In this study

a three-dimensional mathematical model was established to simulate the pre-cooling process for blueberries in boxes containing three holes. The pre-cooling time and non-uniformity of blueberries with variable wind speeds were analyzed in three types of pre-cooling boxes. Considering the capacity of blueberries in different boxes

a density pre-cooling factor was proposed to evaluate comprehensively the quality of blueberries and the pre-cooling time of the pre-cooling process. The numerical results showed that the pre-cooling time of blueberries decreased with increasing wind speed. At the same pre-cooling wind speed

more than 1/3 of the blueberries could be carried in the No. 3 box

and the 7/8 pre-cooling time increased by less than 5 min. In addition

the unevenness increased by 0.2–0.4

and the density pre-cooling coefficient increased by as much as 3.09 kg/(m3.min). Based on the factors considered

the optimal pre-cooling speed of blueberries was 1.5 m/s. Although the unevenness of cooling increased in the No. 3 box

the utilization rate of pre-cooling storage could be enlarged effectively.