THERMODYNAMIC SIMULATION AND PERFORMANCE ANALYSIS OF RAW MILK RAPID COOLING SYSTEMS

Refrigerants plays an important role in the efficiency of rapid cooling systems of raw milk. Therefore,it is necessary to study the impact of different refrigerants on the performance of milk-cooling systems. By using Helmholtz free energy equations of state,this work simulates the coefficient of performance (COP) of raw milk rapid cooling systems using six refrigerants. The six refrigerants are compared according to COP and safety and environmental requirements. The results show that among these refrigerants R22 could be the best choice in terms of the overall performance. Since the rapid cooling systems using pure refrigerants have the problem with large heat transfer temperature difference,we infer that zeotropic refrigerants having temperature glides can alleviate the problem in some extent and improve the energy efficiency of raw milk rapid cooling systems.