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JMack23
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So I can follow the sequence of operations: the refrigerant enters the compression stage as a saturated vapour(a gas?) and it's compressed raising the temperature of the refrigerant, it gives off some of this heat to the surrounding ambient air, causing a decrease in temperature and an according phase change to liquid(does it all change to liquid at this point or is there a mix of liquid and vapour?). It's then put through an expansion device which causes the pressure to drop and expanding the liquid. This is what I don't get, if it's in a liquid state prior to this stage then why use the expansion device? Is it for further cooling? and then the final stage the liquid absorbs heat from the warmer air of the interior of the fridge causing it to become a gas again and so the cycle repeats. Also, intuitively it makes sense to me that there has to be some work input to the system to be able to extract the heat but it seems kinda strange to me since the main aim of the cycle is to make the refrigerant as cool as possible to be able to extract heat from the inside of the fridge so why would we want to make the initial starting condition HOTTER? Surely then this makes it more difficult(and requires more energy) to go from this elevated hotter temperature(compression stage) to the final cool stage where evaporation takes place. I'm a bit confused. If anyone could offer some clarification I would be tremendously grateful, thanks.