A Non-Uniform Leakage Correction Method Applicable to Rod-by-Rod Calculation

Abstract

The invention discloses a non-uniform leakage correction method suitable for bar-by-bar calculation. The method comprises the following steps of 1, performing statistics on lattice cell information, firstly performing high-order transport calculation on non-uniform components, and then performing calculation to obtain uniform cross sections and average neutron flux density of all lattice cells, and net neutron current density and neutron flux density of the surface of each lattice cell in the components; 2, generating a discontinuous factor for a non-uniform leakage correction solving method according to an equivalent uniformization principle, and solving a non-uniform leakage correction model by adopting a longitudinal coordinate discretization method; and 3, correcting neutron flux density distribution by utilizing a critical energy spectrum generated by non-uniform leakage correction, performing re-merging to obtain the uniform cross sections, generating corresponding diffusion coefficients, and multiplying the uniform cross sections and the diffusion coefficients by flux ratios of uniform components and the non-uniform components of the lattice cells. According to the method, an energy spectrum correction factor and a leakage coefficient of each lattice cell can be obtained by utilizing the non-uniform leakage correction model.

Description

technical field [0001] The invention relates to the field of nuclear reactor core design and safety, in particular to a non-uniform leakage correction method suitable for bar-by-rod calculation. Background technique [0002] In order to ensure the safety of reactor core design, it is necessary to accurately calculate the rod power distribution in the reactor for reactor safety analysis. [0003] The reactor is a huge system, and it is very difficult to directly perform one-time neutronics calculations on the entire core. At present, in the core physical design and fuel management calculation, the homogenization method is mainly used, and the inhomogeneous medium in a certain range is replaced by an equivalent homogeneous medium one or more times to gradually simplify and calculate step by step. The traditional PWR physical calculation method is based on two homogenization calculations. Firstly, each type of cell is homogenized, and then various types of cells are combined ...

AI Technical Summary

Problems solved by technology

However, the energy spectrum obtained under the uniform leakage model can be used to match the whole component homogenized to one material, but not to the grid homogenized component

Therefore, in the grid calculation of bar-by-bar calculation, it is impossible to simply use the uniform leakage model for energy spectrum correction

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