertor tile and electronics setup, which allows for fast switching between grounded and floating state. It is observed that plasma acts as an ideal power source and that the magnitude of SOL currents scales with upstream separatrix temperature T e,sep.
Permanent Link: http://hdl.handle.net/11104/0300280