Digital simulation of condensation and water loss in ventilated lychee packaging

Lychee quality deteriorates rapidly post-harvest. Appropriately ventilated packaging can help maintain quality during the supply chain. However, interruptions in the cold chain can lead to temperature differences between the inside and outside of packages, increasing condensation and liquid water formation, which negatively affects lychee quality. This study used numerical simulations to analyse forced ventilation in different packaging structures, focusing on how the number of top openings affects internal temperature, humidity, condensation, and water loss. Additionally, the stacking of packaged lychee was modelled to predict water loss and condensation under actual supply conditions. The results showed that increasing the number of package openings reduces humidity differences and condensation, with eight openings resulting in 9.18 % less water loss rate compared to six openings. Six openings reduced condensation by 23.67 % compared to four openings. Furthermore, during storage and transportation, the amount of water loss and condensation varied by location, with lychees near the air outlet losing less water but experiencing more condensation. The findings of this study provide insights into reducing in-package condensation and water loss in the lychee supply chain, offering a reference for optimising storage and transportation strategies.