Articolo in rivista, 2023, ENG, 10.1116/6.0002395
Sartori E.; Siragusa M.; Berton G.; Cavallini C.; Dal Bello S.; Fadone M.; Grando L.; Marcuzzi D.; Rizzetto D.; Serianni G.; Sonato P.; Zaupa M.; Dinh F.; Ferrara A.; Maccallini E.; Mura M.; Siviero F.; Toigo V.
Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Padova, Italy; Università degli Studi di Padova, Italy; CNR ISTP - Istituto per la Scienza e Tecnologia dei Plasmi, Sede di Padova, Italy; SAES Getters S.p.A., Lainate (MI), Italy.
An improvement for the vacuum system of the multidriver radio frequency (RF) prototype negative ion source SPIDER has been developed, to allow operating at high RF power, while minimizing the breakdown probability on the outside of the plasma source. A first-of-its-kind large nonevaporable getter (NEG) pump, based on a modular design of 384 cartridges totaling about 350 kg of ZAO® alloy (composed by Zr-Ti-V-Al) with an installed pumping speed at a room temperature of 330 m3/s for hydrogen, will complement the existing pumping system, based on eight cryogenic pumps and four turbomolecular pumps totaling about 90 m3/s in hydrogen. The vessel pressure during absorption is expected to be between 20 and 40 mPa, while during the getter regeneration, the peak operating pressure will be around 2 Pa. The NEG pump will use an additional vessel module, with integrated thermal shields to protect the in-vessel components during activation and regeneration of the pump, to be carried out at temperatures in the range of 550-600 °C. Integrated thermal analyses were carried out to verify the low heat load on pre-existing in-vessel components with a low limit of acceptable temperature, and to provide boundary conditions for the mechanical verifications of the pump structure. The scenario of cyclic hydrogen load was calculated considering the SPIDER operation modes, the expected gas throughput, and the cumulated load to the pump, to determine the regeneration temperature and auxiliary pumping necessary to make the regeneration duration compatible with the high availability of the system. The upgrade of the auxiliary pumping system is also described, as well as the mitigation of air or water exposure risk during regeneration of the NEG pump.
Journal of Vacuum Science & Technology B 41 (3), pp. 034202-1–034202-12
Thermal radiation, Ultra-high vacuum, Vacuum systems, Thermal analysis, Ion source
Serianni Gianluigi, Grando Luca, Toigo Vanni
ID: 481996
Year: 2023
Type: Articolo in rivista
Creation: 2023-05-26 16:01:30.000
Last update: 2023-11-22 10:41:41.000
External IDs
CNR OAI-PMH: oai:it.cnr:prodotti:481996
DOI: 10.1116/6.0002395
Scopus: 2-s2.0-85158848545
ISI Web of Science (WOS): 000979751800002