为防止全球气温变暖,替代冷媒R134a和自然冷媒二氧化碳已经用于制冷循环。由于压缩机的压缩量增加,采用这两种冷媒的制冷循环的效率系数变得较低。然而,因为那些冷媒膨胀阀的能量损耗也在增加。带有喷射器的制冷循环能够将膨胀阀的有效能量转化为压缩冷媒的功。本文将叙述喷射器在制冷循环中如何工作,以及效率系数能够增加多少。 To prevent global warming, alternative refrigerant R134a and natural refrigerant carbon dioxide have been used in refrigeration cycles. As the amount of compression of the compressor increases, the efficiency coefficient of the refrigeration cycle using these two refrigerants becomes lower. However, because those refrigerant expansion valve energy loss is also increasing. A refrigeration cycle with an ejector can convert the effective energy of the expansion valve to the work of compressing the refrigerant. This article describes how the ejector operates in a refrigeration cycle and how much the efficiency factor can be increased.