Third harmonic X-mode electron cyclotron resonance heating on TCV using top launchFunded under: FP5-EAECTP C
A third harmonic electron cyclotron resonance heating system (X3) has been installed, commissioned and brought into service on the Tokamak à Configuration Variable (TCV). It comprises three 118GHz, 0.5MW gyrotrons designed to produce pulses up to 2 seconds long. In the present configuration, 1.0MW is launched vertically from the top of the vessel into the plasma and the remaining 0.5MW is launched horizontally from the low field side. X3 has been used to heat plasmas at density exceeding the 2nd harmonic cut-off significantly extending the operational space of additionally heated TCV plasmas. Studies have been performed to determine the optimal plasma/launcher configuration for X3 absorption for various plasma conditions and to find methods for real time feedback control of the X3 launcher. First experiments have been performed aimed at heating H-mode plasmas on TCV. First results show that the ELMs in TCV ohmic H-mode plasmas exhibit all characteristics of Type III ELMs. If, at moderate X3 power (<0.3MW), the additional heating is increased and then decreased, the ELM frequency first decreases and then increases again. At higher X3 power (>0.45MW) the Type III ELMs disappear and the H-mode discharge exhibits different MHD phenomena eventually disrupting.
Bibliographic Reference: A paper presented at: 19th IAEA Fusion Energy Conference. Organised by: International Atomic Energy Agency (IAEA). Held at: Lyon, France, October 14-19 2002.
Availability: Available online at: http://crppwww.epfl.ch/conferences/IAEA02/ Also published in EPFL Internal Report LRP 738/02, available free of charge from: École Polytechnique Fédérale de Lausanne, Ecublens, CH-1015 Lausanne. Fax: +41-21-6934747.
Record Number: 200315844 / Last updated on: 2003-01-31
Original language: en
Available languages: en