New VAWT's on the way?

[springgrove]

Check out this VAWT design waiting for patent approval.

http://www.tmawind.com/index.htm

http://thewatt.com/article938.html

Jerry

[RP]

This looks like the Sandia Savonius rotors with what Sandia called Augments.

[tecker]

My vawt project is on going .The idea of redirecting air flow to the downwind cycle while shielding out the upwind drag on a savonius rotor does make a big difference .

I like a moving foil with a tail better than a stationary foil . The pictures in the site are obviously taken of units in constant wind locations . They are all low to the ground . You don't need a large wind break to be effective at reducing drag on the upwind . Witch is what they explain .  

[electrondady1]

wish i had one !  

ilove the generator room underneath, looks like a big induction motor in there .

it's tough to see even when you zoom in.

around here there is a prevaileing wind from the west so it might not be necessary to have four augments.

it certanly looks strong.

i wonder what power that big boy makes

[motoman465]

Would I be assuming correctly that the different numbers listed for the airfoils are different designs?

Todd

[springgrove]

Looks like the numbers refer to the outer foils and also how the savonious is designed on the inside, 2 blades, 3 blades, shape of the blades, gap between the blades (at the center), no gap.....etc. etc..

Jerry

[tecker]

What's noticable on the half to three quarter overlap savonius is that the pressure free flows through the center . With and elogated parabola shape ( instead of a half cylinder )and an up wind break the pressure you normally hear woop wooping (trying to give a test point hear ) is gone you can hear air compressing but it's rushing like wind through the trees. I haven't had a constant wind low to the ground ( where my test rig is) for some time now but winter is much diferent here .

[vawtman]

Hi Jerry

 I beleive Ron posted a pic of a simular design awhile back.

 I cant seem to find any outputs to swept area of the rotor itself.

 Is this just one of those that pop up from time to time.Im wondering

[luckeydog]

Looks alot like my Grand fathers Vawt. it is 50 ft high and 6 ft wide. it is located in Lajunta colorado

[springgrove]

Wow Luckeydog,

Do you know how much power it produces?

Jerry

[springgrove]

When I got home from work I had some time so I decided to make a miniature of this design.  Not real fancy, about 4 inches wide and about 14 inches tall. For the rotor I used 2 pieces of 1 1/2 inch PVC cut in half and turned them into a "S" blade.  Joined in the middle (no gap), no rod running up through the middle.

The base was a 12 volt power supply fan that I had cut down to a small spinning disk that I could hook my meter to so I would have some idea of an increase in rpms.  The top and bottom of the rotor were 3/4 inch MDF disks.  The bottom disk I drilled about a 1 1/2 inch hole and placed that on top of the fan (acting as the bottom bearing).  The top I put a bearing in and was held by a brace.

Then I took my 3 foot by 3 foot box fan and turned it on.  Nothing happened as it is a single rotor so I gave it a little push to get it started.  The meter read about 35 milli amps.

I had cut 3 pieces of 1 foot by 2 foot 1/4 inch plywood.  Sitting on a stool, I kinda started placing the 3 pieces of plywood around the rotor like in the picture (boy I'm glad no body walked in, I probably looked like a real idiot), took some work only having two arms but I was able to do it.  The thing took off.... I thought it was going to fly apart!  As the rpm's started going up it started to vibrate badly, the meter read about 80 microamps, and it kept climing!  When it hit 100 it started to smooth out.  The max output came at about 139 microamps.  The only load was the meter, but that is one hell of an increase!

I think they have something here (I wonder if they got a patent yet).  I am going to make a better model and see what effect different style blades have.  Definitly need to improve start up.  Maybe a triple blade or an offset "S".

Anyway thought you might be interested.

Jerry

A wise man learns from his mistakes, a wiser man learns from the mistakes of others.

[springgrove]

Ooooops.

Said milli amps, then micro amps, meant milli volts dc.

Jerry

[luckeydog]

No Jerry i don't know it has been a while since the windmill has run but i do remember trying to stop it in a 35 to 45 mph wind and the disk breaks off a truck were used to stop it but that was not enough. and the break rotor had gotten extremely hot. it was a real power house.

[battle]

Here is the latest patent application that has been published.  Lots of good technical data in the drawings.  i can't actually believe they included this technical detail in the patent.

http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FP
TO%2Fsearch-bool.html&r=6&f=G&l=50&co1=AND&d=PG01&s1=%22Taylor%2C+Ronald%22&
amp;OS=%22Taylor,+Ronald%22&RS=%22Taylor,+Ronald%22

Or search

Patent application number 20060110243 at

http://www.uspto.gov/patft/index.html

Cheers,

Battle

[springgrove]

Hey Battle,

Thanks for the info, I printed everything out and went through it as I was on vacation this week.

These people are talking some huge output.

With a 12' X 24' rotor and a total height of 33', they claim 10KW.

With a 90' X 210' rotor and a total height of 230' they claim 1000KW.

They also say testing has shown that at high wind speeds, speeds that would result in a horizontal having to be shut down, are not a problem.  The patent app states this as being a big problem with horizontals, having to be shut down when the wind is at its highest output potential.

Jerry

A wise man learns from his mistakes, a wiser man learns from the mistakes of others.