Numerical modeling of forced-air cooling of palletized apple: Integral evaluation of cooling efficiency

This study proposed an integrated approach to evaluate the efficiency of forced-air cooling of apples stacked on pallets. Computational fluid dynamics (CFD) modeling was used to evaluate the cooling rate, uniformity, moisture loss, and energy consumption during precooling of apples. Experiments were conducted to quantify the incidence of chilling injury. A reasonable increase in cooling rate and uniformity was obtained with an increase in air-inflow rate to 2.31 L s−1 kg−1; any further increase in air-inflow rate will lead to a relatively low increase in cooling rate and uniformity, but a significant increase in energy consumption and cooling injury. An exponential relationship exists between fan power (Pw) and pressure differential (ΔP) as well as between total fan energy consumption (Ec) and air-inflow rate (Ec = hxk). Finally, the mass loss of fruit is primarily influenced by cooling time rather than air-inflow rate.