With ph, ts diagram A refrigerator based on ideal vapor compression cycle operates between the temperature limits of -20 deg C and 40 deg C . The refrigerant enters the condenser as saturated vapor and leaves as saturated liquid . The enthalpy and entropy values for saturated liquid and vapor at these temperatures are given in the table below: T(OC) hf (KJ/kg) hg (KJ/kg) Sf (KJ/kg.K) Sg (KJ/kg.K) -20 20 180 0.07 0.7366 40 80 200 0.3 0.67 If the circulation rate of the refrigerant is 0.025 kg/sec , the refrigeration effect is equal to A) 1.2 kW B) 2.5 kW C) 3.2 kW D) 2.1 kW

With ph, ts diagram A refrigerator based on ideal vapor compression cycle operates between the temperature limits of -20 deg C and 40 deg C . The refrigerant enters the condenser as saturated vapor and leaves as saturated liquid . The enthalpy and entropy values for saturated liquid and vapor at these temperatures are given in the table below: T(OC) hf (KJ/kg) hg (KJ/kg) Sf (KJ/kg.K) Sg (KJ/kg.K) -20 20 180 0.07 0.7366 40 80 200 0.3 0.67 If the circulation rate of the refrigerant is 0.025 kg/sec , the refrigeration effect is equal to A) 1.2 kW B) 2.5 kW C) 3.2 kW D) 2.1 kW

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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