Fluoride Salt-Cooled High-Temperature Reactor (FHR) Benchmark

Fluoride salt-cooled high-temperature reactors (FHRs), cooled with liquid (molten) salt, fuelled with TRISO-based fuel are a potential molten salt reactor (MSR) design.

Such reactor designs share certain similarities (heat removal by molten salt) with the historic molten salt reactor experiment (MSRE), but also present a fundamental difference in having solid fuel, either in the form of circulating pebbles or in hexagonal fuel elements. The complex fuel geometry and novel materials challenge existing simulation tools. At the same time, there are no experimentally-obtained results making cross-verification using different reactor physics codes and methods a suitable approach to verify performance and identify gaps in simulation capability.

The purpose of this benchmark is to:

  • provide data on the neutronics codes ability to predict core multiplication factor (k-eff)
  • provide data on reactivity coefficient simulation capabilities
  • provide data on burnup prediction capabilities
  • provide data on fission density prediction capabilities
  • provide information on the neutronics codes ability to model/simulate complex geometry
  • provide feedback on nuclear data libraries performance for MSR systems
Publications and reports

The benchmark proposal was accepted at the 2019 Expert Group on Reactor Physics and Advanced Nuclear Systems (EGRPANS) meeting.


Phase I-A: Fresh Fuel Element 2-D Analysis without Depletion (July 2019 - April 2020)

  • Case 1A: Reference Hot Full Power (HFP)
  • Case 2A-H: Hot Zero Power (HZP)
  • Case 2A-C: Cold Zero Power (CZP)
  • Case 3A: HFP Control Rod Worth
  • Case 4A: HFP Discrete Europia Burnable Poison
  • Case 5A: HFP Integral Europia Burnable Poison
  • Case 6A: HFP Increased TRISO Density
  • Case 7A: HFP Increased Enrichment

Phase I-B: Depletion Analysis

  • Case 1B: Case 1A with Depletion
  • Case 4B: Case 4A with Depletion
  • Case 7B: Case 7A with Depletion

Phase II: 3-D Full Core Model

Phase III: 3-D Full Core Model with Feedback

Members' area

Details, including specifications and results templates can be found in the working area. To access the working area, please fill out the conditions form and e-mail it to wprs@oecd-nea.org.

FHR Benchmark (requires password | reminder)


Ian Hill, NEA

Bojan Petrovic, Co-ordinator, Georgia Institute of Technology: