TY - JOUR

T1 - Utilizing neutronics modelling to predict changing Pu ratios in UO2 in the presence of Th

AU - Evitts, Lee

AU - Gilbert, M. R.

AU - Middleburgh, Simon

AU - Lee, Bill

AU - Dahlfors, Marcus

N1 - REF 100 words: MW to add to REF module when accepted for publication Part of an ongoing collaboration between AWE and the £6M Nuclear Futures Institute (Welsh Government and WEFO funded) project, the field of nuclear forensics is advanced in a regime where real data is lacking through the application of high-resolution continuous-energy neutronics simulations. AWE has asked for further studies and an invited conference talk has resulted. The development of these techniques combined with thermal hydraulics studies was key to securing the new collaborative user facility at Bangor University, THOR (£340k from Ser Cymru), as well as for the formation of the £2M EPSRC bid for an upgraded facility, THUNDER.

PY - 2021/7/1

Y1 - 2021/7/1

N2 - The isotopic fractions of plutonium produced in a reactor are of significant value as nuclear forensic signatures, and the mechanisms of their production and alteration should be investigated thoroughly. A series of neutronics calculations were made on a typical UO2 PWR setup, introducing (Th, U)O2 MOX rods gradually, to investigate how the presence of Th affects the 240Pu/239Pu and 242Pu/239Pu ratios in the remaining UO2 fuel rods. A relationship is found that links the percentage change in these ratios, with the burnup and Th content in the configuration. In an extreme case, it was found that the presence of Th may increase the ratio of 242Pu/239Pu by as much as 3.5% at low burnup.

AB - The isotopic fractions of plutonium produced in a reactor are of significant value as nuclear forensic signatures, and the mechanisms of their production and alteration should be investigated thoroughly. A series of neutronics calculations were made on a typical UO2 PWR setup, introducing (Th, U)O2 MOX rods gradually, to investigate how the presence of Th affects the 240Pu/239Pu and 242Pu/239Pu ratios in the remaining UO2 fuel rods. A relationship is found that links the percentage change in these ratios, with the burnup and Th content in the configuration. In an extreme case, it was found that the presence of Th may increase the ratio of 242Pu/239Pu by as much as 3.5% at low burnup.

U2 - 10.1016/j.pnucene.2021.103762

DO - 10.1016/j.pnucene.2021.103762

M3 - Article

VL - 137

JO - Progress in Nuclear Energy

JF - Progress in Nuclear Energy

SN - 0149-1970

M1 - 103762

ER -