Progress in the MITICA beam source design

Abstract

In the framework of the development of the ITER neutral beam (NB) system, a test facility is planned to be built in Padova. A full size prototype of the ITER heating NB injector (MITICA) shall be built and tested at full beam power (17 MW) as per ITER requirements. The design of the MITICA beam source has further progressed following updated optimization and overall integration criteria. In the paper, the major design choices and revisions are presented, together with some results of numerical analyses carried out in order to assess the electrostatic and thermo-mechanical behaviour of the source.

Vacuum Tight Threaded Junctions (VTTJ): A new solution for reliable heterogeneous junctions in ITER

“…All the tests foreseen for the qualification of the VTTJ junction according to the ITER criteria (from 1.1 to 3.2) were passed by all the samples with electrodeposited finishing (1)(2)(3)(4)(5)(6)(7)(8) and by sample 10 (with laser welded finishing).…”

Progress in the realization of the PRIMA neutral beam test facility

“…The resulting negative ion beam at 1 MeV D − or 870 keV H − , after passing through a gas-cell neutralizer and electron dump (NED) and the electrostatic residual ion dump (E-RID), produces a ~17 MW Neutral Beam which will be intercepted by a target Calorimeter for a duration up to 3600 s [18,19]. All components of the MITICA injector will be contained in a vacuum vessel, made of stainless steel AISI 304 L, that is composed of two parts, the beam line vessel (BLV) and the beam source vessel (BSV), welded together on site for transportation reasons.…”

Benchmark of the SLACCAD code against data from the MANITU testbed at IPP

“…For negative ion beams, the most considered hypothesis on halo formation (see for example [8]) is that it could be generated on the downstream side of the Plasma Grid (PG), where there could be suitable conditions for the surface generation of H − /D − (in terms of grid temperature, cesium coverage and presence of H 0 /D 0 atoms that can impinge on the surface with proper energy). In the current design of the MITICA accelerator [9,10], halo particles are foreseen to contribute for a significant percentage of the total power impinging on the grids (about one third). Hence, it is very important, in particular for the design of the MITICA accelerator and related cooling systems, to assume a reasonable halo current.…”