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CHAPTER
5
The Second Law of Thermodynamics
FIGURE 5-9Part of the heat received by a heat engine is converted to work, while the rest is rejected to a sink.
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5-1
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5-2
FIGURE 5-10Schematic of a steam power plant.
FIGURE 5-14Schematic of a heat engine.
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5-3
FIGURE 5-16A heat-engine cycle cannot becompleted without rejecting someheat to a low-temperature sink.
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5-4
FIGURE 5-23The efficiency of a cooking appliance represents the fraction of the energy supplied to the appliance that is transferred to the food.
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5-5
FIGURE 5-25Basic components of a refrigerationsystem and typical operating conditions.
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5-6
FIGURE 5-26The objective of a refrigerator is to remove QL from the cooled space.
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5-7
FIGURE 5-27The objective of a heat pump is to supply heat QH into the warmer space.
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5-8
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5-9
FIGURE 5-33Proof that the violation of the Kelvin-Planck statement leads to the violation of the Clausius statement.
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5-10
FIGURE 5-34A perpetual-motion machinethat violates the first law ofthermodynamics (PMM1).
FIGURE 5-43Execution of the Carnot cycle in a closed system.
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5-11
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5-12
FIGURE 5-44P-V diagram of the Carnot cycle.
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FIGURE 5-45P-V diagram of the reversed Carnot cycle.
5-13
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5-14
FIGURE 5-46The Carnot principles.
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5-15
FIGURE 5-47Proof of the first Carnot principle.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.FIGURE 5-49The arrangement of heat engines used to develop the thermodynamic temperature scale.
5-16
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FIGURE 5-55The fraction of heat that can be converted to work as a function of source temperature (for TL = 303 K).
5-17
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5-18
FIGURE 5-57No refrigerator can have a higher COP than a reversible refrigerator operating between the same temperature limits.
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5-19
FIGURE 5-63The condenser coils of a refrigerator must be cleaned periodically, and the airflow passages must not be blocked to maintain high performance.
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