A New Equivalence theory Method for Treating Doubly Heterogeneous Fuel? II: Verifications
|dc.contributor.author||Williams, Mark L.||ko|
|dc.identifier.citation||NUCLEAR SCIENCE AND ENGINEERING, v.180, no.1, pp.41 - 57||ko|
|dc.description.abstract||A new methodology has been developed recently to treat resonance self-shielding in systems for which the fuel compact region of a reactor lattice consists of small fuel grains dispersed in a graphite matrix. The theoretical development adopts equivalence theory in both micro- and macro-level heterogeneities to provide approximate analytical expressions for the shielded cross sections, which may be interpolated from a table of resonance integrals or Bondarenko factors using a modified background cross section as the interpolation parameter. This paper describes the first implementation of the theoretical equations in a reactor analysis code. To reduce discrepancies caused by use of the rational approximation for collision probabilities in the original derivation, a new formulation for a doubly heterogeneous Bell factor is developed in this paper to improve the accuracy of doubly heterogeneous expressions. The methodology is applied to a wide range of pin cell and assembly test problems with varying geometry parameters, material compositions, and temperatures, and the results are compared with continuous-energy Monte Carlo simulations to establish the accuracy and range of applicability of the new approach. It is shown that the new doubly heterogeneous self-shielding method including the Bell factor correction gives good agreement with reference Monte Carlo results.||ko|
|dc.publisher||AMER NUCLEAR SOC||ko|
|dc.title||A New Equivalence theory Method for Treating Doubly Heterogeneous Fuel? II: Verifications||ko|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.