Santhosh Senguttuvan , Hyeong-Geun Kim , Min-Seob Shin , Youngho Rhee , Jaehyun Park , Sung-Min Kim
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引用次数: 0
Abstract
Improving the performance of a refrigerated container is crucial in effectively preserving thermal-sensitive cargo. The combined effect of vertical airflow resistance and airflow short-circuiting in air gaps play a vital role in cargo cooling. This study numerically investigates the effects of cargo vertical airflow resistance and air gaps between cargo pallets using two commonly used apple packaging boxes, each stacked in six different cargo pallet arrangements. A heat transfer enhanced refrigerated container design and a numerical model developed from the present authors’ previous studies are used. The numerical model uses the porous medium model to incorporate the refrigeration unit and cargo within the refrigerated container. Additionally, the numerical domain includes the T-bar floor in the refrigerated container. Initially, the airflow characteristics based on vertical airflow resistance and air gaps are discussed. Then, the corresponding effects on cargo cooling are addressed. Results show that the air gaps between the cargo pallets have positive and negative effects on cargo cooling. In cargos with lower vertical airflow resistance, an increase in air gaps leads to reduced cargo cooling and elevated temperature non-uniformity. Conversely, cargos with higher vertical airflow resistance experience increased cooling rates and reduced temperature non-uniformity with the increase in air gaps. However, avoiding airflow short-circuiting through the air gaps between the cargo pallets and improving the vertical airflow inside the cargo pallets can provide better cargo cooling, which outweighs the positive cooling effect of the air gap.
提高冷藏集装箱的性能对于有效保存热敏性货物至关重要。垂直气流阻力和气隙中的气流短路共同作用,对货物冷却起着至关重要的作用。本研究使用两种常用的苹果包装箱,分别以六种不同的货盘排列方式堆叠,对货物垂直气流阻力和货盘间气隙的影响进行了数值研究。本研究采用了一种热传导增强型冷藏集装箱设计,并使用了作者先前研究中开发的数值模型。数值模型采用多孔介质模型,将制冷装置和货物纳入冷藏集装箱内。此外,数值域还包括冷藏集装箱内的 T 形杆地板。首先,讨论了基于垂直气流阻力和气隙的气流特性。然后,讨论对货物冷却的相应影响。结果表明,货盘之间的空气间隙对货物冷却有正面和负面影响。在垂直气流阻力较小的货物中,气隙的增加会导致货物冷却效果降低,温度不均匀度升高。相反,垂直气流阻力较大的货物,随着气隙的增大,冷却率会提高,温度不均匀度也会降低。然而,避免气流通过货盘之间的气隙短路,改善货盘内部的垂直气流,可以更好地冷却货物,其冷却效果超过了气隙的正面冷却效果。
期刊介绍:
The International Journal of Refrigeration is published for the International Institute of Refrigeration (IIR) by Elsevier. It is essential reading for all those wishing to keep abreast of research and industrial news in refrigeration, air conditioning and associated fields. This is particularly important in these times of rapid introduction of alternative refrigerants and the emergence of new technology. The journal has published special issues on alternative refrigerants and novel topics in the field of boiling, condensation, heat pumps, food refrigeration, carbon dioxide, ammonia, hydrocarbons, magnetic refrigeration at room temperature, sorptive cooling, phase change materials and slurries, ejector technology, compressors, and solar cooling.
As well as original research papers the International Journal of Refrigeration also includes review articles, papers presented at IIR conferences, short reports and letters describing preliminary results and experimental details, and letters to the Editor on recent areas of discussion and controversy. Other features include forthcoming events, conference reports and book reviews.
Papers are published in either English or French with the IIR news section in both languages.