KENO-IV code benchmark calculation, (9)

A series of benchmark tests has been undertaken in JAERI in order to examine the capability of JAERI's criticality safety evaluation system consisting of the Monte Carlo calculation code KENO-IV and the newly developed multi-group constants library MGCL. The present report describes the results of a test using criticality experiments about three clusters of UO2 rods lattice in water tank. A total of the 48 criticality cases has been calculated for the UO2 rods lattice being arrayed in three clusters as well as in a single cluster, with and without poison plates in water gap between the clusters. For these 48 cases in variety, the effective multiplication factors are predicted as 0.9902 in average, being normally distributed in a small standard deviation 0.0028. This sharp spectrum of results shows good reliability of the calculation by KENO-IV and 26-energy group MGCL for LWR fuel assemblies storaged in a pool. (author)