PWR INTEGRAL GADOLINIA BURNABLE ABSORBER LOADING DESIGN IN A ONCE-THROUGH CORE REACTIVITY SWING MINIMIZATION ASSESSMENT

摘要

The PWR-193 1/8~th core MCNP Pin-by-Pin model was successfully used to evaluate once-through burnup cycles with varying UGdO-56 options. The developed MCOS BASH script provided accurate and stable fuel burnup calculations for the depleted fissionable materials and BA U vs. depletion time. The results of the MCOS calculations also demonstrate the BA UGdO can effectively hold down the initial excess reactivity from 1.423 to 1.062. The results show the stability of MCOS algorithm provides an accurate BA UGdO loading pattern performance assessment. In addition, the Monte Carlo burnup script - MCOS using the continuous neutron cross library updated the nuclide resonance effect very well from depletion time-step to time-step on the fly.