Proceedings of ICAPP 2014, Charlotte, NC, USA, April 6-9, 2014, on CD-ROM (2014)
A control rod decusping scheme for direct whole core transport calculations involving partial control rod insertion was developed by employing precalculated axial flux profiles obtained for various partial insertion configurations and intrapellet fluxes. Each axial flux profile are obtained by solving a local 3-D coarse mesh finite difference (CMFD) with a partially rodded node. 2-D MOC solutions for the rodded and unrodded assemblies are also used to incorporate the significant spatial self-shielding effect within the control rod. The accuracy and performance of the proposed decusping scheme is verified by applying the method to a 3x3 assembly problem and then to a real pressurized water reactor core problem. It is confirmed that the proposed treatment can accomplish efficient yet effective decusping in the whole core transport calculation for the power reactors.
