Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781260048766
Author: CENGEL
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 10.9, Problem 132FEP
Consider a combined gas-steam power plant. Water for the steam cycle is heated in a well-insulated heat exchanger by the exhaust gases that enter at 800 K at a rate of 60 kg/s and leave at 400 K. Water enters the heat exchanger at 200°C and 8 MPa and leaves at 350°C and 8 MPa. If the exhaust gases are treated as air with constant specific heats at room temperature, the mass flow rate of water through the heat exchanger becomes
- (a) 11 kg/s
- (b) 24 kg/s
- (c) 46 kg/s
- (d) 53 kg/s
- (e) 60 kg/s
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Steam enters the turbine of a cogeneration plant at 6 MPa and 550 degrees C . One-third of the steam is extracted from the turbine at 1400 kPa pressure for process heating. The remaining steam continues to expand to 20 kPa. The extracted steam is then condensed and mixed with feedwater at constant pressure and the mixture is pumped to the boiler pressure of 6 MPa The mass flow rate of steam through the boiler is 30 kg/s. Disregarding any pressure drops and heat losses in the piping, and assuming the turbine and the pump to be isentropic, determine (a) the net power produced(b) the utilization factor of the plant, (c) the exergy destruction associated with the process heating, and (d ) the entropy generation associated with the process in the boiler. Assuming a source temperature of 1000 K and a sink temperature of 298 K
A gas turbine draws in air at 98kPa....
In a power plant steam, steam is continuously extracted
from the turbine and in a heat exchanger there is a condensation of the extracted steam. The energy released during condensation of steam is used to operate a heat engine. A heat engine receives thermal energy at a rate of 1200 kJ/min from condensing steam and rejects waste heat to a lake at 25°C at a rate of 850 kJ/min. Determine the lowest possible condensing steam temperature.
Chapter 10 Solutions
Thermodynamics: An Engineering Approach
Ch. 10.9 - Why is the Carnot cycle not a realistic model for...Ch. 10.9 - Why is excessive moisture in steam undesirable in...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - A steady-flow Carnot cycle uses water as the...Ch. 10.9 - Consider a steady-flow Carnot cycle with water as...Ch. 10.9 - Water enters the boiler of a steady-flow Carnot...Ch. 10.9 - What four processes make up the simple ideal...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...
Ch. 10.9 - How do actual vapor power cycles differ from...Ch. 10.9 - Compare the pressures at the inlet and the exit of...Ch. 10.9 - The entropy of steam increases in actual steam...Ch. 10.9 - Is it possible to maintain a pressure of 10 kPa in...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle which uses water as...Ch. 10.9 - Consider a solar-pond power plant that operates on...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - Consider a 210-MW steam power plant that operates...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A steam Rankine cycle operates between the...Ch. 10.9 - A simple Rankine cycle uses water as the working...Ch. 10.9 - The net work output and the thermal efficiency for...Ch. 10.9 - A binary geothermal power plant uses geothermal...Ch. 10.9 - Consider a coal-fired steam power plant that...Ch. 10.9 - Show the ideal Rankine cycle with three stages of...Ch. 10.9 - Is there an optimal pressure for reheating the...Ch. 10.9 - How do the following quantities change when a...Ch. 10.9 - Consider a simple ideal Rankine cycle and an ideal...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Steam enters the high-pressure turbine of a steam...Ch. