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Experiments for Lead Cooled Reactors


Benchmark Experiments At BFS Facilities For Pb (Pb-Bi) Critical Media Integral Parameters Testing

Tech Area / Field

  • FIR-EXP/Experiments/Fission Reactors
  • FIR-ISO/Isotopes/Fission Reactors
  • FIR-NOT/Nuclear and Other Technical Data/Fission Reactors

3 Approved without Funding

Registration date

Leading Institute
FEI (IPPE), Russia, Kaluga reg., Obninsk


  • CEA / DCC / CEN Cadarache, France, Cadarache\nJapan Nuclear Cycle Development Institute / O-arai Engineering Center, Japan, Ibaraki

Project summary

The past five years have been marked by a considerable interest of nuclear physics and technology specialists to possibilities promised by a new concept of fast neutrons based reactor facilities. The concept is suggesting Pb or Pb-Bi as a heat-transfer for nitride U-Pu fuel core cooling. It is anticipating a number of features like, for instance, using of reactor grade plutonium, core breeding ratio ~1, moderate core fuel rating, small reactivity margin, etc.

The features of neutron physics parameters of such type of reactors allow to exclude a production of weapon grade plutonium, effectively use plutonium accumulated during thermal reactors operation, deterministically exclude heavy accidents initiated by any stuff errors and equipment breakdown, to reduce a radiation danger of radioactive wastes.

At the same time the Pb (Pb-Bi) cooled media are of interest from the point of view of accelerator driven systems development since they are considered as a potential prototypes of their blankets.

All these considerations allow to be sure the investigation of such media is promising and have a practical sense. Implementation of experimental benchmarks and calculation codes and neutron physics libraries testing on their basis are, certainly, one of the investigation directions that should be carried out in a various means before any decision is taken for choosing a further way of the above systems development.

The Project has an aim to obtain new information about neutron physics parameters of such kind critical media. It is suggested to implement the work by a detailed analysis of experiments set obtained at BFS fast critical facility of SSC RF-IPPE.

The benchmark experiments proposed are as follows:

BFS-85-1 and -2: the fast systems with U dioxide fuel; their central parts consist of Pb-Bi (-85-1) and Pb (-85-2) rods as well as their reflectors were assembled of Pb-Bi rods.

BFS-87-1 and -2: the fast systems with U-Pu fuel as well as Pb-Bi (-87-1, -87-2) and Pb (-87-2) reflectors. The assemblies were intended for reflectance properties of Pb and Pb-Bi reflectors study.

BFS-95-1 and -2: the fast systems with U-Pu fuel and Pb in the core surrounded with three types of reflectors (lead, uranium dioxide and boron carbide). A central part of BFS-95-1 low enrichment zone was constructed using high radiation plutonium (~11% Pu-240) as well as the one of BFS-95-2 was based on low radiation plutonium (~4% Pu-240). Beside the highly enriched uranium a zone of high enrichment of both assemblies involved a large amount of lead.

The results of the benchmark experiments will be analyzed by modern approaches. As a result they will be useful for reactor physics codes validation with reference to Pb (Pb-Bi) critical media, for Pb and Bi neutron data libraries update, and will be a supplementary contribution to accumulation of experimental and calculation set for Pb (Pb-Bi) cooled media parameters study.