The Coanda Effect (version 2013)
ฝัง
- เผยแพร่เมื่อ 19 ต.ค. 2024
- Text from this movie:
"So, one would expect the air to flow out of the fan horizontally in all directions,
but due to the Coanda effect; the air bends down, to almost 90 degrees
The airflow is being pushed down by the air above, because the pressure of the air in between the flow and the curved surface, is reduced by the suction of the airflow.
Next, an other example of the Coanda effect, where I used smoke to make the flow visible.
Air is being accelerated down, and part of the upper surface is in touch with reduced air pressure. This action gives the object a force up, thrust, that can lift the object.
Henri Coanda realized this, and then designed a flying disc based on this effect, in 1932!"
More about this at www.laesieworks...
On my site, I placed a copy of "The Coanda story" (interview, 1956). Great info:
www.laesieworks... - วิทยาศาสตร์และเทคโนโลยี
There isn't one single person commenting on this effect who can truly say that this behavior is "obvious". It is not obvious. This is a damn good exhibition of how some things in physics are counter-intuitive. Thank you for posting this demonstration!
It really is obvious
@@windowsxseven yep. and its even more obvious that it cant produce lift, either. any lift is simply reaction to accelerating air downwards.
figured it out when i was 8 or so, newspaper on an AC duct. oh my! magic!
took a few more years until i realised that the AC duct is BOLTED TO THE WALL.
bolt it to the newspaper itself?
it sits on the ground doing nothing. the atmosphere is pushing down on that layer of low pressure air as hard as ever...
what is really cool?
get a flat plate, poke a pinhole in the middle, attach compressed air.
use it as an air gun, blow stuff around. yay.
push it against a surface... air forms a thin, high speed layer, the low pressure high velocity "film" easily overpowering the impulse effects of the jet of air itself. and the surrounding atmosphere pushes on the back of the disc.
lol, i found that one out refilling LPG bottles and poking my finger over the vent hole... oooh, it blows but theres suction!
dont feel it with a simple nozzle, but add some AREA to it... something to squeeze the air BETWEEN...
by itself, what is the coanda effect "squeezing" against? more atmosphere that just keeps pumping down. it doesnt work.
but if you place something above it to work against, and anchor THAT...
lol, a "hovercraft monorail" that can suck itself to an elevated overhead roadway simply by blowing air AT IT...
the OP here wouldnt understand from the sounds of it!
ha ha, my best experience of "the coanda effect" i lost half my beard! brazing carbide tools, the pilot flame was playing up, using a lighter. put it on the bench... play oxytorch over work... with curved surfaces...
flame wrapped around a full 270 degrees and blew the lighter up in my face...
Henri Coanda was Romanian and after discovering this here called "Coanda effect" he designed a flying vehicle that was based on it. It looked just like a flying saucer. The schematics were stolen by German security and so the Germans came to build their disc shaped aircraft that the Americans confiscated after ww2. At the Romanian aeronautics museum there's a scale model of a disc shaped aircraft originally made by Coanda. Note that he never actually build a flying saucer. He was still designing them and building models when the plans were confiscated(as far as we know). And yes he also had the idea to increase the number of blades on a propeller and put that into a tube and from there he came up with the worlds first jet engine. Problem that he had encountered that he put that engine in front of the plane to replace the conventional propeller. That made the overheated exhaust gases to burn the plane not just in front but all way alongside it, and so discovering the "Coanda effect". He then tried to somehow invert it to push the gases away from the fuselage by adding winglike structures right behind the exhausts to direct the overheated gases away. .
please share some links to that flying saucer image !
I'm romanian and I'm proud! Coanda was one of the greatest minds of Romania!
Henri Coanda designed a plane in 1910 that some have claimed was the first jet aircraft. I seem to recall that that plane set itself on fire, (due to what is now known as the Coanda Effect) so it wasn't particularly successful.
He was romanian!!:)
radu gogoescu
He was indeed Romanian. And so was George (Gogu) Constantinescu, another brilliant inventor. Among other things he invented a means of firing through the propeller blades of WW1 aircraft that was used by the British in their famous SE5a fighter. It relied on a whole new branch of engineering invented by Constantinescu, and called by him "the theory of sonics." A very fertile brain indeed!
Tnx:)
Excellent demo!
Can't beat toilet paper science.
+Okto Putsch hahaha your comment made me shit myself
Evilshadowstorm Thank you, i also laughed my arse off, watching this !
+Okto Putsch One day at my junior high we went on a field trip they had done a sci. experiment and some people got that paper but he said it was really toilet paper xD
+BaaconHaawk when you drone I can only assume you a re referring to a multirotor..that be the case these two in no way relate, as a multirotor uses the same propulsion system as a helicopter (spinning rotors).
Except he's holding it the wrong way... The patent clearly shows the tissue comes over the top...
Thumbs up for Henri Coanda...the romanian who made this possible.
I'm proud to be romanian :')
Technically he did not make this possible, this has and always will be possible it is one of the laws of physics.
