Question

In: Mechanical Engineering

5. A power cycle receives energy QH by heat transfer from a high temperature energy source...

5. A power cycle receives energy QH by heat transfer from a high temperature energy source at TH = 2000 K and rejects energy QL by heat transfer to a low temperature energy sink at TL = 400 K. For each of the following cases determine whether the cycle operate reversibly, irreversibly, or is impossible.

(a) QH = 1200 kJ, Wcycle = 1020 kJ.

(b) QH = 1200 kJ, QL = 240 kJ.

(c) Wcycle = 1400 kJ, QL = 600 kJ.

(d) efficiency = 40%.

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