Benchmarking of OpenMC on OPAL research reactor

  Ben Hatzofe  ,  Nir Kastin  ,  Chen Dubi  
Israeli atomic energy commission

Benchmarking of OpenMC on OPAL research reactor
B. Hazofe1, C. Dubi2,3, N. Kastin1
1Israel Atomic Energy Commission
2Physics Dep. Nuclear Research Center Negev, Beer Sheva, Israel, P.O.B 9001
3Dep. Of Mathematics, Ben-Gurion University of the Negev
Australia’s Open Pool Australian Lightwater (OPAL) reactor is a state-of-the-art 20 megawatt multi-purpose reactor that uses low enriched uranium (LEU) fuel to achieve a range of activities to benefit human health, enable research to support a more sustainable environment and provide innovative solutions for industry. Opened by the Prime Minister in 2007, OPAL is one of a small number of reactors with the capacity to produce commercial quantities of radioisotopes. This capacity, combined with the open pool design, the use of low enriched uranium fuel and the wide range of applications, places OPAL amongst the best research reactors in the world.
Moreover, due to its modern design and state-of-the-art operational data documentation, the OPAL reactor may serve as a reliable benchmark for open-pool LEU research reactors. Taking into account the comprehensive attention which is given to throughout IAEA CRP forums, accompanied by a significant amount of computational benchmarks and contributions worldwide, the OPAL reactor may serve as a fantastic benchmark for both verification and validation processes of codes.
In this work, the OPAL reactor has been thoroughly modeled using OpenMC, a community-developed Monte Carlo neutron and photon transport simulation code, which supports both continuous-energy and multi-group transport. It is capable of performing fixed source, k-eigenvalue, and subcritical multiplication calculations on models built using either a constructive solid geometry or CAD representation. Parallelism of computations is enabled via a hybrid MPI and OpenMP programming model.
Benchmarks are given in this work for various experimental results which were obtained for core #7 of the OPAL reactor. The model for the core, which was constructed using OpenMC code, contains the full modeling of core #7, to it's various components including the outer core region. It also includes the modelling of the 3 types of LEU MTR fuel cells, which consist of various material compositions and geometry structure (BP included or not). Results are given for all critical states experiments, FSS rods’ reactivity worth and flux distribution obtained through gold wires irradiation analysis.