PM Generator progress

[FrankG]

Below is a link to the progress I've made on a PM motor/Gen and some very basic but important facts about calculating power I've learned...

http://www.theworkshop.ca/energy/Wind/4/wind4.htm

I realize that this stuff isn't rocket science, but regardless of how many times that you read about other folks progress nothing comes close to making the mistakes yourself...

At present I'm looking for some guidance on selecting and sizing blades for the unit in the link above... It will need to spin in the 600 to 700 RPM range to generate 10 to 20 Watts... Is it realistic to oversize the blades for use on the next revision gen after this one? Or is the sizing and speed related such that each unit is unique in it's requirements....

I don't want to get too hung-up on indepth math, but certainly don't want to waste time on poor concepts or practices of blade design either...

Is there such a thing as a basic shape, twist and taper that fits most applications and will be semi efficient???

I have started the learning curve on TSR, Chord etc... but have no reference so it does seem somewhat abstract at this point... (the OP blade design primer was down last time I checked...)

 Somehow I feel obligated to point out that my objective at this point is not to generate much power with these projects(obviously), but rather to learn how to generate power and scale as lessons are learned...

As always any assistance is appreciated...

[Nickola]

Frank, I was thinking about the expense of the propellers or the time consuming factor if making them yourself.  Take a bicycle rear wheel off a medium mountain bike need a resonably wide wheel, take the sprockets off.  Screw a pulley to your wheel where the sprocket came off. Now cut some lengths of stormwater pipe about 2 foot wide, (60cm). Cut the 2 foot sections in half lengthwise this is quite easy on a bench saw. Keep your hands well away from the saw blade. You will need at least 8 of these C sections 10 or 12 may work better. Take the tyre of the wheel. Screw the C sections onto the bicycle wheel with self drilling screws, cap the ends of each piece of pipe. This should look a little like a darius wheel and operates the same way. Now make up a frame work with some thing sustancial like angle iron, tube steel etc. Mount your wheel on the frame and generator or alternator in the centre. The bearings will wear out after a while i suppose, this means replacing the wheel, but all other parts should be reuseable. I have tested the wheel with the downpipe by itself and it works fine, but have not tried the frame and generator yet.  The Darius Wheel is another idea. Just a thought or two . Good luck. Doug  

[steak2k1]

Very interesting projects you got on the go Frank.!  Nice site.

I am one of the urbanites (N. Calgary but used to live in Cornwall), you mentioned , and am also in the process of learning via building a small wind genny.  I might suggest you may wish to check out Hugh Piggots books if you don't already have them..??

I just got my books yesterday, and they are an excellent source of info on all aspects of wind gen fabrication/theory as well as actuall plans for a 8', 10' and a 4' axial flow PMA wind geeny.

Of course, the books arrived a fair bit after my build started...but tis OK, am now just working on carving the blades, likely do them this weekend.

Good luck and look forward to checking out your site and your progress.

rgds,

stk

[FrankG]

Doug,

Thanks for the darius idea, though I should have said in the original post that I want to use wood blades... likely hand carved, but possibly CNC milled, if nothing else then to set the stations as a guide for carving.

Steak2K1,

I trust that the "West" is agreeing with you... I heard that Ralph Klien is cutting cheques to Albertans, as a result of the Oil-dividend... While here in Ontario there is talk of more Nuclear Power Plants to be built...

I should just get Hugh Piggot's book...

[steak2k1]

Well, Ralph is a lame duck...and not exactly a visionary.  

Dalton McGinty is a LIAR & that = a Liberal...but I do give him Major Cr for stopping sharia law.  A tad scary that.!

As for Nukes...don't see the need other than to prop up the established utility/corporate structure.  Nothing but steady as she goes there eh.?...Politicians/Banks/Insurance Co's/Oil co's/Auto Co's.....all in the game and they never lose the $$$, just us, the "great unwashed masses".  I truly hope there is a peacefull revolution within the urban centres and we are able to break the back of that particular unholy alliance by everyone embracing RE and Major conservation.  Gee..starting to sound like an anarchist.

The bottom line is that anyone living the average 2 car 1500 sq ft home/attached garage/2 kids ... will never again be able to keep up to the increases in energy costs by salary/wage increases alone.  Period.

e-mail me and we'll talk about carving Cdn blades.!  (that would be those able to provide Low temp CVN of at least 45 ft/lbs @ -50C)   (-:

Rgds,

Stk