An air refrigeration system having pressure ratio of 5 takes air at 0°C and 1 atm. It is compressed and then cooled to 19°C. A pressure drop of 5 kPa is measured in both cooler and refrigerator. If the efficiency of the compressor is 95% and that of the expander is 75%, determine the refrigeration capacity of the system TR, and the COP of the system if the flow of air is 7.5 kg/min. Assume compression and expansion processes to be isentropic.

An air refrigeration system having pressure ratio of 5 takes air at 0°C and 1 atm. It is compressed and then cooled to 19°C. A pressure drop of 5 kPa is measured in both cooler and refrigerator. If the efficiency of the compressor is 95% and that of the expander is 75%, determine the refrigeration capacity of the system TR, and the COP of the system if the flow of air is 7.5 kg/min. Assume compression and expansion processes to be isentropic.

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

Welded ______sealed compressors are normally used in household refrigerators.
Refrigerators currently being manufactured in the United States are using______as their refrigerant.
A refrigeration system is to be used to cool 45,000kg water for 32 Celsius to 19 Celsius in 5 hours. The refrigerant is R-134A and the operating condition are evaporating pressure 810 kPa and 1800 kPa liquefication pressure. Determine COP, quantity of cooling water in the condenser for an increase in temperature of 7 Celsius compressor power, volume of flow rate entering the compressor. With schematic diagram. Using this table https://www.docdroid.net/VkxK8WH/refrigerant-134a-pdf
For a 10 ton capacity refrigeration system, the pressure of refrigerant in the evaporator is 210 kPa, whereas in the condensor it is 900 kPa. If refrigerant R-134a is used under saturated conditions, calculate the theoritical power required to operate the compressor (kW)
A refrigeration system with a capacity of 15 tons of refrigeration, operates at 150 kPa in the evaporator, while in the condenser it is 1100 kPa. If R-134a refrigerant is in a saturated state, calculate the theoretical power required to operate the compressor. Compressor Power. Answer in kW
In an ammonia refrigerator , the pressure in the evaporator is 267. 58 KPa and theammonia at is 0.14 dry while at the exit is 0.86 dry . During compression the work done per kgof ammonia is 20 ,000 kg .m . Calculate volume of the vapor entering the compressor per minuteif the rate of ammonia circulation is 6.54 kg. The compressor has a volumetric efficiency of 90%and it runs at 150 rpm .The ratio of stroke to bore is 1 .Latent enthalpy of ammonia at basedon its evaporating pressure is 320 Kcal per kg and its latent specific volume of ammonia basedon its evaporating pressure is 0.436 m3 per kg .Specific volume of ammonia .A) 2.23 C) 2.46B) 3.23 D) 4.62
An ammonia refrigeration compressor takes its suction from the evaporator, at a temperature of-200F and a quality of 95%. The compressor discharges at a pressure of 100 psi, liquid ammonia leaves the condenser at 500F.(a)Determine the heat absorbed by the evaporator in kJ/kg. (b)Determine the heat rejected to the condenser in kJ/kg. (c)Determine the COP. (d)Determine the horsepower per ton of refrigeration. (e)Determine the quality of refrigerant upon entering to the evaporator
A vapor compression refrigeration systemhas an enthalpy of saturated liquid at the hightemperature side is 341.769 kJ/kg while at lowtemperature side is 131.27 kJ/kg and a latentheat of vaporization of 1312.63 kJ/kg. If themass flow rate of refrigerant is 0.50 kg/s.compute the tons of refrigeration.
For a 15 ton capacity refrigeration system, the pressure of refrigerant in the evaporator is 150 kPa, whereas in the condenser it is 1380 kPa. If ammonia (R-717) is used under saturated conditions, calculate the theoretical power required to operated the compressor (kW)
A simple air cooled system is used for an aero plane to take a load of 10 tons.Atmospheric temperature and pressure is 25°C and 0.9 atm respectively. Dueto ramming the pressure of air is increased from 0.9 atm, to 1 atm. The pressureof air leaving the main compressor is 3.5 atm and its 50% heat is removed inthe air-cooled heat exchanger and then it is passed through a evaporator for future cooling. The temperature of air is reduced by 10°C in the evaporator.Lastly the air is passed through cooling turbine and is supplied to the coolingcabin where the pressure is 1.03 atm. Assuming isentropic efficiency of the compressor and turbine are 75% and 70%,find i) Power required to take the load in the cooling cabinii) COP of the system.The temperature of air leaving the cabin should not exceed 25°C
Show also the P-s and T-s diagram. Catalogue data for R-134A compressor with a displacement of 75 L/s show the capacity to be 8 tons when the suction conditions are 0.1 MPa and -20°C and condensing temperature is 50°C. The refrigerant leaves the condenser as saturated liquid. Calculate the actual volumetric efficiency and the brake work of the compressor if the compressor efficiency is 70%
a cooling system with a capacity of 10 tons of refrigeration, operates at 210 kPa in the evaporator, while in the condenser is 1100 kPa. if refrigerant R-717 is saturated, calculate the theoretical power required to operate the compressor. compressor power = .... kW