Accelerator-driven sub-critical research facility with low-enriched fuel in lead matrix - neutron flux calculation

The H5B is a concept of an accelerator-driven sub-critical research facility (ADSRF) being developed over the last couple of years at the Vinca Institute of Nuclear Sciences, Belgrade, Serbia. Using well-known computer codes, the MCNPX and MCNP, this paper deals with the results of a target study and neutron flux calculations in the subcritical core. The neutron source is generated by an interaction of a proton or deuteron beam with the tar get placed in side the subcritical core. The results of the total neutron flux density escaping the target and calculations of neutron yields for different target materials are also given here. Neutrons escaping the target volume with the group spectra (first step) are used to specify a neutron source for further numerical simulations of the neutron flux density in the sub-critical core (second step). The results of the calculations of the neutron effective multiplication factor keff and neutron generation time L for the ADSRF model have also been presented. Neutron spectra calculations for an ADSRF with an uranium target (highest values of the neutron yield) for the selected sub-critical core cells for both beams have also been presented in this paper. (author)