Numerical simulation of dynamic layer freeze desalination within an indirect contact freeze crystallizer

Abstract

In the current study, a dynamic layer freeze desalination system is simulated numerically. The computational domain is a two-dimensional rectangular channel which contains inlet and outlet flows, and the simulation is performed using computational fluid dynamics. A pre-concentrated mixture is considered as the feed solution with an initial temperature and concentration of 257 K and 0.2 kg/kg, respectively. In this work, since the simulation parameters such as temperature and species mass fraction have high importance across the entire domain, the k–ω shear stress transport turbulence model was selected. A parametric study on the effect of the heat flux of the cold wall on the ice salinity and desalination rate is performed using three cases with heat fluxes of −1000, −1500, and −3000 Wm−2. It is observed that the ice generation speed in the case with a heat flux of −3000 Wm−2 is 3.28 times greater compared to the case with −1000 Wm−2 and its desalination rate is only 2.59% lower. The effect of the inlet velocity on the mentioned parameters is also investigated. It is observed that the cases with turbulent flow have approximately 19% and 23% lower ice salinity compared to the case with laminar flow.