1835 Darwin Wind Turbines - The Answer To Wind Generation
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- čas přidán 29. 08. 2024
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I was starting to get a little pessimistic about using wind turbines for augmenting our off-grid power system. But your enthusiasm for practical investigation is infectious. Keep up the good work!
the way i think about it is both wind and solar have pros and cons and its about utilising those pros and cons. mono crystalline solar cells have a great ability to generate alot of electricity during day time less at night time, however its ability to control temperature is really low, with a battery it can sustain the standard of living we have now. wind has a decent ability to generate electricity, depending on elevation and windspeeds, however its ability to effect temperature and combustion reactions are its biggest effect. however we are still in the electrical gold rush and havent really utilized other forms of energy to its fullest potential yet. a good thing to think about is why batteries are the only form of consumer energy storage, well ig you have snap heat packs and tanks which youd consider storage of heat energy and wind energy, but doing research on that alone will prove that study of electrical storage is a strong factor in why we dont have storage in other forms. tbf making a wind energy device would simply require vacuum levels of insulation with fully controllable or "set for purpose" heat conductivity, something really hard to liquify at room temperatures like helium, a tank that can survive high enough psi, then a way to compress it and cool it enough to solidify it. not qualified just thinking off the top of my head
May have been interesting to measure the wind speed coming out of the bottom with the anemometer for comparison.
could be just Low speed and High Pressure
agree, its likely tripling the air speed.
Exactly what I was going to ask.
Yes this would be most interesting. I'm thinking the surface area of the wind catcher is about 4X... wind speed at the fan should be about X4. So much scope for improvement. Great experiment more please.
My thought also
Cool, like the extended baffles. Would love to see 'smoke' added to get a better idea of turbulence and air movement especially on the leeward side.
Good idea 💡 👍🇮🇪🙏🏻
An idea about improving the design, vortex generator. Spin the wind in the funnel and the fan will spin faster.
I was going to suggest the same things.
Great minds think alike and fools never differ.
Which are we? Experiments alone can determine.
@@bmobert well another fool to your list, cuz I was thinking the same thing. Putting some angled slats in the cone at the bottom would give you a Vortex effect.
Said this on one of his other darwin turbine videos
@oddjobbob yeah that's why I said put some little angled slats of metal attached to the inside of the cone down at the bottom. You would have no chance of causing any turbulence up higher just right before the wind generator fan. The only way to tell if this will really work is to try it one time, then we'll know
Spin in an air column gives the flow stability. It reduces the potential for turbulence to reduce efficiency. Given that only half of the airstream is pressurized and the other is actually under suction. I.e. the back side of the air collection assembly is dead air under a lower pressure. No moving Louvre to stop air from blowing up and out.
The introduction to Darwin Wind Turbines by Dr. Lecter is absolutely hypnotising. Thank you.
I was amazed this morning after seeing the news that the council have erected a Darwin style turbine on Skegness pier. It's good to see your experiments are expanding people's imaginations and will to construct and test things. Keep up the good work 👏
This would be amazing to test with older corn bins or on top of old silos. I see lots of them as I drive around beautiful rural Michigan. The outlet could be adapted to several varieties of fans or turbines. One challenge will be back pressure from the outlet. If you could form a convex lid below it, that may create a negative pressure to help pull the air through the Darwin section.
Wow. I never even thought about converting old silos into wind generators. I wonder if anyone's done it.
Great job! I am currently experimenting with a cylinder design with a spiral pathway on the inside (like a rifle barrel) to increase cyclonic rotation. The openings are also angled parallel to the spiral to direct the wind into the tube in the same direction.
If you're willing to share your files as you go, I'd be really interested, and I'll bet many others would be too!
I'm working on a version of this myself- and I'm going to try a flat version- making a wall and then funneling it to a central peak. Thanks for providing this concept on youtube!
I've been printing off my own "Darwin Wind Turbine" but I've found that over time it has slowly begun changing, sometimes in rather strange and unexpected ways, and now it resembles something more like a lamp.
Evolutionary!
