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Title: Core Fueling of DEMO by Direct Line Injection of High-Speed Pellets From the HFS

Pellet injection represents to date the most realistic candidate technology for core fueling of a demonstration fusion power reactor tokamak fusion reactor. Modeling of both pellet penetration and fuel deposition profiles, for different injection locations, indicates that effective core fuelling can be achieved launching pellets from the inboard high field side at speeds not less than ~ 1 km/s. Inboard pellet fueling is commonly achieved in present tokamaks, using curved guide tubes; however, this technology might be hampered at velocities ≥ 1 km/s. An innovative approach, aimed at identifying suitable inboard "direct line'' paths, to inject high-speed pellets (in the 3 to 4 km/s range), has recently been proposed as a potential complementary solution. The fuel deposition profiles achievable by this approach have been explored using the HPI2 simulation code. The results presented here show that there are possible geometrical schemes providing good fueling performance. The problem of neutron flux in a direct line-of-sight injection path is being investigated, though preliminary analyses indicate that, perhaps, this is not a serious problem. The identification and integration of straight injection paths suitably tilted may be a rather difficult task due to the many constraints and to interference with existing structures. The suitabilitymore » of straight guide tubes to reduce the scatter cone of high-speed pellets is, therefore, of main interest. A preliminary investigation, aimed at addressing these technological issues, has recently been started. As a result, a possible implementation plan, using an existing Italian National Agency for New Technologies, Energy and Sustainable Economic Development-Oak Ridge National Laboratory facility is shortly outlined.« less
ORCiD logo [1] ; ORCiD logo [2] ;  [1] ; ORCiD logo [2] ;  [3] ;  [4] ;  [1] ;  [5] ;  [4]
  1. Italian National Agency for New Technologies, Frascati (Italy)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  3. Karlsruhe Institute of Technology, Karlsruhe (Germany)
  4. Max Planck Institute for Plasma Physics, Garching (Germany)
  5. Institut de Recherche sur la Fusion Magnetique, Saint-Paul-lez-Durance (France)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
IEEE Transactions on Plasma Science
Additional Journal Information:
Journal Volume: 46; Journal Issue: 5; Journal ID: ISSN 0093-3813
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; demonstration fusion power reactor (DEMO) tokamak fusion reactor; high field side (HFS) high-speed pellet injection; straight guide tubes
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1456780