Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 11.10, Problem 17P
A refrigerator uses refrigerant-134a as the working fluid and operates on the ideal vapor-compression refrigeration cycle except for the compression process. The refrigerant enters the evaporator at 120 kPa with a quality of 34 percent and leaves the compressor at 70°C. If the compressor consumes 450 W of power, determine (a) the mass flow rate of the refrigerant, (b) the condenser pressure, and (c) the COP of the refrigerator.
FIGURE P11–17
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
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
3. A refrigerator uses refrigerant-134a as the working fluid and operates on the ideal vapor-
compression refrigeration cycle except for the compression process. The refrigerant enters
the evaporator at 120 kPa with a quality of 34 percent and leaves the compressor at 70°C. If
the compressor consumes 450 W of power, determine (a) the mass flow rate of the
refrigerant, (b) the condenser pressure, and (c) the COP of the refrigerator. Answers: (a)
0.00644 kg/s, (b) 800 kPa, (c) 2.03
|↓
Condenser
Expansion
valve
120 kPa
x=0.34
Evaporator
M
Warm
environment
70°C
Compressor
Cold
environment
A refrigerator uses refrigerant-134a as its working fluid and operates on the ideal vapor-compression refrigeration cycle. The
refrigerant evaporates at 5.00°F and condenses at 180 psia. This unit serves a 45000 Btu/h cooling load. Determine the mass flow rate
of the refrigerant and the power that this unit will require. (Take the required values from saturated refrigerant-134a tables.) (Round the
final answers to three decimal places.)
The mass flow rate of the refrigerant is
Ibm/h, and the power requirement is
kW.
Chapter 11 Solutions
Thermodynamics: An Engineering Approach
Ch. 11.10 - Why do we study the reversed Carnot cycle even...Ch. 11.10 - Why is the reversed Carnot cycle executed within...Ch. 11.10 - A steady-flow Carnot refrigeration cycle uses...Ch. 11.10 - Refrigerant-134a enters the condenser of a...Ch. 11.10 - Does the ideal vapor-compression refrigeration...Ch. 11.10 - Why is the throttling valve not replaced by an...Ch. 11.10 - In a refrigeration system, would you recommend...Ch. 11.10 - Does the area enclosed by the cycle on a T-s...Ch. 11.10 - Consider two vapor-compression refrigeration...Ch. 11.10 - It is proposed to use water instead of...
Ch. 11.10 - The COP of vapor-compression refrigeration cycles...Ch. 11.10 - A 10-kW cooling load is to be served by operating...Ch. 11.10 - An ice-making machine operates on the ideal...Ch. 11.10 - An air conditioner using refrigerant-134a as the...Ch. 11.10 - An ideal vapor-compression refrigeration cycle...Ch. 11.10 - A refrigerator operates on the ideal...Ch. 11.10 - A refrigerator uses refrigerant-134a as the...Ch. 11.10 - An ideal vapor-compression refrigeration cycle...Ch. 11.10 - A refrigerator uses refrigerant-134a as its...Ch. 11.10 - A refrigerator uses refrigerant-134a as the...Ch. 11.10 - A commercial refrigerator with refrigerant-134a as...Ch. 11.10 - The manufacturer of