FHR Steady-State Model

Contact: Guillaume Giudicelli, guillaume.giudicelli.at.inl.gov

Model link: FHR Steady-State Multiphysics Model

These input files may be used to perform a coupled multiphysics steady state simulation of the Mk1-FHR. Each physics is solved by the relevant MOOSE application: the neutronics by Griffin, the thermal hydraulics by Pronghorn and the fuel performance by the combined usage of Pronghorn and the MOOSE heat conduction module. A combined application, Direwolf (all users) or BlueCRAB (NRC only), is currently necessary to run the multiphysics coupled problem.

The physics coupling is performed using the MultiApp system. In MOOSE vocabulary, the neutronics application is the main application, the thermal hydraulics and heat conduction are sub-apps. The coupling scheme is shown in Figure 1. Applications are run successively with Picard fixed-point iterations to converge the multiphysics problem. They are said to be tightly coupled, as opposed to loose coupling if the scheme was not iterated, and fully-coupled if a single calculation/matrix was used to solve the multiphysics problem.

Figure 1: Current multiphysics computation scheme for the Mk1-FHR model steady state model

Results for the steady state solution are shown here.