😂😂😂
You could put a 90º bend on a swivel arrangement on the bottom so the opening always faces away from the wind, causing drag in one direction through the devices, should help a bit, and maybe have the internal walls twisted to also form a spiral to direct the wind and give you full coverage of the generator fan.
I think you might have a challenger for the wind wall if you use several of those piped to a central chamber venting up to mimic a termite mound you might get a more stable output from all of them also allowing you to use the rocket stove or any other heat source for a more active capture. Thank you for the video and infectious curiosity
I love the whole idea of this Darwin Wind Catcher and not just for generating electricity. I think these would do very well on a roof to exchange air inside a home or shed. You put one at one end forcing the air down inside, and one at the other end pulling the air out. I also am interested in this design for doing mechanical work, I think I might like to try making one of these to constantly rotate a compost tumbler at a VERY low speed by gearing down the output shaft.
Darwin's (E) original idea was to use it to grind chemicals for the Wedgwood pottery.
Would using the electricity from the bigger version be as efficient as a gearbox if not more so as you don't need to keep changing gears as the mindspeed veries?
middle eastern houses have used that principle for at least 1200 years and it works really well for air conditioning
@@Silent_Flight yeah wind speed would obviously vary, but that's why I'm only suggesting something passive like turning compost. But windmills have been used for things like sawing logs for a long time. If the wind blows slower your productivity slows down, that's all.
@@gordslater the wind towers that they have in the middle east are also connected to underground rivers, which is where the cool dry air comes from. They're not taking outside air and cooling it in their homes it's being cooled underground and the towers allow for a heat differential to take place.
@@gordslater and I'm sorry I should have been more specific I'm just talking about using the darwin for air exchange, not heating or cooling. The inside would be the same as the outside.
By creating a vortex, with fins, on the inner downwards wind the "drain" speed can be increased for a better venturi. Just by observing the drain of a fauset when spinning the water clock wise on the northern hemisphere, you drain the sink much faster. It is fun to watch your ideas👍
One of the ideas for increasing airflow through an exhaust window fan was to inset the fan inside the room by as much as the diameter of the fan to allow extra air to join the direct fan blast from around the edges of the fan’s frame. T’would be interesting to test this idea with your wind catcher by dropping the generator below the Venturi fan by as much as fan diameter without the proposed enclosing tube extension. The typical Venturi pressure/speed differential results are for a “closed” system, not one that allowed the addition of air.
Thanks for sharing, love the channel! Just a thought that popped into my head while watching this is to reverse the direction and have the turbine on the top. The reason is that hot air goes up so naturally. So there will be less resistance on hot days 🤗 you could also deliberately make a higher stack, paint it black to encourage natural air flow with no wind blowing 🤔
Hi again Robert. Just love your videos. I have a suggestion. make your tower our of clear plastic with the wind going in and upward. in the sun the air will be warmed as it moves up the tower causing the air to expand and increase the air pressure. top it with a Tesla turbine attached to a generator.. this should increase the power genertated. Love your designs.
Really, really liking this idea! What I’m loving is the potential scalability on a more or less flat plane, I’ve got nowhere safe to install large moving blades, but a bank of these connected to a tree of guttering pipe could add up to a decent wind surface area equivalent to e.g. 2.5 meter blades, concentrating on a remote turbine. Maybe inside the pipe you’d need something like a cone (i.e. ‘air diode’) to prevent back flow out of the other Darwins.
Venturi
Always a very entertaining and exciting topic to play with, and you're a fantastic communicator.
I’ve used an AC PC fan (aka server rack fan) as a generator to test airflow designs, it actually worked quite well to tease out small improvements in efficiency. I was designing a seemingly simple side by side dual PC fan to 6 inch hose adapter but the airflow from the fans was interfering with each other and ultimately needed a barrier between them so the airflow was directed towards the hose outlet. I would have benefited from proper 3D airflow simulation software which I attempted to set up so that I could test a bunch of designs first before printing them so I could narrow down the best ideas without using so much filament and time in the design phase... unfortunately I wasn’t able to completely figure out the particle physics and outputting the final data and animation from Blender but I got to the point where I could visualize the difference in airflow between the models, but not a simulation of the actual fans, which unfortunately was the detail that I needed to study... I bet there are some open source tools for doing this out of the box at this point, it would be a great way to preview the differences of novel designs and help people modify existing designs by visualizing the airflow which can help when coming up with ‘shape’ ideas.
