Spatially Dependent Resonance Cross Sections in a Fuel Plate

The classical resonance absorption theory known as equivalence theorem which treats two-region problem (Fuel/Moderator) has been generalized to arbitrary sub regions of fuel pin by Stoker/Weiss technique and SDDM (Spatially Dependent Dancoff Method). Stoker/Weiss technique and SDDM were derived only for infinite cylinders. To calculate the shielded resonance cross sections for sub regions in the fuel plate, a method is presented by geometrical derivation of first flight blackness for slab geometry. To validate the method, probability approximation and cross section generation are all compared to the benchmark problems. It is concluded that this method is practically useful and appropriate for generating the effective cross-sections in sub regions of a fuel plate.