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
Textbook Question
Chapter 5.5, Problem 82P
The evaporator of a refrigeration cycle is basically a heat exchanger in which a refrigerant is evaporated by absorbing heat from a fluid. Refrigerant-22 enters an evaporator at 200 kPa with a quality of 22 percent and a flow rate of 2.65 L/h. R-22 leaves the evaporator at the same pressure superheated by 5°C. The refrigerant is evaporated by absorbing heat from air whose flow rate is 0.75 kg/s. Determine (a) the rate of heat absorbed from the air and (b) the temperature change of air. The properties of R-22 at the inlet and exit of the condenser are h1 = 220.2 kJ/kg, V1 = 0.0253 m3/kg, and h2 = 398.0 kJ/kg.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.22 MPa and 27 C at a rate of 0.07 kg/s, and it leaves at 1.2 MPa and 73°C. The refrigerant is cooled in the condenser to 44°C and 1.16 MPa, and t is throttied to 0.21 MPa. Disregarding any heat transfer and pressure drops in the connecting lines between the components, show the cycle on a T-s diagram with respect to saturation lines, and 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 COP of the refrigerator.
An 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/s
4. Steam enters the condenser of a steam power plant at 20000 kPa and a quality of 95 percent with a mass flow rate of 20 Mg/h. It is to be cooled by water from a nearby river in circulating the water through the tubes within the condenser. To prevent thermal pollution, the river water is not allowed to experience a temperature rise above 10oC. If the steam is to leave the condenser as saturated liquid at 20000 Pa, determine the mass flow rate of the cooling water required
Chapter 5 Solutions
Thermodynamics: An Engineering Approach
Ch. 5.5 - Name four physical quantities that are conserved...Ch. 5.5 - Define mass and volume flow rates. How are they...Ch. 5.5 - Does the amount of mass entering a control volume...Ch. 5.5 - Consider a device with one inlet and one outlet....Ch. 5.5 - The ventilating fan of the bathroom of a building...Ch. 5.5 - Air enters a 16-cm-diameter pipe steadily at 200...Ch. 5.5 - A steam pipe is to transport 200 lbm/s of steam at...Ch. 5.5 - A garden hose attached with a nozzle is used to...Ch. 5.5 - A steady-flow compressor is used to compress...Ch. 5.5 - Air enters the 1-m2 inlet of an aircraft engine at...
Ch. 5.5 - A 2-m3 rigid tank initially contains air whose...Ch. 5.5 - Air enters a nozzle steadily at 2.21 kg/m3 and 40...Ch. 5.5 - A spherical hot-air balloon is initially filled...Ch. 5.5 - Water enters the constant 130-mm inside-diameter...Ch. 5.5 - A desktop computer is to be cooled by a fan whose...Ch. 5.5 - A hair dryer is basically a duct of constant...Ch. 5.5 - Refrigerant-134a enters a 28-cm-diameter pipe...Ch. 5.5 - What are the different mechanisms for transferring...Ch. 5.5 - How do the energies of a flowing fluid and a fluid...Ch. 5.5 - An air compressor compresses 6 L of air at 120 kPa...Ch. 5.5 - A house is maintained at 1 atm and 24C, and warm...Ch. 5.5 - Refrigerant-134a enters the compressor of a...Ch. 5.5 - Steam is leaving a pressure cooker whose operating...Ch. 5.5 - How is a steady-flow system characterized?Ch. 5.5 - Can a steady-flow system involve boundary work?Ch. 5.5 - A diffuser is an adiabatic device that decreases...Ch. 5.5 - The kinetic energy of a fluid increases as it is...Ch. 5.5 - The stators in a gas turbine are designed to...Ch. 5.5 - The diffuser in a jet engine is designed to...Ch. 5.5 - Air enters a nozzle steadily at 50 psia, 140F, and...Ch. 5.5 - Air at 600 kPa