If you scale this up, have a look at the grain bins we use on the Canadian prairies for possible retrofit or design ideas. I’m very intrigued by this design. I think you have something here.
Later iterations of this would likely need an overflow valve. If the wind becomes too strong, having a means to prevent damage to the turbine section would definitely be worthwhile.
What about a large-diameter Tesla valve pointing against the incoming flow? At high wind speeds, this would act as a no-moving-parts check valve.
The large-ish diameter would mean that low and modest wind speeds could travel through "the wrong way" through the valve relatively unhindered. At high speeds though, the resistance to flow rises with the faster flow upstream through the valve. In very small capillary Tesla valves, resistance to flow in the wrong direction can be ~100x the resistance to flow the "right" way.
The trick with this idea is that you'd have to size the Tesla valve appropriately so that it provides air braking at the right air speeds. This would probably have to be trial and error to get it right unless you've got some physics major on your side!
I wonder if overall flow could be increased by having a block with several parallel Tesla valves?
@@mookiemorjax Thanks for that great idea. I was also looking for a passive way to control the flow speed. In any case I would put the flow control on the outflow instead the inflow, because it has smaller dimensions.
This is absolutely amazing … I’m really inspired by this idea
Your Darwin model looks great Robert and you discuss using 35 degrees arbitrarily . My first thoughts on watching this is that the slats , besides being at 35 should also be spiralling down like a multi start thread and there should be an internal tapered section , starting above the slats to assist the cyclonic air movement . This internal taper should prevent the nagative air pressure build up on the opposite side from which the wind is blowing and may even create a venturi effect resulting in an increase in the wind speed. I enjoy watching your output.
Really fascinating design here, thanks for sharing. It occurs to me that the spacing of the fins could be quite important, since of course if the fins are too close together, they'll create air resistance, like how an olympic swimmer gets more thrust out of their hands with the fingers slightly apart than all the way closed, the gaps are small enough that effectively it's still one solid flipper (hand). So the same effect could be at play with the fins. Maybe staggering them one more in, next more out, back to more in, etc could help offset that? Have fun, love your videos.
I think the fan being closer is better to give more torque to the fan. Would be interesting to see what happens if placed on the gutter of a house directing the wind downwards over the roof but using baffles to direct more wind to the fan is brilliant.
I feel like you should call this device a Wind Fresnel, Wind Lens, .....or Mini-Blind turbine. ;P You've actually piqued my interest in these as I'm really considering making a solar pergola and surrounding the support posts with this would look decently fashionable and make energy as well.
I'd vote for the term Wind concentrator. To generically define a whole range of ideas that turn a large area of slower moving air into a smaller area of faster moving air.
Then to refer to this kind specifically, we would call it the Darwin wind concentrator.
One might think of this as related to ducted turbines but ducting can have a large funnel in front compressing air going, or may have a large funnel on the rear creating a low pressure area that pulls air through.
the roof of one of these covered with solar panel sure wouldn't hurt.
many places a structure under 100 sq/ft needs no permit, and doesn't say a dang thing about it not being 15-20 foot tall. set your posts and build the unit to slide up them and lock in place?
Aye! You are right, reminds me somewhat of the wave power turbines that build a big concrete funnel above the water with a turbine at the top of the funnel where the wind will push through as the water rises.
That is a genius way to evolve the idea! Just expand the central reservation for some seating and performances and have the wind make the power around you. Nice.
Why not a series of Venturi planes that would accelerate wind speed hitting it? Just asking
That is great Robert. Couple of thoughts I think may be worthy of consideration:
1/ could the opposite side be generating a negative pressure and therefore sucking some air from the PC Fan? If so some very light flap valves placed on the bottom of each octet will stem this effect.
