The Wind Amplifier, The Venturi Wind Focus...

Around the world there are many locations that get steady but slow wind
from onshore and offshore breezes.

What no one has done as far as I have seen is find a simple way to amplify them.

I thought about this and the first thing that came to mind is one of the
features in a carburetor used in cars decades ago.

The Venturi effect.

My twist on this is to use 4 square sails near a windmill to pull the wind
into a smaller path across the blades of the turbine.

Basically imagine a vertical axis wind turbine with 4 square sails mounted to the
ground and positioned so that the most common influx of wind enters into the gap
created between the sails like a nozzle.

At my current location that would point the sails at the directions of the compass,
N,S,E,W and here is the real kicker.

Most ppl think that the power of a windmill doubles going from 10 mph wind
to 20 mph wind, it doesn't, its a cube of the power or EIGHT times the power.

Double Wind Speed equals 8 times the power

With a focus that provides 4 times the air speed, you get 64 times the power.

10 mph to 20 mph = 8 times, 20 to 40 mph = another 8 times.

This alone could solve electric power problems around the world for all time.

I turned this in to Google's 100 ideas to help the world, but it went ignored.

Let me know what you think !





[edit on 9-9-2009 by Ex_MislTech]

reply to post by Ex_MislTech


Cool stuff buddy

Sort of like...
When in town the high rises and buildings create "avenues" that focus the wind in one general direction and it's alot stronger than if you were standing out in a field in the same gust.

Good idea to harness this kind of effect

Amplifying the wind is not a new concept. There are several different DAWT (Diffuser Augmented Wind Turbine) designs that do (or try to do) just that. An inherent problem is all the extra "structure" required to hold the diffuser/venturi in the right place, and keep it turned into the wind, makes it very difficult for this type of design to compete, cost-wise. Plus, they simply don't work as well in real life as they do on paper.

The way you propose to do it however, sounds quite novel.

You misunderstand the Venturi effect. It does not amplify the energy of a fluid in motion.

When a fluid (including air) moves though a constricted section the velocity does increase. That is not the Venturi effect (it is part of the dynamics of fluid mechanics described by the Navier–Stokes equations). The Venturi effect is the reduction in pressure caused by the increase in velocity.

So yes, air moves faster through a constriction, but the force it would exert on the turbine blades would not be any greater because of the corresponding reduction in pressure. In order for the power to be cubed with the increase in velocity, the pressure must remain the same. In the constriction of the venturi tube, where the velocity is increased, it does not. Think of it as fewer air molecules pushing the blades.

[edit on 9/9/2009 by Phage]

reply to post by tjack

The DAWT concept is not based on "amplifying" the wind. The idea is to increase the efficiency of the turbine by reducing tip vortices from the blades.

reply to post by Phage

Maybe then I am referring to another effect, the increase in power is
real and can be felt between buildings in downtown areas.

The wind is focused and is at a higher speed due to the skyscrapers
channeling the wind into more narrow areas.

The best explanation I could think of was the Venturi effect.




[edit on 9-9-2009 by Ex_MislTech]

Originally posted by Phage
reply to post by tjack

 

The DAWT concept is not based on "amplifying" the wind. The idea is to increase the efficiency of the turbine by reducing tip vortices from the blades.

I think your confusing my idea with the DAWT method.

Mine does not stick a shroud on a turbine.

Mine is ground based, and channels wind that would otherwise
miss the turbine and put it across the blades, ie. redirect wind
and put it across the blades.

Some similar concepts, but the part that would redicret the wind
is larger than the turbine itself.

Again, it is like the wind speed increase that you feel in the downtown
areas standing amid the skyscrapers.





[edit on 9-9-2009 by Ex_MislTech]

reply to post by Ex_MislTech


Well yep that would work - after all any turbine can only generate energy from the air that is able to pass over it, you could have a bigger blade area or you could put it where the wind is focused to some level.

I'm not sure how much you would gain by artificially focusing it though - maybe just using geography? Or buildings?

Originally posted by Now_Then
reply to post by Ex_MislTech

 

I'm not sure how much you would gain by artificially focusing it though - maybe just using geography? Or buildings?

The power gain is specified by a cube in power for double the wind
speed, ie. if its boosts the wind up to double the speed you get
8 times the prior power.

A surface area that can redirect double the amount of CFM would get
around double the wind speed.

You can also see this effect when you open all the windows on the
wind impacting side of a house, and only one window on the opposite
side if there is a light breeze.

It is not 100% efficient of course, but it does increase the effective
wind speed out that one window.

reply to post by Ex_MislTech


No, I understand that your idea is different, I was just saying that the concept of getting more power out of a given speed of wind, "amplifying" it, so to speak, was not new.

See that little part where I mentioned the novelty of your approach?

