A Multi-scale Approach for the Neutronic Kinetics Equations Using the Mixed Dual Solver Minos

In order to improve the time/precision ratio of the simulation calculations, we investigate a multi-scale technique for the resolution of the reactor kinetics equations. We choose to focus on the mixed dual diffusion approximation and the Quasi-Static method. We introduce a space dependency for the amplitude function which only depends on the time variable in the standard Quasi-Static context. With this new factorization, we develop two mixed dual problems which can be solved with CEA’s solver MINOS. An algorithm is implemented, performing the resolution of these problems defined on different scales (for time and space). We name this approach the Local Quasi-Static method. The consistency of the model and the pertinence of our first modeling and discretization choices are studied for a simplified test. The first results are incomplete but satisfactory. Furthermore, they open new possibilities on parallelization and adaptive scales.