Comparison of McMaster Nuclear Reactor Irradiation Experiments with Simulation

Abstract

A detailed series of irradiation experiments were conducted in the McMaster Nuclear Reactor (MNR), a 2 MW1h, light-water moderated, pool-type research reactor, between March 1997 and January 1999. Standard radioactivation techniques were used to determine the experimental reaction rates of combinations of eight nuclear reactions in seven different core configurations. The reactions used in this study were: 55Mn(n,y)56Mn, 58Fe(n,y)59Fe, 59Co(n,y)60Co, 63Cu(n,y)64Cu, 115In(n,y)116In, 197Au(n,y)198Au, 27Al(n,a)24Na, and 115In(n,n')In. The irradiations were performed in the Central Irradiation Facility (CIF), the in-core 1251 production sites and the graphite reflector, and included both unshielded and Cd-shielded cases. For the iodine and graphite sites, axial maps of 59Co(n,y) and 27Al(n,a) reaction rates were experimentally determined for three core configurations. Reaction rates were compared to calculated values produced from simulation using the WIMS-AECL/3DDT code package. In addition, a neutron flux spectrum unfolding code, SAND-11, was used to generate flux spectra from the experimental results for comparison with the WIMS-AECL/3DDT flux spectra. Good agreement between experimental and calculated results were found in the majority of the Col Al wire cases. The suitability of different foil materials and methodologies are identified.