Physics and Technology in the Ion-cyclotron Range of Frequency on Tore Supra and TITAN Test Facility: Implication for ITER

Full text: The ITER ion-cyclotron range of frequency (ICRF) heating system, required to couple 20 MW of power to the plasmas in continuous wave (CW), have provide robust coupling for a variety of plasma scenarios with edge localized modes. To support the design of this system and to mitigate risks of operation in ITER, CEA has initiated some R and D programs accompanied by experiments together with modeling efforts. This paper reports recent results, including: 1. Test of a new Faraday screen (FS) concept electrically characterized by a slotted frame and cantilevered horizontal rods, on Tore Supra. RF sheath rectification is now better understood and included self-consistently in the ITER antenna physics design. 2. First operation of CW test bed facility TITAN. This consists in qualifying the Tore Supra ICRH antenna in long duration operation of 1000 s. 3. R and D of high permittivity materials for the load test of the antenna under ITER plasma conditions. In addition, results of the design of ITER ICRH scenarios using the full wave code EVE are reported, particularly the current drive efficiency calculation. In ITER, due to the simultaneous presence of multiple species there is no pure fast wave current drive configuration unlike present day experiments. Nevertheless, a current of ±200 kA in DT, or ±100 kA in DT(3He) could be driven on axis with 10 MW of power. (author)