TJ-II:Biasing probe: Difference between revisions

From FusionWiki
Jump to navigation Jump to search
No edit summary
No edit summary
Line 3: Line 3:


The impact of biasing on confinement properties has been studied to some depth.
The impact of biasing on confinement properties has been studied to some depth.
<ref>C. Hidalgo, M. Pedrosa, L. García, and A. Ware, ''Experimental evidence of coupling between sheared-flow development and an increase in the level of turbulence in the TJ-II stellarator'', [[doi:10.1103/PhysRevE.70.067402|Phys. Rev. E, '''70''' (2004) 067402]]</ref>
<ref>C. Silva et al, ''Transport and fluctuations during electrode biasing on TJ-II'', [[doi:10.1007/s10582-006-0044-3|Czech.  J. Phys. '''55''' (2005) 1589]]</ref>
<ref>C. Silva et al, ''Transport and fluctuations during electrode biasing on TJ-II'', [[doi:10.1007/s10582-006-0044-3|Czech.  J. Phys. '''55''' (2005) 1589]]</ref>
<ref>M.A. Pedrosa et al, ''Transport and fluctuations during electrode biasing experiments on the TJ-II stellarator'', [http://www-pub.iaea.org/MTCD/Meetings/FEC2006/ex_p4-40.pdf Proc. 12<sup>st</sup> Fusion Energy Conf. (2006) EX-P4/40]</ref>
<ref>M.A. Pedrosa et al, ''Transport and fluctuations during electrode biasing experiments on the TJ-II stellarator'', [http://www-pub.iaea.org/MTCD/Meetings/FEC2006/ex_p4-40.pdf Proc. 12<sup>st</sup> Fusion Energy Conf. (2006) EX-P4/40]</ref>

Revision as of 13:36, 8 May 2018

Layout of the biasing probe, mounted on the reciprocating probe drive

At TJ-II, a 2-D carbon composite mushroom shaped electrode (12 mm high with a diameter of 25 mm) has been developed and installed on a fast reciprocating probe drive. Typically, the electrode is inserted to a position 2 cm inside the last closed flux surface (LCFS) and biased positively (200-300 V) with respect to one of the two TJ-II limiters located in the Scrape-Off Layer region (about 0.5 cm beyond the LCFS). Measured electrode currents are in the range of 30-50 A.

The impact of biasing on confinement properties has been studied to some depth. [1] [2]

In 2009, the power source (originally DC) has been upgraded to allow modulation with a frequency of up to a few kHz.

Location: sector A4 (φ = 174.4 °). Signal names in the TJ-II database: 'PolI', 'PolV'.

Photo of the reciprocating drive of the biasing probe (top right)

References

  1. ↑ C. Silva et al, Transport and fluctuations during electrode biasing on TJ-II, Czech. J. Phys. 55 (2005) 1589
  2. ↑ M.A. Pedrosa et al, Transport and fluctuations during electrode biasing experiments on the TJ-II stellarator, Proc. 12st Fusion Energy Conf. (2006) EX-P4/40
Retrieved from "http://wiki.fusenet.eu/fusionwiki/index.php?title=TJ-II:Biasing_probe&oldid=6073"