Validating results from the Molten Salt Reactor Experiment by use of turbulent CFD simulations : A study of a modified U-tube shell-and-tube primary heat exchanger and radiator with molten salts

Sammanfattning: Background Nuclear reactors utilizing molten fuels rather than solid fuels show a massive advantage in energy yield, waste handling and safety features. The only successful reactor utilizing a molten fuel was called the ‘Molten Salt Reactor Experiment’ (MSRE), built and operated in the Oak Ridge national laboratory (ORNL) in Tennessee, U.S.A. during the 1960s. The molten salts in question are fluoride compounds under the name of “FLiBe”. In this thesis, the heat exchangers of the MSRE are modelled and simulated, with the aim to test whether current computational fluid dynamics (CFD) software and mathematical models can accurately predict molten salt heat transfer behaviour.  Methods All programs used are open-source and/or free-access to facilitate open collaboration between researchers in this growing field. All models and findings produced in this thesis are free to use for future research. The program Onshape was used to draw CAD-models based on hand-drawn technical documents released by ORNL. Several programs, e.g., Simscale and Salome, were used to create high detailed meshes of the heat exchangers. The CFD software Simscale and OpenFOAM have been used to simulate the heat exchangers, using the