|
What Is The Effect of Blade Length on Electrical
Output of a Windmill?
|
Researched by Ethan B.
2001-02 |
|
PURPOSE
The purpose of this experiment was to determine how the length of blade
in a windmill would affect the power output.
I became interested in this idea when I heard of the blackouts in California.
I knew that since there was a growth in the population that they would
need more electricity.
The information gained from this experiment would be able to help invent
a new windmill that could generate more electricity with optional blade
length.
HYPOTHESIS
My hypothesis was that the longer blade would make more electricity.
I based my hypothesis on the design of cylinder shape windmill that
uses its wide shape to catch more wind. So if the blades were longer it
would catch more wind to make more electricity.
Top of page
EXPERIMENT DESIGN
The constants in this study were:
Wind speed
Number of blades (3)
Windmill design
Distance from wind source
Size, type of generator
Material of the windmills
Voltmeter to measure electric output
The manipulated variable was the length of the blades on the windmills.
There were five different lengths.
The responding variable was the output of the electricity of the windmills.
To measure the responding variable I used a voltmeter by hooking it
up to output wires generator.
Top of page
MATERIALS
QUANTITY |
ITEM DESCRIPTION |
| 1 |
Fan |
| 1 |
Ruler |
| 1 |
Voltmeter |
| 1 |
Motor/Generator |
| 1 |
Square block of wood |
| 1 |
Drill |
| 1 |
Hot glue gun |
| 3 |
Metal blades |
Top of page
PROCEDURES
A. Build a windmill
1. Gather all the materials.
2. Cut three metal triangles and make the distance from the canter
to the corners the length of the blade you need.
3. Drill a small hole in to the direct center of the metal triangle.
4. Then, cut the extra metal off and make the blades 120° apart.
5. Bend the blades so they can catch the wind.
B. Building the base.
1. Drill two small holes on each side of a 4x4x1-in. block of wood
to connect the base of the windmill.
2. Put two metal sticks through the hole and wrap them around the base
3. Connect the back wires of the generator to the voltmeter to measure
the electric output
C. Conduct the experiment
1. Get a blow dyer and set it 30 cm away from where you set the windmill.
2. Turn the blades at a 45degree angle.
3. Turn on the fan to the highest and aim directly at the blades.
4. Run fan for 2 minutes.
5. Record the results in journal.
6. Change blades for each experiment.
7. Then repeat Step C for every blade size.
Top of page
RESULTS
The original purpose of this experiment was to determine how the length
of blade in a windmill would affect the power output.
The results of the experiment were that the 9-cm. blades created the
most electricity. Also the 15 cm. was too heavy to pick up enough speed,
and the 5 cm. did not have long enough blades surface to catch enough wind.
See the table and graph below.
CONCLUSION
My hypothesis was that the longer blade would make more electricity.
The results indicate that this hypothesis should be rejected.
Because of the results of this experiment, I wonder if the weight of
the blades would affect the amount of spin.
If I were to conduct this project again I would have made the base out
of something stronger and more open to wind flow. Also I would have made
the blades out of balsa wood instead of metal. Plus I would have run more
trials and had more blade lengths, because a centimeter could make a difference.
I would also have made sure that every blade weighed the same.
Top of Page
| RESEARCH REPORT
Intro
Energy is one of the main things that humans need to survive. Humans
need energy to power most of the things in their house, to give heat for
the water heater and to make a refrigerator stay cold. Also people need
to have energy to have light in their houses and to run the television
and computer. Another major thing energy is used for is manufacturing of
cars, buildings, electronics and some factories that ship and package food.
History
The first windmills were made and used in Persia, now known as Iran,
in 500 A.D. They used the windmills to grind grain to make various foods.
Alexander the Great described a windmill that he saw in the 2nd century
A.D. Then in 1000 A.D. France used windmills to grind grain and to
pump water. These windmills had a horizontal shaft. At the same time the
Dutch used windmills to drain dikes. These windmills used cloths on long
wooden arms that had the shape of a blade. It had slats to make the blades
spin in the same way as the wind was blowing. Then in the 19th century
thousands of windmills were placed in America but they were still used
for irrigation. Eventually Europe stopped seeing the advantages of the
windmill and gave them up, and started to use steam-powered engines.
In the 1800’s and the 1900’s American windmills were also used to pump
water. They had curved blades made of wood or steel that had a vane on
the back to move it in the direction of the wind. In 1854 Daienal Halliday
made a windmill that had a tank of water to fill at the back, which was
later replaced with a generator that makes electricity.
In the 1930’s through the 1950’s America’s need for electricity grew
and then in the 1970’s the idea of "Free energy of wind" came along. The
government gave the money needed to fund projects all over the United States.