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - A steam power plant operates on an ideal reheat...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1041 assuming both the pump and the...Ch. 10.9 - Prob. 43PCh. 10.9 - Prob. 44PCh. 10.9 - How do open feedwater heaters differ from closed...Ch. 10.9 - How do the following quantities change when the...Ch. 10.9 - Cold feedwater enters a 200-kPa open feedwater...Ch. 10.9 - In a regenerative Rankine cycle. the closed...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Consider an ideal steam regenerative Rankine cycle...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - Repeat Prob. 1060, but replace the open feedwater...Ch. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A simple ideal Rankine cycle with water as the...Ch. 10.9 - Prob. 64PCh. 10.9 - An ideal reheat Rankine cycle with water as the...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Prob. 67PCh. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - The schematic of a single-flash geothermal power...Ch. 10.9 - What is the difference between cogeneration and...Ch. 10.9 - Prob. 71PCh. 10.9 - Prob. 72PCh. 10.9 - Consider a cogeneration plant for which the...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - A large food-processing plant requires 1.5 lbm/s...Ch. 10.9 - An ideal cogeneration steam plant is to generate...Ch. 10.9 - Steam is generated in the boiler of a cogeneration...Ch. 10.9 - Consider a cogeneration power plant modified with...Ch. 10.9 - Prob. 80PCh. 10.9 - Why is the combined gassteam cycle more efficient...Ch. 10.9 - The gas-turbine portion of a combined gassteam...Ch. 10.9 - A combined gassteam power cycle uses a simple gas...Ch. 10.9 - Reconsider Prob. 1083. An ideal regenerator is...Ch. 10.9 - Reconsider Prob. 1083. Determine which components...Ch. 10.9 - Consider a combined gassteam power plant that has...Ch. 10.9 - Prob. 89PCh. 10.9 - What is the difference between the binary vapor...Ch. 10.9 - Why is mercury a suitable working fluid for the...Ch. 10.9 - Why is steam not an ideal working fluid for vapor...Ch. 10.9 - By writing an energy balance on the heat exchanger...Ch. 10.9 - Prob. 94RPCh. 10.9 - Steam enters the turbine of a steam power plant...Ch. 10.9 - Consider a steam power plant operating on the...Ch. 10.9 - A steam power plant operates on an ideal Rankine...Ch. 10.9 - Consider a steam power plant that operates on a...Ch. 10.9 - Repeat Prob. 1098 assuming both the pump and the...Ch. 10.9 - Consider an ideal reheatregenerative Rankine cycle...Ch. 10.9 - Prob. 101RPCh. 10.9 - A textile plant requires 4 kg/s of saturated steam...Ch. 10.9 - Consider a cogeneration power plant that is...Ch. 10.9 - Prob. 104RPCh. 10.9 - Prob. 105RPCh. 10.9 - Reconsider Prob. 10105E. It has been suggested...Ch. 10.9 - Reconsider Prob. 10106E. During winter, the system...Ch. 10.9 - Prob. 108RPCh. 10.9 - Prob. 109RPCh. 10.9 - A steam power plant operates on an ideal...Ch. 10.9 - A Rankine steam cycle modified for reheat, a...Ch. 10.9 - Show that the thermal efficiency of a combined...Ch. 10.9 - Prob. 118RPCh. 10.9 - A solar collector system delivers heat to a power...Ch. 10.9 - Starting with Eq. 1020, show that the exergy...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle. If the...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a simple ideal Rankine cycle with fixed...Ch. 10.9 - Consider a steady-flow Carnot cycle with water as...Ch. 10.9 - Prob. 126FEPCh. 10.9 - Prob. 127FEPCh. 10.9 - A simple ideal Rankine cycle operates between the...Ch. 10.9 - Pressurized feedwater in a steam power plant is to...Ch. 10.9 - Consider a steam power plant that operates on the...Ch. 10.9 - Consider a combined gas-steam power plant. Water...
