Leakage-Corrected Discontinuity Factors for PHWR Lattices - A Simple Test

Abstract

Due to the heterogeneity present in the core, solving for the flux in the full core is not practical without applying homogenization. Theoretically, by using exact discontinuity factors and node-homogenized cross sections, the node flux and power for the node-homogenized core equal the ones of the heterogeneous core. However, exact node homogenized parameters can only be obtained if exact heterogeneous node boundary conditions are known but, of course, exact node boundary conditions are determined by the full-core heterogeneous flux which is not known a priori for any real practical case. However, near-exact node-boundary conditions can be obtained by performing global-local iterations between lattice and core calculations, a process known as leakage correction.Leakage-corrected discontinuity factors and homogenized cross sections have shown very good gain in accuracy for PT-SCWRs. This work investigates the application of leakage-corrected cross-sections and discontinuity factors via global-local iterations to a simple, one-dimensional, model consisting of several PHWR-type nodes.