Conference paper. ALFRED Primary System: CFD Analysis of the Coolant Flow Path

Within Generation IV reactors, Lead cooled Fast Reactors technology is subject of growing interest thanks to numerous research, development and deployment initiatives in several national and international projects. The international FALCON (Fostering ALFRED CONstruction) consortium, led by Ansaldo Nucleare (IT), ENEA (IT) and ICN (RO), is dedicated to the development of ALFRED (Advanced Lead-cooled Fast Reactor European Demonstrator) and to its supporting research infrastructure in Romania. It aims at bridging the gap between the scientific basis and the industrial deployment of the technology. Recently, the FALCON consortium, assisted by several supporting organizations, has carried out a revision of the Reactor Coolant System design, improving numerous aspects also related to lead fluid dynamics. A main improvement is the elimination of thermal stratification on the Reactor Vessel upper region substantiated through dedicated CFD simulations of the Reactor Coolant System. Several options of dedicated openings have been investigated in three distinct design basis conditions: (i) normal operation, (ii) PLOF and (iii) PLOF + LOCA, being characterized by different lead free surface levels. Tracking free surfaces being numerically expensive, a steady state strategy is proposed, allowing the use of the same numerical model for different conditions, to explore the transients of interest through a quasi-stationary behavior in the long term. The paper describes the numerical model developed for the ALFRED Reactor coolant system, the sensitivity analyses performed and the resulting design optimizations. Finally, an analysis involving various reactor internal structure leakages is reported.

@Proceedings{MPCAF22,
  editor       = {Moreau, V. and Profir, M. and Caramello, M. and Alemberti, A. and Frignani, M.},
  title        = {Conference paper. ALFRED Primary System: CFD Analysis of the Coolant Flow Path},
  series       = {19th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-19) Brussels, Belgium, March 6 - 11, 2022, ISBN 9789076971261},
  year         = {2022},
  keywords     = {Gen-IV reactors, ALFRED, CFD, FALCON, pool thermal-hydraulics},
  url          = {https://publications.crs4.it/pubdocs/2022/MPCAF22},
}