Transport Corrections in Nodal Diffusion Codes for HTR Modeling

Technical Report · Sun Aug 01 04:00:00 EDT 2010

DOI:https://doi.org/10.2172/993162· OSTI ID:993162

Ougouag, Abderrafi M; Gleicher, Frederick N

The cores and reflectors of High Temperature Reactors (HTRs) of the Next Generation Nuclear Plant (NGNP) type are dominantly diffusive media from the point of view of behavior of the neutrons and their migration between the various structures of the reactor. This means that neutron diffusion theory is sufficient for modeling most features of such reactors and transport theory may not be needed for most applications. Of course, the above statement assumes the availability of homogenized diffusion theory data. The statement is true for most situations but not all. Two features of NGNP-type HTRs require that the diffusion theory-based solution be corrected for local transport effects. These two cases are the treatment of burnable poisons (BP) in the case of the prismatic block reactors and, for both pebble bed reactor (PBR) and prismatic block reactor (PMR) designs, that of control rods (CR) embedded in non-multiplying regions near the interface between fueled zones and said non-multiplying zones. The need for transport correction arises because diffusion theory-based solutions appear not to provide sufficient fidelity in these situations.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - NE
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 993162
• Report Number(s): INL/EXT-10-19729
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
AVAILABILITY
BURNABLE POISONS
CONTROL ELEMENTS
DIFFUSION
HTRs
NEUTRONS
NGNP
PEBBLE BED REACTORS
SIMULATION
TRANSPORT
TRANSPORT THEORY
nodal codes