| T O P I C R E V I E W |
| Snoopy |
Posted - 26/07/2007 : 18:54:42
Hi group,I want to have some green energy in my kennel. I've got the plans from Ben and I have a SA dynohub(don't know the age as there is no date on it),have some 110mm od brown PVC pipe ,some metal pipe and ali. sheet.I would like some help to decide what size and how many blades to use. I am going to make the new PVC blades, would three blades 450mm long be ok. What have other people had success with on the dynohub?
Snoopy. |
| 8 L A T E S T R E P L I E S (Newest First) |
| Victor |
Posted - 04/08/2007 : 15:21:38
Read more on the forum there is vast loads of information on small scale turbines. |
| Victor |
Posted - 04/08/2007 : 15:10:48
Hello Plaz.
Its an old Sturmey Archer Dynohub (without gears). They have a slight cogging effect ,but work very well producing around 0.5 amps which is useful to charge a car battery.
They work really well! They are good for beginners to learn from and are a good building block to advance onto bigger and more expesive projects.
There is many different types of off the shelf dynamos that are suitable for making wind turbines. The ones in the video show ben`s plans that make far more decent turbine blades in order for the Dynohub to spin faster and start quicker... THEY WORK BETTER THAN EXPECTED!!
I have a lot of videos on youtube but if you look at my website http://www.victor.me.uk you can see a few uploaded in there amoungst my other videos I have taken around where I live.
With the help of the Gotwind Forum everyone will be able to make their own Turbines at little cost!! Thats how I made mine!! I`m about to start a new one today so that I have two turbines up and running!! lol
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| Plaz |
Posted - 04/08/2007 : 04:25:05
Originally posted by Victor
quote:
Here is an old video from a few weeks back. The Turbine has been rebuilt and improved since this video was taken.Link below.
Nice video. Am I mistaken or does the nose of you turbine look a lot like the hub of a bicycle wheel?
Plaz
"Is that windmill done yet!?" |
| Snoopy |
Posted - 03/08/2007 : 19:32:32
Thanks Guys for the info.
Sorry for the delay in replying, been busy at work.
I have reduced the pvc blade template by 25% to give a blade length of 450mm. The 4" pipe i have is just over 900mm long so i can get 6 blades from it.As three blade do not seem enough i think i will make up four to start with like Victors, I can move up to five or six later if i have too.
Victor what length and what size pipe have you used for your blades?
Do shorter blades spin faster and does the Dynohub need to spin fast to produce the voltage.
Snoopy.
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| Victor |
Posted - 01/08/2007 : 23:50:36
ooh! I also find making the plate for inserting the hub into a square shape. It allows you to find the perfect centre for balance then make a round circle to cut out using something like a protractor. It gives you a hole in the middle of the square..... Make it out of nice non corosive material like decent wood or even better some type of UV resistant plastic board..
I think around 10 inches of a perfect circle would be the ideal thing to mount your dynobub into and it can have 4 blades screwed to it.
If you have small wind and your only hitting 6 volts ac it is possible to add a Voltage doubler to boost it to over 20 volts for decent charging in low winds......
Don`t worry!! lol youll complete your project here on the forum!! |
| Victor |
Posted - 01/08/2007 : 23:32:03
Hi Snoopy!
I`m more than willing to give you any help on your Dynohub Wind Turbine.
Personally I suggest making 4 blades for your Dynohub as it starts faster.I made my full turbine for under £30. A few days ago I put my turbine up even higher to around 25Ft off the ground. It does not want to stop turning!! It`s flying.
Here is an old video from a few weeks back. The Turbine has been rebuilt and improved since this video was taken.Link below.
http://www.youtube.com/watch?v=7K-DC-uMZyY&NR=1 1st effort
http://www.youtube.com/watch?v=k89QsE_M0Rk Vast improvement.
The plans ben has for the blades is excellent.If you can make 4 blades youll have a superb Turbine.
The Dynohub can trickle charge Car Batteries,but If you need more power look into better Generators.
At the moment my Dynohub Turbine rotates 90% of the day and probably most of the night too. |
| Rich |
Posted - 26/07/2007 : 22:31:35
Hi Snoopy! Welcome to the World of Wind!
I can only speak about the dynohub, but the blades shown in the plans look good. I chose to fit scaled down PVC blades on my wind generator. I scaled them down by a rough 25% and had to make them out of 4" tube as that was all that was available.
I think that you would get better torque from blades made from a larger diameter tube (ther is probably some complex maths to back up this hunch, but I can't face hunting for it ...). As for length, the power available to a wind turbine, at a fixed wind speed, is proportional to the diameter of the swept area of the blades. That is to say, for a given wind speed, the longer the better.
Of course, for any horizontal axis wind generaor the power developed is proportional to the CUBE of the wind speed - so I guess it all comes down to the wind really: the more the merrier 
Apologies for going on a bit. The bottom line is that you should build the wind generator to best fit what you have available. Don't fret too much over the finer details. Once it is up an running you have the perfect test bed to experiment 
Above all GOOD LUCK!
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| gotwind |
Posted - 26/07/2007 : 20:09:43
Hi Snoopy and welcome.
The date of the dynohub is usually stamped on the casing - It means very little really, I have a hub that is over 40 years old and still works perfectly - Things were built to last in those days.....
6" (150mm)+ diameter PVC pipe might be better, Victor has some good posts on this forum including images and Rich has attempted a 6 blade PVC propeller.
A 3-4 foot 6 blade pvc propeller may be the most promising for the SA dynohub.
The Futures Green - Getwind of it. |
