SESAME project Contract Number: 654935 Deliverable D3.7: CFD model of ALFRED primary loop

In the frame of SESAME Task 3.1.2, the entire primary loop of the ALFRED reactor is modelled by NRG and by CRS4. For this task, both institutes have made use of the CFD code STAR-CCM+. Part I of this report presents the CFD model and results of NRG. The CFD model of NRG is based on the ALFRED design from the LEADER project. The steady state CFD simulations NRG performed at nominal conditions showed that a thermal stratification develops in the pool of ALFRED with relatively high temperatures of up to 450 C close to the pool surface. It was demonstrated that this stratification can almost be removed by imposing a by-pass flow from the top of the pool to the top of the core. Part II of this report presents the CFD model and results of CRS4. The CFD model of CRS4 followed an alternative design of the ALFRED primary loop that was proposed by ANSALDO. A modular approach was adopted in the construction of the geometry allowing the simulation and analysis of a large number of configurations. The cold pool was separated in two communicating regions with the cold lead from the heat exchanger circulating along the reactor vessel before turning to the core, to keep the external vessel cold and minimize the thermal gradients in any condition. The nominal steady state operation was simulated at first, followed by PLOF and LOCA scenarios, in the context of a sensitivity study on the secondary cooling system and on the optimisation of the cold pools connection

@Misc{PMV19,
  author       = {Profir, M. and Moreau, V. and Visser, D.},
  title        = {SESAME project Contract Number: 654935 Deliverable D3.7: CFD model of ALFRED primary loop},
  month        = {may},
  year         = {2019},
  type         = {Rapport de Contrat},
  keywords     = {CFD simulation, thermal-hydraulics,ALFRED, pool modeling},
  url          = {https://publications.crs4.it/pubdocs/2019/PMV19},
}