Question 3 In a vapour-compression refrigeration system, refrigerant - 134a enters the compressor superheated at 200 kPa and - 5 °C. The refrigerant enters the condenser at 1.4 MPa and 75 °C, and exits at 1.4 MPa as a saturated liquid. There is no significant heat transfer between the compressor and its surroundings, and the refrigerant passes through the evaporator with a negligible change in pressure. If the refrigerating capacity is 105 kW, represent the cycle on a T-s diagram and determine: a) the mass flow rate of the refrigerant in kg/s, b) the power input to the compressor in kW, c) the coefficient of performance, and (2) d) the isentropic compressor efficiency

Question 3 In a vapour-compression refrigeration system, refrigerant - 134a enters the compressor superheated at 200 kPa and - 5 °C. The refrigerant enters the condenser at 1.4 MPa and 75 °C, and exits at 1.4 MPa as a saturated liquid. There is no significant heat transfer between the compressor and its surroundings, and the refrigerant passes through the evaporator with a negligible change in pressure. If the refrigerating capacity is 105 kW, represent the cycle on a T-s diagram and determine: a) the mass flow rate of the refrigerant in kg/s, b) the power input to the compressor in kW, c) the coefficient of performance, and (2) d) the isentropic compressor efficiency

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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Why is two-stage compression popular for extra-low-temperature refrigeration systems?
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