This document provides an overview of wind energy fundamentals and design considerations for wind turbines. It discusses how wind power depends on air volume, velocity, and density. It also explains power coefficients and the Betz limit for wind turbine efficiency. The two main types of wind turbines - horizontal axis and vertical axis - are described. Key design considerations for wind turbines include the number of blades, blade composition and construction, and factors that influence turbine performance like airfoil shape, twist, taper, tip-speed ratio, and rotor solidity.
LOW EXPENSE VERTICAL AXIS WIND TURBINE USING PERMANENT MAGNETSIAEME Publication
Wind turbines are devices that convert the wind's kinetic energy into electrical power. The result of over a millennium of windmill development and modern engineering, today's wind turbines are manufactured in a wide range of horizontal axis and vertical axis types. The smallest turbines are used for applications such as battery charging for auxiliary power. Slightly larger turbines can be used for making small contributions to a domestic power supply while selling unused power back to the utility supplier via the electrical grid. Arrays of large turbines, known as wind farms, have become an increasingly important source of renewable energy and are used in many countries as part of a strategy to reduce their reliance on fossil fuels.
* Introduction to Wind Energy
* History of Wind Energy
* Generation of Wind Energy
* Details of Wind Turbines
* Wind Measurement
* Advantages and Disadvantages
* Wind Power Plants in Pakistan.
LOW EXPENSE VERTICAL AXIS WIND TURBINE USING PERMANENT MAGNETSIAEME Publication
Wind turbines are devices that convert the wind's kinetic energy into electrical power. The result of over a millennium of windmill development and modern engineering, today's wind turbines are manufactured in a wide range of horizontal axis and vertical axis types. The smallest turbines are used for applications such as battery charging for auxiliary power. Slightly larger turbines can be used for making small contributions to a domestic power supply while selling unused power back to the utility supplier via the electrical grid. Arrays of large turbines, known as wind farms, have become an increasingly important source of renewable energy and are used in many countries as part of a strategy to reduce their reliance on fossil fuels.
* Introduction to Wind Energy
* History of Wind Energy
* Generation of Wind Energy
* Details of Wind Turbines
* Wind Measurement
* Advantages and Disadvantages
* Wind Power Plants in Pakistan.
Wind turbines,the most essential tool that produces energy with out causing any harm to the nature
It is best technique to convert the wind energy to electrical energy
Wind power or wind energy is the use of wind to provide the mechanical power through wind turbines to turn electric generators and traditionally to do other work, like milling or pumping. Wind power is a sustainable and renewable energy, and has a much smaller impact on the environment compared to burning fossil fuels.
Wind Power Plant Presentation (Seminar PPT) Jay Sonar
Power Point Presentation On Wind Energy and Wind Turbine & Its Components. Full Seminar Presentation For Diploma And Engineering Students. Easy and Understandable Format.
Thanks. Follow & keep Presenting.
Wind turbines,the most essential tool that produces energy with out causing any harm to the nature
It is best technique to convert the wind energy to electrical energy
Wind power or wind energy is the use of wind to provide the mechanical power through wind turbines to turn electric generators and traditionally to do other work, like milling or pumping. Wind power is a sustainable and renewable energy, and has a much smaller impact on the environment compared to burning fossil fuels.
Wind Power Plant Presentation (Seminar PPT) Jay Sonar
Power Point Presentation On Wind Energy and Wind Turbine & Its Components. Full Seminar Presentation For Diploma And Engineering Students. Easy and Understandable Format.
Thanks. Follow & keep Presenting.
Design of PVC Bladed Horizontal Axis Wind Turbine for Low Wind Speed RegionIJERA Editor
The Project is aimed at designing a wind turbine that can be able to build by Laypersons, using readily available material which is feasible & affordable to provide much needed electricity. Since most of the high wind power density regions in the zone of high wind speed are already being tapped by large scale wind turbine and so it required creating a large scope for the development of low wind speed turbines. Our study focuses primarily on designing the blade for tapping power in the regions of low wind power density. The aerodynamic profiles of wind turbine blades have major influence on aerodynamic efficiency of wind turbine. This can be achieved by comparing the effectiveness of a crude blade fashioned from a different Size, Material & standard of PVC drainage pipe which are easily available in market. It can be evaluated by performing experimental analysis, data collection & its evaluation on different type & size of PVC Pipe & preparing an analytical tool for best Design.