an air conditioner claims a...Ch. 11.10 - Prob. 24PCh. 11.10 - How is the second-law efficiency of a refrigerator...Ch. 11.10 - Prob. 26PCh. 11.10 - Prob. 27PCh. 11.10 - Prob. 28PCh. 11.10 - Bananas are to be cooled from 28C to 12C at a rate...Ch. 11.10 - A vapor-compression refrigeration system absorbs...Ch. 11.10 - A room is kept at 5C by a vapor-compression...Ch. 11.10 - Prob. 32PCh. 11.10 - A refrigerator operating on the vapor-compression...Ch. 11.10 - When selecting a refrigerant for a certain...Ch. 11.10 - A refrigerant-134a refrigerator is to maintain the...Ch. 11.10 - Consider a refrigeration system using...Ch. 11.10 - A refrigerator that operates on the ideal...Ch. 11.10 - A heat pump that operates on the ideal...Ch. 11.10 - Do you think a heat pump system will be more...Ch. 11.10 - What is a water-source heat pump? How does the COP...Ch. 11.10 - A heat pump operates on the ideal...Ch. 11.10 - Refrigerant-134a enters the condenser of a...Ch. 11.10 - A heat pump that operates on the ideal...Ch. 11.10 - The liquid leaving the condenser of a 100,000...Ch. 11.10 - Reconsider Prob. 1144E. What is the effect on the...Ch. 11.10 - A heat pump using refrigerant-134a heats a house...Ch. 11.10 - A heat pump using refrigerant-134a as a...Ch. 11.10 - Reconsider Prob. 1148. What is the effect on the...Ch. 11.10 - Prob. 50PCh. 11.10 - How does the COP of a cascade refrigeration system...Ch. 11.10 - Consider a two-stage cascade refrigeration cycle...Ch. 11.10 - Can a vapor-compression refrigeration system with...Ch. 11.10 - Prob. 54PCh. 11.10 - A certain application requires maintaining the...Ch. 11.10 - Prob. 56PCh. 11.10 - Repeat Prob. 1156 for a flash chamber pressure of...Ch. 11.10 - Prob. 59PCh. 11.10 - A two-stage compression refrigeration system with...Ch. 11.10 - A two-stage compression refrigeration system with...Ch. 11.10 - A two-evaporator compression refrigeration system...Ch. 11.10 - A two-evaporator compression refrigeration system...Ch. 11.10 - Repeat Prob. 1163E if the 30 psia evaporator is to...Ch. 11.10 - Consider a two-stage cascade refrigeration cycle...Ch. 11.10 - How does the ideal gas refrigeration cycle differ...Ch. 11.10 - Prob. 67PCh. 11.10 - Devise a refrigeration cycle that works on the...Ch. 11.10 - How is the ideal gas refrigeration cycle modified...Ch. 11.10 - Prob. 70PCh. 11.10 - How do we achieve very low temperatures with gas...Ch. 11.10 - An ideal gas refrigeration system operates with...Ch. 11.10 - Air enters the compressor of an ideal gas...Ch. 11.10 - Repeat Prob. 1173 for a compressor isentropic...Ch. 11.10 - An ideal gas refrigeration cycle uses air as the...Ch. 11.10 - Rework Prob. 1176E when the compressor isentropic...Ch. 11.10 - A gas refrigeration cycle with a pressure ratio of...Ch. 11.10 - A gas refrigeration system using air as the...Ch. 11.10 - An ideal gas refrigeration system with two stages...Ch. 11.10 - Prob. 81PCh. 11.10 - Prob. 82PCh. 11.10 - What are the advantages and disadvantages of...Ch. 11.10 - Prob. 84PCh. 11.10 - Prob. 85PCh. 11.10 - Prob. 86PCh. 11.10 - Prob. 87PCh. 11.10 - Heat is