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【中文摘要】 研究利用变制冷剂流量制冷循环的实验平台结合流动显示方法发现:1)蒸发器出口的制冷剂气液两相流流型存在过热蒸汽流和雾状流两种型式,二者之间存在一个转变过渡区域,此时,两种流型闪动交替出现,回气温度随机性波动;2)膨胀阀出口(即蒸发器入口)的制冷剂气液两相流的流型存在液-气分相流、泡-气分相流两种型式,二者之间也存在一个转变过渡区,此时两种流型交替出现,制冷循环周期性振荡,蒸发温度、回气温度、排气温度等参数周期性波动;且振荡周期随着制冷循环制冷剂流量的增大而缩短。 【英文摘要】 The experiment was conducted with a variable refrigerant volume refrigeration loop and the flow visualization to investigate the instability of refrigeration cycle. The results show that superheat vapor flow and mist flow exist at the outlet of the evaporator, and a transform zone occur between them. Moreover, there are liquid/vapor flow and liquid/bulbs flow at the inlet of the evaporator, and a transform zone also occur between them, leading to periodic oscillation of the refrigeration cycle. In addition, the increase of refrigerant flow rate will reduce the periodic oscillation. 【中文关键词】 热工学; 制冷循环; 不稳定性; 气液两相流; 流动可视化/流动显示; 变制冷剂流量/变容量/变频空调 【英文关键词】 Pyrology; Refrigeration cycle; Instability; Vapor-liquid two-phase flow pattern; Flow visualization/flow display; Variable refrigerant volume/variable capacity /inverter chiller