Multi-Dimensional Shield Performance Analysis Through an Even Parity Based “Contributon” Transport Concept

In this paper we present an even parity approach for deriving the detector response flux. Forward and adjoint angular fluxes, ψ(r,Ω) and ψ^†(r,Ω) obtained from the K⁺[ψ⁺] and K^†+[ψ^†+] variational principles are used to determine the spatial channels in shielding materials. These spatial channels clearly show the dose rate passages from the source to the detecting point, hence weak and strong points of the shielding design is illustrated thereafter. Spatial and angular components of the fluxes are approximated using the finite element method (FEM) as well as the spherical harmonics polynomials (SHP), respectively. By the adjoint weighted even parity flux, we can obtain the multigroup response fluxes over arbitrary shaped multidimensional geometries with less computational efforts compared to full parity approaches. A number of test are examined via the code ENTRANS, developed for Even parity Neutron TRANSport calculations. Results confirm ability and robustness of the proposed approach.