Multi-group formulation of the temperature-dependent resonance scattering model and its impact on reactor core parameters

作者：Ghrayeb Shadi Z; Ougouag Abderrafi M^*; Ouisloumen Mohamed; Ivanov Kostadin N

来源：Annals of Nuclear Energy, 2014, 63: 751-762.

DOI：10.1016/j.anucene.2013.07.031

• Resonance scattering
• Multi-group formulation
• Doppler effect
• Up-scattering
• Elastic scattering

A multi-group formulation for the exact neutron elastic scattering kernel is developed. It incorporates the neutron up-scattering effects stemming from lattice atoms thermal motion and it accounts for them within the resulting effective nuclear cross-section data. The effects pertain essentially to resonant scattering off of heavy nuclei. The formulation, implemented into a standalone code, produces effective nuclear scattering data that are then supplied directly into the DRAGON lattice physics code where the effects on Doppler reactivity and neutron flux are demonstrated. The correct accounting for the crystal lattice effects influences the estimated values for the probability of neutron absorption and scattering, which in turn affect the estimation of core reactivity and burnup characteristics. The results show an increase in values of Doppler temperature feedback coefficients up to -10% for UOX and MOX LWR fuels compared to the corresponding values derived using the traditional asymptotic elastic scattering kernel. This paper also summarizes research performed to date on this topic.

• 出版日期2014-1