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Ice slurry is a type of cold storage medium with the advantages of high-energy storage density, good fluidity and fast cooling rate, which has the prospect of wide application. Because, the process of making ice slurry often faces problems such as recrystallization, ice blockage and so on. It needs to add some additives, because the additives structural properties can play a good optimization role, can reduce the ice slurry solution supercooling degree, improve the efficiency of ice production, refine the ice crystal particles, improve the ice slurry solution pumping conditions, reduce the size of the pipe diameter. In this paper, the effects of different types of additives in ice slurry solutions are described in detail and the role of additives is analyzed from the microscopic perspective of molecular dynamics. Finally, some suggestions are given for the future application of additives in ice slurry based on the current research situation. [ABSTRACT FROM AUTHOR]

• The exergy analysis model of vacuum ice production device is established. • The results of the exergy analysis of adsorption and condensing vacuum ice production device are compared. • The adsorption vacuum ice production device has the highest exergy efficiency in the adsorption of water vapor. • The design of the flash chamber should consider the enhanced heat and mass transfer in the flashing process. This paper proposes a vacuum ice production device by solid adsorption. An analysis model related to exergy loss and exergy efficiency is established in each component of the vacuum flash ice making system. By comparing the exergy analysis results of adsorption vacuum ice production device and condensing vacuum ice production, this paper has drown an effective method to reduce exergy loss. It has been found that the exergy efficiency of the adsorption vacuum ice production device is 9.64% higher than that of the condensing vacuum ice production device. The exergy efficiency of water vapor adsorption in the adsorption chamber is the highest, while the exergy efficiency of water vapor adsorption in the condensation chamber is the lowest. In order to reduce the energy demand of the device, the heat released by the condenser should be fully utilized to reduce the exergy loss of the condenser. At the same time, the heat and mass transfer of the flash evaporation process should be enhanced when designing the flash chamber, such as optimizing the ice making working fluid to improve the exergy efficiency of the flash chamber. [ABSTRACT FROM AUTHOR]

• Water vapor is trapped using a coupled adsorption chamber with a low temperature condensing coil. • Explore the effect of different additives (MgCl 2 , ethylene glycol, nano Fe 3 O 4) on the vacuum ice making process. • The added of additives is beneficial to the formation of ice slurry and the refinement of ice crystals. • Fe 3 O 4 nanofluid is beneficial to reduce ice making subcooling and improve ice slurry thermal conductivity. • Ethylene glycol is not suitable as an additive for vacuum flash ice making. Being a novel energy storage medium, ice slurry has the advantage of good fluidity, high latent heat and heat transfer efficiency, which has a broad application prospect. In this work, the ice making characteristics of different types of additives (MgCl 2 , ethylene glycol and magnetic iron oxide nanoparticles) in a binary ice system by vacuum flash evaporation under the action of solid adsorption were experimentally investigated. Subcooling, flash rate, ice packing factor, latent heat and thermal conductivity were measured to evaluate the performance of ice production. The results showed that 0.075% wt of iron oxide nanoparticles and 1% wt of MgCl 2 are more suitable to be used as additives for binary ice preparation than ethylene glycol, with the former outperforming the latter. Under optimal conditions, compared with pure water for ice making, the subcooling degree of iron oxide nanofluid was reduced by 55.80%, and the thermal conductivity and ice packing factor were increased by 98.80% and 54.22%, respectively. The subcooling degree of the MgCl 2 solution was reduced by 37.52% and the ice packing factor was improved by 59.51%. Meanwhile, DSC tests showed that the latent heat of the nanofluid was almost independent of the nanoparticle concentration. However, the increase of MgCl 2 solution would cause the decrease of latent heat. In addition, high concentrations of additives can inhibit ice crystal nucleation and growth, but a certain concentration of additives facilitates ice crystal refinement in vacuum ice making process, which is conducive to the transportation of ice slurry. [ABSTRACT FROM AUTHOR]

• Optimization of emulsion ice slurry preparation by response surface methodology. • Experimentally prepared emulsions eliminate water supercooling. • Emulsion ice slurry does not stick to the walls of the flash chamber and has a softer texture than pure water. • Pure water ice slurry is flaky in the vacuum flash state, and emulsion ice slurry is spherical. As a cold storage material, emulsion ice slurry is expected to increase the ice slurry's fluidity because of the emulsion's structural characteristics, which does not adhere to the wall of the cooling vessel. In this paper, surfactants were mixed in the water-oil mixture, and the emulsion with small particle size and high stability was optimized by the response surface method. The emulsion ice slurry was also prepared under vacuum flash evaporation by solid adsorption, and we studied the properties of the emulsion ice slurry under vacuum flash evaporation. The microstructures of pure water ice slurry and emulsion ice slurry under vacuum flash evaporation were observed by metallographic microscopy. [ABSTRACT FROM AUTHOR]