Simulation of a metal Zr:U Cruciform CANDU-6 fuel element

A modified CANDU-6 fuel bundle consisting of a helical, cruciform uranium-zirconium metal alloy has been investigated in order to achieve a bundle power higher than 725 kW. The neutronics, burnup, and temperature of this fuel has been simulated at the usual melting point of conventional UO 2 fuel pellets (a bundle power of 1270 kW). An iterative process is used to simulate the neutronics in MCNP4 and perform burnup and thermalhydraulics calculations in MATLAB. The 70at% zirconium fuel at natural enrichment did not remain critical beyond a burnup of 0.064 MWd·kgU-1. However, fuel with an enrichment of 1% is shown to have a homogenous discharge burnup of 10.03 MWd·kgU-1 and a power density of 165.5 kW·kgU-1. The potential for increasing the bundle power further is examined. In addition, fuel cycle synergies with light water reactors are discussed.