2/ I think the fan (generator) should be as close as possible to the Darwin redirector. Its much easier to limit losses in wires (bigger wires) than in a tube I would think.
i think this would be a really cool as a progression of the the wind wall as a kind of fencing, potentially with a vertical axis wind turbine mounted horizontally in the bottom mostly just to reduce the amount of electronics necessary and could possibly make it easily modular for longer fencing
The reason the fan that is not attached to the Darwin device is because the air is blowing around it. If you put a 4-inch or 6-inch pipe on that and then blew your blower into it it would produce. What makes the Darwin device a good deal or something that is worth researching and investing is the fact that it catches a large amount of wind and focuses it in a small area.
Keep doing what you're doing thank you.
Thank you for sharing Robert.
My windmill is the best design ever, its a cubic frame holding a vertical axle in the middle, 4 panel attached to the axle that the wind pushes around, each side of the frame has half a panel to shelter the wind from the negative side, a ring is half way up the frame with copper vire coil and a magnet held at the end of each spinning panel, as it spins it creates electricity, when the wind blows it goes so fast that is scary, but because of the centrifugal force it dose not move.
You can almost get away with pallet wood only and also the center can be used as a funnel up top and piped through one of the center walls out of the side to a rain water collector. The air exhausted from the turbine can also be useful for an ancient air conditioner system but modernized and piped through the three tunnel Dielectric AC. Which can also take advantage of the rain water collection for evaporative cooling.
I'm a fan of the added outer fins as it effectively increases the total area of wind being funneled into the collector. Just building the whole thing larger would likely have the same result, but with 3d printing at least, build size comes at a premium. Building as large as you can and then adding on separate fins in post production could go a long way towards increasing what kind of collection area you're working with.
As a suggestion for future progress, I'd love to see some thought put into the turbine side of the equation. It could even be a fun channel activity for subscribers to submit their designs to be tested against the stock fan as well as each other's creations.
Well done Mr Smith. You finally arrived at the Diffuser aka Assymetric Vortex. 👍👏
Love it! I wonder if you continued reducing the cone on the bottom, to 1/4 the size of the fan, then oriented the cone to one quadrant of the fan if it would increase the fan speed? The other 3/4 of the fan would likely need to be covered I reckon.
awesome
Ex turbine design engineer here. If you only load one quarter of the turbine you generate a rotor imbalance, create an unnecessary lever arm and could prematurely wear the bearings or just cause an instantaneous failure depending on the forces involved. Best to keep as equal a loading across the blades as possible
@@jamesmullen3827 Yessir that does make plenty of sense. Thanks for the feedback.
The only issue I see with one of these outside is wind driven rain. Which in Texas we get a lot of.
Rain being blown sideways would go into the piping potentially causing damage to the motor.
It wouldn’t be too much trouble to have the generator outside the tube connected with a belt or chain with the impeller on the inside of it on bearings so that the water need not soak the electrical portion of the device.
This is the best idea I have seen on this channel. Two thoughts: first, if you took off the fan temporarily, you could put the anemometer in the same location and measure the wind speed there to compare again that produced by the fan. Second, when you go to add a pipe, it would be great to have pipes of 1,2,3 foot lengths ( or 1, 2, 4 ) so you could measure wind speed and turbine output and get a rough idea of the shape of the curve of the loss of power. Can you put these on a 10 foot or 10 meter pipe and still get a high percentage of the power? Dying to find out.
Etrike up there too!
Your enthusiasm really gives me hope
I have an idea. If you used a hexagon and then made the path for the wind going down into a spiral, (but keeping each side of the hexagon isolated) then that would allow you to pre-spin the wind, and might be more efficient, because the wind would be faster on the outside edges where the fan is more effective. What do you think?
This is an idea that might work... not sure how much extra you would get, but I can say that professionally, we put "baffles" on the inside of duct work to prevent the wind sensor devices from artificially picking up more or less spin for vortex effects which obviously alters the measured wind speed. So, if the internal baffles direct the wind energy in the proper rotation... there should be some change. (not sure how much tho... I suspect it would only by a few percent difference).
