Improved coarse-mesh method for neutron diffusion calculations in hexagonal-z geometry

摘要

A high-order nodal method of correctining the conventional coarse-mesh group diffusion equations in hexagonal-z geome- try is presented. correction coefficients modify the coarse- mesh fluxes and diffusion coefficients in the leakage terms of the neutron balance equations. The analytical expressions for the correction coefficients are derived by consideration of the local balance diffusion equation in the sub-node of the coarse- mesh hexagonal node.