This is an idea that has been around for quite a long time.
Curbina - maybe a good application for a compact suction air-powered Tesla Turbine, to drive the generator.
A wind turbine that sucks (in a good way)
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This looks like a variation on an idea of channeling faster moving air from up above down to ground level to grab the extra power available up there. It won't work, because static pressure decreases with elevation, and Bernoulli's Equation, which governs the whole business, involves static pressure. You would lose some or all of that precious power difference to overcome the increase in static pressure. Wind mills operate on very small pressure differencials.
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It won't work
Here is a 100kw version that was built in the 1950s
http://www.eolienne-a-depression.fr/images/stories/documents/Enfield_Wind_Power_Exhibition.pdf
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Mildly off-topic. Apologies.
Just yesterday I was discussing the current generation of wind-turbines with my grandson, now a wind-turbine service engineer. They use more heroic gearing-up to feed the alternators than I imagined, around 11:1.
When it comes to servicing the new ones, life is pretty easy, just a few bearings to grease, and oil-levels to check. They also check for metal-particles in the gearbox oil - a sign of something about to go wrong. They also park the blades and test the traversing gear, this keeps the blades facing into the wind. So he starts work at 8, and is usually home by 3.30. But the older ones (10 years+) are now a bag of trouble, and according to him the service engineers who work on the older fleets are 'worked like dogs'. He's looking to transfer offshore next year, because the pay is double and food and lodging on the service ships is free. 21 days on, 14 days off is another benefit, a work schedule he would appreciate, being young and single .
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I worked for a company that had become involved in designing and building wind turbine gearboxes in the 1980s. It very near bankrupted them. It turned out the the turbine builder had no real idea of the full dynamic duty cycle, and had completely underspecified the levels of shock and vibration. On instrumenting one unit, the gearbox company discovered that the peak oscillation input loads, induced by the blades passing the tower, were over 10 times those specified by the turbine builder. The company promptly pulled out of all wind turbine work, to save its skin.
Over the following decades, numerous gear manufacturers, right across the world, were driven into bankruptcy through their experiences with wind turbines.
In latter years, a division of the same company decided to re-enter the market – picking up work re-manufacturing, re-engineering, and redesigning wind turbine gearboxes – hoping that they wouldn’t get bitten twice.
In the mean time, though, turbines have been growing in size and power. The bigger they get, the slower the hub speed, and as the power is higher the input torque becomes truly horrendous - and the step-up ratios get ever larger.
Luckily, as it was a different division, I didn’t have much to do with the newer wind turbine gearbox designs (only occasionally being consulted on odd tribological issues).
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only occasionally being consulted on odd tribological issues
Do you think any water in the gearbox oil can trigger those “odd tribological issues”? There’s a paper I shared in the forum some time ago where the researchers found transmutation only when used a glycerol aqueous based lubricant, they thought it might be LENR.
Anyway, thanks for bringing this interesting windmill design to my attention, I don’t know why it makes me think inmediately of the Coanda effect, which is not related directly but popped up in my mind the moment I saw this because it reminded me the Coanda solution for helicopters without a rear rotor, which is also a sort of hollow tube.
A Tesla turbine might indeed help lowering costs of this design even more.
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Do you think any water in the gearbox oil can trigger those “odd tribological issues”? There’s a paper I shared in the forum some time ago where the researchers found transmutation only when used a glycerol aqueous based lubricant, they thought it might be LENR.
I guess you mean this paper. I've just read it, and it is interesting - but...
Before classing the presence of zinc as an anomaly, I would want to inspect the whole test setup. Zinc is so common as a steel coating (nuts, bolts, screws, washers) that it can crop up in multiple places, and is often overlooked. (I remember once insisting on an audit of all the components in a unit, to make sure there was no zinc - as the additives in the lubricant being used would dissolve it. And it turned out that a couple of zinc plated bolts had slipped through the net, despite everyone insisting there would be none). In the test described in the paper, any zinc present would end up in solution if there was water in the lubricant, and so it could end up being redeposited on friction surfaces. This wouldn't be the case for the ordinary mineral oil.
I sometimes had to look at the sort of Oil Condition Monitoring reports that Alan Smith mentioned, and it was always tricky to figure out the origins of some of the elements. The complex gearboxes the lubricant came from had several thousand components - and reports with anything other than the usual wear products were often passed to me to see if I could guess their source. What I didn't tell them was that as well as hunting through the constituents of any alloys and polymers present, I also kept a eye out for possible transmutation products - as the particular lubricant in question was hydrophilic, and so there would be varying amounts of water present. However, although there were a few mysteries, over the years, I never found any consistent evidence.
A Tesla turbine might indeed help lowering costs of this design even more.
I suspect that matching the characteristics of the windmill rotor, centrifugal air pump, and power turbine, would be non-trivial - although it would be an interesting exercise. And power transmission via vacuum does have some obvious issues. For a start, the maximum pressure differential across the power turbine can't be any more than 14.7 psi - and, in practice, is generally going to be a lot less. That means that a relatively high mass flow rate of air will be needed to get anything like a decent amount of power out of the system. Whether that would be compatible with a Tesla turbine, I wouldn't know, without further study.
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This looks like a variation on an idea of channeling faster moving air from up above down to ground level to grab the extra power available up there. It won't work, because static pressure decreases with elevation, and Bernoulli's Equation, which governs the whole business, involves static pressure. You would lose some or all of that precious power difference to overcome the increase in static pressure. Wind mills operate on very small pressure differencials.
Oops! I was looking at this backwards. Sorry.
When you take energy from the air stream you slow it down. This scheme adds air to the airstream above which would slow it down, but with no direct energy production. The energy production comes from the difference in pressures between ground and above and the supposed centrifugal effect.
Having air spewing out from the blade tips will act to slow the wind turbine. Why? Because as I mentioned before a windmill is driven by the pressure difference between the front and back of the turbine. This arises because anything you put into the air stream retards the flow whether it's your body, an open umbrella, or a windmill. A force develops to drive the offender back, which means a pressure dome forms in front of the object as only the air is acting. Well, the pressure dome acts to slow and deflect the air flow. Some of the air flows around the object and speeds up. Faster moving air has lower pressure. As the sped up air flows past the back of the object a region of lower pressure forms. The addition of the air flow from the blade tips will upset this balance.
Ultimately, it seems to me this ends up being due to the pressure difference between ground and above. You would get as good or better results by replacing the turbine by an umbrella shape or a tear drop shape with strategic placement of air introduction to the flow. Ultimately, conservation of energy applies. The energy you get out reduces the energy in the air stream by the same amount.
For those of you interested in windmills I suggest you take a look at Betz's derivation of his limit. What was his mistake?
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Looks like this thread will slip into oblivion. Probably just as well. But before it goes I would like to say that it will likely work to some degree. I call this the fire hose method and it has issues with ramming all that air into the air flowing around the wind mill. Since these people are not likely to pay me a consulting fee for suggesting a better approach, I'll let it go. I will suggest, if they are determined to do this, they use smoke to see what the air is doing. It works. Cheers!😎
