WPNCS Expert Group on Source Convergence

Improper source convergence can lead to non-conservative estimates of the k-effective for various fissionable configurations. These include calculations of the k-effective for the "whitesides problem", spent fuel casks, spent fuel storage pools and fuel processing systems. To improve the robustness of criticality safety analyses with respect to source convergence, the NEA has established an expert group to investigate the long-standing problem of source convergence for certain classes of nuclear criticality safety problems.

Under the guidance of the Working Party on Nuclear Criticality Safety, the major assignments of the expert group include:

• developing criticality safety benchmark problems which exhibit convergence problems;
• testing fission source algorithms for vulnerability to slow convergence;
• developing criteria to measure convergence reliability;
• developing source convergence guidelines for the nuclear criticality safety analysts;
• exploring and evaluating methods to detect source convergence;
• publishing the results.

Benchmark specifications

Related links

NEA Working Party on Nuclear Criticality Safety

Nuclear Science Committee

Working area (password required)

E-mail contact: Yolanda Rugama (rugama@nea.fr)

Last updated: 20 September 2007