ALL METAL-SUPPORT FOR A CENTRAL CONDUCTOR OF THE ITER ICRF ANTENNA SYSTEM

Citation
S. Moriyama et al., ALL METAL-SUPPORT FOR A CENTRAL CONDUCTOR OF THE ITER ICRF ANTENNA SYSTEM, Fusion engineering and design, 39-4, 1998, pp. 134-142
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Nuclear Sciences & Tecnology
ISSN journal
0920-3796
Volume
39-4
Year of publication
1998
Pages
134 - 142
Database
ISI
SICI code
0920-3796(1998)39-4:<134:AMFACC>2.0.ZU;2-O
Abstract
One of the major critical points of the ion cyclotron antenna for next -generation Tokamaks is a ceramic support of a central conductor of a coaxial antenna feeder close to the plasma. Enhancement of dielectric loss tangent of ceramics due to neutron irradiation limits power injec tion capability of the antenna significantly. An all metal antenna sup port (AMS) employing a ridged waveguide was proposed. The central cond uctor of the coaxial line connected to the current strap of the antenn a is mechanically supported by the AMS. A design of the all metal supp ort was carried out using a calculation for both electrical characteri stics and mechanical strength. The electrical characteristics calculat ion with finite difference time domain (FDTD) method shows that the AM S can be used on the transmission line with quite a small reduction in power transmission capability. It was also confirmed that the mechani cal strength is enough against the force caused by eddy current with d isruption, with calculation. A real size mock-up of the AMS for low po wer RF characteristics measurement was fabricated. The RF measurement with the mock-up shows that the power reflection of the all metal supp ort is low enough (< 15%) and is close to the FDTD calculation results . (C) 1998 Elsevier Science S.A. All rights reserved.