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
- 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 10°C. If the steam is to leave the condenser as saturated liquid at 20000 Pa, determine the mass flow rate of the cooling water required.arrow_forwardA steady-state gas turbine is using air as the working fluid has shaft power output of 55 MW. Air enters the turbine at 300 K and leaves at 600 K and 30 m/s. The air is first compressed by adding a compression power of 15 MW. Then air receives 173 MW as heat input from the combustor. Determine the mass flow rate of air in kg/s.arrow_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_forward
- 1) 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_forwardA heat exchanger is to heat water (cp = 4.18 kJ/kg·oC) from 25oC to 60oC at a rate of 0.2 kg/s. The heating is to be accomplished by geothermal water (cp = 4.31 kJ/kg·oC) available at 159oC at a mass flow rate of 0.3 kg/s. Find the exit temperature of geothermal water.arrow_forwarda power plant steam, steam is continuously extractedfromthe turbine and in a heat exchanger there is a condensation of the extracted steam. The energy released during condensation of steam is used to operate a heat engine. A heat engine receives thermal energy at a rate of 1200 kJ/hr from condensing steam and rejects waste heat to a lake at 20°C at a rate of 800 kJ/hr. Determine the lowest possible condensing steam temperature.arrow_forward
- A high pressure steam turbine receives steam from a boiler under unknown conditions. The isentropic efficiency of the turbine is 75% and it produces 1MW. The high pressure turbine outlet steam is at 1.4 MPa under saturated conditions. The high pressure turbine exhaust supplies 1000kg/min for use in a process, in addition to an unknown flow of steam that follows the path, being supplied to a low pressure turbine that produces 820kW when it releases steam at 10kPa and has a isentropic efficiency of 60%. The steam that was used for the process (out of the high pressure turbine) after being used, returns to the cycle taken by the pump, which also takes the outlet of the condenser and does so at 10kPa as saturated liquid. Consider the efficiency of the pump equal to 90%. Determine: A) the mass flow through the boiler B) the pressure and temperature at the outlet of the boiler C) the thermal efficiency of the cyclearrow_forwardSteam 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_forwardRefrigerant 134-a enters the condenser of a residential heat pump at 80O0kPa and 35°C at a rate of 0.018kg/s and leaves at 800kPa as a saturated liquid. (Refer to Figure 4). If the compressor consumes 1.2kW of power, determine: (a) the COP of the heat pump (b) the rate of heat absorption from the outside air. 800 kPa Он Saturated 800 kPa liquid 35°C Condenser ´Expansion valve Win Compressor Evaporator Figure 4arrow_forward
- 1. Consider a two-stage turbine with heat addition between the stages as shown in the figure below. Steam at 8 MPa and 500 °C enters the first stage and exits at 0.8 MPa. Before entering the second stage, steam passes through a heat exchanger and its temperature is increased to 400 °C. The pressure of steam at the exit of the second stage is 10 kPa. Both turbines are adiabatic and have isentropic efficiencies of 0.9. The power output of the second stage turbine is 5 MW. Calculate the power output of the first stage turbine. P= 8 MPa T= 500°C R= 0.8 MPa 5= 400°C Steam Turbine 1 Turbine 2 W,= 5 MW P= 0.8 MPa Heat Exchanger P= 10 kPa ---- ---- ---- Hot Combustion Gasesarrow_forwardA steam at 3 MPa and 5 kg/s is entering into an isentropic steam turbine and leave with 100 kPa and 200°C (see Figure Q1). 7% steam at 500 kPa is diverted to a heat exchanger to preheat the feed water with the second outlet from the turbine. (a) Considering the necessary assumptions determine the power output of the turbine in kW. (b) Discuss the conditions for a turbine to operate in an isentropic condition. Compare intuitively the power output of a real turbine and isentropic turbine. (c) The entropy of an actual turbine process increases as a result of irreversibility. To maintain the entropy of the seam at the exit at lower value, it is recommended to use cold water and circulate in the turbine so that the entropy and enthalpy remain at low value when it leaves the turbine, and hence the work output will increase. How do you evaluate thisrecommendation in improving the efficiency of the turbine?arrow_forwardConsider the conditions of Problem 1, homework 5 (it is repeated below) and that the surroundings are at a temperature of 4 C. Instead of mixing the two fluids together consider the following proposal. Heat is allowed to flow from the 3 Kg mass of water through a Carnot heat engine and is rejected to the cooler mass which acts as the low temperature thermal reservoir. Determine the maximum amount of work that could be performed by the heat engine, the entropy produced, and the exergy destroyed in the 3 Kg mass during this operation. Also, determine the total entropy produced and exergy destroyed in the total system. In this case the temperature and internal energy of the mass of water is changing unlike the infinite heat reservoir case. Since the temperature of both the high temperature and low temperature heat input is changing, the Carnot efficiency is also changing. This problem should be solved using a numerical technique that you write using either excel or Matlab. In…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 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
Power Plant Explained | Working Principles; Author: RealPars;https://www.youtube.com/watch?v=HGVDu1z5YQ8;License: Standard YouTube License, CC-BY