Undergrad Difference between the thermal and mechanical efficiency

[Poorneshwar 2]

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

 

[russ_watters]

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).

 

[Poorneshwar 2]

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.

 

[russ_watters]

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.