Author Topic: High Solidity Darrius Type  (Read 2984 times)

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vawtman

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High Solidity Darrius Type
« on: November 03, 2006, 09:51:01 PM »
 I was considering converting to 4 blades now im thinkin maybe 5 or even 6 on the 8x8.Its been a lazy summer more time thiking than working.Cant believe how time flies.


 Each blade=24in chord  8ft high

            5.5 width

 Perimeter=25.12ft


 So 6 blades would cover almost half the perimeter.


 Should speed up well in low winds.


 The airfoil shape is in my files for anyone that didnt see it.


 The little 2x6

   2 blades same chord same shape, so 48in

  Perimeter=18.84

 This turbine has been through 60mph winds with a max of 120rpms.It seems to reach this speed around 30mph winds and hold its rpm constant after that, but the tower loading is impressive just ask a 41n bent wooden post.


 The moral of the story is with good solid construction and very high solidity,the turbine would reach a certain rpm and stay there.No overspeed worries and the stator could be designed to sustain this rpm.Set it and forget it has Ron Popeil states.


 I wonder if this would work for the hawts also, same blade design only many more.


 Thanks for your opinions

« Last Edit: November 03, 2006, 09:51:01 PM by (unknown) »

Darren73

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Re: High Solidity Darrius Type
« Reply #1 on: November 03, 2006, 03:12:09 PM »
hi Vawtman,

could you please sketch out the plan view of a blade showing the turning circle reletive to the blade profile and any key dimensions used.


many thanks

Darren

« Last Edit: November 03, 2006, 03:12:09 PM by Darren73 »

vawtman

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Re: High Solidity Darrius Type
« Reply #2 on: November 03, 2006, 03:59:03 PM »
Funny Darren you actually want me to do a technical drawing.This will be fun(wheres max t when you need him)

Did you see the airfoil shape if so imagine 6 of those spinning in a 8ft diameter.Do you want a top veiw.Side views get expensiveLOL


 Me try draw tomorrow.Gotta go to walmart and get new colors(kidding)

 Thanks this will be fun not sure if it will help.

 Not sure how to diagram the stall effect.

   V......

« Last Edit: November 03, 2006, 03:59:03 PM by vawtman »

Darren73

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Re: High Solidity Darrius Type
« Reply #3 on: November 03, 2006, 05:08:16 PM »
lol i did see your pictures of the airfoil, nice work, was looking to build a similar unit to yours, where I live I doubt my neighbours would be too happy at a hawt in my garden, they managed to get the proposed wind farm near us scrapped :-( typical i'm green as long as it isn't in my back yard types.


regards

Darren

« Last Edit: November 03, 2006, 05:08:16 PM by Darren73 »

vawtman

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Re: High Solidity Darrius Type
« Reply #4 on: November 03, 2006, 06:00:09 PM »
Your neighbors wont hear a peep from the turbine blades no matter how high the winds.

 Have fun and willing to help if needed Darren
« Last Edit: November 03, 2006, 06:00:09 PM by vawtman »

WXYZCIENCE

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Re: High Solidity Darrius Type
« Reply #5 on: November 03, 2006, 07:43:34 PM »
Vawtman, you got an audience that are all ears. Keep thinkin.


Joseph
« Last Edit: November 03, 2006, 07:43:34 PM by WXYZCIENCE »

vawtman

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Re: High Solidity Darrius Type
« Reply #6 on: November 04, 2006, 10:32:31 AM »
Darren the outer rings(2)will attach 2ft in on each blade thinkin 2in flat stock for that and the blades will 2ft flat stock running vertically(blade support)and welded to the outer rings.


 Should be an awesome low wind producer i think.

« Last Edit: November 04, 2006, 10:32:31 AM by vawtman »

Stonebrain

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Re: High Solidity Darrius Type
« Reply #7 on: November 04, 2006, 02:20:52 PM »
Hi vawtman,


I think some people said it is wrong for efficiency.

Forgot who said it nor when or where ,and anyway,

they can be wrong


keep on going


cheers,

stonebrain

« Last Edit: November 04, 2006, 02:20:52 PM by Stonebrain »

vawtman

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Re: High Solidity Darrius Type
« Reply #8 on: November 04, 2006, 03:27:14 PM »
Hello Stonebrain

 Ive been told several times that high solidity is a bad thing.Ive also been told that darrius types blow up many times.

 Not stopping me.


 Sure little skinny airfoils would be more efficient but would selfdestruct easily because of the rpms they could achieve.I dont want one like that spinning at 600rpms anywhere near me.Also i think they would be hard starters with limited torque in low winds.You could use many many little foils to obtain the same result has im seeking too much work in my opinion.


 Thanks V......:<)

« Last Edit: November 04, 2006, 03:27:14 PM by vawtman »