Atucha-2 is a Siemens-designed PHWR reactor in phase of commissioning in the Republic of Argentina. Its geometrical complexity and peculiarity (e.g., oblique control rods, positive void coefficient) required a developed and validated complex three dimensional (3D) neutron kinetics (NK) model. In the framework of the agreement between NA-SA and University of Pisa a detailed NES-TLE (threedimensional neutron kinetics code) model of the Atucha-2 NPP was developed. This document summarizes the procedures for the implementation of the oblique control rods into the RELAP5/ NESTLE model: a particular arrangement of RELAP5/NESTLE control rods insertion mode for such kind of oblique control rods and an implementation into the homogenized two group cross sections of adhoc calculated correction factors (these parameters were obtained by previously executed Monte Carlo calculations) was developed. Some applications, among the scenarios selected to perform safety analysis of the Atucha-2 NPP (CNA-II), are also reported: preliminary Scram Rod Worth, analysis of a Control Rod Ejection Accidents and a CR faulty withdrawal.
Atucha-2 Obliquely Inserted Control Rods RELAP5-3D/NESTLE Model
D’Auria F.Software
;
2014-01-01
Abstract
Atucha-2 is a Siemens-designed PHWR reactor in phase of commissioning in the Republic of Argentina. Its geometrical complexity and peculiarity (e.g., oblique control rods, positive void coefficient) required a developed and validated complex three dimensional (3D) neutron kinetics (NK) model. In the framework of the agreement between NA-SA and University of Pisa a detailed NES-TLE (threedimensional neutron kinetics code) model of the Atucha-2 NPP was developed. This document summarizes the procedures for the implementation of the oblique control rods into the RELAP5/ NESTLE model: a particular arrangement of RELAP5/NESTLE control rods insertion mode for such kind of oblique control rods and an implementation into the homogenized two group cross sections of adhoc calculated correction factors (these parameters were obtained by previously executed Monte Carlo calculations) was developed. Some applications, among the scenarios selected to perform safety analysis of the Atucha-2 NPP (CNA-II), are also reported: preliminary Scram Rod Worth, analysis of a Control Rod Ejection Accidents and a CR faulty withdrawal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
