Numerical and Experimental Investigation on Forced-Air Cooling of Commercial Packaged Strawberries

摘要

The numerical simulation model of forced-air cooling of strawberries in a clamshell and a box was established by using computational fluid dynamics method. The cooling process of the simulation and the experiment results agreed well in different conditions, indicating that the simulation model was validated. The results showed that the 7/8 cooling time was 180 min, 135 min, 108 min and 100 min and the cooling uniformity coefficients were 0.31, 0.22, 0.24, 0.26 when the diameters of B-vent(the vent on the box) were 30 mm, 40 mm, 50 mm, 60 mm, respectively. The 7/8 cooling time decreased and the cooling uniformity coefficient improved, when the shape of C-vent (the vent on the clamshell) changed from round to rectangular. The 7/8 cooling time also deceased and the cooling uniformity coefficient increased, when the area of C-vent with both round and rectangular shapes increased. These results indicate that both B-vent and C-vent had significant effect on reducing the cooling time and the improving cooling uniformity for strawberries, It is suggested that the optimized vent ratio of B-vent (the diameter is 40 mm) and C-vent (15 mm round or 20 mm x 15 mm rectangular) for the current commercial packaged strawberries were 9.4 % and 8.5 %, respectively.