- #1
xspook
- 19
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Homework Statement
Derive a formula for the efficiency of the Diesel cycle, in terms of the compression ratio V1/V2
Homework Equations
e=[itex]\frac{W}{Q_{h}}[/itex]
w= ∫pdV
The Attempt at a Solution
Now I know I should have used e=1-[itex]\frac{Q_{c}}{Q_{h}}[/itex] to get it but he said it is possible using e=[itex]\frac{W}{Q_{h}}[/itex]
I know that W_{4-1} is equal to zero and W_{2-3} is equal to P_{2}(V_{3}-V_{2})
what I don't know is how he got
W_{1-2} = [itex]\frac{e}{1-δ}[/itex]*cv[itex]^{-δ+1}[/itex] = [itex]\frac{1}{1-δ}[/itex]*(P_{2}V_{2}-P_{1}V_{1})
and
W_{3-1} = [itex]\frac{e}{1-δ}[/itex]*cv[itex]^{-δ+1}[/itex] = [itex]\frac{1}{1-δ}[/itex]*(P_{4}V_{4}-P_{3}V_{3})