Boiler draught refers to the pressure difference between the air inside a boiler furnace and the outside air, which causes the flow of air and flue gases through the boiler. This pressure difference is necessary for proper combustion of fuel and removal of flue gases. Draught can be produced naturally through the use of a chimney, or artificially through mechanical fans or steam jets. Forced draught uses a fan before the furnace to push air and gases through, while induced draught uses a fan at the chimney to pull gases through. Balanced draught combines the two. Mechanical draught allows better control of the pressure but has higher costs than natural or steam jet draught.
PPT describes the engine performance parameters of the I.C. engine.
Engine performance is an indication of the degree of success of the engine performs its assigned task, i.e. the conversion of the chemical energy contained in the fuel into the useful mechanical work. The engine performance is indicated by the term efficiency, η. Five important engine efficiencies and other related engine performance parameters are:
Power
Indicated Thermal Efficiency (ηith)
Brake Thermal Efficiency (ηbth)
Mechanical Efficiency (ηm)
Volumetric Efficiency (ηv)
Relative Efficiency or Efficiency Ratio (ηrel)
Mean Effective Pressure (Pm)
Specific Fuel Consumption (sfc)
Fuel-Air or Air-Fuel Ratio (F/A or A/F)
Calorific Value (CV)
Power:-
The main purpose of running an engine is to obtain mechanical power.
Brake Power (B.P.)
The power developed by an Engine at the output shaft is called the brake power.
Brake Power= Brake Workdone/Time
B.P.=BWD/sec.
Indicated power (I.P.)
The total power developed by Combustion of fuel in the combustion chamber is called indicated power.
Indicated Power= Indicated Workdone/Time
I.P.=IWD/sec.
Frictional Power (F.P.)
The difference between I.P. and B.P. is called frictional power (f.p.).
FP = IP – BP
Thermal Efficiency (ηth)
Thermal efficiency is the ratio of Power to energy supplied by the fuel.
ηth= Power/ Energy
In I.C. Engine, thermal efficiency can be classified into two categories i.e.
Indicated Thermal Efficiency (ηith)
Indicated thermal efficiency is the ratio of indicated power to the heat supplied or added.
ηith= IP/Qs
2. Brake Thermal Efficiency (ηith)
Brake Thermal Efficiency is the ratio of brake power to the heat supplied or added.
ηbth= BP/Qs
Volumetric Efficiency (ηv)
This is one of the most important parameters which decide the performance of four-stroke engines. Four stoke engines have distinct suction stoke, volumetric efficiency indicates the breathing ability of the engine.
Volumetric efficiency is defined as the ratio of actual flow rate of air into the intake system to rate at which the volume is displaced by the system.
ηv= (푚 ̇"a/a" )/(푉푑푖푠푝푎푐푒푑 푋 푁/2)
"a"= Inlet density is taken atmospheric air density
N= Number of the cylinder in use
Definition of Supercharging ,
Effect of Supercharging ,
Need of Supercharging ,
Types of Supercharging
1) Centrifugal Supercharger
2) Rootes Supercharger
3) Vane Supercharger ,
Advantages & Disadvantages of Supercharging
PPT describes the engine performance parameters of the I.C. engine.
Engine performance is an indication of the degree of success of the engine performs its assigned task, i.e. the conversion of the chemical energy contained in the fuel into the useful mechanical work. The engine performance is indicated by the term efficiency, η. Five important engine efficiencies and other related engine performance parameters are:
Power
Indicated Thermal Efficiency (ηith)
Brake Thermal Efficiency (ηbth)
Mechanical Efficiency (ηm)
Volumetric Efficiency (ηv)
Relative Efficiency or Efficiency Ratio (ηrel)
Mean Effective Pressure (Pm)
Specific Fuel Consumption (sfc)
Fuel-Air or Air-Fuel Ratio (F/A or A/F)
Calorific Value (CV)
Power:-
The main purpose of running an engine is to obtain mechanical power.
Brake Power (B.P.)