and 500 K enters an adiabatic...Ch. 5.5 - Carbon dioxide enters an adiabatic nozzle steadily...Ch. 5.5 - Steam enters a nozzle at 400C and 800 kPa with a...Ch. 5.5 - Air at 80 kPa and 127C enters an adiabatic...Ch. 5.5 - Air at 13 psia and 65F enters an adiabatic...Ch. 5.5 - Refrigerant-134a at 700 kPa and 120C enters an...Ch. 5.5 - Refrigerant-134a enters a diffuser steadily as...Ch. 5.5 - Air at 80 kPa, 27C, and 220 m/s enters a diffuser...Ch. 5.5 - Air enters an adiabatic nozzle steadily at 300...Ch. 5.5 - Consider an adiabatic turbine operating steadily....Ch. 5.5 - Prob. 42PCh. 5.5 - Somebody proposes the following system to cool a...Ch. 5.5 - Air is expanded from 1000 kPa and 600C at the...Ch. 5.5 - Prob. 45PCh. 5.5 - Refrigerant-134a enters a compressor at 100 kPa...Ch. 5.5 - Refrigerant-134a enters a compressor at 180 kPa as...Ch. 5.5 - Steam flows steadily through an adiabatic turbine....Ch. 5.5 - Steam flows steadily through a turbine at a rate...Ch. 5.5 - Steam enters an adiabatic turbine at 8 MPa and...Ch. 5.5 - An adiabatic air compressor compresses 10 L/s of...Ch. 5.5 - Carbon dioxide enters an adiabatic compressor at...Ch. 5.5 - Steam flows steadily into a turbine with a mass...Ch. 5.5 - Air is compressed by an adiabatic compressor from...Ch. 5.5 - Air enters the compressor of a gas-turbine plant...Ch. 5.5 - A portion of the steam passing through a steam...Ch. 5.5 - Why are throttling devices commonly used in...Ch. 5.5 - Would you expect the temperature of air to drop as...Ch. 5.5 - During a throttling process, the temperature of a...Ch. 5.5 - Someone claims, based on temperature measurements,...Ch. 5.5 - Refrigerant-134a is throttled from the saturated...Ch. 5.5 - A saturated liquidvapor mixture of water, called...Ch. 5.5 - Prob. 64PCh. 5.5 - A well-insulated valve is used to throttle steam...Ch. 5.5 - Refrigerant-134a enters the expansion valve of a...Ch. 5.5 - Prob. 68PCh. 5.5 - Prob. 69PCh. 5.5 - Consider a steady-flow heat exchanger involving...Ch. 5.5 - Prob. 71PCh. 5.5 - Refrigerant-134a at 700 kPa, 70C, and 8 kg/min is...Ch. 5.5 - Hot and cold streams of a fluid are mixed in a...Ch. 5.5 - A hot-water stream at 80C enters a mixing chamber...Ch. 5.5 - Water at 80F and 20 psia is heated in a chamber by...Ch. 5.5 - An adiabatic open feedwater heater in an electric...Ch. 5.5 - Cold water (cp = 4.18 kJ/kgC) leading to a shower...Ch. 5.5 - Steam is to be condensed on the shell side of a...Ch. 5.5 - Air (cp = 1.005 kJ/kgC) is to be preheated by hot...Ch. 5.5 - An open feedwater heater heats the feedwater by...Ch. 5.5 - Refrigerant-134a at 1 MPa and 90C is to be cooled...Ch. 5.5 - The evaporator of a refrigeration cycle is...Ch. 5.5 - An air-conditioning system involves the mixing of...Ch. 5.5 - A well-insulated shell-and-tube heat exchanger is...Ch. 5.5 - Steam is to be condensed in the condenser of a...Ch. 5.5 - Steam is to be condensed in the condenser of a...Ch. 5.5 - Two streams of water are mixed in an insulated...Ch. 5.5 - Two mass streams of the same ideal gas are mixed...Ch. 5.5 - Water is heated in an insulated, constant-diameter...Ch. 5.5 - A 110-volt electrical heater is used to warm 0.3...Ch. 5.5 - The ducts of an air heating system pass through an...Ch. 5.5 - The fan on a personal computer draws 0.3 ft3/s of...Ch. 5.5 - Saturated liquid water is heated in a steady-flow...Ch. 5.5 - Water enters the tubes of a cold plate at 70F with...Ch. 5.5 - Prob. 96PCh. 5.5 - A computer cooled by a fan contains eight PCBs,...Ch. 5.5 - A desktop computer is to be cooled by a fan. The...Ch. 5.5 - Prob. 99PCh. 5.5 - A 4-m 5-m 6-m room is