29th Symposium on Fusion Technology (SOFT 2016)

O2C.1 Manufacturing and test of the first ELM resilient long pulse ICRH antenna for WEST

6 Sep 2016, 11:00

20m

Meeting Hall V 2nd floor (Prague Congress Centre)

Board: 1

Oral B. Plasma Heating and Current Drive O2C

Speaker

Jean-Michel Bernard (CEA/DRF/IRFM)

Description

One of key missions of WEST (Tungsten (W) Environment in Steady-state Tokamak) is to pave the way towards the ITER actively cooled tungsten divertor procurement and operation. WEST PFC will operate in ITER conditions, i.e. with a heat flux on the divertor target of 10MW/m²2 during 1000s and 20MW/m²2 during a few tens of seconds. To achieve such heat flux levels, both Lower Hybrid Current Drive (LHCD) and Ion Cyclotron Resonant Heating (ICRH) systems are used. ICRH system is designed to operate at a power level of 9MW during 30s or 3MW during 1000s using three antennas. The WEST ICRH antennas [1-4] have been designed in a European collaboration and are now under fabrication at CAS/ASIPP, Hefei, within the framework of the Associated Laboratory IRFM-ASIPP. Since the WEST ICRH antennas have a CW operation requirement at high power, stringent specifications for the manufacturing process are necessary, such as material choice, high precision machining processes, etc. A specific welding sequence study was carried out for reducing the deformation during welding, dedicated fixation tools and jigs were designed for the fabrication and assembly, and the assembly workflow was optimized. This paper gives an overview of the manufacturing of the ICRH antenna sub-assemblies and the associated intermediate tests carried out. The work methods implemented for the pre-assembly are also presented. [1] Z. Chen et al., Fusion Eng. Des. 94 (2015) 82 [2] W. Helou et al., Fusion Eng. Des. 96-97 (2015) 473 [3] K. Vulliez et al., Fusion Eng. Des. 96-97 (2015) 611 [4] J. Hillairet et al., Proc. 21st Topical Conf. on Radiofrequency Power in Plasmas, Lake Arrowhead, CA (2015)