The power developed by an Engine at the output shaft is called the brake power.
Brake Power= Brake Workdone/Time
B.P.=BWD/sec.
Indicated power (I.P.)
The total power developed by Combustion of fuel in the combustion chamber is called indicated power.
Indicated Power= Indicated Workdone/Time
I.P.=IWD/sec.
Frictional Power (F.P.)
The difference between I.P. and B.P. is called frictional power (f.p.).
FP = IP – BP
Thermal Efficiency (ηth)
Thermal efficiency is the ratio of Power to energy supplied by the fuel.
ηth= Power/ Energy
In I.C. Engine, thermal efficiency can be classified into two categories i.e.
Indicated Thermal Efficiency (ηith)
Indicated thermal efficiency is the ratio of indicated power to the heat supplied or added.
ηith= IP/Qs
2. Brake Thermal Efficiency (ηith)
Brake Thermal Efficiency is the ratio of brake power to the heat supplied or added.
ηbth= BP/Qs
Volumetric Efficiency (ηv)
This is one of the most important parameters which decide the performance of four-stroke engines. Four stoke engines have distinct suction stoke, volumetric efficiency indicates the breathing ability of the engine.
Volumetric efficiency is defined as the ratio of actual flow rate of air into the intake system to rate at which the volume is displaced by the system.
ηv= (푚 ̇"a/a" )/(푉푑푖푠푝푎푐푒푑 푋 푁/2)
"a"= Inlet density is taken atmospheric air density
N= Number of the cylinder in use
Definition of Supercharging ,
Effect of Supercharging ,
Need of Supercharging ,
Types of Supercharging
1) Centrifugal Supercharger
2) Rootes Supercharger
3) Vane Supercharger ,
Advantages & Disadvantages of Supercharging
Actual cycles for internal combustion engines differ from air-standard cycles in many respects.
Time loss factor.
Heat loss factor.
Exhaust blow down factor.
A steam turbine is a prime mover in which the potential energy of the steam is transformed into kinetic energy and later in its turn is transformed into the mechanical energy of rotation of the turbine shaft
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled toa downstream turbine, and a combustion chamber in-between. Energy is added to the gas stream in the combustor, where fuel is mixed with air and ignited. In the high-pressure environment of the combustor, combustion of the fuel increases the temperature. The products of the combustion are forced into the turbine section
Visit https://www.topicsforseminar.com to Download
boiler accessories, basics of economizer, types of economizer, air preheater, types of air preheater, reheater, basics of superheater, types of superheater.
Know Everything you want to know about steam nozzles(Turbine Excluded).Know more about De-Laval Nozzles and How we achieve Supersonic velocity from nozzles.Also get to know about other essentials such as Critical pressure ratio and Saturated Flow.You can use this ppt in your projects,journals.It is not copyright protected.
INTRODUCTION
THERMODYNAMIC CYCLE OF STEAM FLOW
RANKINE CYCLE (IDEAL , ACTUAL ,REHEAT)
LAYOUT OF STEAM POWER PLANT
MAJOR COMPONENTS AND THEIR FUNCTIONS
ALTERNATOR
EXCITATION SYSTEM
GOVERNING SYSTEM
Actual cycles for internal combustion engines differ from air-standard cycles in many respects.
Time loss factor.
Heat loss factor.
Exhaust blow down factor.
A steam turbine is a prime mover in which the potential energy of the steam is transformed into kinetic energy and later in its turn is transformed into the mechanical energy of rotation of the turbine shaft
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled toa downstream turbine, and a combustion chamber in-between. Energy is added to the gas stream in the combustor, where fuel is mixed with air and ignited. In the high-pressure environment of the combustor, combustion of the fuel increases the temperature. The products of the combustion are forced into the turbine section
Visit https://www.topicsforseminar.com to Download
boiler accessories, basics of economizer, types of economizer, air preheater, types of air preheater, reheater, basics of superheater, types of superheater.
