Thermal analysis of ice slurry generation from fixed volumes of brine: experimental data and theoretical modelling of the phenomena

This paper reports on a comprehensive experiment undertaken to make a 500kg batch of ice slurry from an initially ambient temperature (18C) brine solution (5% NaCl concentration). An industrial chiller operating with constant electrical power supply in a constant temperature environment was used to produce the ice slurry over a 6 hour period. During this time the temperature of the brine and the salt concentration in the brine were constantly monitored. The data highlighted the non-linear rate of temperature drop in the brine/ice mix. A mathematical model was developed to represent the physical phenomena occurring during the manufacture of the ice. The model predictions were compared with experimental findings. The model gave excellent qualitative and good quantitative agreement with the experimental data. Further improvements in the model predictions will only be achieved by increasing the model complexity, which will probably mean resolving the fine details of fluid flow within the ice slurry, perhaps by using Computational Fluid Dynamics, Large Eddy Simulation or even Full Simulation. It is however believed that the quality of the quantitative agreement obtained with the current model is adequate in most industrial applications.