A comparative study on the safety and kinetic parameters of UO2 and MOX fuel

Abstract EN

A pin cell model is used to study and compare the safety and kinetic parameters of UO2 and MOX fuels, when used in a PWR.

The studied fuels are UO2 of 3.9% and 5% enrichment, and mixed uranium plutonium from reactor recycle and weapon grade sources each with two PuO2 contents, 4% and 6%.

The safety parameters studied are the Doppler coefficient, the moderator temperature coefficient, and the soluble boron worth.

The results showed that the MOX fuel with reactor grade plutonium has the highest Doppler and moderator temperature coefficients, while UO2 has the highest boron worth.

Burnup calculations were performed to study the change in the multiplication factor, the effective delayed neutron fraction, and the neutron mean generation time.

The reactivity of UO2 showed larger decrease with burn up than both types of MOX fuel.

The delayed neutron fraction for UO2 decreased with burnup, while it increased for MOX fuel.

The neutron generation time increased generally with burnup, with the highest values for UO2.

The results are in agreement with previous studies