| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 297056 | Nuclear Engineering and Design | 2012 | 8 Pages |
Neutronic characteristics were investigated for a once-through-then-out (OTTO) refueling scheme based on the 400 MWt pebble bed modular reactor (PBMR) and compared with that of a reference multi-pass scheme. The core was loaded with new fuel pebbles which were designed with Gd2O3 particles to flatten the axial power profile. The Gd2O3 design was considered in a multi-parameter optimization to maximize the average discharged burnup while maintaining a limited power peak and ensuring core criticality. The results show that the OTTO scheme using the new fuel pebbles can achieve the maximum average discharged burnup of about 75 GWd/t, at which the core neutronic characteristics are comparable with that of the reference multi-pass scheme. This means that the efficiency of fuel utilization of the OTTO scheme is about 21% less than that of the multi-pass scheme (95 GWd/t).
► Neutronic characteristics were analyzed for an OTTO refueling PBMR. ► The core uses newly designed fuel pebbles with Gd2O3 as burnable poison. ► The neutronic characteristics are comparable with a reference multi-pass scheme. ► The average discharged burnup is 21% lower than that of the multi-pass scheme.