to be heated by an...Ch. 5.5 - A house has an electric heating system that...Ch. 5.5 - A long roll of 2-m-wide and 0.5-cm-thick 1-Mn...Ch. 5.5 - Prob. 103PCh. 5.5 - Prob. 104PCh. 5.5 - Argon steadily flows into a constant-pressure...Ch. 5.5 - Steam enters a long, horizontal pipe with an inlet...Ch. 5.5 - Refrigerant-134a enters the condenser of a...Ch. 5.5 - A hair dryer is basically a duct in which a few...Ch. 5.5 - A hair dryer is basically a duct in which a few...Ch. 5.5 - Air enters the duct of an air-conditioning system...Ch. 5.5 - An insulated rigid tank is initially evacuated. A...Ch. 5.5 - A rigid, insulated tank that is initially...Ch. 5.5 - Prob. 115PCh. 5.5 - A 2-m3 rigid tank initially contains air at 100...Ch. 5.5 - A 0.2-m3 rigid tank equipped with a pressure...Ch. 5.5 - Prob. 118PCh. 5.5 - An insulated 40-ft3 rigid tank contains air at 50...Ch. 5.5 - A 4-L pressure cooker has an operating pressure of...Ch. 5.5 - An air-conditioning system is to be filled from a...Ch. 5.5 - Oxygen is supplied to a medical facility from ten...Ch. 5.5 - A 0.05-m3 rigid tank initially contains...Ch. 5.5 - A 0.12-m3 rigid tank contains saturated...Ch. 5.5 - A 0.3-m3 rigid tank is filled with saturated...Ch. 5.5 - The air-release flap on a hot-air balloon is used...Ch. 5.5 - Prob. 127PCh. 5.5 - An insulated 0.15-m3 tank contains helium at 3 MPa...Ch. 5.5 - A vertical pistoncylinder device initially...Ch. 5.5 - A vertical piston-cylinder device initially...Ch. 5.5 - A pistoncylinder device initially contains 0.6 kg...Ch. 5.5 - The weighted piston of the device shown in Fig....Ch. 5.5 - Prob. 136RPCh. 5.5 - Prob. 137RPCh. 5.5 - Prob. 138RPCh. 5.5 - Air at 4.18 kg/m3 enters a nozzle that has an...Ch. 5.5 - Prob. 140RPCh. 5.5 - An air compressor compresses 15 L/s of air at 120...Ch. 5.5 - A steam turbine operates with 1.6 MPa and 350C...Ch. 5.5 - Refrigerant-134a enters an adiabatic compressor at...Ch. 5.5 - Prob. 144RPCh. 5.5 - Prob. 145RPCh. 5.5 - Prob. 146RPCh. 5.5 - Prob. 147RPCh. 5.5 - Steam enters a nozzle with a low velocity at 150C...Ch. 5.5 - Prob. 149RPCh. 5.5 - Prob. 150RPCh. 5.5 - Prob. 151RPCh. 5.5 - Prob. 152RPCh. 5.5 - Prob. 153RPCh. 5.5 - Cold water enters a steam generator at 20C and...Ch. 5.5 - An ideal gas expands in an adiabatic turbine from...Ch. 5.5 - Determine the power input for a compressor that...Ch. 5.5 - Prob. 157RPCh. 5.5 - Prob. 158RPCh. 5.5 - Prob. 159RPCh. 5.5 - Prob. 160RPCh. 5.5 - In a dairy plant, milk at 4C is pasteurized...Ch. 5.5 - Prob. 162RPCh. 5.5 - Prob. 163RPCh. 5.5 - Prob. 164RPCh. 5.5 - Prob. 165RPCh. 5.5 - Prob. 166RPCh. 5.5 - The average atmospheric pressure in Spokane,...Ch. 5.5 - The ventilating fan of the bathroom of a building...Ch. 5.5 - Prob. 169RPCh. 5.5 - Determine the rate of sensible heat loss from a...Ch. 5.5 - Prob. 171RPCh. 5.5 - An air-conditioning system requires airflow at the...Ch. 5.5 - A building with an internal volume of 400 m3 is to...Ch. 5.5 - The maximum flow rate of standard shower heads is...Ch. 5.5 - Prob. 176RPCh. 5.5 - Prob. 177RPCh. 5.5 - Steam enters a turbine steadily at 7 MPa and 600C...Ch. 5.5 - Reconsider Prob. 5178. Using appropriate software,...Ch. 5.5 - Prob. 180RPCh. 5.5 - A liquid R-134a bottle has an internal volume of...Ch. 5.5 - A pistoncylinder device initially contains 2 kg of...Ch. 5.5 - A pistoncylinder device initially contains 1.2 kg...Ch. 5.5 - A pressure cooker is a pot that cooks food much...Ch. 5.5 - A tank with an internal volume of 1 m3 contains...Ch. 5.5 - In a single-flash geothermal power plant,...Ch. 5.5 - An adiabatic air compressor is to be powered by a...Ch. 5.5 - The turbocharger of an internal combustion engine...Ch. 5.5 - Prob. 189RPCh. 5.5 - Consider an evacuated rigid bottle of volume V...Ch. 5.5 - An adiabatic heat exchanger is used to heat cold...Ch. 5.5 - A heat exchanger is used to heat cold water at 15C...Ch. 5.5 - An adiabatic heat exchanger is used to heat cold...Ch. 5.5 - In a shower, cold water at 10C flowing at a rate...Ch. 5.5 - Prob. 195FEPCh. 