Exploring liquid metal PFC concepts: Dynamics of fast flowing lithium films under fusion relevant magnetic fields

The use of fast flowing lithium streams for protection of the divertor surface in a magnetic fusion device is a very attractive option for effective particle pumping and surface heat removal. The divertor magnetic field environment tends to create strong flow disrupting magnetohydrodynamic (MHD) forces, which pose a major challenge in establishing a smooth and controllable flow. In this paper the 3D incompressible, multi-material MHD free surface code, HIMAG, developed by HyPerComp Inc. in collaboration with UCLA has been applied to model several problems of interest which are pivotal in understanding the basic MHD behavior of fast flowing lithium streams on rectangular electrically conducting substrates. The parameters used in the numerical studies conform to the outboard divertor region of the NSTX machine at Princeton