Thermodynamics: An Engineering Approach
8th Edition
ISBN: 9780073398174
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Videos
Question
Chapter 11.10, Problem 27P
To determine
The power input, the COP of the cycle, and the second law efficiency of the system.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A vapor compression refrigeration system is designed to have a capacity of 100 tons of refrigeration. It produces chilled water from 23C to 2C. Its actual coefficient of performance is 5.96 and 35% of the power supplied to the compressor is lost in the form of friction and cylinder cooling losses. Determine the condenser cooling water required in kg/s for temperature rise of 10C.
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 typical 200-m2 house can be cooled adequately by a 3.5-ton air conditioner whose COP is 4.0. Determine the rate of heat gain of the house when the air conditioner is running continuously to maintain a constant temperature in the house.
Chapter 11 Solutions
Thermodynamics: An Engineering Approach
Ch. 11.10 - Why is the reversed Carnot cycle executed within...Ch. 11.10 - Why do we study the reversed Carnot cycle even...Ch. 11.10 - 11–3 A steady-flow Carnot refrigeration cycle uses...Ch. 11.10 - Does the ideal vapor-compression refrigeration...Ch. 11.10 - Why is the throttling valve not replaced by an...Ch. 11.10 - It is proposed to use water instead of...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 - The COP of vapor-compression refrigeration cycles...
Ch. 11.10 - An ice-making machine operates on the ideal...Ch. 11.10 - A 10-kW cooling load is to be served by operating...Ch. 11.10 - 11–13 An ideal vapor-compression refrigeration...Ch. 11.10 - 11–14 Consider a 300 kJ/min refrigeration system...Ch. 11.10 - 11–16 Repeat Prob. 11–14 assuming an isentropic...Ch. 11.10 - 11–17 Refrigerant-134a enters the compressor of a...Ch. 11.10 - A commercial refrigerator with refrigerant-134a as...Ch. 11.10 - 11–19 Refrigcrant-134a enters the compressor of a...Ch. 11.10 - A refrigerator uses refrigerant-134a as the...Ch. 11.10 - The manufacturer of an air conditioner claims a...Ch. 11.10 - Prob. 23PCh. 11.10 - How is the second-law efficiency of a refrigerator...Ch. 11.10 - Prob. 25PCh. 11.10 - Prob. 26PCh. 11.10 - Prob. 27PCh. 11.10 - 11–28 Bananas are to be cooled from 28°C to 12°C...Ch. 11.10 - A vapor-compression refrigeration system absorbs...Ch. 11.10 - A refrigerator operating on the vapor-compression...Ch. 11.10 - A room is kept at 5C by a vapor-compression...Ch. 11.10 - Prob. 32PCh. 11.10 - 11–33 A refrigeration system operates on the ideal...Ch. 11.10 - When selecting a refrigerant for a certain...Ch. 11.10 - Consider a refrigeration system using...Ch. 11.10 - A refrigerant-134a refrigerator is to maintain the...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 - Prob. 42PCh. 11.10 - Refrigerant-134a enters the condenser of a...Ch. 11.10 - Prob. 45PCh. 11.10 - A heat pump using refrigerant-134a heats a house...Ch. 11.10 - How does the COP of a cascade refrigeration system...Ch. 11.10 - A certain application requires maintaining the...Ch. 11.10 - Consider a two-stage cascade refrigeration cycle...Ch. 11.10 - Can a vapor-compression refrigeration system with...Ch. 11.10 - Prob. 52PCh. 11.10 - Prob. 53PCh. 11.10 - Repeat Prob. 1156 for a flash chamber pressure of...Ch. 11.10 - Prob. 56PCh. 11.10 - Prob. 57PCh. 11.10 - 11–58 Consider a two-stage cascade refrigeration...Ch. 11.10 - Prob. 59PCh. 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 - How does the ideal gas refrigeration cycle differ...Ch. 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. 66PCh. 11.10 - How do we achieve very low temperatures with gas...Ch. 11.10 - 11–68E Air enters the compressor of an ideal gas...Ch. 11.10 - Prob. 69PCh. 11.10 - Air enters the compressor of an ideal gas...Ch. 11.10 - Repeat Prob. 1173 for a compressor isentropic...Ch. 11.10 - Prob. 73PCh. 11.10 - Prob. 74PCh. 11.10 - Prob. 75PCh. 