Numerical simulation of fish freezing process by immersion cooling and cold air blasting methods

A three dimensional simulation of cooling and freezing process of fish as a complex geometry is presented. The 3d geometry of the fish was produced by digitizing and the thermo-physical properties of the fish were considered as functions of temperature and water content of the fish. Heating loads and product temperatures during chilling, freezing and post cooling processes for immersion cooling method in brine and for cold air blasting method were predicted. The influence of effective parameters such as initial temperature and fish water content are also investigated on processing time. Because of the slow freezing rate in immersion cooling technique, the results show that the initial temperature of fish highly affects freezing time. We suggest that a combination of immersion and cold air blasting methods will decrease the freezing time in comparison with immersion method when solely applied. Comparison of temperature distribution in present study shows a good agreement with other numerical and experimental results