| Abstract:As a good storage and transportation coolant, ice slurry has a broad application prospects in the air conditioning and refrigeration industry. The dynamics evolution of ice crystals has important impact on the flow and heat transfer characteristics of ice slurry cooling system in ice slurry storage process. In this paper, population balance model is used to study the dynamics evolution process of ice crystals. Population balance model is used to take a numerical simulation of the dynamics evolution process of ice crystals to get the principle of ice crystal size distribution with time. Then it can provide guidance for ice slurry storage experiments as well as the optimization of ice storage device.At first, the paper gets an overview of the mechanism of ice slurry generation, and analyze the kinetic events related to the ice evolution process of ice slurry storage. It proves that the mechanism of ice slurry generation is mainly associated with the crystallization process of water molecules in the solution, and the crystallization process mainly includes three stages which are supersaturation, nucleation and growth.Kinetic events of ice crystals in ice slurry storage include nucleation, growth, aggregation and breakage. Different kinetic events has different mechanism.Secondly, the application of population balance model as well as the concept are introduced. Population balance equation are simplified the equation according to its characters, then the simplified equation is disserted. The physical parameters, initial conditions and boundary conditions obtained from the ice slurry storage experiment are used to solve population balance equation by taking into the discrete equations.It shows through the comparison of the numerical solutions and experimental values that the tendency of the ice particle size distribution curve from experiment is consistent with the curve from simulation, and maximum error of the two curves do not exceed10%. Therefore, using population balance model to simulate the dynamical evolution of ice crystals in ice slurry storage is effective. Finally, population balance model is used to simulate the changes of ice crystal particle size over time under the conditions of different types of additives, different concentration of additives, ice rate and attrition rate in ice slurry storage. According to the simulation results, the effects of type and concentration of additive, ice rate and attrition rate on the evolution of ice particle size were analyzed. The methods to inhibit the excessive growth of ice crystals and the principle of selecting the ice slurry state parameters is got through the research on the influencing factors of ice particle size distribution evolution in ice slurry storage. |
PDF Full Text Request