The electromechanical COP of the flash cooler is like the efficiency of the system, which in refrigerators it can be greater than one, and thus it is termed a COP. The electromechanical COP=2.6 for a new flash cooler being designed for a pasteurization milk vat. The refrigerant is R−134a, for the refrigerator to meet the process requirements it must be able to cool 100 liters of hot milk at 70 ∘
C to 4 ∘
C in 5 min, to enhance the heat transfer for the cooling process the milk in the vat is agitated with a paddle imputing 1 kW of mechanical work. The heat capacity of the milk is 4.035 kJ/kg/K