| 摘要: |
| 合理的厢内温度场是保证冷藏车运输货物品质、节能降耗的关键因素之一。为提高厢内温度场的均匀性，本文提出了单温区冷藏车的梯级送风模式。无梯级送风时，冷风在车厢内形成整体环流，流动方向较为集中，不利于整体降温；有梯级送风时，车厢顶部增加了风机，冷风速度得以提高，且流动方向更加分散，有利于提高整体降温速度和温度场均匀性。建立了冷藏车厢的仿真模型，利用CFD研究梯级送风对空仓时冷藏车厢内温度场的影响，并进行了实验验证。以射流区平均温度、车厢内整体平均温度、温度场不均匀系数和温度极差作为评价指标，对实验中采集到的温度数据进行对比分析。结果表明：梯级送风模式能够有效降低冷藏车厢内的射流区平均温度、整体平均温度、温度场不均匀系数，减小温度极差，提高降温速度；在射流区，梯级送风的影响最为显著，该处的降温幅度和降温速度都有明显优化；在车厢尾部近地面的拐角处，梯级送风的降温效果虽不明显，但降温速度明显加快。 |
| 关键词: 冷藏车 计算流体力学 数值模拟 梯级送风 温度场 |
| DOI： |
| 投稿时间：2019-08-23 修订日期：2019-10-31
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| 基金项目:国家自然科学基金项目（51175304）；山东省自然科学基金（ZR2017MEE052）；日照市科技创新专项（2019CXZX1110）资助。 |
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| Effect of Cascade Air Supplyon Temperature Distribution in Refrigerated Truck |
| Zhao Shi,Jiang Zhaoliang,Ding Zhaolei,Wang Jiamin,Hou Guodong,Ge Pinghai |
| (Key Laboratory of High Efficiency and Clean Machine Manufacturing, Ministry of Education, Shandong University;Rizhao Intelligent Manufacturing Institute, Shandong University;School of Intelligent Manufacturing and Service, Shandong Institute of Commerce and Technology;Shandong Wuzheng Group Co. Ltd.) |
| Abstract: |
| Reasonable temperature distribution within a carriage guarantees the quality of transported cargo and improves energy efficiency. Thus, it is important to develop a refrigerated truck with a uniform temperature distribution to improve its transport capacity. Therefore, a cascade air supply mode was presented to improve the uniformity of the temperature field of the single-temperature refrigerated truck. When there is no cascade air supply system, the cold air forms a circulation in the refrigerated truck. The flow of the cold air is in a specific direction, which is not conducive to the overall cooling of the carriage. In a cascade air supply system, fans are added at the top of the carriage. The velocity of the cold air is increased, and the flow direction is more diverse, which is beneficial for improving the speed of overall cooling and uniformity of the temperature field. A simulation model of a single-temperature refrigerated truck was established to optimize the temperature distribution within the refrigerated carriage. The influence of cascade air supply system on the temperature field of the refrigerated truck was investigated via computational fluid dynamics (CFD). Subsequently, a contrast experiment was conducted to verify the results of the simulation. The average temperature of the jet region, global average temperature, non-uniformity coefficient of temperature field, and the difference between the highest temperature and lowest temperature were used as the evaluation criteria. The results indicated that the cascade air supply system can effectively reduce the average temperature of the jet region, global average temperature, non-uniformity coefficient of temperature field in the refrigerated truck, the difference between the highest temperature and lowest temperature. Furthermore, it can increase the cooling velocity. The decrease in average temperature and increase in cooling velocity were evidently optimized because of the cascade air supply system, especially within the area of the jet region. The decrease in temperature in the corner of the rear carriage was not obvious. However, the cooling velocity was evidently increased. |
| Key words: refrigerated truck computational fluid dynamics (CFD) numerical simulation cascade air supply temperature field |
