Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781260048766
Author: CENGEL
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Videos
Question
Chapter 8.8, Problem 78P
To determine
The amount of exergy destroyed by the family per year.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Refrigerant-22 absorbs heat from a cooled space at 50°F as it flows through an evaporator of a refrigeration system. R-22 enters the evaporator at 10°F at a rate of 0.08 lbm/s with a quality of 0.3 and leaves as a saturated vapor at the same pressure. Determine the rate of exergy destruction in the evaporato.
3) The cold water system in a house is equipped with a pump. 12 kg of water at 5000kPa and
2°C will enter the pump until the pressure rises 3 times and the temperature is 12°C with 3kJ
of heat loss. Hot water will be heated in a heat exchanger before entering the mixing
chamber. The heat exchanger uses air at 150°C to heat 3kg of 5°C of 5MPA water until
120°C. The temperature of the air will be dropped 10 times than before. Later, the cold water
will enter the mixing chamber to be mixed with hot water until the pressure of the water
becomes 10MPA. Evaluate :
a) work of the pump
b) isentropic efficiency of the pump
c) mass of the air used to heat the water
d) heat add in the hot water
e) temperature of the water at the exit of the mixing chamber in °C.
In a refrigerant-cooling system, 1.5 kg/s of refrigerant 134a flows at steady state through a coil having an inside diameter of 0.05 m. The refrigerant enters the tube as superheated vapor at 700 kPa and 70°C and leaves at 32°C and 690 kPa. You want to heat the water from of 25°C to 35°C by placing the coil inside a box and having the water enter and leave the box at a constant mass flow rate. Please answer the following: Please answer the following. a. Create a schematic that accurately describes the situation given in the problem. Include your chosen boundary and the energy interactions present across the boundary. You will select from which side the cold water enters the box; that is, closer to the inlet of the refrigerant at 70°C or closer to the exit of the refrigerant at 32°C. b. Represent the process for the refrigerant on a T-v diagram. Show the isobars corresponding to each state with their value. Include values on the axes using customary units. c. For this part you are going…
Chapter 8 Solutions
Thermodynamics: An Engineering Approach
Ch. 8.8 - What final state will maximize the work output of...Ch. 8.8 - Is the exergy of a system different in different...Ch. 8.8 - Under what conditions does the reversible work...Ch. 8.8 - How does useful work differ from actual work? For...Ch. 8.8 - How does reversible work differ from useful work?Ch. 8.8 - Is a process during which no entropy is generated...Ch. 8.8 - Consider an environment of zero absolute pressure...Ch. 8.8 - It is well known that the actual work between the...Ch. 8.8 - Consider two geothermal wells whose energy...Ch. 8.8 - Consider two systems that are at the same pressure...
Ch. 8.8 - Prob. 11PCh. 8.8 - Does a power plant that has a higher thermal...Ch. 8.8 - Prob. 13PCh. 8.8 - Saturated steam is generated in a boiler by...Ch. 8.8 - One method of meeting the extra electric power...Ch. 8.8 - A heat engine that receives heat from a furnace at...Ch. 8.8 - Consider a thermal energy reservoir at 1500 K that...Ch. 8.8 - A heat engine receives heat from a source at 1100...Ch. 8.8 - A heat engine that rejects waste heat to a sink at...Ch. 8.8 - A geothermal power plant uses geothermal liquid...Ch. 8.8 - A house that is losing heat at a rate of 35,000...Ch. 8.8 - A freezer is maintained at 20F by removing heat...Ch. 8.8 - Prob. 24PCh. 8.8 - Prob. 25PCh. 8.8 - Prob. 26PCh. 8.8 - Can a system have a higher second-law efficiency...Ch. 8.8 - A mass of 8 kg of helium undergoes a process from...Ch. 8.8 - Which is a more valuable resource for work...Ch. 8.8 - Which has the capability to produce the most work...Ch. 8.8 - The