A Transient Model for Simulating the Freezing Process of Molten-salt Coolants

Abstract

Even though molten salts have many useful characteristic, especially as coolants for nuclear reactors, they are prone to freezing due to their high melting point. The solidification of the salt inside the piping system could cause structural damage and stop the flow of coolant with possible serious problems. Modelling the freezing process is therefore of primary importance for nuclear safety. In this study a quasi-steady thermo-hydraulic model has been derived and implemented to describe the transient freezing of molten salts. The partial differential equations describing the solidification/melting of the salt are solved numerically using a combination of standard explicit and implicit methods. Validation of the model is presented based on previous experimental studies for two separate cases.