Patent ID: 7428479

Claim:
A method for computer modeling the core of a nuclear reactor, comprising the following method steps: dividing the core into a multiplicity of coarse mesh cells including at least one given coarse mesh cell and adjoining coarse mesh cells; assigning the at least one given coarse mesh cell a subregion of the core, the subregion having a boundary and containing the given coarse mesh cell and a buffer zone, the buffer zone enclosing the given coarse mesh cell in a horizontal direction and containing at least the coarse mesh cells immediately adjoining the coarse mesh cell; dividing the subregion into a multiplicity of fine mesh cells, the fine mesh cells being finer than the coarse mesh cells; assigning a first dataset to each coarse mesh cell and, based on the dataset respectively assigned to each coarse mesh cell, calculating a model of the core, including fluxes at the boundary of the subregion by a nodal calculation method in a first computation step; assigning a second dataset to each fine mesh cell and, based on the second dataset respectively assigned to each fine mesh cell of a subregion and with fluxes at the boundary of the subregion as calculated in the first computation step, calculating a model for the subregion by a nodal calculation method in a second computation step; and outputting the model of the core obtained in the first computation step and the model for the subregion obtained in the second computation step.