5.5 - Prob. 196FEPCh. 5.5 - Hot combustion gases (assumed to have the...Ch. 5.5 - Steam expands in a turbine from 4 MPa and 500C to...Ch. 5.5 - Steam is compressed by an adiabatic compressor...Ch. 5.5 - Refrigerant-134a is compressed by a compressor...Ch. 5.5 - Refrigerant-134a at 1.4 MPa and 70C is throttled...Ch. 5.5 - Prob. 202FEPCh. 5.5 - Prob. 203FEPCh. 5.5 - Air at 27C and 5 atm is throttled by a valve to 1...Ch. 5.5 - Steam at 1 MPa and 300C is throttled adiabatically...Ch. 5.5 - Air is to be heated steadily by an 8-kW electric...Ch. 5.5 - Saturated water vapor at 40C is to be condensed as...
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
- 1) refrigerated space at -35°C by rejecting waste heat to cooling water that enters the condenser at T, C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser a leaves at the same pressure subcooled by T, C. If the compressor consumes 3.3 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load, Q. (c) the COP. Is this cycle reversible or irreversible? Explain. A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the 1.2 MPa and 50°C and Notes: If the last digit of your student number is less than 5,1 T, is equal to the last digit of your student number. T. 16°C. It is 20°C otherwise. in any ofogse questions, yoearrow_forwardRefrigerant-134a at a rate of 0.08 kg/s enters the compressor of a refrigerator as superheated vapor at 0.18 MPa and 0 ℃ and leaves at 0.9 MPa and 80 ℃. The refrigerant is cooled in the condenser to 31.3 ℃ and 0.8 MPa and it is throttled to 0.18 MPa. Disregarding any heat transfer and pressure drops in the connecting lines between the components, a) Show the cycle on a T-S diagram b) Determine the rate of heat removal from the refrigerated space and the power input to the compressor c) Determine the adiabatic efficiency of the compressor d) Determine the coefficient of performance of the refrigerator.arrow_forwardIn a closed feedwater heater, steam warms the feedwater and the condensate leaves the heater through a trap or throttling value . What is the purpose of the trap or throttling value? It allows the liquid to flow to higher pressures with the same internal energy. It separates the liquid from the vapor. It allows the liquid to flow into a lower pressures without the loss of enthalpy. It allows the liquid to flow to higher pressures with the same enthalpy. It allows the liquid to flow into a lower pressures without the loss of internal energy.arrow_forward
- Heat is rejected from the condenser of a heat pump cycle by refrigerant-134a entering at 700 kPa and 50 ◦C at a rate of 105 kg/h and leaves as a saturated liquid. Determine (a) the temperature of R-134a at the condenser exit, (b) the volume flow rate at the exit of the condenser in L/min, (c) the COP of the heat pump if the rate of heat absorbed in the evaporator is 12,000 Btu/h.arrow_forwardA vacuum refrigeration system consists of a large insulated flash chamber kept at low pressure by steam ejector which pumps vapor to a condenser. Condensate is removed by condensate to an air vent. Warm return water enters the flash chamber at 13oC, chilled water comes out of the flash chamber at 5oC Vapor leaving the