Search

Your search keyword '"Brémond, S."' showing total 6 results
Start Over Author "Brémond, S." Topic fusion reactors
6 results on '"Brémond, S."'

1. Modelling of Ion Cyclotron Wall Conditioning plasmas.

Author

Douai, D., Wauters, T., Lyssoivan, A., Marchuk, O., Wünderlich, D., Brémond, S., Lombard, G., Mollard, P., Pegourié, B., and Van Oost, G.

Subjects
ION cyclotron resonance spectrometry, PLASMA gases, FUSION reactors, POINT defects, TOROIDAL magnetic circuits, PLASMA injection, ELECTRON impact ionization
Abstract

Ion Cyclotron Wall Conditioning (ICWC) is envisioned in ITER to clean the wall from impurities, to control the wall isotopic ratio and the hydrogen recycling in the presence of the toroidal magnetic field. Various experiments and modelling are advancing to consolidate this technique. In this contribution the modeling of ICWC is presented, which can be divided in two parts: plasma description and plasma wall interaction. Firstly a 0D plasma model, based on a set of energy and particle balance equations for Maxwellian Hydrogen and Helium species, is presented. The model takes into account elementary collision processes, coupled RF power, particle confinement, wall recycling, and active gas injection and pumping. The RF plasma production process is based mainly on electron collisional ionization. The dependency of the plasma parameters, the Hydrogen and Helium partial pressures and neutral or ionic fluxes on pressure and RF power are quantitatively in good agreement with those obtained experimentally on TORE SUPRA. Secondly an extension of the 0D model including the description of the wall interaction is presented and compared to TORE SUPRA multi-pulse ICWC discharges. [ABSTRACT FROM AUTHOR]

Published
2011
Full Text
View/download PDF

2. Long Pulse operation with the ITER-Relevant LHCD Antenna in Tore Supra.

Author

Ekedahl, A., Delpech, L., Goniche, M., Guilhem, D., Hillairet, J., Preynas, M., Sharma, P. K., Achard, J., Bae, Y. S., Bai, X., Balorin, C., Baranov, Y., Basiuk, V., Bécoulet, A., Belo, J., Berger-By, G., Brémond, S., Castaldo, C., Ceccuzzi, S., and Cesario, R.

Subjects
FUSION reactors, MICROWAVE heating, ANTENNAS (Electronics), ELECTRIC discharges, INSTALLATION of equipment, PASSIVE components, PLASMA injection
Abstract

The aim of the Tore Supra tokamak is to address physics and technology issues of long pulse discharges. For this purpose, Tore Supra is equipped with two actively cooled Lower Hybrid Current Drive (LHCD) antennas (f = 3.7GHz), designed to operate in 1000s long pulses. One of these is the recently installed passive active multijunction (PAM) antenna, whose design is chosen for an LHCD system for ITER. The first experiments with the PAM antenna in Tore Supra have shown extremely encouraging results in terms of reflection coefficient behaviour and power handling. The maximum power and energy reached on the PAM, after ~500 pulses on plasma, was 2.7MW during 78s (exceeding 200MJ injected energy). In addition, 2.7MW has been coupled at a plasma-antenna distance of 10cm. The coupling behaviour on the PAM, characterised by the fraction of reflected power (RC), shows good agreement with the predictions from the ALOHA coupling code. Full non-inductive discharges lasting 50s have been sustained with the PAM alone, exhibiting a current drive efficiency comparable to that of the full active multijunction antennas in Tore Supra, in similar experimental conditions. [ABSTRACT FROM AUTHOR]

Published
2011
Full Text
View/download PDF

3. The ITER-like ICRH Launcher Project For JET.

Author

Durodié, F., Agarici, G., Amarante, G., Baity, F.W., Beaumont, B., Brémond, S., Chappuis, P., Damiani, C., Fanthome, J., Goulding, R.H., Hosea, J., Jones, G.H., Kaye, A., Lamalle, P.U., Loesser, G.D., Lorenz, A., Mead, M., Messineo, M.A., and Monakhov, I.

