Fundamentals Of Thermodynamics
10th Edition
ISBN: 9781119494966
Author: Borgnakke, C. (claus), Sonntag, Richard Edwin, Author.
Publisher: Wiley,
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Textbook Question
Chapter 5, Problem 5.51P
A heat engine receives 7kW from a 300°C source and rejects heat at 60°C. Examine each of three cases with respect to the inequality of Clausis.
a.
b.
c. Carnot cycle
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A new parabolic dish solar concentrator is being developed to supply electricity to a small remote community. The system operates with a Stirling engine connected to two heat reservoirs HR₁ and HR₂ as shown in Fig. Concentrated solar radiation Q˙ₛᵤₙ=200kW maintains HR₁ at constant temperature Tₕᵣ,₁=700℃, and a high performance heat sink device maintains HR₂ at temperature Tₕᵣ,₂=25℃. After some time of operation, an engineer working on the project realizes that the engine power output is performing below design specifications and only provides a power output of 120kW. After inspecting the system, they discover a contact resistance that causes the thermal communication between the two heat reservoirs and the engine to be imperfect in the sense that a finite temperature difference is required to establish heat transfer between each of the heat reservoirs and the engine.
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Heat engine and refrigerator. Consider a heat engine operating between temperatures Th and
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Chapter 5 Solutions
Fundamentals Of Thermodynamics
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