第一节工质的性质一、状态参数制冷机是利用一些物质的状态变化,将热量从低温空间取出,并放给周围介质的一种机器。而热力学是研究热能与机械能相互转变的一门学科,因此在作制冷机系统讲座开始必须对热力学作一简单的介绍。在制冷机中进行状态变化的物质称之为工质或制冷剂。现在在制冷机中常用的制冷剂有氨和氟利昂。制冷剂在制冷系统中有时为液体,有时为气体,有时压 The first section of the nature of the working fluid First, the state parameters Refrigerator is the use of some material changes in state, the heat removed from the low-temperature space, and put the surrounding medium of a machine. Thermodynamics is a discipline that studies the mutual transformation of thermal energy and mechanical energy. Therefore, we must make a brief introduction to thermodynamics at the beginning of the lecture on refrigeration system. Substances that change state in a refrigerator are called working fluids or refrigerants. Refrigerants commonly used in refrigerators now include ammonia and freons. Refrigerants are sometimes liquid, sometimes gas, and sometimes pressure, in refrigeration systems