Ricerc@Sapienza

The divertor is the most solicited one of the plasma facing components (PFCs), which are the components of a nuclear fusion reactor that constitute the boundary between the fusion plasma and the rest of the device. To withstand the extreme heat loads incoming from the plasma, liquid metals (LM) are considered as armor in some PFCs concepts either as a flowing film, a curtain of droplets (liquid wall), or imbibed in a porous medium. LM breeders are also considered in the design of the breeding blanket (BB), where neutron capture reactions generate tritium, fuel for the machine, and helium as byproduct. The necessity to account for the interaction between the electrically conductive LM and the magnetic field employed to confine the plasma, the magnetohydrodynamic phenomena (MHD), is one of the most challenging engineering issues in the LM application for fusion. Computational fluid dynamics (CFD) is a valid alternative to experimental analysis for complex and expensive systems such as PFCs and BBs. Among the CFD codes, OpenFOAM is a very promising opensource code as it allows a deep customization of the models, providing an ideal and almost indispensable environment for computational MHD (CMHD). The aim of this project is the development of an OpenFOAM MHD solver capable of simulating a multi-phase mixture with a high-density ratio between the phases, a numerically challenging task even for an ordinary mixture. Such a solver would allow a detailed analysis of multiphase flow in LM PFCs and BBs that are currently under development in the framework of the roadmap towards fusion electricity proposed by EUROfusion, the European consortium for the development of nuclear fusion, and will ultimately be tested in the ITER and DEMO reactors.