The precise calculation of reactor pressure vessel (RPV) fast neutron fluence can be used to evaluate the materials irradiation damage during the designed lifetime and support analyses for a potential plant life extension. The uncertainties of reactor materials and geometry
nuclear data
neutron source and transport solving process can affect the reliability of fast neutron fluence simulation results.
Purpose
2
This paper aims to effectively evaluate the calculation results by thorough analysis of the uncertainties described above.
Methods
2
This paper analyzed the main origin of uncertainties in the RPV fast neutron fluence calculation and focus on the effect of the neutron source processing method
the Legendre expansion of the anisotropic scattering cross section and spatial discretization method of transport equation.
Results and Conclusion
2
Modeling of fuel assemblies usually produces a deviation about 20%
the effect of fission nuclide and transport correction methods are about 10%. Through analyses we can understand the weak aspects of the calculation methods and improve the accuracy of calculation results.
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references
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