Two engines are connected in series such that engine 1 operates between temperatures T₁ and Tm with T1 > Tm while engine 2 operates between temperatures Tm and T2 with Tm> T2. Engine 1 absorbs Q1 from heat bath at T1, performs work W₁, then dumps the remaining Qm to heat bath at Tm. Engine 2 absorbs the same dumped heat Qm from heat bath at Tm, performs work W2, then finally dumps the remaining Q2 into the heat bath at T2. Show that the effective efficiency of the two engines in series is given by, Eeff. 81 +82 -182, where 1 = W1/Q1 and 2 = W2/Qm. Suppose the two engines in series are reversible. Using the previous result, show that the effective efficiency is given by Eeff. = 1-T₂/T₁

Two engines are connected in series such that engine 1 operates between temperatures T₁ and Tm with T1 > Tm while engine 2 operates between temperatures Tm and T2 with Tm> T2. Engine 1 absorbs Q1 from heat bath at T1, performs work W₁, then dumps the remaining Qm to heat bath at Tm. Engine 2 absorbs the same dumped heat Qm from heat bath at Tm, performs work W2, then finally dumps the remaining Q2 into the heat bath at T2. Show that the effective efficiency of the two engines in series is given by, Eeff. 81 +82 -182, where 1 = W1/Q1 and 2 = W2/Qm. Suppose the two engines in series are reversible. Using the previous result, show that the effective efficiency is given by Eeff. = 1-T₂/T₁

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter44: Geothermal Heat Pumps

Section: Chapter Questions

Problem 13RQ: If 14 gpm of water is flowing through an open-loop heat pump with a temperature difference of 7F,...

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