Investigate the effect of blade tip geometry on the performance Vertical Axis...Mohamed Sabry Mohamed
Fluids always flow from high-pressure region to low pressure region, this is the principle of the
airflow around the airfoil and this can create vortices at the trailing edge which reduce the lift
and increase the induced drag and turbulence around the blade turbine. Winglets are a
different method to change the geometry of the blade tip which in turn can affect the whole
performance of the turbine by reducing the vortices or by enhancing the turbine power
coefficient. This project experimentally and numerical investigates the effect of winglets on the
aerodynamic performance of the vertical axis wind turbine (H-Rotor).
3. Introduction
The wind is a free, clean, and inexhaustible energy source.
It has served mankind well for many centuries by propelling ships and driving
wind turbines to grind grain and pump water.
Interest in wind power lagged, however, when cheap and plentiful petroleum
products became available after World War II.
The high capital costs and the uncertainty of the wind placed wind power at an
economic disadvantage.
Then in 1973, the Arab nations placed an embargo on petroleum.
The days of cheap and plentiful petroleum were drawing to an end.
4. People began to realize that the world’s oil supplies would not last
forever and that remaining supplies should be conserved for the
petrochemical industry.
The use of oil as a boiler fuel, for example, would have to be
eliminated.
Other energy sources besides oil and natural gas must be developed,
wind energy being one of them.
Global wind power potential is of the order of 11,000 GW.
It is about 5 times the global installed power generation capacity.
This excludes offshore potential as it is yet to be properly estimated.
5. About 25,000 MW is the global installed wind power capacity.
It is about 1% of global installed power generation capacity.
Wind produces about 50 billion kWh per year globally with the
average utilization factor of 2000 hours per year.
Global wind power growth trends from 1980 to 1995 are shown in
Figure 1 and the country wise details of installed wind power
capacity from 1998 to 2001 is given in Table 1.
6.
7.
8. Power in Wind
Wind Power depends on:
amount of air (volume)
speed of air (velocity)
mass of air (density) flowing through the area of interest (flux)
Kinetic Energy definition:
KE = ½ * m * 𝑣2
Power is K.E per unit time: P = ½ * 𝑚 * 𝑣2
where 𝑚 = mass flux
9. But 𝑚 = ρ* A * v
Hence P = ½ * ρ * A * 𝑣3
So, Power cube of velocity
Power air density
Power rotor swept area A= π*𝒓 𝟐
10. Power Coefficient
Power Coefficient, Cp, is the ratio of power extracted by the
turbine to the total contained in the wind resource Cp = PT/PW
Turbine power output
PT = ½ * ρ * A * 𝑣3 * Cp
The Betz Limit is the maximal possible Cp = 16/27
59% efficiency is the BEST a conventional wind turbine can do in
extracting power from the wind
11. Types Of Wind Turbines
A wind turbine is a machine for converting the kinetic energy in wind
into mechanical energy.
Wind turbines are classified into two general types:
1. Horizontal Axis and
2. Vertical Axis.
12. Horizontal Axis Wind Turbine
A horizontal axis machine has its blades rotating on an axis parallel
to the ground.
Due to this arrangement the generator and gearbox are located above
the ground, making service and repair difficult.
HAWTs are to be pointed into the wind, which makes wind-sensing
and orientation mechanisms necessary.
13.
14. Vertical Axis Wind Turbine
Vertical-axis wind turbines (VAWTs) are a type
of wind turbine where the main rotor shaft is set
traverse, not necessarily vertical, to the wind and
the main components are located at the base of the
turbine.
This arrangement allows the generator and gearbox
to be located close to the ground, facilitating
service and repair.
VAWTs do not need to be pointed into the
wind, which removes the need for wind-sensing
and orientation mechanisms.
15. Advantages of vertical axis wind turbines
They are Omni-directional and do not need to track the wind. This
makes them much more reliable due to them not requiring a complex
mechanism and motors to Yaw the rotor and pitch the blades.
The gearbox of a VAWT take much less fatigue when compared to
that of a HAWT, should they require it, replacement is less costly and
logistically simpler as the gearbox is easily accessible at ground
level.
VAWTs do not need to track the wind to produce energy as they are
omnidirectional, any reported inefficiencies are in fact cancelled out
by the fact that a VAWT can take advantages of turbulent and gusty
winds, these winds are not harvested by HAWTs, in fact this type of
wind causes accelerated fatigue for HAWTs.
16. VAWTs wings (Darius type) have a constant chord and so easier to
manufacture, when compared to the complex shape and structure of
the blades of a HAWT.
VAWTs can be packed much closer together in wind farms, meaning
improved power per area of land used.
VAWTs could be installed on existing wind farms below existing
HAWTs, this would improve the efficiency of existing wind farms.
