Chapter 5, Problem 5.61P

A heat pump operates between temperature ranges of 100 C and 250 C. Find its COP. What will be its efficiency if the heat engine operates in the same temperature range?

SL-4 A reversible refrigerator is driven by a (non-reversible) heat engine with e-0.250. Both operate between two heat reservoirs at 300K and 450K. The power output of the engine is 5,000W, which is the entire power input to the refrigerator. a) Write down or calculate the magnitudes of the Wk, Qhe and Q. for one second of operation of the b) Write down or calculate the magnitudes of the Wk, Qn, and Q. for one second of operation of the refrigerator. c) Calculate the magnitudes of the Wkest, Qhnet, and Qenet for one second of operation of the system. d) Show on a diagram like the one above for problem SL-1 the energy flow for the engine and refrigerator individually on the left and the net energy flow for the engine-refrigerator system on the right. e) Does this net result violate the second law of thermodynamics? EXPLAIN your answes. 2.

1.) A Carnot engine is coupled to a Carnot refrigerator so that all the work produced by the engine is used by the refrigerator in extraction of heat from a heat reservoir at 270K at the rate of 4 kJ/s. The source of energy for the Carnot engine is a heat reservoir at 500K. If both devise discard heat to the surrounding at 300K, a. How much heat does the engine absorb from the 500K reservoir? b. If the actual efficiency of the engine is n= Ncarnot /1.5 and the COP = COPCarnot/1.5, how much heat does the engine absorb from the 5O0K reservoir?