RT Conference Proceedings
SR 00
A1 Herrero Carrascosa, José Javier
A1 García Herranz, Nuria
A1 Ahnert Iglesias, Carolina
T1 A proposed parameterization of interface discontinuity factors depending on neighborhood for pin-by-pin diffusion computations for LWR
YR 2011
FD 08/05/2011 - 12/05/2011
AB There exists an interest in performing full core pin-by-pin computations for present nuclear reactors. In such type of problems the use of a transport approximation like the diffusion equation requires the introduction of correction parameters. Interface discontinuity factors can improve the diffusion solution to nearly reproduce a transport solution. Nevertheless, calculating accurate pin-by-pin IDF requires the knowledge of the heterogeneous neutron flux distribution, which depends on the boundary conditions of the pin-cell as well as the local variables along the nuclear reactor operation. As a consequence, it is impractical to compute them for each possible configuration. An alternative to generate accurate pin-by-pin interface discontinuity factors is to calculate reference values using zero-net-current boundary conditions and to synthesize afterwards their dependencies on the main neighborhood variables. In such way the factors can be accurately computed during fine-mesh diffusion calculations by correcting the reference values as a function of the actual environment of the pin-cell in the core. In this paper we propose a parameterization of the pin-by-pin interface discontinuity factors allowing the implementation of a cross sections library able to treat the neighborhood effect. First results are presented for typical PWR configurations.
T2 International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2011
ED Rio de Janeiro, Brasil
AV Published
LK http://oa.upm.es/11961/