radiator of a steam heating system has a...Ch. 8.8 - A well-insulated rigid tank contains 6 lbm of a...Ch. 8.8 - A pistoncylinder device contains 8 kg of...Ch. 8.8 - Prob. 35PCh. 8.8 - Prob. 36PCh. 8.8 - Prob. 37PCh. 8.8 - A pistoncylinder device initially contains 2 L of...Ch. 8.8 - A 0.8-m3 insulated rigid tank contains 1.54 kg of...Ch. 8.8 - An insulated pistoncylinder device initially...Ch. 8.8 - Prob. 41PCh. 8.8 - An insulated rigid tank is divided into two equal...Ch. 8.8 - A 50-kg iron block and a 20-kg copper block, both...Ch. 8.8 - Prob. 45PCh. 8.8 - Prob. 46PCh. 8.8 - Prob. 47PCh. 8.8 - A pistoncylinder device initially contains 1.4 kg...Ch. 8.8 - Prob. 49PCh. 8.8 - Prob. 50PCh. 8.8 - Prob. 51PCh. 8.8 - Air enters a nozzle steadily at 200 kPa and 65C...Ch. 8.8 - Prob. 54PCh. 8.8 - Prob. 55PCh. 8.8 - Argon gas enters an adiabatic compressor at 120...Ch. 8.8 - Prob. 57PCh. 8.8 - Prob. 58PCh. 8.8 - The adiabatic compressor of a refrigeration system...Ch. 8.8 - Refrigerant-134a at 140 kPa and 10C is compressed...Ch. 8.8 - Air enters a compressor at ambient conditions of...Ch. 8.8 - Combustion gases enter a gas turbine at 900C, 800...Ch. 8.8 - Steam enters a turbine at 9 MPa, 600C, and 60 m/s...Ch. 8.8 - Refrigerant-134a is condensed in a refrigeration...Ch. 8.8 - Prob. 66PCh. 8.8 - Refrigerant-22 absorbs heat from a cooled space at...Ch. 8.8 - Prob. 68PCh. 8.8 - Prob. 69PCh. 8.8 - Air enters a compressor at ambient conditions of...Ch. 8.8 - Hot combustion gases enter the nozzle of a...Ch. 8.8 - Prob. 72PCh. 8.8 - A 0.6-m3 rigid tank is filled with saturated...Ch. 8.8 - Prob. 74PCh. 8.8 - Prob. 75PCh. 8.8 - An insulated vertical pistoncylinder device...Ch. 8.8 - Liquid water at 200 kPa and 15C is heated in a...Ch. 8.8 - Prob. 78PCh. 8.8 - Prob. 79PCh. 8.8 - A well-insulated shell-and-tube heat exchanger is...Ch. 8.8 - Steam is to be condensed on the shell side of a...Ch. 8.8 - Prob. 82PCh. 8.8 - Prob. 83PCh. 8.8 - Prob. 84PCh. 8.8 - Prob. 85RPCh. 8.8 - Prob. 86RPCh. 8.8 - An aluminum pan has a flat bottom whose diameter...Ch. 8.8 - Prob. 88RPCh. 8.8 - Prob. 89RPCh. 8.8 - A well-insulated, thin-walled, counterflow heat...Ch. 8.8 - Prob. 92RPCh. 8.8 - Prob. 93RPCh. 8.8 - Prob. 94RPCh. 8.8 - Prob. 95RPCh. 8.8 - Nitrogen gas enters a diffuser at 100 kPa and 110C...Ch. 8.8 - Prob. 97RPCh. 8.8 - Steam enters an adiabatic nozzle at 3.5 MPa and...Ch. 8.8 - Prob. 99RPCh. 8.8 - A pistoncylinder device initially contains 8 ft3...Ch. 8.8 - An adiabatic turbine operates with air entering at...Ch. 8.8 - Steam at 7 MPa and 400C enters a two-stage...Ch. 8.8 - Prob. 103RPCh. 8.8 - Steam enters a two-stage adiabatic turbine at 8...Ch. 8.8 - Prob. 105RPCh. 8.8 - Prob. 106RPCh. 8.8 - Prob. 107RPCh. 8.8 - Prob. 108RPCh. 8.8 - Prob. 109RPCh. 8.8 - Prob. 111RPCh. 8.8 - A passive solar house that was losing heat to the...Ch. 8.8 - Prob. 113RPCh. 8.8 - A 4-L pressure cooker has an operating pressure of...Ch. 8.8 - Repeat Prob. 8114 if heat were supplied to the...Ch. 8.8 - Prob. 116RPCh. 8.8 - A rigid 50-L nitrogen cylinder is equipped with a...Ch. 8.8 - Prob. 118RPCh. 8.8 - Prob. 119RPCh. 8.8 - Prob. 120RPCh. 8.8 - Reconsider Prob. 8-120. The air stored in the tank...Ch. 8.8 - Prob. 122RPCh. 8.8 - Prob. 123RPCh. 8.8 - Prob. 124RPCh. 8.8 - Prob. 125RPCh. 8.8 - Prob. 126RPCh. 8.8 - Prob. 127RPCh. 8.8 - Water enters a pump at 100 kPa and 30C at a rate...Ch. 8.8 - Prob. 129RPCh. 8.8 - Prob. 130RPCh. 8.8 - Obtain a relation for the second-law efficiency of...Ch. 8.8 - Writing the first- and second-law relations and...Ch. 8.8 - Prob. 133RPCh. 8.8 - Keeping the limitations imposed by the second law...Ch. 8.8 - Prob. 135FEPCh. 8.8 - Prob. 136FEPCh. 8.8 - Prob. 137FEPCh. 8.8 - Prob. 138FEPCh. 8.8 - A furnace can supply heat steadily at 1300 K at a...Ch. 8.8 - A heat engine receives heat from a source at 1500...Ch. 8.8 - Air is throttled from 50C and 800 kPa to a...Ch. 8.8 - Prob. 142FEPCh. 8.8 - A 12-kg solid whose specific heat is 2.8 kJ/kgC is...
