REFRIGERATION ENGINEERING (!)USE SHAPIRO AND MORAN TABLE 3. A refrigerated room is kept at -35°C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejectedto cooling water that enters the condenser at 16°C at a rate of 0.45 kg/s and leaves 26°C. The refrigerant entersthe condenser at 1.2 MPa and 50°C and leaves at the same pressure sub-cooled by 5°C. If the compressorconsumes 74 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigerant load, (c) thecoefficient of performance and, (d) the minimum power input to the compressor for the same refrigerant load.

Given: Room temperature TL=-35 oC Refrigerant-R-134 Tw1=16oC Tw2=26oC mw=0.45 kg/s P1=1.2 MPa…

A refrigerated room is kept at -35°C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejecte to cooling water that enters the condenser at 16°C at a rate of 0.45 kg/s and leaves 26°C. The refrigerant enter the condenser at 1.2 MPa and 50°C and leaves at the same pressure sub-cooled by 5°C. If the compresso consumes 74 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigerant load, (c) the coefficient of performance and, (d) the minimum power input to the compressor for the same refrigerant load.

A refrigerated room is kept at -35°C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejecte to cooling water that enters the condenser at 16°C at a rate of 0.45 kg/s and leaves 26°C. The refrigerant enter the condenser at 1.2 MPa and 50°C and leaves at the same pressure sub-cooled by 5°C. If the compresso consumes 74 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigerant load, (c) the coefficient of performance and, (d) the minimum power input to the compressor for the same refrigerant load.

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

See similar textbooks

Similar questions

Refrigerators currently being manufactured in the United States are using______as their refrigerant.
Condensers in these refrigerators are all_______cooled.
A refrigerated room is kept at −18◦C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejected to cooling water that enters the condenser at 14◦C at a rate of 0.35 kg/s and leaves at 22◦C. The refrigerant enters the condenser at 1.2MPa and 50◦C and leaves at the same pressure subcooled by 5◦C. If the compressor consumes 5.5 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load and the COP, (c) the second-law efficiency of the refrigerator and the total exergy destruction in the cycle, and (d) the exergy destruction in the condenser. Take specific heat of water to be 4.18 kJ/kg·◦C.
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at –30°C by rejecting its waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 65°C and leaves at 42°C. The inlet state of the compressor is 60 kPa and –34°C and the compressor is estimated to gain a net heat of 450 W from the surroundings. Determine the theoretical maximum refrigeration load for the same power input to the compressor. Water 26°C ↑ 18°C 1.2 MPа 42°C 65°C Condenser Expansion Win valve Evaporator Compressor 60 kPa -34°C
Consider a refrigrator that operates on the vapor compression refrigeration cycle with R-134a as the working fluid. The refrigerant enters the compressor as saturated vapor at 70 kPa, and exits at 1200 kPa and 90°C, and leaves the condenser as saturated liquid at 1200 kPa. The coefficient of performance of this refrigrator is
An ideal vapor-compression refrigeration cycle uses R-134a as the refrigerant. The refrigerant enters the evaporator at 160 kpa with a quality of 25% and leaves the compressor at 65 °C. If the compressor consumes 800W of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the COP of the refrigerator
A refrigerated room is kept at -27°C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejected to cooling water that enters the condenser at 16°C at a rate of 0.22 kg/s and leaves at 23 °C. The refrigerant enters the condenser at 1.2 MPa and 65 °C and leaves at 42°C. The inlet state of the compressor is 60 kPa and -34 °C and the compressor is estimated to gain a net heat of 150 W from the surroundings. Determine (a) the quality of the refrigerant at the evaporator inlet, (b) the refrigeration load, (c) the COP of the refrigerator, and (d) the theoretical maximum refrigeration load for the same power input to the compressor.
Consider a refrigerator that operates on the vapor compression refrigeration cycle with R-134a as the working fluid. The refrigerant enters the compressor as a saturated vapor at 140 kPa, and exits at 800 kPa and 60 degrees Celsius, and leaves the condenser as a saturated liquid at 800 kPa. The COP of this refrigerator is:
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -30°C by rejecting its waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 65°C and leaves at 42°C. The inlet state of the compressor is 60 kPa and -34 °C and the compressor is estimated to gain a net heat of 450 W from the surroundings. Determine (a) the quality of the refrigerant at the evaporator inlet (b) the refrigeration load in kW (c) the COP of the refrigerator (d) the theoretical maximum refrigeration load in kW for the same power input to the compressor. To obtain enthalpy values on the cooling water use steam tables.
Consider a heat pump that operates on the vapor compression refrigeration cycle with R-134a as the working fluid. The refrigerant enters the compressor as saturated vapor at 180 kPa, and exits at 900 kPa and 40°C, and leaves the condenser as saturated liquid at 900 kPa. The coefficient of performance of this heat pump is a. 5.51 b. 4.58 c. 3.61 d. 4.06 e. 2.87
A refrigeration system with R134a as the working fluid is used to maintain a space at 25°C by absorbing heat from water entering the evaporator at 50°C with atmospheric pressure at a rate of 0.065kg/s and exiting at 40°C. The compression has an isentropic efficiency of 75%. The refrigerant exits the evaporator at 20°C with 0.5542 MPa, while the condenser outlet temperature is 3.8°C. The heat exchange in the evaporator is 2.717 kW that was the result I obtained, so how do I analyze the effect of the isentropic compression efficiency on the process? I need help please, I am stuck on this homework.
A refrigeration system with R134a as the working fluid is used to maintain a space at 25°C by absorbing heat from water entering the evaporator at 50°C with atmospheric pressure at a rate of 0.065kg/s and exiting at 40°C. The compression has an isentropic efficiency of 75%. The refrigerant exits the evaporator at 20°C with 0.5542 MPa, while the condenser outlet temperature is 3.8°C. The heat exchange in the evaporator is 2.717 kW that was the result I obtained, so what would be the result of the isentropic efficiency of compression on the process? I need help please, I am stuck on this homework.