Thermodynamics: An Engineering Approach ( 9th International Edition ) ISBN:9781260092684
9th Edition
ISBN: 9781260048667
Author: Yunus A. Cengel Dr.; Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 10.9, Problem 44P
To determine
How to justify the following action:
During a regeneration process, some steam is extracted from the turbine and is used to heat the liquid water leaving the pump. This does not seem like a smart thing to do since the extracted steam could produce some more work in the turbine.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A steam power plant operates on the cycle shown in Fig. 10-5. If the isen-
tropic efficiency of the turbine is 87 percent and the isentropic efficiency of
the pump is 85 percent, determine (a) the thermal efficiency of the cycle
and (bi the net power output of the plant for a mass flow rate of 15 kg's.
15.9 MPa
15.2 MPa
35°C
625 C
Boiler
1S MPa
600 C
O 16 MPa
Wihat
Turbine
= 087
Pump
Of 10 kPa
9 AP
38°C
Condenser
A steam power plant operates on the cycle shown in Fig. 10-5. If the isen-
tropic efficiency of the turbine is 87 percent and the isentropic efficiency of
the pump is 85 percent, determine (a) the thermal efficiency of the cycle
and (b) the net power output of the plant for a mass flow rate of 15 kg's.
15.9 MPa
35 C
15.2 MPa
625 C
Beiler
15 MPa
16 MPa
Turbine
y= 087
Pump
t0 kPa
9 APa
38C
Condenser
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 MPaThe 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
Chapter 10 Solutions
Thermodynamics: An Engineering Approach ( 9th International Edition ) ISBN:9781260092684
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
- A power plant uses a gas turbine to produce electricity. Assume that the gas-turbine operates on the ideal Brayton cycle has a pressure ratio of 8. The outside air temperature is 27 °C and without preheating, the air is drawn into the compressor. The air compressed in the compressor and its pressure and temperature increase. Thereafter it is supplied into the combustion chamber where its temperature increases to 1023 °C at constant pressure. Thereafter, hot air is drawn into the turbine. By considering the air-standard assumptions, determine (a) the gas temperature at the exits of the compressor and the turbine (b) the back work ratio (c) the thermal efficiencyarrow_forwardA power plant uses a gas turbine to produce electricity. Assume that the gas-turbine operates on the ideal Brayton cycle has a pressure ratio of 8. The outside air temperature is 27 C and without preheating, the air is drawn into the compressor. The air compressed in the compressor and its pressure and temperature increase. Thereafter it is supplied into the combustion chamber where its temperature increases to 1023 C at constant pressure. Thereafter, hot air is drawn into the turbine. By considering the air-standard assumptions, determine (a) the gas temperature at the exits of the compressor and the turbine (b) the back work ratio (c) the thermal efficiencyarrow_forwardAt a given compression ratio, which cycle has a higher thermal efficiency?arrow_forward
- (7). In a gas turbine system air is taken into the compressor at 100kPa and 18°C. It is compressed through a compression ratio of 5:1 with an isentropic efficiency of 85%. The air passes to a combustion chamber where it is heated to 815°C by the addition of fuel. In the turbine it is expanded down to 100kPa with an isentropic efficiency of 88%. If the mass flowrate of the air is 4.5kg/s and the mass of fuel neglected, calculate: (a). the net power output of the turbine if it is coupled to the compressor (b). the plant's thermal efficiency (c). the mass of fuel burnt per hour (d). the air-fuel ratio The calorific value of the fuel is 43.3MJ/kgarrow_forwardCooler 2 currently operates using R-134a as a refrigerant. The 2nd stage of your project is to study the possibility of exchanging this working fluid for ammonia (R-717), which is less harmful to the environment. To make this choice, you must evaluate the performance of Cooler 2 by calculating the coefficient of cycle performance (COP) for each fluid. Chiller 2 also operates at a flow rate of 1.4 kg/s, whose evaporation and condensing temperatures are -10 °C and 30 °C. The evaporation (1 → 2) and condensation (3 → 4) steps operate at constant pressures, so the pressure of each of these two steps is the saturation pressure relative to the operating temperature. For this 2nd step, you must deliver the project report with the following information: 2.a. Cycle COP using R-134a as refrigerant; 2.b. Cycle COP using R-717 as refrigerant; 2.c. Your opinion as an engineer on which of the two working fluids has a better performance, exclusively analyzing the cycle performance coefficients…arrow_forwardMuhammad is a Mechanical Engineering major at UCR, and his team just got their butts kicked by an ME team from CSUN in a design competition. The CSUN team had a great power cycle, and one of their members (Arman) was laughing at them the entire time. When Muhammad returns to UCR he goes straight to the lab and begins working on a better power cycle design. Muhammad's power cycle takes air that is initially at a pressure of 240 kPa and a volume of 4 m³. In the first step, the air undergoes isothermal expansion to a volume of 12 m. In the second step, the air undergoes isobaric expansion to a volume of 20 m². In the third step, the air undergoes isochoric pressurization back to 240 kPa. In the fourth, and final, step the air undergoes isobaric contraction to a volume of 4 m³. What is the net heat flow, per cycle, in Muhammad’s power cycle? [Hint: Draw a PV diagram of the process. It will help.]arrow_forward
- A steam turbine cycle running on a Rankin cycle between the condenser pressure of 10 kPa and the boiler pressure of 165 bar, the steam enters the high pressure turbine at a temperature of 600 ° C. The average turbine expands to 800 kPa and then enters the boiler again to be reheated to 550 ° C. The steam leaves the boiler to a low pressure turbine, where it expands to the condenser pressure. If the expansion and compression in the turbine and the pump is isotropic, and the addition of heat is constant pressure, find the efficiency of the cycle. Note point # 1 at the exit area of the steam from the boilerarrow_forwardThe pressure of the steam going into the turbine of the power plant is 4 MPa and the temperature is 600 degrees celsius. In the turbine, reheating is done at a pressure of 400 kPa, which raises the temperature to 400 degrees. The condensing pressure is 10 kPa. Determine the power of the turbine if the mass flow is 12 kg/s. What is the efficiency of the cycle? How to draw the cycle to Ts-diagram?arrow_forwardSuperheated water vapor enters the turbine at 5Mpa and 4000C. The water leaves the condenser as saturated liquid at a pressure of 30kPa, and the turbine efficiency is 91%. The net power output of the cycle is 100MW. Determine the thermal efficiency.arrow_forward
- combined heat rate, and the total throttle flow for the rated power. (5)A steam power plant operates on the cycle shown in the figure. If the isentropic efficiency of the turbine is 87 percent and the isentropic efficiency of the pump is 85 percent, determine (a) the thermal efficiency of the cycle and (b) the net power output of the plant for a mass flow rate of 15 kg/s. 152 MP 625'C 15.9 MPa 35°C Boilerarrow_forwardWhich is more efficient reheat regenerative cycle or the regenerative cycle? Why?arrow_forwardA steam turbine cycle running on a Rankin cycle between a condenser pressure of 10 kPa and a boiler pressure of 20 MPa, the steam enters the high pressure turbine at a temperature of 600 ° C. The average turbine expands to 800 kPa and then enters the boiler again to be reheated to 500 ° C. The steam leaves the boiler to a low pressure turbine, where it expands to the condenser pressure. If the expansion and compression in the turbine and the pump is isotropic, and the addition of heat is constant pressure, find the efficiency of the cycle. Note point # 1 at the vapor exit region of the condenserarrow_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