Would you also get more drag from more surface area?
I am a novice, but your suggestion sounds like the centre funnel in my dyson upright cleaner. I saw a new clip last night on a CZcams channel named Ziroth. A new design for a propeller for drones and motor boats where the propeller is spiralled with a cut-out loop in each blade…
Hi, can I make a suggestion to make the construction cheaper and easier?
Think of a wine carton with the carboard separators which are just flat boards with perpendicular slots which form prismatic cells.
If you use sheet metal and make the slots at an angle so you form and angled mesh with an effective downward tilt angle of 35 degrees. I would also run the sheets at 45 degrees to the horizontal so the face of it looks like a diamond pattern (this should be a little stronger than running the sheets horizontally and vertically. Clear as mud?
You could also angle the grids slightly so they pre spin the air as @chris Bruner suggested in a previous post.
Just a thought... How about putting the anemometer in place of the fan generator to measure the increase in wind speed.
Then you could compare various designs of wind capture shapes, etc.
You should probably print a cone just over the center of the fan blade attached to the bottom of the pipe which will tighten the outlet and force the wind down faster. I say just inside the pipe at the bottom so that the fan doesn't carry anymore weight no matter how light.
You might want to try using a similar director on the under side to drive the air out of turbine creating a vacuum on the bottom blades of the turbine in the same way you use the top half to create a high pressure flow . This push pull effect may be more efficient.
You also might find that is always a limit to the area size of the director mechanism you can funnel air into such hole where the turbine sits.
This is a design that would certainly take off... Although it wouldn't actually lift off. You have a winner here. Love it.
Dang, I was hoping you were gonna show input windspeed and output speed using the anemometer. Very interested in seeing the windspeed increase percentage. Great video non the less!!
It seemed to be suggested that the increase in wind speed was proportional to the larger "swept area" of the tower vs the fan by itself.
I think the "freestanding" pc fan would work the same as the Darwin Turbine if you put the gray funnel piece on it, and held it in front of the wind source.
But you'd have to constantly turn it into the wind. A major goal in this is to passively catch wind from any direction.
Robert, I just had an epiphany with you 35 degree angle for wind directionality. I remember that there was a engineering modeling software program that was sold years ago. I do believe that somewhere I have a copy. This is old but I got it for free. All I have to do now is find the disks. Hopefully that will happen in a few days or a week. When found I will send you a burned copy for your enjoyment and educational learning. This modeling software is BANG ON which will help you get the correct angles the first time. This will save you a lot of time and frustration. Just hope I can find the disks. This will give you way more knowns from unknowns. Will let you know SIr.
Good luck with the Darwins wind turbine. vf
mine is at the point where I am just waiting for some wind to see how much wind makes it down the pipe, I have mine on the end of a 3m pipe, so that once I set it up i can bolt the pipe to my shed for support, then I will be able to start testing different turbines at the bottom
Fantastic, I've been watching the evolution of your various wind power designs for some time with great interest. The idea of having a wind capture device with no moving parts is brilliant. In Wales domestic conventional wind turbines need planning permission and there are all kinds of restrictions to install them. I can't think of any reason why even a full sized version would ever be an issue, even (possibly?) when installed on a roof (any suggestions anyone?).
Having spent many years in Nature conservation you may potentially have solved another issue. The full sized version might be a great home as a communal bat or swift colony!
Well, it does resemble a traditional weather monitoring "station"/ box with dimensions like an old manor dove cote you have a protected habitat...
Minced bat?
@@daveh6356 (oops, well I ass-u-med they meant a well ventilated structure, sans the fan... Lol)
Fascinating as always Rob, thanks! How about if make it out of metal and turn it upside down, so that turbine would be on the top then put a fire from the bottom? That will increase a lot the velocity of wind inside of the Darwin WT as power proportional to V3.
That could be like the rocket stove from Hell! Probably awesome for making adobe bricks!
