Takeuchi, Masaki; Sugie, Tatsuo; Ogawa, Hiroaki; Ishikawa, Masao; Shimada, Takahiko; Kusama, Yoshinori
Plasma and Fusion Research (Internet), 8(Sp.1), p.2402147_1 - 2402147_5, 2013/11
Divertor IR Thermography is one of the diagnostics which Japan is in charge of development in ITER project. The conceptual design has been performed so far, and the progress is reported here. By reducing the size of mirrors, and making the optical path a labyrinthine structure, the design of a new optics that fills requirements of both spatial resolution and neutron shielding has been advanced. To achieve the required measurement accuracy, the detected signal and the noises such as bremsstrahlung light, detector noise and thermal noise of optical components were evaluated. Higher photons than the bremsstrahlung light are obtained, excluding the low temperature range. The simulation calculation of reflection from wall was started. Detailed method of data processing of deriving the profiles of surface temperature in the divertor plates from the observed signals and in-situ calibration strategies of the optical system are important issues and will be discussed.
Yoshida, Masafumi; Hanada, Masaya; Kojima, Atsushi; Inoue, Takashi; Kashiwagi, Mieko; Grisham, L. R.*; Akino, Noboru; Endo, Yasuei; Komata, Masao; Mogaki, Kazuhiko; et al.
Plasma and Fusion Research (Internet), 8(Sp.1), p.2405146_1 - 2405146_4, 2013/11
Distributions of H and H in the source plasmas produced at the end-plugs of JT-60 negative ions source were measured by Langmuir probes and emission spectroscopy in order to experimentally investigate the cause of lower density of the negative ions extracted from end-plugs in the source. Densities of H and H in end-plugs of the plasma grid in the source were compared with those in the center regions. As a result, lower density of the negative ion at the edge was caused by lower beam optics due to lower and higher density of the H and H.
Kusakabe, Toshio*; Shiota, Kenji*; Shirai, Toshizo*
Plasma and Fusion Research (Internet), 8(Sp.1), p.2401145_1 - 2401145_4, 2013/11
no abstracts in English
Miyata, Yoshiaki; Suzuki, Takahiro; Ide, Shunsuke; Urano, Hajime; Fujita, Takaaki
Plasma and Fusion Research (Internet), 8(Sp.1), p.2405109_1 - 2405109_6, 2013/08
The precise control of the plasma position is a key issue in safe and stable plasma operation. A plasma equilibrium control simulator has been developed in order to study the techniques of plasma equilibrium control for JT-60SA. The simulator consists of an equilibrium solver and controller. The equilibrium solver identifies the plasma equilibrium under the given coil current and unknown eddy current by iteration. The function which calculates the self-consistent with magnetic flux consumption has been incorporated in order to simulate the control. The waveforms of JT-60SA plasma operation scenario during the ramp-up and the controllability of the plasma equilibrium control using the equilibrium control simulator were reported.
Ueno, Kenichi; Matsui, Kunihiro; Nishino, Toru; Isono, Takaaki; Okuno, Kiyoshi
Plasma and Fusion Research (Internet), 8(Sp.1), p.2405062_1 - 2405062_5, 2013/05
Japan Domestic Agency (JADA) for ITER will procure toroidal field (TF) coil structures and winding packs, and assemble them into a final TF coil configuration. Because the manufacturing schedule of the TF coils is on a critical path toward the first plasma of ITER, coil manufacturing must be successful and proceed on schedule. Therefore, risk assessment and management for the manufacturing are vital. JADA performed a risk assessment on the basis of past manufacturing experiences and risk mitigation policy for ITER. The results show that risks can be mitigated to a level that we can assure sufficint quality of the TF coil by sound design, manufacturing and quality management processes developed through R&D activities, and the use of prototypes.
Sasaki, Akira; Murakami, Izumi*
Plasma and Fusion Research (Internet), 8(Sp.1), p.2401021_1 - 2401021_4, 2013/03
We develop a CR model of W based on the computational atomic data for a variety of basic and application researches. We calculate the mean charge and radiative power loss from the plasma and the results are compared with those from different calculations and experimental data at the non-LTE kinetics workshops. We define the groups of levels, which have a same core configuration and one excited electron, and carry out iterative calculations increasing the number of groups according to the energy of the core state, to include a sufficient dielectronic recombination channels. We show the results agree well with other calculations and experiments
Sugiyama, Naoya*; Oyama, Gaku*; Matsubara, Fumiaki*; Saigusa, Mikio*; Kobayashi, Takayuki; Isayama, Akihiko; Moriyama, Shinichi
no journal, ,
Electron Cyclotron Current Drive (ECCD) is one of the most promising methods of heating and driving current in fusion plasmas. Incident wave into fusion plasmas should be converted from the linear polarization of a gyrotron output mode to the specific elliptical polarization in order to generate suitable plasma wave at high mode purity. The polarizer was designed at the frequency bands of 110,130 and 140 GHz based on the simulation results with the finite differential time domain method. The mock-up polarizer has been tested with low power at the both frequency bands of 110 GHz and 138 GHz. The high power model of wide-band polarizer was designed considering the results of low power test.