Simulation and Experimental Study on the Effects of Cold Air Temperature and Packaging Method on the Pre-cooling Process of Fresh Daylily

In order to explore the effect of different cold air temperatures (1 ℃ and 4 ℃) and packing methods (parallel and perpendicular to the wind direction) on the pre-cooling efficiency of fresh daylily (Hemerocallis citrina Baroni.), computational fluid dynamics (CFD) technology was employed to simulate the pre-cooling efficiency. This study revealed that under the same cold air temperature, fresh daylily packed parallel to the wind direction showed a faster and more uniform pre-cooling rate, leading to better pre-cooling efficiency compared to daylily packed perpendicular to the wind direction. Additionally, lower cold air temperatures were associated with a faster overall pre-cooling rates but poorer uniformity. With the maximum temperature difference of 1.2 ℃ and the simulation accuracy exceeding 92%, the simulation results were consistent with the experimental data. This study proves the feasibility of utilizing CFD numerical simulation to optimize pre-cooling parameters for fresh daylily, and thereby provides a theoretical foundation and technical guidance for the storage and preservation of this produce.