Subjects
ANTENNA arrays, ENGINEERING design, RADIO frequency, CYCLOTRONS, FUSION reactors, CAPACITORS
Abstract

The paper reports on the status of the JET ITER-Like ICRF Antenna project and highlights main challenges that have come up during its design phase. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2003
Full Text
View/download PDF

4. Development of a flight simulator for the control of plasma discharges

Author

Ravenel, N., Artaud, J.F., Brémond, S., Guillerminet, B., Huynh, P., Moreau, P., and Signoret, J.

Subjects
*COMPUTER networks, *PLASMA confinement, *PINCH effect (Physics), *FUSION reactors, *TOKAMAKS, *KEPLER'S equation
Abstract

Abstract: The feedback control of fusion experiments in tokamak devices is entering a new area driven by the increase of control requirements for obtaining burning plasmas under safe operation conditions. A project aiming at setting up a flight simulator for the development of advanced controllers has started last year at CEA. This simulator will reuse most of the components of the European Integrated Tokamak Modelling (ITM) simulation platform. Thus, it will benefit from the development made by the task force and it will be able to offer a development platform for the new controllers of present day European tokamaks and future machines. This paper provides an overview of the architecture of the simulator. The functional specifications of the simulator have been defined and the needs in interface implementation are analysed as well. [ABSTRACT FROM AUTHOR]

Published
2010
Full Text
View/download PDF

5. The CEDRES++ equilibrium code and its application to ITER, JT-60SA and Tore Supra

Author

Hertout, P., Boulbe, C., Nardon, E., Blum, J., Brémond, S., Bucalossi, J., Faugeras, B., Grandgirard, V., and Moreau, P.

Subjects
*COMPUTER software, *FUSION reactors, *TOKAMAKS, *MAGNETIC circuits, *PLASMA confinement, *FEASIBILITY studies
Abstract

Abstract: Free-boundary equilibrium codes are an essential tool for tokamak design studies and scenario development. In this contribution, the CEDRES++ code is presented and applications to ITER, JT-60SA and Tore Supra are reported on. A satisfactory benchmark of CEDRES++ with the DINA code was performed on an ITER Scenario 2 case at 32 different times across the discharge, both in direct and inverse mode. Ongoing design studies for the poloidal field coils system of JT-60SA, performed in the frame of the Broader Approach, were cross-checked with CEDRES++. Finally, a dimensioning study was carried out for the coils and power supplies for plasma vertical control in the frame of a feasibility study for the implementation of a divertor in Tore Supra. [Copyright &y& Elsevier]

Published
2011
Full Text
View/download PDF

6. Plasma control systems relevant to ITER and fusion power plants

Author

Kurihara, K., Lister, J.B., Humphreys, D.A., Ferron, J.R., Treutterer, W., Sartori, F., Felton, R., Brémond, S., and Moreau, P.

Subjects
*NUCLEAR reactor design & construction, *FUSION reactors, *PLASMA confinement, *TOKAMAKS, *BOOTSTRAP theory (Nuclear physics), *REAL-time control, *PLASMA instabilities
Abstract

Abstract: As a complement to ITER, the existing large and medium-size tokamaks are expected to explore more advanced operation scenarios compatible with a future power reactor. Specifically, the following urgent issues are required to be solved hopefully with an experimental demonstration: to work out one or more solutions to maintain a steady-state plasma with high performance (high beta and high bootstrap current fraction), and to suppress plasma instabilities almost completely. The developed solutions have to be confirmed using a DT burning plasma in ITER. In this article, we first review on system configurations and essential functions used for plasma control systems in existing tokamaks, from the viewpoint of technical inheritance of both hardware and software. Second, we discuss what plasma control system is relevant to ITER and fusion power plants from the two viewpoints: operation supervisor and plasma control tool. Finally, we will provide the current design of the ITER plasma control system. [Copyright &y& Elsevier]

Published
2008
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results