Know Everything you want to know about steam nozzles(Turbine Excluded).Know more about De-Laval Nozzles and How we achieve Supersonic velocity from nozzles.Also get to know about other essentials such as Critical pressure ratio and Saturated Flow.You can use this ppt in your projects,journals.It is not copyright protected.
INTRODUCTION
THERMODYNAMIC CYCLE OF STEAM FLOW
RANKINE CYCLE (IDEAL , ACTUAL ,REHEAT)
LAYOUT OF STEAM POWER PLANT
MAJOR COMPONENTS AND THEIR FUNCTIONS
ALTERNATOR
EXCITATION SYSTEM
GOVERNING SYSTEM
The Thermal Power Station burns fuel & uses the resultant to make the steam, which derives the turbo generator. The Fuel i.e. coal is burnt in pulverized from. The pressure energy of the steam produce is converted into mechanical energy with the help of turbine. The mechanical energy is fed to the generator where the magnet rotate inside a set of stator winding & thus electricity is produced in India 65% of total power is generated by thermal power stations. To understand the working of the Thermal Power Station plant, we can divide the whole process into following parts.
mounting and accessories of boiler in eme Pratik Patel
it contain detail of element used in boiler for its working
it also teach the concept of mounting
nd it is helpfull for the student of engineering 1 st year
Introduction To Thermal Power Plant (Steam power plant)
GENERAL LAYOUT OF THERMAL POWER PLANT
COAL HANDLING PLANT
Power Plant cycles
1. Feed Water Cycle
2. Steam Cycle
3. Condensate Cycle
4. Cooling Water Cycle
5. Air And Flue Gas Cycle
Important Power plant equipment
Deaerator
Boiler Feed Water Pump
Heaters
Economiser
Boiler
BOILER DRUM ( STEAM DRUM)
SUPER HEATER
TURBINE
CONDENSER
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
2. DEFINITION
Boiler draught may be defined as the small
difference between the pressure of outside air and
that of gases within a furnace or chimney at the
grate level, which causes flow of air/hot flue gases
to take place through boiler.
The draught is necessary to force air through the
fuel bed/ grate to aid in proper combustion of fuel
and to remove the products of combustion
i.e. flue gases to the atmosphere after they have
given their heat to water being evaporated in boiler.
3. Draught also provides velocity to flue gases and so
increases the heat transfer co-efficient in the boiler.
Thus draught is essentially required in a boiler and
can be produced by a number of methods.
4.
5. NATURAL DRAUGHT
Natural draught is obtained naturally by the use of
a chimney.
Chimney is a conical shape vertical tubular steel or
masonry or concrete structure having a large
height.
The flue gases after transferring their heat in the
boiler are guided by chimney to a considerable
height in the atmosphere.
As chimney has a large height and is the only
outlet from boiler, it remains filled by hot flue gases.
6. These exhaust gases, however have given their
heat to water in the boiler, are still hotter than the
boiler room air.
Due to this, the exhaust gases are lighter in weight
than outside air and so lifts up naturally in the
chimney and finally escape out in the atmosphere
from top of the chimney.
As the flue gases lift up in the chimney, more gases
from fuel bed flow towards chimney to take their
place.
During this process, they first flow through the
boiler and do the job of heating of water and
produce steam.
7. As flue gases flow through boiler and then to
chimney, fresh air from outside naturally enters the
boiler and help in burning of fuel and production of
hot flue gases.
So, in this way, a small pressure difference is
naturally created between the base of chimney and
the air inlet point of boiler because of density
difference between hot flue gases inside the
chimney and fresh colder air outside.
This pressure difference is called natural draught,
because it is produced naturally.
8.
9. ARTIFICIAL DRAUGHT
When the draught is produced by some external
agency i.e. mechanical fan/blower or by steam jet
itself, it is called artificial draught.
In modern commercial boilers, more value of
draught is required to increase the heat transfer co-
efficient and hence the thermal efficiency.
So, artificial draught is must to use to overcome the
flow resistance offered by large flue passages.
10. FORCED DRAUGHT
It is a positive pressure draught.
