cengel ch10
TRANSCRIPT
CHAPTER
10
Refrigeration Cycles
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10-1
FIGURE 10-1The objective of a refrigerator is to remove heat (QL) from the cold medium; the objective of a heat pump is to supply heat (QH) to a warm medium.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.FIGURE 10-2Schematic of a Carnot refrigerator and T-s diagram of the reversed Carnot cycle.
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FIGURE 10-3Schematic and T-s diagram for the ideal vapor-compression refrigeration cycle.
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FIGURE 10-4An ordinary household refrigerator.
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FIGURE 10-5The P-h diagram of an ideal vapor-compression refrigeration cycle.
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FIGURE 10-7Schematic and T-s diagram for the actual vapor-compression refrigeration cycle.
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FIGURE 10-9A heat pump can be used to heat a house in winter and to cool it in summer.
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FIGURE 10-10A two-stage cascade refrigeration system with the same refrigerant in both stages.
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FIGURE 10-12A two-stage compression refrigeration system with a flash chamber.
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FIGURE 10-14Schematic and T-s diagram for a refrigerator–freezer unit with one compressor.
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FIGURE 10-15Linde-Hampson system for liquefying gases.
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FIGURE 10-16Simple gas refrigeration cycle.
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FIGURE 10-17A reversed Carnot cycle produces more refrigeration (area under B1) with less work input (area 1A3B).
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FIGURE 10-18An open-cycle aircraft cooling system.
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FIGURE 10-19Gas refrigeration cycle with regeneration.
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FIGURE 10-21Ammonia absorption refrigeration cycle.
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FIGURE 10-22Determining the maximum COP of an absorption refrigeration system.
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FIGURE 10-23When one of the junctions of two dissimilar metals is heated, a current I flows through the closed circuit.
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FIGURE 10-24When a thermoelectric circuit is broken, a potential difference is generated.
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10-20
FIGURE 10-25Schematic of a simple thermoelectric power generator.
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FIGURE 10-26A thermoelectric power generator.
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FIGURE 10-27When a current is passed through the junction of two dissimilar materials, the junction is cooled.
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FIGURE 10-28A thermoelectric refrigerator.