If you put a longer tube on the downpipe then make the output hole about 1" it will compress the air and force the air to move faster. Then focus output air on just the blades of the fan. This air will be more energy dense and spin the computer fan faster. Also the longer downpipe will give it more back pressure
I love watching the iteration of a design into a functional prototype.
I really like the design Rob! Here is an observation to consider. Try leaving a gap between the cone and the turbine blades. It would draw air in to add to it's output through the gap. For example take a plastic bag and hold to your mouth and blow the bag up. Now give a gap between your mouth and the bag and blow. It will fill up the bag much faster that way. Maybe it will work with your design as well. Just a thought. Thanks for the video, I really appreciate it!
Design/print the inside of the funnel to have guide vanes, to start the vortex, before it hits the fan. Further, try a swivelled venturi exhaust pipe, pointing down wind, (to create a small vacuum). Must admit, wished I had such a workshop. Good luck. 😎
Sir, I do believe this wind harvester is the sort of wind energy we should be focusing on. I hope to have one for my own home one day!
Nice! Loving the continued r&d and progress of it!
This was very interesting, but the quote of the year is, 'I love it more dearly than my cat' 🤣😂
👍 Always tryin´catch the wind! 💨 Keep on! 😃
I really like your new design, simple, easy to build and no fancy curves. the next step is connecting the turbine to a Tesla turbine, maybe a Darwin turbine on the input of the Tesla and a Darwin turbine on the output, like a push pull effect.
Thanks Rob, very interesting! Cheers!
Tuning a system is always the fun part…have you seen the MIT toroidal fan blade design videos? They’re about reducing prop blade tip vortices and the associated drag…then you could play with reducing the backpressure behind the fan- or is it increase pressure in front of the fan? Laminar-turbulent-Reynolds number…ideas are spinning like prop blades no doubt!
And speaking of Venturi, what about printing an exhaust flare/cone/horn? The curve into and out of the generator may prove important to efficiency/output.
Great video again Rob!
Missed your videos last three weeks, trying to catch up with latest couple of projects and this one looks great! Cheers from London 👍🏴🇬🇧
@RobertMurraySmith >>> Just off the top of my head: Build two. One with the 'generator' directly attached to the bottom of the come. Build another with a length of pipe between the bottom of the cone and the generator.
Place both outside at the same time, and record the amount of energy produced by each one over the same span of time.
{I _PRESUME_ you thought of this already, but I figured I would comment anyway.}
I found your site deliberately looking for an aeromine type generator I could build. So I am following with a lot of interest! The top does have "moving parts", the panels that open. But I agree it should last a long time and can be repaired fairly easy.
Instead of vanes, you could have hundreds of helical cones in a petal pattern directing airflow onto specific points to maximise efficiency.
You could also have a mechanism 'storing up energy' and then spinning the unit as a whole to direct an immense amount of airflow from every cone all at once on to the turbine.
You should switch directions: Make it draft upwards and put a spinning pipe on top, like a weather vane. Just remember that it needs to expand the airflow again to be efficient.
Added benefit is that the turbine is further away from the ground and thus a lot less noisy.
Also, if there's a storm, this thing is likely not lifting off so easily.
I just had a thought about what might increase the efficiency of the PC Fan motor as generator a bit: Change the angle of attack on the vanes.
A fan's blades are the angle they are to efficiently push standing air forward. We need to match that angle, but in relation to the direction the air is coming FROM.
i have a auto siphon in my aquaponics greenhouse that spins the water into a left turning vortex so it will flow faster than straight flowing water.
Maybe add some fan blades in the tube beneath to spin it up into a vortex so the wind will accelerate even more :D
What about turning it upside down... like having the eventual covection force of the air helping the process (maybe a hot plate underneath, too - some black painted iron plate exposed to the sun, and/or a closed section (black painted iron ring) in the top - with a wind turbine at the top)?
... and using J shaped fins to 'invite' the air flow to rise from the moment it enters the wind (dream) catcher?
