Solar storage systems using salt hydrate latent heat and direct contact heat exchange—I preliminary design considerations

The operating characteristics of a salt hydrate latent heat storage system, using Glauber's salt and direct contact heat exchange through an immiscible heat transfer fluid, have been studied theoretically. Drop dynamics and heat transfer models from the literature were used to predict the system behaviour for a range of conditions involving heat transfer fluid inlet temperature and drop size, composition and crystallization temperature of the salt and vessel contact height. The results of these calculations are used to guide the specification of an approx. scale pilot heat storage unit which has been constructed and operated successfully.