flash chamber has a quality of 0.97 and the temperature in the condenser is 32oC. For 350 kw of refrigeration A) How much chilled water at 5oC does this system provide? B) How much make-up water is needed? C) How much vapor must the steam ejector remove from the flash chamber?arrow_forwardA vacuum refrigeration system consists of a large insulated flash chamber kept at low pressure by steam ejector which pumps vapor to a condenser. Condensate is removed by condensate to an air vent. Warm return water enters the flash chamber at 13oC, chilled water comes out of the flash chamber at 5oC Vapor leaving the flash chamber has a quality of 0.97 and the temperature in the condenser is 32oC. For 350 kw of refrigeration How much make-up water is needed?arrow_forward
- A vacuum refrigeration system consists of a large insulated flash chamber kept at low pressure by steam ejector which pumps vapor to a condenser. Condensate is removed by condensate to an air vent. Warm return water enters the flash chamber at 13oC, chilled water comes out of the flash chamber at 5oC Vapor leaving the flash chamber has a quality of 0.97 and the temperature in the condenser is 32oC. For 350 kw of refrigeration How much vapor must the steam ejector remove from the flash chamber?arrow_forwardNeed solution to question 6 only within 20 minutes (answer of question 5 is 6.82m/s)arrow_forwardRefrigerant 134a enters a refrigerator compressor as superheated vapor at 0.20 MPa and -5 ° C at a rate of 0.7 kg / s, and exits at 1.2 MPa and 70 ° C. The refrigerant is cooled in the condenser to 44 ° C and 1.15 MPa, and is throttled to 0.2 MPa. Neglecting any heat transfer and any pressure drop in the connecting lines between the components, show the cycle on a Ts and Ph diagram with respect to the saturation lines, and 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 COP of the refrigeratorarrow_forward
- Steam with quality 0.85 enters the condenser of a power plant at 20 kPa with a mass flow rate 10 kg/s. It is cooled by water from a nearby river by circulating through the tubes inside the condenser. If the steam leaves the condenser as saturated liquid at 20 kPa and the temperature rise of the cooling water is 15°C, (a) determine the minimum mass flow rate of the cooling water required, (b) determine the heat transfer rate from the steam to the cooling water. Hint: Average specific heats at room temperature can be used for the cooling water from river. E Waterarrow_forward1) Air enters an adiabatic heat exchanger (HX) with a mass flow rate of 850 kg/s at T₁ = 350°C and P₁ = 110kPa and leaves at T₂ = 60°C and P₂ = 100kPa and transfers heat to water which enters the HX as a saturated liquid at 16MPa. The water mass flow rate is 160 kg/s and it leaves the HX at 15MPa. Air has a constant specific heat of Cp = 1.013 kJ/kg . K and specific heat ratio of k = 1.395. Calculate b) the exergy destruction rate of the HX, in MW if the dead state temperature is T₂ = 20°C. To Hot stream + w ww 3 84 Cold streamarrow_forward1) Air enters an adiabatic heat exchanger (HX) with a mass flow rate of 850 kg/s at T₁ = 350°C and P₁ = 110kPa and leaves at T₂ = 60°C and P₂ = 100kPa and transfers heat to water which enters the HX as a saturated liquid at 16MPa. The water mass flow rate is 160 kg/s and it leaves the HX at 15MPa. Air has a constant specific heat of cp = 1.013 kJ/kg . K and specific heat ratio of k = 1.395. Calculate a) the temperature of water at state 4 Hot+ stream + To www ww 3 4 Cold streamarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
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