An Innovative Reactor Analysis Methodology Based on a Quasidiffusion Nodal Core Model. Nuclear Energy Research Initiative (NERI) Program. Quarterly Technical Progress Report, July 1 - September 30, 2000

Abstract

Status Summary of Nuclear Energy Research Initiative (NERI) Tasks: Task 1--The development of the following methods in ID slab geometry: (1) Homogenization and definition of discontinuity factors, (2) Group constants functionalization using assembly transport solution of multigroup eigenvalue problem with albedo boundary conditions, and (3) Solving coarse-mesh effective few-group 1D QD moment equations using tables of data parametrized with respect to the ratio {rvec n} {center_dot} {rvec {tilde J}{sup G}}/{tilde {phi}{sup G}} on boundaries. Task 2--Development of a numerical method for solving the 2D few-group moment QD equations: (1) Development of a nodal discretization method for 2D moment QD equations, and (2) Development of an efficient iteration method for solving the system of equations of the nodal discretization method for 2D moment QD equations. Task 3--The development of the following methods in 2D X-Y geometry: (1) homogenization and definition of discontinuity factors, (2) group constants functionalization using assembly transport solution of multigroup eigenvalue problem with albedo boundary conditions, and (3) solving coarse-mesh effective few-group QD moment equations using tables of data parametrized with respect to the ratio {rvec n} {center_dot} {rvec {tilde J}{sup G}}/{tilde {phi}{sup G}} on boundaries. Task 4--Development of a numerical method for solving the few-group moment QD equations in 3D geometry: (1) Development of a nodal method for discretization of 3D moment QD equations, and (2) Development of an efficient iteration method for solving the system of nodal discretized equations of moment QD equations in 3D geometry.