Post on 09-Apr-2018
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Power Generation
Thermal Power Pants and their working CyclesHydal Power Plants, run of river, accumulation type, turbines &
stations
Necular Power Plants, reactors, radiation damages.
Thermo Electric, MHD
PV Generators, working principles, Design Specifications
Fuel Cells, working principles
Wind Power Generation
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Power Generation
Recommended Books
Principles of Energy Conversion by Arche W. Culp, Latest Edition
Power Plant Technology by M.M Wakel, Latest Edition
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Power Generation
Quizzes 5
Assignments/ Reports 5
Lab Work/ Experiments
Every student have to pick a topic (Given) and write up a 4-5 pages
comprehensive report at the end of semester+ Presentation of 5-6
Slides.
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Power Generation Thermodynamics
Energy & Life
All Living on Planet Earth Needs Energy.
Food, Sun Radiations,
Modern civilization can only thrive if existing sources
can meet the rising change.
Energy exist in many forms from Atoms of matters to
Radiations of Sun.
Many Sources of Energy known Un known,Transform of Energy fro One form to Other
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Power Generation Thermodynamics
Energy
Chemical Energy of Combustion ofFossil Fuels (Oil, Gas, Coal)
Waste (Agriculture, Domestic, Commercial)
Used to produce heat which in turns produce Mechanical Energy in
Turbines or Pumps.Advantages & Disadvantage
Potential Energy of Water is converted into Mechanical Energy on
Run ofRiver or Storage Dams.
Uranium Atoms are bombarded asunder & Nuclear Energy is
Released as heat
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Power Generation ThermodynamicsEnergy
Kinetic Energy of Air is harnessed by Wind Mills to produceElectricity.
Energy of Waves of See is Converted into Electrical Energy byfloating turbines.
Geo Thermal Energy under Earth crest s used to roduce ElecricalEnergy.
Immense Radiations of Sun are tapped to produce heat well asElectricity.
Power Kites are Seeming successful poducing MW Generation.
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Power Generation ThermodynamicsNew Energy Horizon
To Cop With upcoming Energy Crises &R
isisng Energy Demandsfollowing fields are currently under devolpement are migh be stateof the art in upcoming Decades.
Geo Magnets
Gravity EnergyCold Fusion
Photon fired power plats
Photosynthesis
Hydrogen Devolvement
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Power Generation Thermodynamics
Applied Thermodynamics
Science Deals With Heat, Work & Properties of SystemIt is concerned with means necessary to convert heat from
available sources (Fossil fuels) into Mechanical Energy.
Heat
Form of Energy, transformable from one body to other.Thermal Equilibrium.
System
Collection of matter with Identifiable boundaries.
e.g cylinder of engine during Expansion Stroke
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Power Generation Thermodynamics
Close System
Heat Engine
Open System
Fluid in turbine
Pressure
The pressure of system is the force on unit area f its boundries
Pascal 1Pa= 1N/m2
1 bar = 105 N/m2 = 105 Pa
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Power Generation Thermodynamics
Multiples and sub multiples
Multiplying Factor Prefix Symbol
1012 Tera T
109 Giga G
106 Mega M
103 Kilo K
10-3 mili m
10-6 micro u
10-9 nano n
10-12 pico p
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Power Generation Thermodynamics
1st Law of Thermodynamics
When a system goes into complete cycle net heat supplied + network input is zero.
Q+ W=0
2nd Law of Thermodynamics
In any Complete cycle the gross heat supplied + net work input
must be grater than zero.
Q1 > -W
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Power Generation Thermodynamics
Forward Heat Engine
First Law of Thermodynamics
Q1+Q2+W=0
Second Law of Thermodynamics
Q1 > -W
100 unit > -30 Units
Cycle Efficiency
= -W/ Q1
= 30/100 = 0.3
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Power Generation Thermodynamics
Reversed Heat Engine
First Law of Thermodynamics
Q1+Q2+W=0
Second Law of Thermodynamics
It is impossible to construct a device
that
operating in cycle will produce no effect
Other than the transfer of heat from a cooler body to hotter
body.
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Power Generation Thermodynamics
Conventional Power Plant:
Receiving fuel energy (F)Producing Work (W)
Rejecting Heat (QA)
Basic Power Plant
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Power Generation Thermodynamics
Objectives:
Least fuel Input for Given outputEconomically beneficial
Minimizing fuel cost
Key Objective
Capital Cost of Achieving High efficiency has to be accessed
And balanced against resulting saving in fuel costs.
