The-Terminator

							            The Terminator
                EF152 Team Project

                     Team: E4

                    Section: E1

Colby Mattie, Eric McEwan, Carson Barnes, Adam Moon

                      4/23/09
Abstract


       The goal of this project was to solve an open-ended problem of powering a small

light bulb by harnessing wind power and converting it to mechanical energy and then

converting that energy to electrical energy. Our group had to research some basics of

electricity and come together to share ideas of what to build and how to build it. After

several meetings, concepts thrown out, and a few generators later, our group was able to

construct a nonconventional windmill that was able to harness the wind energy and

effectively power the light bulb.




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Introduction


       Professors Schleter and Bennet decided it would be fun to toss the EF152 classes

one last project before finals hit at the end of the semester. The project had a $40 budget

which you will later see in Table 1 that we barely met. Our windmill had to generate

enough electricity to light a small 1.5v, 40 milliamp light bulb. Dimension requirements

for the windmill were 0.5m x 0.5m x 0.8m. Finally, the wind power required for the

windmill would be supplied from a fan that would emit roughly 20mph winds. (Supplied

by the generous EF152 professors.)



Background



       For centuries the power of wind has been harnessed by man and converted into

mechanical energy. This form of mechanical energy was then used for many different

purposes such as grinding up flour or pumping water from a well for irrigation purposes.

The earliest windmills arose in Northern Europe around the 12th century. From there they

only evolved to become bigger and more efficient. The windmills of today are still used

for purposes originally built, but now they also include tasks such as producing electricity

for several peoples’ houses.



Design Process



       Windmill:




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       This process started out with the group collectively making freehand sketches of

possible designs and then as a team deciding what would work the best. After

deliberating possible ideas, we made one of many home depot runs to gather the

necessary materials. Our original design had a horizontal design with curved flaps to

catch the wind.

       After building a rough model of our windmill we noticed a couple of flaws in our

design. One hinder was that when our flaps spun horizontally they would also move back

and forth generating friction. We thought over our design one last time and decided to

rotate the windmill 90 degrees to an upright position. With this idea it still spun but

rotated on a point at the base rather than on two supports. This also helped spin the

magnets in the generator easier by not putting stress on the rod from the weight of the

magnets. After viewing the other windmills operate, it is clear that this was a major

benefactor in our design.

       Another problem we ran into was how our magnets spun inside of our coils. They

spun the wrong way in accordance to how the copper wire was wrapped. After adjusting

how the magnets spun we were then able to generate over 1.5 volts of electricity.



       Generator:



       The generator we used for our windmill used a small brass dowel rod with four

block ceramic magnets, four large round earth magnets, and four small earth magnets

attached to it. The magnets are inside a hollow cylinder with magnetic coated copper wire

wrapped around it about three hundred times with both ends sticking out for the positive




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and negative ends. When spun by the windmill, the rod with the magnets attached

creates a current witch produces electricity.

         When building the generator we encountered into many problems. The first

design was to spin the magnets in the wire. The first generator had the magnets spinning

but we had the wire wrapped the wrong way and were not breaking any of the magnetic

fields and not producing a current.

         After that, we tried spinning the wire inside the magnets. We had a metal cylinder

with our magnets attached to the outside of the cylinder. We had the wire wrapped

around the rod so it would spin inside of the magnetic field. We then had our positive

and negative ends brushing against two separate copper tubes and had wires from the two

copper tubes to the light bulb. The problem with that idea was that it was too hard to

make sure that the copper wire would constantly touch the copper tubes and they would

fold and not touch the tube. After figuring out that we had our wire wrapped the wrong

way we went back to the first design and wrapped it right and could then product the

energy to light the bulb.



         Table 1: Bill of Materials

                   Product                                         Cost

Magnetic Wire                                       $6.95

Magnets                                             $15.00

Brass Rod                                           $2.95

Scraps                                              $7.00

Glue                                                $4.95



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Tax                      $2.85

Total                    $39.70




Design Description

                                 Generator is located at bottom of the
                                 design with magnets attached to the
                                 spinning brass rod.

                                 Magnets are spun inside of a
                                 Pringles can wrapped with roughly
                                 300 turns of copper wire.

                                 Windmill is supported by PVC pipe
                                 (supplied by the bins in Room 113
                                 of Estabrook) and wooden shafts.




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Analysis of Efficiency

Volts: 1.8              Amps: 0.04

ρair: 1.225 kg/m3       Area = 0.03613m2

Velocity = 20 mph = 8.94 m/s

Ptheoretical = ½ * V3 * Area * ρair
                  ½ * (8.94)3 * (0.03613m2) * (1.225 kg/m3)
                  15.81 Watts

Pactual = Amps * Volts
           (0.04) * (1.8)
            0.072 Watts

%Efficiency = (Pactual/Ptheoretical) x 100 =(0.072Watts/15.81 Watts) x 100 = 0.455%

Conclusion

        Even though our windmill’s efficiency was extremely low, we were able to meet

the requirement of lighting the small light bulb. Our motto during the project was: “if

more power is needed, run to Home Deport of Radio Shack for more magnets.” The

power of all the magnets combined coupled with the high wind speed turning our shaft at

a very high velocity was ample enough to produce the power required.

        If we were given the option to redo our windmill, we would use more time in

researching how to harness more power like the one group that discussed flux. Our

windmill’s low efficiency is most likely due to not breaking enough flux lines to move a

strong electrical current to the light bulb.




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                                   References

http://www.windmillworld.com/windmills/history.htm

Recitation 5.1, Patrick Berge and Professor Bennett




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