Physical Science Lab

[fleet130]

Yes!

[johnturt]

this is 1 of the hardest events my propeller really sucks any tips for studying and bulding a new propeller

[haven chuck]

Try making 6-7 blades out of balsa (of cardboard for a prototype) at a 60 degree or so slant, going to the edge of the CD. It isn't the best design for us, but it should give you a decent windmill.

[iYOA]

we has regionals 2 weeks ago
got 1st at this event

the most important thing is that ur propeller MUST be neat
if its neat it will succede
we also used balsa
it was 1/32 in thick

we didnt know when we showed up
but we were allowed to have 2 separate propellers for low and high speeds

would having more blades(around 6) be better for low speeds or high speeds

oh and if you want to get really competitive at this event and are using balsa wood, bake the wood first so it is lighter (and a little weaker)
but that is not too important.

[haven chuck]

You can also special order it online so it is like 1/8 of the normal weight. Also, try to sand down your CD (on the top only), to make it lose weight.

[fleet130]

any tips for studying and bulding a new propeller

There's a lot of detailed information on the internet about homebuilt wind turbines. Start by writing down any questions you have.

Some possible questions:

What is the best turbine diameter?
Should the blades be wide or narrow?
How many blades are best?
What should be the angle (pitch) of the blades?
Does airspeed have an effect on the design?

Write down other questions that come up as you do your research.

Next, Google "Wind Turbine" and read the sites it lists. When reading those sites look for other appropriate terms or phrases and Google them also. Even if the first site you find looks good (or even GREAT) don't stop there. Different sites may have different ideas or may ignite a spark of ingenuity.

Make a list of the requirements spelled out in the rules.

Don't try to make the final product on first the attempt. Brainstorm different designs that comply with the rules.

If you're not sure about something, make a simple prototype/mock-up to test that particular factor. The prototype doesn't have to be fully functional or even comply with the rules. Its only purpose is to prove the concept will/will not work. Prototypes can be modified as many times as necessary until you discover the best design. This can be used to find construction methods as well.

After you've worked out all the bugs, build a finished product. Don't be surprised if more problems crop up while you're building it. Figure out how to fix them and continue on. Some problems may require starting over again. Don't be surprised if this happens more than once.

Once you have a finished product that has been fully tested, take a break. Next decide if what you have is good enough (only you can make that decision). Time permitting, you may want to go back to the beginning and start over again to see if you can come up with a better design.

Beware of changing a finished device to improve it. If it doesn't work out, you can be left with nothing workable at the last minute. It may be better to build a completely new device if you have the resources.

[croman74]

First of all, you should make sure that it is a meter because i found that certain models can't pick up low speed wind from a meter away.

What part of the rules say that the fan is one meter away? I keep looking but I can't find this. My coach just put me on this event so I'm starting kinda late.

[croman74]

Here's a pretty good site I found: http://www.windpower.org/en/tour/design/index.htm Look around at the different links. It really helped me.

[jweil_buddha]

What voltages are people getting? I've been getting
High: 550 millivolts
Low: 390 millivolts

[jweil_buddha]

That might not be that good
I just realized that