(a)
The efficiency of a diesel engine
(a)
Answer to Problem 24PQ
The efficiency of a diesel engine is given by
Explanation of Solution
Write the expression to calculate efficiency of the diesel engine.
Here,
Write the expression for the energy when heat enters the engine from the hot reservoir through isobaric process
Here,
Write the expression for the energy when heat leaves the engine to the cold reservoir through isochoric process
Here,
For an adiabatic process at
Here,
For an adiabatic process at
Here,
Write the expression for specific heat capacity.
Substitute (II), (III) in (I).
Substitute (IV), (V), (VI) in (VII).
At
Conclusion:
Substitute (IX) in (VIII).
Hence, the efficiency of a diesel engine is given by
(b)
The efficiency of the diesel engine represented by Figure P22.24.
(b)
Answer to Problem 24PQ
The efficiency of the diesel engine is
Explanation of Solution
Rewrite (X).
Use
Conclusion:
Substitute
Therefore, the efficiency of the diesel engine is
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Chapter 22 Solutions
Physics for Scientists and Engineers: Foundations and Connections, Advance Edition, Volume 2
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