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Power Generation Thermodynamics
Conventional Power Plant
Closed Cyclic Power Plant (Heat Engines)
Open Circuit Power Plants
Discussion is restricted to plants in which flow is steady
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Power Generation ThermodynamicsClosed Cyclic Power Plant (Heat Engines):
Fluid passes continuously round a closed circuit
Through a thermodynamic cycle
Heat QB is received from source at THigh
Heat QA is Rejected to sink at Tlow
Work (W) output
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Power Generation Thermodynamics
Closed Cyclic Power Plant (Heat Engines)
Fig. 2 Closed Circuit gas turbine Power Plant
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Power Generation Thermodynamics
Closed Cyclic Power Plant (Heat Engines)
Dotted Chain Control Surface Y surrounds
Cyclic Gas turbine
Compressor
Heater
Cooler
Power to Generator
Dotted Chain Control Surface Z surrounds
Open Control Surface
Combustion Chamber
Air fuel Mixture
Exhaust Gases
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Power Generation Thermodynamics
Closed Cyclic Power Plant (Heat Engines)
Dotted Chain Control Surface Z surrounds
Air fuel input
Heat is produced in Combustion Chamber
Heat QB is transferred from Z to Y
Exhaust gases
Dotted Chain Control Surface Y surrounds
Cyclic Gas turbine
Compressor
Heater
Cooler
Power to Generator
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Power Generation Thermodynamics
Closed Cyclic Power Plant (Heat Engines)
Dotted Chain Control Surface Z surrounds
Air fuel input
Heat is produced in Combustion Chamber
Heat QB is transferred from Z to Y
Exhaust gases
Dotted Chain Control Surface Y surrounds
Cyclic Gas turbine
Compressor
Heater
Cooler
Power to Generator
Turbine
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Power Generation Thermodynamics
Open Circuit Gas Turbine Plant
Usually Gas Turbine Operate n Open Circuit with Internal Combustion
Burning n Combustion Chamber
Turbine done work
Compressor is al being run by Turbine
Exhaust Gases.
Performance is accessed by treating it as equivalent to closed cyclic power
plant but with most care
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Power Generation Thermodynamics
The Joule-Brayton (JB) Constant Pressure
The Constant Pressure Closed cycle is the basis of the cyclic gas
turbine power plant, with steady flow of air(or gas) through a
compressor, heater, turbine, cooler, within closed circuit.
Heat is supplied at constant pressure and rejected at constant
pressure.
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Power Generation Thermodynamics
Combined Plants
UpperTapping Thermodynamic cycle
Produces power, but part of all its heat
Rejected Is used in supplying heat to
bottom cycle.
The Upper is Open Circuit Gas Turbine
Lower is closed Gas Tubine
Togater they form
Combind cycle gas turbine (CCGT) plant.
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Power Generation Thermodynamics
Combined Plants
The objective of combining two power
plants in this way is to obtain greater
Work output for a given supply of heat
or fuel energy.
This is achieved by converting some of
the heat rejected by the upper plant into extra work in thelower plant.
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Power Generation ThermodynamicsCombined Heat & Power Plants (CHP)
The term cogeneration is sometimes used
to describe a combined power plant,
but itis better used for a
combined hear and power (CHP)plant.
Now the fuel energy is converted
partly into (electrical) work (W)
and partly into useful heat (Qu)t a low
temperature, But higher than ambient.The non-useful heat rejected is Qw.
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Power Generation ThermodynamicsCriteria for the performance of power plants
Closed Cycle Power Plant
For a cyclic gas turbine plant in which fluid
is circulated continuously within the plant
(e.g. the plant enclosed within the
control surface Y).
one criterion ofperformance is simply
the thermal or cycle efficiency.
= W/ QB
W= net workQB is heat supplied,
W & QBis may be measured for a Mass of
Fluid M
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Power Generation ThermodynamicsCriteria for the performance of power plants
Closed Cycle Power Plant
The heat supply to the cyclic gas turbine
power plant, comes from the control
surface Z.
Within this second control surface,
a steady-flow heating device is supplied
With reactants (fuel and air) and it
discharges the products of combustion.
We may define a second efficiency for the 'heating device'(or boiler) efficiency;
= QB/ F = QB/Mf [CV]o
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Power Generation ThermodynamicsCriteria for the performance of power plants
[CV], is its calorific value per unit mass of fuel for the
ambient temperature (To at which
the reactants enter.
Mf[CV] = [-AH0] = HR0 Hpo, Change in Enthapy
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Power Generation ThermodynamicsCriteria for the performance of power plants
Overall Efficiency
0= W/ F =(W/ QB)(QB/ F)
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Power Generation ThermodynamicsEfficiency of an Open Circuit Gas Turbine Plant
For an open circuit (non-cyclic) gas turbine plant a different criterion
of performance is sometimes used-the rational efficiency (m)
This is defined as the ratio of
the actual work output to the maximum work output that can be
achieved between the reactants, each at pressure (po) and
temperature (To) of the environment, and products each at the same
po, To. Thus
R= W/ Wmax
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Power Generation ThermodynamicsIdeal Carnot Power Plant
The second law of thermodynamics may be used to show that a cyclic
heat power plant (or cyclic heat engine) achieves maximum efficiencyby operating on a reversible cycle
called the Carnot cycle for a given (maximum) temperature of supply
(T-) and given minimum) temperature of heat rejection (Tmin).Such a
Carnot power plant receives all itsheat (QB) at the maximum temperature @.e. TB = Tmin) and rejects all
its heat(QA) at the minimum temperature (i.e. TA = Tmin); the other
processes are reversible and adiabatic
CAR= W/ QB =(QB- QA / QB)=(QB- QA / QB)
(Tmax-Tmin)/Tmax
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Power Generation ThermodynamicsIdeal Carnot Power Plant
The Carnot engine (or cyclic power plant) is a useful
hypothetical device in the study of the thermodynamics of
gas turbine cycles, for it provides a measure of the best
performance that can be achieved under the given
boundary conditions of temperature.
In his search for high efficiency,
the designer of a
gas turbine power plant will attempt
to emulate these features of the Carnot cycle.