- #1

- 264

- 37

- Homework Statement
- A reversible heat engine extracts

heat QH > 0 from a reservoir at temperature TH and heat QM = aQH > 0

from a reservoir at temperature TM ≤ TH while rejecting waste heat QC > 0

to a reservoir at temperature TC ≤ TM.

Derive an expression for the effi ciency of this three- reservoir heat

engine in terms of a and the three temperatures TH, TM, and TC ,

where the effi ciency is the total work produced divided by the total

heat extracted from the two hotter reservoirs.

- Relevant Equations
- (1 − TH /TC )/(1 + a) + (1 − TM /TC )a/(1 + a)

My book states the answer to this problem is
.

I have gotten very close to the answer. My problem is my Tc/th and tc/tm are flipped compared to the solution.

I feel like I am missing something in my algebra but can't see where I am going wrong. Could I get some help identifying where my mistake is.

I have gotten very close to the answer. My problem is my Tc/th and tc/tm are flipped compared to the solution.

I feel like I am missing something in my algebra but can't see where I am going wrong. Could I get some help identifying where my mistake is.