I Difference between the thermal and mechanical efficiency

AI Thread Summary
The discussion centers on the confusion between thermal and mechanical efficiency in Stirling heat engines. Mechanical efficiency is described as the ratio of work done by the gas to the work output of the engine, while thermal efficiency relates to the thermodynamic performance of the engine. Participants emphasize the importance of clear definitions from sources discussing these terms. There is a consensus that mechanical efficiency should not be used interchangeably with thermal efficiency. Understanding these distinctions is crucial for accurate analysis of heat engine performance.
Poorneshwar 2
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Hello, I'm confused between the difference between the thermal and mechanical efficiency of a Sterling heat engines or heat engines in general. I hope you could be able to guide and help me. Thank you
 
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I don't think there is a difference, but I wouldn't use the term "mechanical efficiency" to refer to a thermodynamic system. Where did you hear it?

[Edit] Google tells me "mechanical efficiency" can be used to describe the mechanical output of a real engine (different from themal/thermo efficiency).
 
I read about the mechanical efficiency of the heat engine in this article. I think that it is the ratio between Qh(work done by the gas) and Wout(work that the heat engine has done). Am i thinking in the right way?

Also, what does thermal efficiency of a heat engine refer to?

Thank you.
 

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Poorneshwar 2 said:
I read about the mechanical efficiency of the heat engine in this article. I think that it is the ratio between Qh(work done by the gas) and Wout(work that the heat engine has done). Am i thinking in the right way?
That sounds right, but your source should include the definition if it is introducing the term.
Also, what does thermal efficiency of a heat engine refer to?
I would think thermal means thermodynamic, but it is possible they are also referring to a real-world, non-ideal process. But again, the text you are reading it from should define it.
 
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