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. 78PCh. 11.10 - Prob. 79PCh. 11.10 - What are the advantages and disadvantages of...Ch. 11.10 - Prob. 81PCh. 11.10 - Prob. 82PCh. 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. 86PCh. 11.10 - Prob. 87PCh. 11.10 - Prob. 88PCh. 11.10 - Prob. 89PCh. 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. 92PCh. 11.10 - Prob. 93PCh. 11.10 - Prob. 94PCh. 11.10 - Prob. 95PCh. 11.10 - Prob. 96PCh. 11.10 - Prob. 97PCh. 11.10 - Prob. 98PCh. 11.10 - A thermoelectric cooler has a COP of 0.18, and the...Ch. 11.10 - Prob. 100PCh. 11.10 - Prob. 101PCh. 11.10 - Prob. 102PCh. 11.10 - Prob. 103RPCh. 11.10 - Prob. 104RPCh. 11.10 - Prob. 105RPCh. 11.10 - A heat pump that 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 - A heat pump operates on the ideal...Ch. 11.10 - An air conditioner with refrigerant-134a as the...Ch. 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 - Prob. 116RPCh. 11.10 - Prob. 117RPCh. 11.10 - Prob. 118RPCh. 11.10 - Consider a regenerative gas refrigeration cycle...Ch. 11.10 - Prob. 120RPCh. 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 ideal gas refrigeration system with three...Ch. 11.10 - Derive a relation for the COP of the two-stage...Ch. 11.10 - Prob. 129FEPCh. 11.10 - Prob. 130FEPCh. 11.10 - Prob. 131FEPCh. 11.10 - Prob. 132FEPCh. 11.10 - An ideal vapor-compression refrigeration cycle...Ch. 11.10 - Prob. 134FEPCh. 11.10 - An ideal gas refrigeration cycle using air as the...Ch. 11.10 - Prob. 136FEPCh. 11.10 - Prob. 137FEPCh. 11.10 - Prob. 138FEP
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
- Refrigerators currently being manufactured in the United States are using______as their refrigerant.arrow_forwardA chiller runs on R-410a as the working fluid. It operates with a condensing temperature of 45 C and an evaporating temperature of 0 C. It is determined to develop 85 kW of refrigeration. Calculate the following: (a)refrigerating effect, (b)flow rate of refrigeration, (c)power required by compressor, (d)coefficient of performance, (e)power per kilowatt of refrigeration, (f)theoretical horsepower input of the compressorarrow_forwardA refrigeration system absorbs heat from a space at 2 ◦C at a rate of 6.9 kW and rejects heatto water in the condenser. Water enters the condenser at 16 ◦C at a rate of 0.27 kg/s. The COPof the system is estimated to be 1.85. Determine (a) the power input to the system, (b) thetemperature of the water at the exit of the condenser, and (c) the second-law efficiency andthe exergy destruction for the refrigerator. Take the dead-state temperature to be the inlettemperature of water in the condenser. The specific heat of water is 4.18 kJ/kg·◦C.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. The mass flow rate of the refrigerant is 0.05 kg/s. Determine:a) the rate of heat removal from the refrigerated space (kW),b)the power input to the compressor (kW),c) the rate of heat rejection to the environment (kW), andd) the coefficient of performance.Submit your solution by multiplying (a)*(b)*(c)*(d) = _________.arrow_forwardA refrigerator uses refrigerant-134a as the working fluid and operates on an ideal vapor-compression refrigeration cycle between 0.12 and 0.7 MPa. The mass flow rate of the refrigerant is 0.05 kg/s. Determine: a) the rate of heat removal from the refrigerated space (kW), b)the power input to the compressor (kW), c) the rate of heat rejection to the environment (kW), and d) the coefficient of performance. Submit your solution by multiplying (a)*(b)*(c)*(d) =arrow_forwardA vapor compression refrigeration cycle operates at steady flow conditions with 0.25 kg/s or R-134a. The table below shows some of the operating