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Russians make wind dam.. with elegance

by fredouil Fri Nov 16th, 2007 at 01:04:16 AM EST




The wind dam would be located over a gorge at Lake Ladoga in north-west Russia.

Beautiful isn't it.


Read the full story at http://www.bdonline.co.uk/story.asp?storycode=3098374

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That is nice, does it work with the wind in either direction?

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Fri Nov 16th, 2007 at 04:43:12 AM EST
cows all face the same direction in a field usually, right?

you see where i'm going with this?

kidding aside, this is visionary...

'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty

by melo (melometa4(at)gmail.com) on Fri Nov 16th, 2007 at 05:05:23 AM EST
[ Parent ]
How many Megawatts?
by IdiotSavant on Fri Nov 16th, 2007 at 07:15:07 AM EST
depends how many cows...duh...

:)

'The history of public debt is full of irony. It rarely follows our ideas of order and justice.' Thomas Piketty

by melo (melometa4(at)gmail.com) on Fri Nov 16th, 2007 at 07:42:47 AM EST
[ Parent ]
Chetwood Associates' sail-like `wind dam' lands on Lake Lagoda - Building Design
The spinnaker shape is similar to the mainsail of a yacht

They might be good at architecture... but they don't know anything about sailing. The spinnaker sail is ballon-like in shape whereas the mail sail works like the wing of a plane.

Rien n'est gratuit en ce bas monde. Tout s'expie, le bien comme le mal, se paie tot ou tard. Le bien c'est beaucoup plus cher, forcement. Celine

by UnEstranAvecVueSurMer (holopherne ahem gmail) on Fri Nov 16th, 2007 at 08:54:11 AM EST
The spinnaker sail is ballon-like in shape whereas the mail sail works like the wing of a plane.

By that, you mean shaking so violently that it seems almost certain to fall off?  Or is that a Delta-only thing?

Be nice to America. Or we'll bring democracy to your country.

by Drew J Jones (pedobear@pennstatefootball.com) on Fri Nov 16th, 2007 at 11:10:23 AM EST
[ Parent ]
... the spinnaker shape is like the spinnaker of a yacht?

How counter-intuitive.

Oh, wait ... I find it more likely that they don't know which one is the mainsail.

I've been accused of being a Marxist, yet while Harpo's my favourite, it's Groucho I'm always quoting. Odd, that.

by BruceMcF (agila61 at netscape dot net) on Fri Nov 16th, 2007 at 04:00:55 PM EST
[ Parent ]
That's what I meant... unless the word spinnaker can refer to something else than a sail...

Rien n'est gratuit en ce bas monde. Tout s'expie, le bien comme le mal, se paie tot ou tard. Le bien c'est beaucoup plus cher, forcement. Celine
by UnEstranAvecVueSurMer (holopherne ahem gmail) on Fri Nov 16th, 2007 at 11:13:58 PM EST
[ Parent ]
OK, we're agreed that spinnakers and mains'ls are two different cows facing the same direction, but what is this thing?  Sculpture?  Power Plant?  Vodka Dream?

"Life shrinks or expands in proportion to one's courage." - Ana´s Nin
by Crazy Horse on Fri Nov 16th, 2007 at 03:15:00 PM EST
I think it is somehow intended to increase the efficiency and while beautiful I do not really see how it is intended to work.

Commenter Godfrey makes some good points over at the bd site:

Chetwood Associates’ sail-like ‘wind dam’ lands on Lake Lagoda - Building Design

Godfrey 15 November, 2007

Looks nice but unfortunately the idea is completely flawed and demonstrates a total lack of understanding in fluid dynamics (amongst other areas of physics). 'Dams' work because of the difference in potential between one side and the other. In a water dam, the differential is the gravitational potential energy of the water on one side vs the other. The size of the dam is unimportant for electricity generation, only the difference in altitudes. The energy harnessed is the potential energy lost moving water from higher altitude to low altitude. A wind turbine of the type here is exactly like the ones in the fields. What this 'sail' intends to do is increase the wind velocity over the blades and hence generate more power. However, as with water turbines, the power generated comes from a loss of potential energy. Here the potential is pressure. There must be a higher total air pressure on the inlet side of the turbine than at the outlet otherwise the air wouldn't flow. Sails are not used to generate pressure differentials, they are intended to generate force. The pressure difference on either side of a yacht sail is not much. But bigger sails deilver more motive force than smaller, because the small pressure differential is over a larger area. All a bigger sail will do in this design is create bigger forces, not larger flows through the turbine. And by the way, turbines (which are NOT propellers) work because air 'escapes' around them, not in spite of the fact. Sorry to party poop, but there are very good reasons why this hasn't been done before.



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by A swedish kind of death on Fri Nov 16th, 2007 at 03:49:54 PM EST
[ Parent ]
Sails are not used to generate pressure differentials, they are intended to generate force.

I hate to stick my neck out in a field that I am only in the smallest way tangentially involved, but...sails are indeed used to generate pressure differentials. Counter intuitive to what people see, sails typically suck the boat forward.

It may be true though that a spinnaker is more toward the force directing mode since it is used when running before the wind, but that is not what the commenter said. Yet, even being right about that, the conclusion can be wrong...there would be difference in potentials where the turbine is driven.

The first concept that I had when I saw this was the small wind catching sails that we would place over the hatches on hot languid nights in the Caribbean. I'm betting on Russia on this one.

Never underestimate their intelligence, always underestimate their knowledge.

Frank Delaney ~ Ireland

by siegestate (siegestate or beyondwarispeace.com) on Fri Nov 16th, 2007 at 06:50:26 PM EST
[ Parent ]
they should never have brought in the sail analogy...

this looks like a water-type dam for a lighter fluid (air) where the ambition as with any dam for power -- a weir and mill, a megadam and turbines -- is to increase the psi at the point of capture by having a wide "bucket" to funnel water into the turbine.

mainsail of a yacht is a very different kettle of wind, using the aerofoil effect.

a spinny is a big bag of wind not using the aerofoil effect (downwind only), so somewhat similar, but it still doesn't collect air in order to drive it through a narrow opening at high velocity.  what this app is most like, imho, is the old trick of using a balloon to make a rude noise.

The difference between theory and practise in practise ...

by DeAnander (de_at_daclarke_dot_org) on Fri Nov 16th, 2007 at 07:02:25 PM EST
[ Parent ]
I think Godfreys point is that the created force from pressure differentials is the purpose of the design of a sail. On the contrary, on a dam you try to minimize the force acting on it while maximising the potential.

Fluid mechanics is a bit tricky and there might have been some good modeling I do not know about involved, but from the look of it, I would expect that structure to have more force acting on it (increased risk of damages to the structure) but not that much higher output. Imagine if you like a big wave (water being the fluid we are generally most acquainted with) hitting that thing. Supposing it holds, how much of the water will pour through the turbine and how much will spill on the sides?

Sweden's finest (and perhaps only) collaborative, leftist e-newspaper Synapze.se

by A swedish kind of death on Fri Nov 16th, 2007 at 08:09:44 PM EST
[ Parent ]
I want to see if it does what it was intended to do.  Then we can speculate on how it does it.

I can swear there ain't no heaven but I pray there ain't no hell. _ Blood Sweat & Tears
by Gringo (stargazing camel at aoldotcom) on Fri Nov 16th, 2007 at 10:45:14 PM EST
But what is it intended to do?

We have met the enemy, and he is us — Pogo
by Migeru (migeru at eurotrib dot com) on Mon Nov 19th, 2007 at 06:11:12 PM EST
[ Parent ]


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