低气压环境对空调器制冷能力的影响初探

分别从理论和实验两方面研究低气压环境对蒸发器空气侧换热系数的影响。低气压环境下较小的空气密度会降低蒸发器空气侧换热系数，较小的空气绝对含湿量造成潜热换热量的减小。低气压环境同时会影响制冷剂侧的沸腾换热，并造成制冷量的进一步下降。

Effect of Low Air Pressure on the Cooling Capacity of Direct Evaporative Air-conditioning

Convective heat transfer coefficient on the air side of direct expansion evaporator under low air pressure is studied by theory and experiment respectively. Results show the convective heat transfer coefficient will diminish along with the density of air under low pressure. The lower absolute humidity of air under lower pressure will reduce the difference of water vapor pressure between the air supply and air return, and the quantity of latent heat transfer between the evaporator and the air will decrease accordingly. Meanwhile, the process of heat transfer on the refrigerant side will change under low air pressure, which will make the refrigerating capacity become even smaller.