Preliminary CEFR analysis by Monte Carlo codes

Abstract

In this paper, the preliminary results of MCS and MCNP6.1 Monte Carlo (MC) codes for a neutronics benchmark China Experimental Fast Reactor (CEFR) start-up test are presented. Monte Carlo neutron/photon transport code MCS which has been under development in the computational reactor physics and experiment laboratory at the Ulsan National Institute of Science and Technology (UNIST) aiming at large scale power reactor simulation. The 2D fuel pin, fuel SAs and 3D core with smeared into coolant, without wire were modeled by MCS and MCNP6.1. Additionally, the 2D fuel pin, fuel SAs and 3D core with spiral wire were modeled by MCS only. The comparison, analysis in 2D and 3D models was conducted. To qualify the MCS Monte Carlo code system as a tool for fast reactor analysis, the results of keff, control rod worth, sodium void, temperature, subassembly swap reactivity have been obtained by MCS and MCNP6.1 codes. The MCS and MCNP6.1 results show good agreement for case with huge variation of keff and it is slightly different for the case with very small variation of keff. In the future, the MCS with spiral wires and MCNP6.1 calculation will be conducted and compared against the actual experimental results. The fission rate, power distribution, delay neutron fraction, foil activation reactivities calculations and uncertainty analysis will be investigated.