Development and validation of a one-dimensional solidification model-Part I: Analytical model

The utilization of high-freezing point coolants in Gen IV reactors offers advantages in terms of high thermodynamic efficiency and inherent safety. However, it also introduces the risk of coolant solidification, which has been identified as a design basis accident for these reactor types. Accurate one-dimensional (1D) solidification models play a crucial role in reactor licensing and operation. Nevertheless, existing 1D models primarily focus on the growth of the solidified layer thickness, neglecting the important mushy zone effects that occur at the boundary layer overlap. This paper presents a novel general solidification model that incorporates the mushy zone effects and is applicable to high-freezing point coolants. The model has demonstrated favorable accuracy, with a maximum relative error of 10% when compared to experimental data. The findings highlight that the omission of mushy zone effects can lead to significant deviations from the actual scenario.