Development of an iterative diffusion-transport method based on MICROX-2 cross section libraries

• Published in: Annals of nuclear energy Vol. 77; pp. 335 - 342
• Main Authors: Hou, J., Choi, H., Ivanov, K.N.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-03-2015
• Subjects: 2-D lattice calculation; Benchmarking; Boundary condition; Cross section generation; Cross sections; Cross sections (physics); Diffusion; Homogenizing; Iterative Diffusion-Transport method; Iterative methods; Light water reactors; Mathematical analysis; Reactor cores; Iterative Diffusion-Transport method; 2-D lattice calculation; Boundary condition; Cross section generation
• ISSN: 0306-4549; 1873-2100
• DOI: 10.1016/j.anucene.2014.11.014

•Innovative Iterative Diffusion Transport (IDT) method is developed.•A 2-dimensional (2-D) pin-by-pin lattice program, NEMA, is also developed.•The developed methods and codes are verified on benchmark problems.•Results show that the IDT method improves the global and local predictions.
This paper introduces an innovative online cross section generation method, developed based on Iterative Diffusion-Transport (IDT) calculation to minimize the inconsistency and inaccuracy in determining physics parameters by feeding actual reactor core conditions into the cross section generation process. A two-dimensional (2-D) pin-by-pin lattice program, NEMA, was developed to generate assembly lattice parameters using the refined MICROX-2 cross section libraries and Nodal Expansion Method (NEM). The proposed method was verified against a 2-D miniature core (mini-core) benchmark problem. First, the few-group cross sections generated by NEMA were compared with those calculated by a Monte Carlo method code Serpent. Next, the analysis of a 2-D Light Water Reactor (LWR) mini-core benchmark problem was carried out by the nodal transport code DIF3D using few-group cross sections generated by NEMA, and the results were compared with those obtained from the Serpent full core calculation. Finally, the same benchmark problem was solved by the NEMA-DIF3D approach using the IDT coupling method. The computational benchmark calculations have shown that the homogenization technique implemented in NEMA is reliable when producing the few-group cross sections for the reactor core calculation. The IDT method also improves the eigenvalue and power distribution predictions.