PHISICS: New Features and Advancements

The PHISICS (Parallel and Highly Innovative Simulation for INL Code System) software is under an intensive development at INL. In the last months new features have been added and improvements of the previously existing one performed. The modular approach has created a friendly development environment that allows a quick expansion of the capabilities. In the last months a little amount of work has been dedicated to the improvement of the spherical harmonics based nodal transport solver while the implementation of a solver based on the self adjoint formulation of the discrete ordinate is in the test phase on structured mesh. PHISICS now include a depletion solver with the option to use two different algorithms for the solution of the Bateman equation: the Taylor development of the exponential matrix and the Chebyshev Rational Approximation Method. The coupling with RELAP5 is also available at least in the steady state search mode. The coupling between RELAP5 and PHISICS can also take advantage of the new cross section interpolation module so that the coupling could be performed using an arbitrary number of energy groups.