P18. An ideal vapor-compression refrigeration cycle (i.e., evaporator, compressor, condenser and valve) operating at steady state within the temperature limits of 253 K and 313 K. The refrigerant enters the condenser as saturated vapor and leaves as saturated liquid. The values of enthalpy and entropy for saturated liquid and saturated vapor at these temperatures are shown in the below table. The COP of the refrigerator is P18 T (K) h; (k]/kg) hg (k]/kg) St (k]/kg K) Sg (k]/kg K) 253 40 150 0.07 0.7366 313 80 200 0.3 0.67 Select one: a. 2.12 b. 6.07 C.0.97 d. 3.62

P18. An ideal vapor-compression refrigeration cycle (i.e., evaporator, compressor, condenser and valve) operating at steady state within the temperature limits of 253 K and 313 K. The refrigerant enters the condenser as saturated vapor and leaves as saturated liquid. The values of enthalpy and entropy for saturated liquid and saturated vapor at these temperatures are shown in the below table. The COP of the refrigerator is P18 T (K) h; (k]/kg) hg (k]/kg) St (k]/kg K) Sg (k]/kg K) 253 40 150 0.07 0.7366 313 80 200 0.3 0.67 Select one: a. 2.12 b. 6.07 C.0.97 d. 3.62

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

Chapter41: Troubleshooting

Section: Chapter Questions

Problem 8RQ: When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a...

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