Originally posted by tjack
reply to post by Ex_MislTech

 

No, I understand that your idea is different, I was just saying that the concept of getting more power out of a given speed of wind, "amplifying" it, so to speak, was not new.

See that little part where I mentioned the novelty of your approach?

Got ya, I was just letting ya know you get 8 times the power when
you double the speed.

Link to that is in the OP.

Originally posted by Ex_MislTech
The power gain is specified by a cube in power for double the wind
speed, ie. if its boosts the wind up to double the speed you get
8 times the prior power.

Well I think that's what phage was on about, you can double the air pressure by having the same amount of air pass through half the space - or you can have double the air speed but at half the pressure....

You can't have both because then you would be creating air from somewhere.

But yes I agree that you would get more power if you can channel more air over the blades... I suppose it boils down to how much you can increase the RPM of the turbine.... A higher wind speed with the lower pressure will still impart the same amount of energy as a lower pressure and a lower speed... If you get me, it's got to equal out

If you take a cross-sectional area of wind and reduce it's size to, say, half of what it was, you have decreased the area by a factor of 4. that means the wind will be moving 4 times as fast as it was when it entered the tunnel.

But it also means the wind energy is concentrated into an area one fourth the size it was. A turbine gets power from the blades, which would be one-fourth as big since the wind is one-fourth the size. So you have 4 times the energy and one-fourth the area to get it. 4/4=1.

Keep thinking, but this one won't work.

(Star for Phage for an excellent description of the problem and of the venturi effect.)

TheRedneck

reply to post by TheRedneck

I guess I did a poor job explaining it because none of you "get it".

I will do a small scale mock up model and post the results.

Pretty hard to argue with the results you can see in a video.

reply to post by Ex_MislTech

A test apparatus would be helpful, even if it's a proof-of-concept test.

Remember what Edison said: "Invention is 1% inspiration and 99% perspiration."

I'll be looking forward to your results.

TheRedneck

Originally posted by Ex_MislTech


I turned this in to Google's 100 ideas to help the world, but it went ignored.

I turned in a couple of my ideas and never heard anything. What ever happened to the Google program? Did anybody ever win? What exactly happened?

Originally posted by TheRedneck
If you take a cross-sectional area of wind and reduce it's size to, say, half of what it was, you have decreased the area by a factor of 4. that means the wind will be moving 4 times as fast as it was when it entered the tunnel.

But it also means the wind energy is concentrated into an area one fourth the size it was. A turbine gets power from the blades, which would be one-fourth as big since the wind is one-fourth the size. So you have 4 times the energy and one-fourth the area to get it. 4/4=1.

Keep thinking, but this one won't work.

(Star for Phage for an excellent description of the problem and of the venturi effect.)

TheRedneck

It looks like you and phage are wrong.

Here is the proof.

If you wanna stop by for dinner I will be serving crow.

As you might expect it will be all you can eat.



This really is old science and for ppl who like to talk like
they know all there is about science I am amazed you
two got this so terribly wrong.

At one time I lived in the third of three identical hi rises.
The overall shape was similar to the relationship of the wings of a tri wing fighter of WW1

When the wind hit the buildings at the right angle it created a a low pressure at the trailing edge of each building relative to the wind direction.
this suction amplified the wind immensly from the first building to the third

One would walk from the mild breeze in front of building one to the moderate breeze in front of building two, then in front of building three one would be butt sliding across the lawn helplessly caught up in a nassive vortex...

we found this great fun to watch from the balcony of my apt.
OP
I say pass

[edit on 12-7-2010 by Danbones]

reply to post by Ex_MislTech

Well now it makes sense to me. Yes, you are right. My problem was in visualizing what you were getting at. I guess my problem is that I sail boats and when I hear the word sail I think of it as an airfoil rather than as a scoop, which is what you meant. I visualized your setup as being a turbine surrounded with four vertical "wings". In this case the velocity of the air would increase over the wings but the pressure would decrease.

In the set up you really were talking about, the pressure and velocity actually do increase because the scoops are directing more air to the turbine.

I'll eat a bit of crow but...
It is not the Venturi effect or the Bernoulli effect. And I think it would take some mighty big scoops to double the wind speed arriving at the turbine. But yes it would spin the turbine faster.

I wonder why we don't see that system in use.

reply to post by Danbones


Very true Dan, I got the idea when I was at school and two doors opened
about the same time.

One on the down wind side of the school and the other on the opposite.

In that hall it created a wind tunnel because of the air pressure
built up against the side of the multi-story bldg just like you are
talking about.

So I tried making small windmills and then diverting the wind
with just a piece of plywood.

The windmill sped up a great deal.

Me posting that would just get the usual Ad hominem attacks
so here is a company moving forward with it large scale
for big bucks making tremendous power.

Never had the money to make this happen, but I am glad to see
it come about anyways.

This and jet stream power could provide all our power needs forever.