Recent progress on design and development of the ITER equatorial EC launcher

ITER水平ECランチャー開発の進展

高橋 幸司; 小林 則幸; 春日井 敦; 坂本 慶司

Takahashi, Koji; Kobayashi, Noriyuki; Kasugai, Atsushi; Sakamoto, Keishi

ITER水平ランチャー設計・開発の進展について発表する。ランチャーは、フロントシールドと可動ミラーや導波管伝送機器,内部遮蔽体などを設置するポートプラグから構成され、可動ミラーによる20MWのRFビームパワーのトロイダル入射可変とランチャー機器やコイルを中性子から守る十分な遮蔽性能が要求される。設計及び各種解析から、フロントシードは熱的な構造健全性は担保するものの、支持構造が電磁力に対して厳しく、電磁力低減のためのスリット構造や分離型構造を検討する必要があることが判明した。可動ミラーについては、想定熱負荷及び電磁力に対して構造健全性が確保できることを確認した。可動ミラーの駆動源として超音波モータを適用し、駆動機構モックアップの実験を行うと同時に耐放射線性超音波モータの開発も行っている。また、RFビームの逆方向入射が可能となるような設計オプションの検討も行い、構造的な実現性を確認した。

The recent progress of the equatorial launcher design and development are presented. The launcher compose of a front shield and a port plug that three optical steering mirrors, waveguide components, internal shields and cooling pipes are installed. Toroidal steering capability of 20MW incident rf beam by the mirrors and a necessary nuclear shielding to protect the launcher components and tokamak coils are required for the launcher. It was verified that the design of the front shield withstood incremental temperature and induced stresses while EM forces on some of the shield modules were revealed large and the support structure might not tolerate enough. Therefore, the application of a slit structure or a separable first wall has sufficiently being considered. It was also found that the structure of the copper alloy plate ( 30mm in thickness) and several stainless steal tubes (inner diameter of 12mm) with flow speed of 4m/sec can remove the expected heat deposition in the mirror and tolerate the EM forces. An ultrasonic motor is a promising candidate for the steering mirror and has been applied for the mock-up of the drive system. The study of the nuclear radiation proof for the motor is under going. A counter ECCD from the equatorial port has recently being investigated. Since having both co- and cnt-steering capability is, however, not practical technically, one of three mirrors is possibly considered for the cnt-injection although the power of the co-injection is lost.