Solution Found!
Using the KelvinPlanck statement of the second law of
Chapter 5, Problem 5.8(choose chapter or problem)
Using the Kelvin–Planck statement of the second law of thermodynamics, demonstrate the following corollaries:
(a) The coefficient of performance of an irreversible refrigeration cycle is always less than the coefficient of performance of a reversible refrigeration cycle when both exchange energy by heat transfer with the same two reservoirs.
(b) All reversible refrigeration cycles operating between the same two reservoirs have the same coefficient of performance.
(c) The coefficient of performance of an irreversible heat pump cycle is always less than the coefficient of performance of a reversible heat pump cycle when both exchange energy by heat transfer with the same two reservoirs.
(d) All reversible heat pump cycles operating between the same two reservoirs have the same coefficient of performance.
Questions & Answers
QUESTION:
Using the Kelvin–Planck statement of the second law of thermodynamics, demonstrate the following corollaries:
(a) The coefficient of performance of an irreversible refrigeration cycle is always less than the coefficient of performance of a reversible refrigeration cycle when both exchange energy by heat transfer with the same two reservoirs.
(b) All reversible refrigeration cycles operating between the same two reservoirs have the same coefficient of performance.
(c) The coefficient of performance of an irreversible heat pump cycle is always less than the coefficient of performance of a reversible heat pump cycle when both exchange energy by heat transfer with the same two reservoirs.
(d) All reversible heat pump cycles operating between the same two reservoirs have the same coefficient of performance.
ANSWER:Step 1 of 4
a.) The COP of a reversible refrigerator will always be greater than irreversible refrigerator . because in the case of an irreversible process there will always be heat loss more than that of a reversible engine. Also all refrigerators work on cyclic processes and hence net entropy generation is zero. Hence it has higher COP than an irreversible refrigerator . which only depends on temperature levels.