2. THE EVENTS OF A CASCADE, A PLIT-STAGE, LOW-TEMPERATURE REFRIGERATING CYCLE ARE AS FOLLOWS: AN AMMONIA VAPOR COMPRESSION SYSTEM OPERATES BETWEEN - 10C AND 33C WITH SATURATED LIQUID ON THE HIGH SIDE OF THE EXPANSION VALVE AND SATURATED VAPOR ENTERING THE COMPRESOR WHOSE VOLUMETRIC EFFICIENCY iS 89%. A R-11 COMPRESSION SYSTEM OPERATES BETWEEN -25C AND OC WITH SATURATED LIQUID ENTERING THE EXPANSION VALVE AND SATURATED VAPOR ENTERING THE COMPRESSOR WHOSE VOLUMETRIC EFFICIENCY IS 85%. THE AMMONIA EVAPORATOR SERVES AS THE CONDENSER OF THE R-11. FOR THE IDEAL CYCLE AND 10KW OF REFRIGERATION, FIND (a) THE DISPLACEMENT RATE OF EACH COMPRESSOR, AND (b) THE TOTAL ACTUAL POWER REQUIRED FOR COMPRESSION EFFICIENCIES OF 85%.

2. THE EVENTS OF A CASCADE, A PLIT-STAGE, LOW-TEMPERATURE REFRIGERATING CYCLE ARE AS FOLLOWS: AN AMMONIA VAPOR COMPRESSION SYSTEM OPERATES BETWEEN - 10C AND 33C WITH SATURATED LIQUID ON THE HIGH SIDE OF THE EXPANSION VALVE AND SATURATED VAPOR ENTERING THE COMPRESOR WHOSE VOLUMETRIC EFFICIENCY iS 89%. A R-11 COMPRESSION SYSTEM OPERATES BETWEEN -25C AND OC WITH SATURATED LIQUID ENTERING THE EXPANSION VALVE AND SATURATED VAPOR ENTERING THE COMPRESSOR WHOSE VOLUMETRIC EFFICIENCY IS 85%. THE AMMONIA EVAPORATOR SERVES AS THE CONDENSER OF THE R-11. FOR THE IDEAL CYCLE AND 10KW OF REFRIGERATION, FIND (a) THE DISPLACEMENT RATE OF EACH COMPRESSOR, AND (b) THE TOTAL ACTUAL POWER REQUIRED FOR COMPRESSION EFFICIENCIES OF 85%.

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

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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Similar questions

Refrigerators currently being manufactured in the United States are using______as their refrigerant.
Condensers in these refrigerators are all_______cooled.
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As shown below, a refrigeration cycle condenses a flow of ammonia from a saturated vapor at 4 barto a saturated liquid. The entering volumetric flow rate of the ammonia is 0.1 m3/s. The ammonia functions asthe cold reservoir for the refrigeration cycle, and the hot reservoir is at 25 ∘C. A faded specification sheet for therefrigeration cycle reads that the required power input is 35 kW.(a) Is this cycle possible? Why or why not?(b) If the cycle is impossible, how much work input is required to make the cycle
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