基于CFD的苹果隔板包装预冷温度场研究

Investigation on Pre-cooling Temperature Field in Partition Packaging Based on CFD

温度调控失误和物理损伤是影响采后水果质量损失的关键因素。以单层隔板包装箱和单层普通包装箱为研究对象,采用计算流体力学(Computer fluent dynamic,CFD)非稳态剪切压力SST k-ω三维湍流模型,比较相同初始条件和边界条件下,隔板包装与普通包装内部的温度场分布、风速场分布、冷却时间、冷却速率和冷却均匀性。结果表明:隔板包装和普通包装的冷却时间和冷却速率基本一致,冷却温度差值不超过0. 67℃,冷却速率差值不超过0. 012℃/min,隔板包装温度变异系数略大于普通包装温度变异系数,两种包装具有相同预冷效果,满足冷链运输过程中的预冷需求。对比模拟结果与实验结果,两种结果的均方根误差为1. 13℃,平均相对误差为8. 2%,证明了模拟结果的合理性和准确性。

Temperature mismanagement and physical damage are considered as the most common causes for postharvest losses of fresh fruit. The partition packaging and common packaging without partitions were taken as research objects. A three dimensional mathematical shear stress transport (SST) k ω model of computational fluid dynamics (CFD) was established to simulate the temperature and velocity field distribution of partition packaging and common packaging under the same boundary condition and the same initial condition. Compared with cooling time, cooling rate and cooling uniform of two packages, the partition package and common package were basically the same, the difference of cooling temperature was not more than 0.67℃, the maximum difference of cooling rate was 0.012℃/min, and the coefficient of temperature variation of partition packaging was slightly larger than that of common packaging temperature. The two kinds of packaging had the same pre-cooling effect and met the pre-cooling requirement in cold chain transport. Compared with experimental results, the root mean square error of two packaging results was 1.13℃ and the average relative error was 8.2%, which proved the rationality and accuracy of simulated result. The research result was of great significance for the relationship between balance temperature loss and physical damage.