supplied to an absorption refrigeration...Ch. 11.10 - An absorption refrigeration system that receives...Ch. 11.10 - An absorption refrigeration system receives heat...Ch. 11.10 - Heat is supplied to an absorption refrigeration...Ch. 11.10 - Prob. 92PCh. 11.10 - Prob. 93PCh. 11.10 - Consider a circular copper wire formed by...Ch. 11.10 - An iron wire and a constantan wire are formed into...Ch. 11.10 - Prob. 96PCh. 11.10 - Prob. 97PCh. 11.10 - Prob. 98PCh. 11.10 - Prob. 99PCh. 11.10 - Prob. 100PCh. 11.10 - Prob. 101PCh. 11.10 - Prob. 102PCh. 11.10 - A thermoelectric cooler has a COP of 0.18, and the...Ch. 11.10 - Prob. 104PCh. 11.10 - Prob. 105PCh. 11.10 - Prob. 106PCh. 11.10 - Rooms with floor areas of up to 15 m2 are cooled...Ch. 11.10 - Consider a steady-flow Carnot refrigeration cycle...Ch. 11.10 - Consider an ice-producing plant that operates on...Ch. 11.10 - A heat pump that operates on the ideal...Ch. 11.10 - A heat pump operates on the ideal...Ch. 11.10 - A large refrigeration plant is to be maintained at...Ch. 11.10 - Repeat Prob. 11112 assuming the compressor has an...Ch. 11.10 - An air conditioner with refrigerant-134a as the...Ch. 11.10 - A refrigerator using refrigerant-134a as the...Ch. 11.10 - Prob. 117RPCh. 11.10 - An air conditioner operates on the...Ch. 11.10 - Consider a two-stage compression refrigeration...Ch. 11.10 - A two-evaporator compression refrigeration system...Ch. 11.10 - The refrigeration system of Fig. P11122 is another...Ch. 11.10 - Repeat Prob. 11122 if the heat exchanger provides...Ch. 11.10 - An aircraft on the ground is to be cooled by a gas...Ch. 11.10 - Consider a regenerative gas refrigeration cycle...Ch. 11.10 - An ideal gas refrigeration system with three...Ch. 11.10 - Prob. 130RPCh. 11.10 - Derive a relation for the COP of the two-stage...Ch. 11.10 - Prob. 133FEPCh. 11.10 - Prob. 134FEPCh. 11.10 - Prob. 135FEPCh. 11.10 - Prob. 136FEPCh. 11.10 - Prob. 137FEPCh. 11.10 - An ideal vapor-compression refrigeration cycle...Ch. 11.10 - Prob. 139FEPCh. 11.10 - An ideal gas refrigeration cycle using air as the...Ch. 11.10 - Prob. 141FEPCh. 11.10 - Prob. 142FEP
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
For the beam loading of Figure P334, draw the complete shearing force and bending moment diagrams, and determin...
Machine Elements in Mechanical Design (6th Edition) (What's New in Trades & Technology)
Describe the structural changes that take place when a plain-carbon eutectoid steel is slowly cooled from the a...
Foundations of Materials Science and Engineering
Select a mechanical component from Part 3 of this book (roller bearings, springs, etc.), go to the Internet, an...
Shigley's Mechanical Engineering Design (McGraw-Hill Series in Mechanical Engineering)
A nozzle at A discharges water with an initial velocity of 36 ft/s at an angle with the horizontal. Determine ...
Vector Mechanics for Engineers: Dynamics
What is the weight in newtons of an object that has a mass of (a) 8 kg, (b) 0.04 kg, (c) 760 Mg?
Statics and Mechanics of Materials (5th Edition)
List several uses of the arbor press.
