JAEA-Conf 2011-002 - 日本原子力研究開発機構

JAEA-Conf 2011-002
32. Effect of Newly-Measured Cross Sections of 157Gd on Burnup Characteristics of
High Burnup BWR UO2 and MOX Assemblies
Yoshihira ANDO 1,*, Toru YAMAMOTO 1 and Peng Hong LIEM 2
1 Reactor Core and Fuel Reliability Group, Safety Standard Division
Japan Nuclear Energy Safety Organization (JNES)
TOKYU REIT Toranomon Bldg. 7F, 3-17-1, Toranomon,
Minato-ku, Tokyo 105-0001, Japan
2 Nippon Advanced Information Service Corporation
Muramatsu 416, Tokai-mura Naga-gun Ibaraki-ken-1112, Japan
* E-Mail:ando-yoshihira@jnes.go.jp
Effect of newly-measured cross sections of 157Gd by Leinweber et al. (2006) on burnup
characteristics of high burnup BWR UO2 and MOX assemblies was investigated by coupling
burnup calculation using SRAC code with a modified JENDL-3.3 nuclear data library
reflecting the above newly measured data. It was confirmed that meaningful differences on
multiplication factors and fission distributions in the assemblies were observed mainly below
15GWd/t.
1 Introduction
Leinweber et al.[1] have reported new measurement data on neutron capture, total
cross sections and resonance parameters of Gd isotopes. One of the prominent results was
that the thermal (2200m/s) capture cross section of 157Gd was 11% smaller compared with
that in ENDF/B-VI.8[2]. Jatuffa et al.[3] have tested the newly-measured Gd isotope cross
sections in the analysis of measured fission reaction rates of Gd2O3-UO2 rods (Gd rods) in
tested BWR UO2 fuel assemblies in core physics experiments and reported that the new cross
sections improved the discrepancy of the theoretically analyzed results from the
measurements.
During the evaluation study of JENDL-4 [4], the adoption of the new measurement
data was assessed. For this purpose a preliminary cross section library for a continuous
energy Monte Carlo calculation code MVP[5] was prepared to test the new data of 157Gd in the