Author Topic: H-Darreius wind turbines ( VAWT ) !  (Read 169023 times)

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topspeed

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #396 on: March 28, 2025, 12:56:26 AM »
New blades for 6th version are on the way.

They are:

1. 45% thinner foil than in 4th version.
2. 15% more capture area by widening the moment arm
3. 10% more capture area by lenghtening the blades
4. fully laminar flow wing
5. blade's aspect ratio is 20% greater than in the 5th blade
6. the connection to moment arm is aerodynamically 90% more efficient than previous contraption

Also I will make solid foundation to the tower...tower is now really solid.

Wish me luck !

 8)
These wind turbines must for that reason in a deeper sense be of a timeless beauty, so that they do not in three or four decades hence burden a later generation with a heavy task of removing angular skeletons.....

Ulrich Hütter

Aerodynamics is highly educated guessing, worked out to 5 decimals

topspeed

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #397 on: April 15, 2025, 03:17:43 AM »
I made experiments with white light styrofoam.

I you spread laminating epoxy on it and let it cure...it becomes sturdy as a rock...weighs a little more than styrofoam...but way more harder that I tought it would be.

Anyone tried it ?

I only need to glue plywood sheet on it and it is extremely strong.

Will it become weaker when in use for week, months, years...decades ?
These wind turbines must for that reason in a deeper sense be of a timeless beauty, so that they do not in three or four decades hence burden a later generation with a heavy task of removing angular skeletons.....

Ulrich Hütter

Aerodynamics is highly educated guessing, worked out to 5 decimals

mbouwer

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #398 on: April 15, 2025, 03:59:10 AM »
If you have covered the styrofoam bladeform with epoxy and fibreglass,
Why would you need to put another covering around it?


topspeed

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #399 on: April 15, 2025, 04:25:50 AM »
If you have covered the styrofoam bladeform with epoxy and fibreglass,
Why would you need to put another covering around it?

(Attachment Link)

I have a mixed structure on it...lighter styrofoam foils are in the tip.

I am aiming on a laminar flow on it.
These wind turbines must for that reason in a deeper sense be of a timeless beauty, so that they do not in three or four decades hence burden a later generation with a heavy task of removing angular skeletons.....

Ulrich Hütter

Aerodynamics is highly educated guessing, worked out to 5 decimals

MattM

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #400 on: April 15, 2025, 07:48:00 AM »
Sounds a lot like model plane building.  As long as the spar and leading edges hold up it should be interesting.  As tough as fiberglass is to our skin it is weak against leading edge abuse.  May have to touch it up once in awhile.  The only real concern I would have it sealing everything up from vapor penetration.  It needs to repel water while allowing it to breathe vapors out.

topspeed

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #401 on: April 16, 2025, 11:31:39 AM »
Sounds a lot like model plane building.  As long as the spar and leading edges hold up it should be interesting.  As tough as fiberglass is to our skin it is weak against leading edge abuse.  May have to touch it up once in awhile.  The only real concern I would have it sealing everything up from vapor penetration.  It needs to repel water while allowing it to breathe vapors out.

Yes it is a bit like model plane wing building. I also dream about building a real aeroplane. No one ever ( well maybe ) ever built a mostly wood wing in extreme laminar flow as an aim.
These wind turbines must for that reason in a deeper sense be of a timeless beauty, so that they do not in three or four decades hence burden a later generation with a heavy task of removing angular skeletons.....

Ulrich Hütter

Aerodynamics is highly educated guessing, worked out to 5 decimals

topspeed

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Re: H-Darreius wind turbines ( VAWT ) !
« Reply #402 on: April 29, 2025, 08:15:23 AM »
New blade has both sides covered of the main part....tips are still without the covering.  ;)

16266-0
« Last Edit: April 29, 2025, 08:31:41 AM by topspeed »
These wind turbines must for that reason in a deeper sense be of a timeless beauty, so that they do not in three or four decades hence burden a later generation with a heavy task of removing angular skeletons.....

Ulrich Hütter

Aerodynamics is highly educated guessing, worked out to 5 decimals