Machine Tool Practices (10th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- 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.arrow_forwardA refrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapourcompression refrigeration cycle between 0.12 MPa and 0.7 MPa. The mass flow rate of therefrigerant is 0.05 kg/s. Show the cycle on a T-s diagram with respect to saturation lines.Determine;(a) The rate of heat removal from the refrigerated space and the power input to thecompressor,(b) The rate of heat rejection to the environment, and(c) The coefficient of performance.arrow_forwardA vapor-compression refrigeration system circulates refrigerant 134a at a rate of 0.15 kg/s. The refrigerant enters the compressor at -10 degrees Celcius and 100 kPa, and exits the compressor at 800 kPa. The isentropic efficiency of the compressor is 76%. Pressure drop through the condenser and evaporator are negligible. The refrigerant exits the condenser at 30 degrees Celcius and 800 kPa. Ignoring the heat transfer between the compressor and its surroundings, determine: The rate at which heat energy is removed from the refrigerated space in kW. The coefficient of perfromance.arrow_forward
- Refrigerant-134a enters the compressor of a cooling system as superheated vapor at 0.18 MPa and 0°C with a flow rate of 0.15 kg/s. It exits the compressor at 0.8 MPa and 60°C. Post compression, the refrigerant is cooled in the condenser to 28°C and 1.4 MPa. Subsequently, it's throttled to 0.16 MPa. Neglecting any heat transfer and pressure drops in the pipelines between the components, represent the cycle on a T-s diagram concerning saturation lines. Calculate: (a) The rate of heat extraction from the cooling area and the energy input to the compressor. (b) The isentropic efficiency of the compressor. (c) The Coefficient of Performance (COP) of the cooling system.arrow_forwardA heat pump uses R-134a as the refrigerant. The refrigerant enters the adiabatic compressor as saturated vapor at 120 kPa and exits it (the compressor) at 800 kPa and 50°C. The refrigerant exits the condenser as saturated liquid at 800 kPa. Then, the refrigerant flows through an adiabatic expansion valve, reducing the pressure back to the evaporator pressure of 120 kPa. The compressor power is 1.25 kW. a) Calculate the mass flow rate of the refrigerant (R-134a) in kg/s or g/s. b) Calculate the heat power delivered from the condenser in kW. c) Calculate the coefficient of performance (COP) of the heat pump, COP_HP.d) Calculate the refrigerant’s vapor quality entering the evaporator.arrow_forwardConsider a 332 kJ/min refrigeration system that operates on an ideal vapor-compression refrigeration cycle with refrigerant-134a as the working fluid. The refrigerant enters the compressor as saturated vapor at 140 kPa and is compressed to 800 kPa. Determine the power input to the compressor in kW.arrow_forward
- Consider an actual vapor-compression refrigeration cycle. R-134a enters the compressor as superheated vapor at 0.18 MPa and -10°C at a rate of 0.055 kg/s, and it leaves at 1.2 MPa and 60°C. The refrigerant is cooled in the condenser to 42°C and 1.15 MPa, and it is throttled to 0.22 MPa. Determine the rate of heat addition to the evaporator, in kW.arrow_forwardA gas refrigeration cycle with a pressure ratio of 3 uses helium as the working fluid. The temperature of the helium is -10°C at the compressor inlet and 50°C at the turbine inlet. Assuming adiabatic efficiencies of 80 percent for both the turbine and the compressor, determine (a) the minimum temperature in the cycle, (b) the coefficient of performance, and (c) the mass flow rate of the helium for a refrigeration rate of 18 kW.arrow_forwardA geothermal heat pump running a simple heat pump cycle uses R-134a as the refrigerant and sources thermal energy from well water. The well water enters the evaporator at 13°C and exits at 7°C, with negligible pressure drop. On the refrigerant side, the evaporator operates isobarically at 320 kPa and the refrigerant exits the evaporator at 10°C. The refrigerant is compressed to 1200 kPa through the compressor, which has an isentropic efficiency of 90%. In the condenser, air absorbs energy from the refrigerant at a rate of 4.5 tons (1 ton = 211 kJ/min) as its temperature increases from 22°C at the condenser inlet to 42°C at the condenser outlet. The condenser operates isobarically, and the refrigerant exits the condenser at 20°C. Calculate the input power to the compressor and the COP of the heat pump.arrow_forward
- A refrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 0.12 and 0.7 MPa at a rate of 0.05 kg/s. Show the cycle on a T-s diagram with respect to saturation lines. Determine (a)the rate of heat removal from the refrigerated space and the power input to the compressor, (b)the rate of heat rejection to the environment, (c)the coefficient of performance.arrow_forwardA refrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapor compression refrigeration cycle between 0.18 and 0.7 MPa. The mass flow rate of the refrigerant is 72.4 g/s. Determine the power input to the compressor (in kW). Do not answer in image formatarrow_forwardA 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.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage Learning
Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning
The Refrigeration Cycle Explained - The Four Major Components; Author: HVAC Know It All;https://www.youtube.com/watch?v=zfciSvOZDUY;License: Standard YouTube License, CC-BY