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Calculating work output of an engine, using ideal gas

  • #1

Homework Statement



A model Stirling engine uses n = 8.04 × 10–3 mol of gas (assumed to be ideal) as a working substance. It operates between a high temperature reservoir at TH = 98.0 °C and a low temperature reservoir at Tc = 25.0 °C. The volume of its working substance doubles during each expansion stroke. It runs at a rate of 0.7 cycles per second. Assume the engine is ideal.

How much work does the engine do per cycle?


Homework Equations



W(eng) = Qh - Qc

The Attempt at a Solution



I assume that you have to find the energy input and output by using the temperatures, and the mol of gas, taking into account it's an ideal gas. However, taking the first step is the problem. I have no clue how to work out Qh and Qc, from the given data. Or perhaps there's some other way you have to solve it?
 
Last edited:

Answers and Replies

  • #2
diazona
Homework Helper
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What does the problem actually ask you to calculate? You don't seem to have included that in the problem statement... does it actually say you need to find the energy input and output, or are you just guessing at that?
 
  • #3
I can't believe I forgot to put that question in. I edited the original - sorry about that.
 
  • #4
Redbelly98
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
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Have you drawn the PV diagram for an idealized Stirling cycle? If not, that would help with figuring out what's going on.
 

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