By the 1980’s there were already 30 windmill companies. In 1995 13,437
windmills were set in California, but California is not always windy. Scientists
estimate there are 13 other states that would be better for windmills,
but the manufacturing would take a lot of money.
Types of Windmills
There are many types of windmills. Most of them have a horizontal or
a vertical shaft. A horizontal shaft is level to the ground or pointing
straight. A vertical shaft on the other hand is upright or little tilted.
There are many different models of windmills that were made all over
the world. One of them is the Tower windmill made in France. It has a stone
tower that has a wooden cap on top and on this cap are the blades and a
shaft. It has four to eight blades and they are about 10 to 30 ft long.
Another one of the most famous type is the Cylinder type. It can be used
in the water or the air. When there is no wind to move the windmill it
uses a motor and makes electricity for itself to keep on making electricity.
Along with the windmills that create energy there are also windmills
that keep cold air out of fields and keep the warm air in the air. It works
just the opposite way as the energy windmill does except it makes wind
instead of using it to make electricity. These windmills keep the fruits
in the fields from freezing or getting frostbite. There are also commercial
and industrial windmills. The commercial windmills generate about 2 to
10 kilowatts that can power your refrigerator. The industrial windmills
make about 4 megawatts.
Parts of Windmills
The windmill is made up of many parts. One of the most important parts
is the blade. The blade is set on a horizontal or vertical shaft. Then
the blades take in the wind and spin. Then the shaft turns with blades
and makes the metal gears inside the generator spin, which spins the generator.
Energy
Energy is usable heat or power. There are many ways to make electricity:
Solar, hydropower, wind power, and fossil fuels and also chemicals in batteries.
Electricity is the physical effect of charged electrons and protons.
Electricity is produced in many different ways. One is at a nuclear power
plant and another is from the sun into the solar panels. Another is from
dams and water turbines. Another is burning fossil fuels like coal, gasoline,
and oil. The last is wind power, which gathers electricity from the wind.
Some of the main dangers with producing electricity are pollution. The
worst pollution is nuclear waste. It either has to be buried in a safe
location, which could cause soil pollution. Or it can be dumped into the
sea, which could kill fish and might even kill some of the species in the
ocean. One bad thing about fossil fuels is that the smoke can pollute the
air and cause acid rain that could get into water supplies and pollute
the water. The smoke produced can also pollute the air itself and make
it harder for some animals to breath. The bad thing about building dams
is that the water behind it cannot be used and the migration of some fish
is cut off. Salmon for example in some places can not get through to the
river that leads them to their breeding areas. The only bad thing about
solar power is that it takes a lot of solar panels to make a lot of electricity.
There are two major things wrong with wind power. It can kill birds and
it makes loud noise that can bother some people. So the space for setting
the wind turbines is limited and the wind has to stay at a fairly constant
speed of 15 to 20 kilometers an hour.
Summary
Energy is one of the main things that humans need to survive. For we
need it to power things that keep food fresh and make any thing with electricity
work.
Top of page
|
Bibliography
Brown, Joseph E. "Windmills and Wind Power" Academic America Encyclopedia
Chandler, Gary & Graham, Kevin. Alternative Energy Sources Canada:
Fitzhenrey
Whiteshead. 1996.Pp 24-29.
Ghandalky, Adel A. "Wind Power". The World Book Encyclopedia .1999.
Gipe, Paul "Windmills". Encarta. 2001
Iliyn Alexandra Mary "Windmill." The World Book Encyclopedia. 1999.
Kardi, Gabor. "Wind Power." Compcans. 2001.
Lemone A., Margaret "Wind" The World Book Encyclopedia 1999
Manwell F. James "Windmills". Encarta. 2001.
Machines and Inventions Alexandra, Virginia: Time Life. Pp28.
"Windmill and Wind Turbine" World of Invention
"Wind Story" September 15,2001 http://www.energy.com
|
ACKNOWLEDGEMENTS
I would like to thank the following people. Without their help my project
would not of been possible.
I would like to thank my father for helping me make the windmill, and
helping me finding the materials.
I would like to thank my friends Cody, and Nick for giving me have
the need to finish the project.
I would also like to thank Mrs. Helms for helping me with any of the
problems I had, and giving me advice on what to fix and what to do when
I thought that I was done.
I would also like to thank Arron for giving me the idea for my experiment.
Finally I would like to thank Mr. Newkirk for giving me the opportunity
to do the project and come to SOAR in the first place.
Top of page
Menu of 2001-2002 Science Projects
Back to the Selah Homepage
|