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
- I got previous help from a Bartleby expert but unfortunately their answer was incorrect.arrow_forwardA piston–cylinder device contains 8 kg of refrigerant- 134a at 0.7 MPa and 60°C. The refrigerantis now cooled at constant pressure until it exists as a liquid at 20°C. If the surroundings areat 100 kPa and 20°C, determine,a) the exergy of the refrigerant at the initial and the final states,b) the exergy destroyed during this process.arrow_forwardWater enter a pump at environmental conditions, 100 kPa and 20°C at a rate of 1.5 kg/s and leave at 5 MPa. The pump has an isentropic effficiency of 80 percent, determine (a) Show the system sketch(b) the actual power input(c) the exergy destructionarrow_forward
- Devices can be combined to perform a variety of tasks. An adiabatic compressor, with air as the working fluid, is to be powered by an adiabatic steam turbine, which is also driving a generator. Steam enters the turbine at 12.5 MPa and 500 ∘C500 ∘C at a steady rate of 27.30 kg/s27.30 kg/s and exits at 10 kPa and a quality of 0.8710.0.8710. Air enters the compressor at 98 kPa and 295.0 K295.0 K at a steady rate of 12.600 kg/s12.600 kg/s and exits at 1 MPa and 635.0 K.635.0 K. For air, MW=29.0 g/mol,MW=29.0 g/mol, ??=3.5R.Cp=3.5R. Note: The IUPAC sign convention for work is used. Work into the system has a positive value. What is the magnitude of the power delivered to the generator by the turbine?arrow_forwardRefrigerant-134a is condensed in a refrigeration system by rejecting heat to ambient air at 25°C. R-134a enters the condenser at 700 kPa and 50°C at a rate of 0.05 kg/s and leaves at the same pressure as a saturated liquid. Determine the rate of exergy destruction in the condenser.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
- One can store energy by compressing air and use it later to power a turbine to create energywhen needed. The air must be heated to make this effective, which can be accomplished by compressing the air under adiabatic conditions. This is called adiabatic compressed air energy storage (CAES). Inside a typical power plant, 5.8×10^6 kg of N2 gas is at 25 °C is compressed from atmospheric to pressure into a volume of 300,000 m3 (they use abandoned salt mines). The process is done reversibly and adiabatically. What is q, n, Vi, Pf, T, U,w, and H and for this process? (Cp,m = 29.12 J/K/mol and Cv,m = 20.80 J/K/mol for N2). Assume perfect gas behavior.arrow_forwardA Carnot’s engine is operated between two reservoirs at temperature 450 K and 350 K. If the engine receives 1000 calories of heat from the source in each cycle, calculate the amount of heat rejected to the sink in each cycle. Calculate the efficiency of the engine and the work done by the engine in each cycle.arrow_forwardRate of exergy destroyarrow_forward
- A heat pump with refrigerant-134a as the working fluid is used to keep a space at 25 C by absorbing heat from geothermal water that enters the evaporator at 60 C at a rate of 0.065 kg/s and leaves at 40 C. Refrigerant enters the evaporator at 12 C with a quality of 15 percent and leaves at the same pressure as saturated vapor. If the compressor consumes 1.6 kW of power, determine; (a) the mass flow rate of the refrigerant, (b) the rate of heat supply, (c) the COP, and (d) the minimum power input to the compressor for the same rate of heat supply.arrow_forward4. 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 requiredarrow_forwardA 4-L pressure cooker has an operating pressure of 175 kPa. Initially, one-half of the volume is filled with liquid water and the other half by water vapor. The cooker is now placed on top of a 750-W electrical heating unit that is kept on for 20 min. Assuming the surroundings to be at 25°C and 100 kPa, determine the exergy destruction associated with the entire process.arrow_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 Press
Mechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSON
Thermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEY
Mechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage Learning
Engineering 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
Thermodynamic Availability, What is?; Author: MechanicaLEi;https://www.youtube.com/watch?v=-04oxjgS99w;License: Standard Youtube License