ABSTRACT Efficient postharvest cooling is essential to preserve the quality of perishable agricultural produce such as potatoes. This study presents a coupled computational fluid dynamics and discrete element method (CFD–DEM) model to evaluate the pressure‐difference precooling performance of postharvest potatoes stacked in plastic crates under varying airflow velocities (1.0, 1.5, 2.0, and 2.5 m/s). The model captures the heterogeneous packing structure and realistic airflow–heat transfer behavior within the crate. Four key performance indicators were assessed: precooling time, cooling rate, cooling uniformity, and energy consumption. Experimental validation showed good agreement with simulation results, with an RMSE of 1.375°C. Results demonstrated that increasing air velocity from 1.0 m/s to 1.5 m/s substantially enhanced cooling efficiency and temperature uniformity, with only minor improvements observed beyond 1.5 m/s. Conversely, fan energy consumption increased sharply at higher velocities. A power‐law relationship ( E w = aV b ) was established between energy use and velocity. This study identified 1.5 m/s as the optimal inlet air velocity for the experimental setup used in this research, balancing cooling performance and energy efficiency. For different packing densities or other agricultural products, the optimal velocity may vary. This work provides theoretical and practical insights into airflow optimization for root crop precooling systems.
Wang et al. (Wed,) studied this question.