A unified generic theory on discontinuity factors in diffusion, SP3 and transport calculations

The theory has been tested to work well on a series of mini-core benchmark problems with severe heterogeneity. The tests are made for the Method of Characteristics (MOC) transport calculation, the SP3 calculation and the diffusion calculation. Both pin-cell homogenization and assembly homogenization cases are covered in the tests. Comparison is made on the results using the Prime EPDF, the Renormalized EPDF, the conventional discontinuity factor and the SPH (super homogenization) factor. Generally speaking, for cases with homogenized pin cells the Prime EPDF gives the best accuracy while for cases with homogenized assemblies the Renormalized EPDF gives the best accuracy.