parameters and properties for the refrigerant. The compressor is réfrigerated, and the condenser is also cooled with water. The compressor receives shaft power equivalent to 7.5 hp. Neglecting changes in kinetic and potential energy changes and any heat loss between devices, please answer the following. a. Complete the table below and sketch the cycle processes on a T-s diagram. When completing the table please use the same number of decimal places as in the tables. b. 123456 Determine the cooling capacity of the refrigeration unit, in Tons (1 refrigeration Ton=211 kJ/min). c. Compute the COP d. Determine the volume flow rate of refrigerant entering the condenser in L/min. e. Determine the mass flow rate of cooling water passing through the condenser. 1. Determine the heat transfer rate from the compressor. g. Compute the rate of entropy…arrow_forward
- A vapor compression refrigeration cycle operates at steady flow conditions with 0.25 kg/s or R-134a. The table below shows some of the operating parameters and properties for the refrigerant. The compressor is refrigerated, and the condenser is also cooled with water. The compressor receives shaft power equivalent to 7.5 hp. Neglecting changes in kinetic and potential energy changes and any heat loss between devices, please answer the following. a. Complete the table below and sketch the cycle processes on a T-s diagram. When completing the table please use the same number of decimal places as in the tables. 123456 b. Determine the cooling capacity of the refrigeration unit, in Tons (1 refrigeration Ton = 211 kJ/min). c. Compute the COP. d. Determine the volume flow rate of refrigerant entering the condenser in L/min. e. Determine the mass flow rate of cooling water passing through the condenser. f. Determine the heat transfer rate from the compressor. g. Compute the rate of entropy…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 refrigerating system having a 2-Stage Compression with Flash gas removal and intercooling (without water intercooler) operates under pressure limits of 1200kPa and 30kPa and uses R22 as a refrigerant. If the heat to be rejected by the condenser is equal to 185kJ/s and the COP of the system is 327%, determine the following: a.Total work of Compression in kW b. Individual work of compressor kW c.Refrigerating Effect in TOR d. Mass flowrate in the high-pressure and low-pressure loop of the system in kg/s e. Mass flow rate (kg/s) flowing in the high lower pressure loops of the systemarrow_forward
- Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 MPa and -10oC at rate of 0.05 kg/sec and leave at 0.8 MPa and 50oC. The refrigerant is cooled in the condenser to 26oC and 0.72MPa and is throttled to 0.15MPa. Determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, (b) the isentropic efficiency of the compressor and (c) the coefficient of performance.arrow_forwardA standard vapor compression system produces 70.4 kW of refrigeration using R-12as a refrigerant while operating between a condenser temperature of 42 °C and anevaporator temperature of –25 °C.2.1 Draw the p-h diagram of the cycle. 2.2 Determine:(a) the refrigerating effect in kJ/kg, (b) the circulating rate in kg/s, (c) the power supplied, (d) the COP, (e) the heat rejected in kW, and(f) the volume flow rate in m3/s.arrow_forwardAn ammonia compressor operates on an evaporator pressure of 291.57 kPa and a condenser pressure of 1557 kPa. A Heat Exchanger is installed thus superheating the refrigerant by 100C and a subcooling by 50 C. The system is used to cool water at 2 kg/s from 250 C to 150 C. Given: h1=1476 kJ/kg , h2=1752 kJ/kg . Determine the ff: a.) mass flow of reffrigerant. kg/s b.) compressor work. kw c.) mass flow of cooling water needed in the condenser for a temp. drop of 180F. kg/sarrow_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