摘要: |
本文通过理论计算和实验研究,分析了校准箱温度、迎面风速及循环倍率对CO2冷风机性能的影响规律。建立数学模型进行理论计算,结果表明:当校准箱温度从﹣30 ℃升至﹣10 ℃时,传热系数增大5.8%,相应的制冷量增大5.9%;在计算所用工况下,最佳迎面风速(3.2 m/s)使冷风机性能最佳;冷风机传热系数随着循环倍率的增长先呈急剧增长趋势之后趋于平缓,循环倍率约为3时最佳。对比CO2冷风机各项实验值和理论计算值,结果显示理论计算值高于实验值,误差为14.8%~25%,但理论计算值和实验值的变化趋势基本相同,验证了数学模型的合理性。 |
关键词: CO2冷风机 制冷量 传热系数 循环倍率 |
DOI: |
Received:June 29, 2017 |
基金项目: |
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Theoretical Calculation and Experimental Study on the Performance of CO2 Air-cooler |
Li Kun, Shen Jiang, Wang Xiaole
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(Refrigeration Key Laboratory of Tianjin, Tianjin University of Commerce) |
Abstract: |
The effect of the temperature of the calibration tank, face velocity, and circulation rate on the performance of a CO2 air-cooler are analyzed using theoretical calculation and experimental study. The theoretical calculation is carried out by establishing a mathematical model, the results of which show that when the temperature of the calibration tank increases from ?30℃ to ?10℃, the coefficient of the heat transfer increases by 5.8%, and the corresponding refrigerating capacity increases by 5.9%. Under the calculation conditions, the best face velocity (3.2 m/s) occurs, providing the best air-cooler performance; in addition, the coefficient of heat transfer of the air-cooler increases rapidly with an increase in the circulation rate, and the growth tends to be smooth, with the best circulation rate at about three. Comparing the experimental value with the theoretical calculation of the CO2 air-cooler, the results show that the theoretical calculation is higher, the error of which is between 14.8% and 25%; however, the trends between the theoretical calculation and the experimental value are basically the same, verifying the rationality of the mathematical model. |
Key words: CO2 air-cooler refrigeration capacity coefficient of heat transfer circulation rate |