CO2冷风机性能数值模拟与实验研究

Numerical simulation and experimental research on performance of CO_2 air cooler

建立了CO2冷风机的数学模型,并对蒸发温度、循环倍率、迎面风速以及换热温差等影响CO2冷风机的性能参数进行了数值分析和实验研究。结果表明:蒸发温度从-47℃升高到-22℃,蒸发温度每升高1℃会使冷风机传热系数有0. 86%的提升;冷风机的传热系数随循环倍率的增大呈先上升后下降的趋势,模拟值和实验值均在循环倍率为3时达到最大;迎面风速在2. 5m/s^2. 9m/s之间传热系数增幅最大,在风速达到3. 2m/s后增速减缓;随着传热温差的减小冷风机的传热系数也逐渐较小;数值模拟值与实验值所得到的趋势相同,偏差范围7. 8%~20.9%,验证了数学模型的合理性。

In this paper, a mathematical model of CO2 air cooler was established and the performance parameters of CO2 air cooler such as evaporation temperature, circulation ratio, face velocity and heat exchange temperature difference were analyzed numerically and experimentally. The results show that the evaporation temperature increases from -47℃ to -22℃, the in- crease of the evaporation temperature by 1℃ will increase the heat transfer coefficient of the air cooler by 0. 86%. The heat transfer coefficient of the air cooler increases first and then decreases with the increase of the circulation ratio, both the simulated value and the experimental value reach the maximum at a circulation ratio of 3. The face velocity increases from 2.5m/s to 2.9m/s and the heat transfer coefficient increases the most, after the wind speed reaches 3.2m/s, the growth rate slows down. As the heat transfer temperature difference decreases, the heat transfer coefficient of the air cooler gradually decreases. The numeri- cal simulation values and the experimental values have the same trend, and the deviation range is 7.8% ~ 20.9%, whieh verifies the rationality of the mathematical model.