By the way, I just get to know this channel and I already love 'Sir Not Anthony Hopkins' ideas, witt and knowledge.
this is very similar to the wind catchers used for air conditioning in the middle east, which is seeing a resurgence in interest as people look for more economical and ecological approaches to new designs. it would be interesting to explore using a design like this for wind energy production as well as secondary functions such as heating a mass like the sand battery, and providing cooling in asimilar method as the middle eastern design.
Fantastic intro Rob! Maybe one day you can do one with an overhead camera where you're intensely working on something from your office chair with a long ash cigarette in mouth and you spin around in the chair and then the camera pans out in a spiral high into the atmosphere above the Thames like the Eastenders!
I do something similar, but use a flat-sheet rotar mounted at center onto a vertical shaft.
The structure twists the airflow and that big flat blade is immersed in that airflow and twists with tremendous torque.
I attach a d.c. generator of my own design and I have electricity whenever the wind blows from any direction with ONLY one moving part.
Love the series. I have been working with an AI on this theory. I come to find out a thing called 'critical velocity' exists. This is the principal that we are considering for the amount of force at the end of our "diverter pipe'. Key take away could be use 35' smooth pipe for lengthen.
8" pipe: Vc = 4.4 m/s
10" pipe: Vc = 5.5 m/s
17" pipe: Vc = 9.3 m/s
Now we can use the m/s against our blade/gen efficiencies.
To provide a more reliable answer, I would recommend using the following formula:
Vc = 0.634 * ((EI)/(rhoD*L))^(1/2)
where:
Vc is the critical wind speed
E is the modulus of elasticity of the material (for PVC, E = 3.0 x 10^9 Pa)
I is the moment of inertia of the cylinder cross section (for a circular cross section, I = pi*D^4/64)
rho is the density of the fluid (in kg/m^3)
D is the diameter of the cylinder (in m)
L is the length of the cylinder (in m)
side note to the collector device without improvements of flutes:
• Collector shape: octagon with a center cross that is 3 feet wide
• Collector surface area: approximately 13.5 square feet
• Collector: 40% of 13.2 sq ft (1.226 sq m)
• Collector material: polycarbonate plastic PVC
• Collector inlet/outlet diameter: 8 inches
• Height of vertical section of PVC pipe: 35 feet
• Diameter of vertical section of PVC pipe: 8 inches
• Wind speeds for calculation: 4 m/s and 6 m/s
• Shear strength of standard 8-inch PVC pipe: 2000 PSI
Based on our calculations, the estimated output
with 4 m/s wind speed is approximately 109 watts.
with 6 m/s wind speed, the estimated output is approximately 247 watts.
I would expect directing the wind upwards, into a "chimney" would make a big improvement. The external wind passing over the top of a vertical column, adds extra flow.
There may be a venturi effect at the bottom of the downward column, but the wind will be disturbed by the legs, and will be slower than the uninterrupted flow of the wind over the top.
the volume of air in the tower is pushed through the cone which compresses the air which increases wind speed which moves the fan. Under the fan is a low pressure area which helps to draw the air through the fan. I notice that the tower has a cap on it. Wondering if removing that would improve air flow as well because without it the downward movement of the air could draw in air from above as well.
As of February 20th the BBC is reporting that Skegness pier and a factory in Spalding have been fitted with 2m tall vertical wind turbines of this design in a trial. They are using the design which uses a turbine at the top. Will be intresting to see how they get on.
One thing that pops into my head is to ensure that the exhaust air flow mustn’t be impeded in anyway way … following that thought could we somehow cause a drop in pressure at the exhaust area of the fan to increase the airflow using some sort of static system…. There are so many great things you can do to take this further. Very exciting
I would expect drag analysis would help improve the performance of the wind collector. This is not the strucrure that Darwin designed though. I call this the Murray-Smith Aeromine.
I was thinking that without the blades like you said and having them as short blades on the internal funnel wall!