The fan is installed at the base of the boiler before
grate which forces the outside air through fuel bed,
furnace and air pre-heater and then flue gases
through flue passage, economizer etc.
The enclosure for the furnace has to be very tightly
sealed so that gases from the furnace do not leak
out in the boiler house.
11. INDUCED DRAUGHT
In this system a fan or blower is located at or near
the base of the chimney which creates a partial
vacuum in the furnace and flue passage.
Thus the air and flue gases are drawn through the
boiler due to comparatively higher pressure of
outside air.
It is convenient to produce induced draught and
like in forced draught, any type of fan/blower may
be used.
12. BALANCED DRAUGHT
It is a combination of forced and induced draught.
Forced draught fan overcomes the resistance in air
pre-heater and grate.
Induced draught fan overcomes draught losses
through boiler, economizer and connecting flue
passages etc.
Depending on the type of fuel burnt and type of
boiler, the fan or blower used may be of any type as
radial or axial etc.
13. ADVANTAGES OF MECHANICAL DRAUGHT
It is more economical and its control is easy.
Desired value of draught can be produced by
mechanical means which cannot be produced by
means of natural draught.
It increases the rate of combustion by which low
grade fuel can also be used.
It reduces the smoke level and increases the heat
transfer co-efficient on flue gases side thus
increases the thermal efficiency of boiler.
It saves the energy and the heat of flue gases can
be best utilized by it.
14. DISADVANTAGES OF MECHANICAL
DRAUGHT
Initial costs of mechanical draught system are high.
Running cost is also high due to requirement of
electricity but that is easily compensated by the
savings in fuel consumption.
Maintenance cost is also on higher side.
Noise level of boiler is also high due to noisy
fan/blower etc.
15. STEAM JET DRAUGHT
It is a very simple and easy method of producing
artificial draught without the need of an electric
motor.
Steam under pressure is available in the boiler.
When a small portion of steam is passed through a
jet or nozzle, pressure energy converts to kinetic
energy and steam comes out with a high velocity.
This high velocity steam carries, along with it, a
large mass of air or flue gases and makes it to flow
through boiler.
16. Steam jet is directed towards a fixed direction and
carries all its energy in kinetic form.
It creates some vacuum in its surroundings and so
attracts the air of flue gases either by carrying along
with it.
Thus it has the capacity to make flow of the flue
gases either by carrying or inducing towards
chimney.
17.
18. FORCED STEAM JET DRAUGHT
Steam from the boiler after having been throttled to
a gauge pressure of 1.5 to 2 bar is supplied to the
jet or nozzles installed in ash pit.
The steam emerging out of nozzles with a great
velocity drags air along the fuel bed, furnace, flue
passage and then to the chimney.
Here steam jet is forcing the air and flue gases to
flow through boiler hence it is forced steam jet
draught.
19. INDUCED STEAM JET DRAUGHT
The jet of steam is diverted into smoke box or
chimney.
The kinetic head of the steam is high but static
head is low i.e. it creates a partial vacuum which
draws the air through the grate, ash pit, flues and
then to motor box and chimney.
This type of arrangement is employed in locomotive
boilers.
Here steam jet is sucking the flue gases through
boiler, so it is Induced Steam Jet Draught.
20. ADVANTAGES
It is quite simple and cheap.
It has the capability of using low grade fuels.
It occupies very less space.
Initial cost is low.
Maintenance cost is low.
Exhaust steam from steam engine or turbine can be
used easily in Steam Jet Draught.
21. DISADVANTAGES
It can operate only when some steam is
generated.
Draught produced is very low.
22. DRAUGHT LOSSES
Loss due to the frictional resistance offered by flue
gas passage to the flow of flue gases.
Loss due to bends in gas flow circuit, which also
offer flow resistance.
Loss due to friction head in grate, economizer,
super heater etc.
Loss due to flow resistance offered by chimney.
Loss due to imparting some velocity to flue gases,
which is required to increase heat transfer in boiler
and also to throw away the flue gases from
chimney.