A dynamic model of Ostwald ripening in ice suspensions

A computer-based dynamic model of Ostwald ripening in ice suspensions in a storage tank containing crystal growth kinetics, population, mass and energy balances has been developed to simulate the development of ice crystal size distributions during adiabatic ice slurry storage. The model assumed a homogeneously mixed storage tank with neither inlet nor outlet of mass. Growth and melting of ice crystals were caused by differences in equilibrium temperatures between differently sized crystals and crystal growth kinetics were based on heat and mass transfer. Validation with experimental results for different types and concentration of solutes, different ice fractions and different mixing rates showed that the model is able to predict the development of the average crystal size in time. Especially, the former two parameters have a strong effect on the ripening process, while the effect of the latter two is small. A difference between experimental and simulation results was found for the shape of the crystal size distribution curve after storage, which had a slightly longer tail during the experiments.