Robert, two hemispheres on the same centerline with your fan/generator between and what ever ducting connecting them, I prefer a bellmouth inlet and outlet, to connect the underside of one hemisphere to the top side of the other. Your Darwin creates a pressure differential been the inlet and outlet at the cost of two 90 degree turns and the sectioning of all those louvers. As long as the centerline of the two hemispheres is at 90 degrees to the wind, vertical orientation, then the pressure difference is produced while those large inefficiencies are avoided at the cost of more modest ones.
It may be better to turn it upside down; the table may be acting as a bit of back-pressure for the fan (unless you make the legs long enough). Also, if it's upside down, you don't even need legs.
I still laugh with joy, every time Robert teaches me something.
This is a great idea Rob.. Better than those big floppy blades turning around...Keep it simple!!!
I've seen your work recently, I'm really enjoying it, it's hard to find honest channels and straight to the point. Congratulations for the videos that are great. I want to try to learn a little with you, with your projects, I want to know if it is possible to share the files with us or if there is a website that I can download? Thanks!!!
Love your enthusiasm Bob 🥳 Great project 😊 xo 💕
Nice idea. I would suggest that it may be difficult to scale up effectively unless your louvres are hinged to avoid the effects of suction that will apply to the rear face in a real wind application.
absolutely inspiring nice job.
As an idea, paint your basic Finn structure black reverse the angle, 35° upwards. Pipe up several feet all in black your turban on top exhaust on top. That way you get expansion of the air you take in because of heating during the day anyway so you increase your air flow through thermodynamics just a thought I don’t know if it will increase enough to warrant the changes, but it be a nice experiment.
have you thought of making it black to absorb heat, designing it to capture the hot rising air?
I love the videos. I have subbed and just started watching them. I was just giving a little thought to the forcing the air down vs up; it would seem that forcing it down would mean there could be issues or concerns with water in inclement weather. Wouldn't the design cause it to also collect a lot of rain? Forcing the air upwards would use fins/vanes that would basically repel most moisture
There was a version from the 70's where the air was directed into a cyclone inside the tower which created a low pressure area pulling the air up through the turbine and out through the top of the tower. There was another one with no vents but water was sprayed into the interior of the tower cooling the air which would then blow out the turbine at the bottom (this one was designed to desalinate water, it just happened the calculations showed the production of excess power as well as desalinating the water but it did require piping seawater well into a desert).
Your vid is enjoyable and to see you having a good time doing it. That intake has many possible iteration. Imagine puting your vanes inside a structure like a hollow conch shell, I've seen the one you did like that. In shape of shell the wind movement can be controlled more reliably. In fact, if there's too much wind an iris can be employed
That smile at the beginning, killer!
It looks good too, I could see those on top of chimney stacks and would look pretty good!
Good Work Robert, keenly following 👍
The wind blows over our roof for pleasure and the sun shines bright on most days; this reducing the volume and weight of a small brown paper bag containing our daily kitchen waste (no plastics).
Every four days Or so, the dry wastes are burned. 😊😊I bow to the Sun and winds for these services😅😅😅.
Keep in mind as the wind goes around the structure it will crate a vacuum on the down wind side of the structure which will create a counter force on the motor reducing the potential power. Probably a lot less than the up wind side produces but it would still have some effect.
Another interesting experiment would be to use smoke to see what happens to the wind AFTER the fan. Optimising that dispersion (in the context of a wind that is blowing) would probably be needed in a real world example, where the wind blows not only at the top, but at the entire vertical column.
using the nozzle from the ID of the catcher down to the intake ID of the fan generator is choking the air which in effect slows it down, an idea would be to the make the catcher the same diameter as the fan intake and test both ideas, this would answer which is more efficient 'nozzle choked' or 'straight through'
worth the work to test this theory
Paul
I don't know if anyone has already suggested it. but old venetian blinds would be excellent ready-made slats. Curved like a plane wing should be better than flats. Very thin for less frontal drag, they would need good vertical support (vertical vanes)
If they were positioned in each frame with one end a bit higher than the other, it would give a cyclonic spin to the internal flow, as others have suggested. The vertical support vanes could be angled to enhance that.