Research at Caltech has also shown that carefully designing wind
farms using VAWTs can result in power output ten times as great as a
HAWT wind farm the same size.
VAWTs can use a screw pile foundation, meaning a huge reduction in
the carbon cost of an installation, a reduction in road transport
(concrete) during installation, and are fully recyclable at the end of the
installations life.
17. Disadvantages of vertical axis wind
turbines
The blades of a VAWT were fatigue prone due to the wide variation in applied
forces during each rotation.
This has been overcome by the use of modern composite materials and
improvements in design; the use of aerodynamic wing tips causes the spreader
wing connections to have a static load.
The vertically-oriented blades used in early models twisted and bent during
each turn, causing them to crack
. Over time, these blades broke apart, sometimes leading to catastrophic
failure. VAWTs have proven less reliable than HAWTs.
18. Design Considerations
Number of Blades – One
Rotor must move more rapidly to capture same amount
of wind
Gearbox ratio reduced
Added weight of counterbalance negates some
benefits of lighter design
Higher speed means more noise, visual, and
wildlife impacts
Blades easier to install because entire rotor can be
assembled on ground
Captures 10% less energy than two blade design
Ultimately provide no cost savings
19. Number of Blades - Two
Advantages & disadvantages similar
to one blade
Need teetering hub and or shock
absorbers because of gyroscopic
imbalances
Capture 5% less energy than three
blade designs
20. Number of Blades - Three
Balance of gyroscopic forces
Slower rotation
increases gearbox & transmission
costs
More aesthetic, less noise, fewer
bird strikes
22. Blade Composition
Metal
Steel
Heavy & expensive
Aluminum
Lighter-weight and easy to work with
Expensive
Subject to metal fatigue
23. Blade Construction
Fiberglass
Lightweight, strong, inexpensive,
good fatigue characteristics
Variety of manufacturing processes
Cloth over frame
Pultrusion
Filament winding to produce spars
Most modern large turbines use
fiberglass
24. Large Wind Turbines
450’ base to blade
Each blade 112’
Span greater than 747
163+ tons total
Foundation 20+ feet deep
Rated at 1.5 – 5 megawatt
Supply at least 350 homes
25.
26. Lift & Drag Forces
The Lift Force is perpendicular to
the direction of motion. We want to
make this force BIG.
The Drag Force is parallel to the
direction of motion. We want to
make this force small.
α = low
α = medium
<10 degrees
α = High
Stall!!
27. Airfoil Shape
Just like the wings of an airplane,
wind turbine blades use the airfoil
shape to create lift and maximize
efficiency.
28. Twist & Taper
Speed through the air of a point on
the blade changes with distance
from hub
Therefore, tip speed ratio varies as
well
To optimize angle of attack all
along blade, it must twist from root
to tip
Fast
Faster
Fastest
29. Tip-Speed Ratio
Tip-speed ratio is the ratio of the speed of the
rotating blade tip to the speed of the free
stream wind.
There is an optimum angle of attack which
creates the highest lift to drag ratio.
Because angle of attack is dependent on wind
speed, there is an optimum tip-speed ratio
ΩR
V
TSR =
Where,
Ω = rotational speed in radians /sec
R = Rotor Radius
V = Wind “Free Stream” Velocity
ΩR
R
30. Performance Over Range of Tip Speed Ratios
• Power Coefficient Varies with Tip Speed Ratio
• Characterized by Cp vs. Tip Speed Ratio Curve
0.4
0.3
0.2
0.1
0.0
Cp
121086420
Tip Speed Ratio
31. Betz Limit
All wind power cannot be captured by
rotor or air would be completely
still behind rotor and not allow
more wind to pass through.
Theoretical limit of rotor efficiency is
59%
Most modern wind turbines are in the
35 – 45% range
32. Rotor Solidity
Solidity is the ratio of total rotor planform area to total
swept area
Low solidity (0.10) = high speed, low torque
High solidity (>0.80) = low speed, high torque
A
R
a
Solidity = 3a/A
33. References
Wind Energy Conversion Systems, ENERGY SYSTEMS
ENGINEERING,IIT BOMBAY.
MIT Wind Energy Group & Renewable Energy Projects in Action.
Wikipedia
Wind Turbine Design Cost and Scaling Model, L. Fingersh, M. Hand,
and A. Laxson.
Guidelines for Design of Wind Turbines − DNV/Risø.
Wind Turbine Power Calculations, RWE npower renewables,
Mechanical and Electrical Engineering, Power Industry.
Wind Turbine Blade Design, Classroom Activities for Wind Energy
Science.