What he did is discovered why this happend, and what caused it to happen.
he also made the first jet engine powered plane in 1910
@@bursucu2912 Planes and flying saucers were already in existence long,long before. He just discovered it. Dis -covered (as in 'uncovered') what was covered.
@@martyrmessiah3903 call it whatever you want but thank him when you board the next plane 😂✈️
Good observation! The fan is NOT sucking air from below though. It is air swirling under the craft, swirling in a vortex ring shape actually, powered by the down going flow on the outside. Similar to how water can flow upstream at some locations near the sides of a river, or behind a rock in the river. Some fish make use of this to preserve energy (the trout is famous for doing that).
Henri Coanda a Romanian Inventor .Thank you for this video , and good luck in your new projects .
love the sound of something reving up to high RPMs!
Fantastic illustration
Toilet paper science is the best science XD
nachoij I used strips of toilet paper to map out the flow paths inside my PC case when I installed a beast of a new CPU cooler
Another consequence of this demonstration, is some poor person sat on the toilet realising the toilet roll isn't there
Low pressure produced by turbulence causes the change in direction. He also puts little rings around it to increase the turbulence, suggesting that he knows exactly how it "works".Turbulence is also why this does not produce much downward thrust.
Gotta admit, I hadn't prepared my eyeballs with enough water to remain peeled the entire "second example"! I also had to pry my hand from the armrest after lol! Awesome!
The Coandă effect is the tendency of a fluid jet to be attracted to a nearby surface.[1] The principle was named after Romanian aerodynamics pioneer Henri Coandă, who was the first to recognize the practical application of the phenomenon in aircraft development. wikipedia :)
Great demo...!
For all the flying saucer fans, you can levitate something if you just use a couple of these in the same way that drones use various propellers pointed vertically, not just one. It is too much trouble to try to control the huge unstability of a single centered flow, when you can have an easy-to control array of them.
the toilet paper demo is priceless (-:
Great report, Engineer First Class!
You know... I actually watched this video only because I knew that Henri Coanda was a Romanian :) But I had no idea about the flying disc design. Cool stuff!
The Coand effect and the vortex, are two of the many things I didn't learn at school.. !
Thank you! And I enjoy doing the experiments & sharing the results.
it is def. NOT the atmophere above it that pushes it down. if you flip this upside down, its still curving around the surface. look up "entrainment" (fluids) and put a solid object near the flow and you can start to see how it works.
Amazing!, briggs n straton has been useing it every since.
thank you for making these amazing lessons and videos!
I had never heard about this effect, thank you for posting. Something inside of me always knew that flying saucers are possible, but I could not figure out how. Thanks.
when exiting the fan the air goes out horizontally for lets say 60 degrees k? the solid surface the air meets because of the friction it slows down the air circuling let's say at 2or3 degrees. the air above the slowed one goes in the low pressure place caused by the slowed air creating a vortex wich meets the solid at greater angle the new air beeing slowed down even more .. so more pressured air comes from above so it could be more eficient than that we are used to
dumicris But you don't know what the saucers are made of. Maybe the material of saucer helps the flow of the air.
TheTechnoJunkee good one. Maybe the design of the material might help too, like the scales work for fish.
The atmospheric pressure will only be apparent whilst the object is stationary. Flying sadly would be out of the question.
even if there are flying drones using this effect? they look real.
An excellent and clear demonstration, thank you.
However, I just can't help but imagine poor Mrs Nijhuis sitting on the toilet going "Oh ffs Giesbert, the toilet paper again??"
Yes it is old stuff. That flying disc was designed by Henri Coanda in 1932. Not many people understand the Coand effect though. "not many" being an understatement.
To work with ions... is on my to do list. Long list. Time flies. And I'm still on the ground -not flying yet.
How have I never heard of this? Granted, I'm no physicist but this is kinda mind blowing. And it was demonstrated in 1932? I know what my evening TH-cam and Google search is going to look like.
This is REALLY cool. Have 2 of them spinning in opposite directions to cancel out the torque, there you go: you got thrust without spinning like a madman :D
Amazing just amazing.
Thank you so much for explaining this! I truly enjoy your experiments
Frankly I was hoping he was going to go ahead and let that t.p. get sucked in the intake and see how much of a mess it would make.
This sounds like a title for an epic action film.
Amazing video, thank you.
This is why, the world feels so mysterious.
It's really half of a venturi. The fast speeding air is lower pressure and adheres to the surface. It wouldn't make any difference what shape it is.
This one; up to 1.2 kg force that could lift. If you want more thrust for your energy; use a larger fan, a much larger fan.
Henri Coanda was born in 1886, in Bucharest, Romania , yep he was a Romanian inventor :) .
So ?
Top Job Thanks ; Stay Warm and Good Music...
I do many of my experiments with old stuff, saved from the trash. Most important is to keep high attention to safety, for these experiments can be dangerous.
"It's all fun and games until someone gets their eye poked out." --Famous quotes that all mothers say
Understood… I’m listening. Just want to point out… The finite stochastic fields based on particles trapped under pressure zones and the finite stochastic fields based on particles trapped by magnetic zones (which in both causes may cause multidimensional arrays within tensor probability considering asymmetrical forces) can interact differently when interlaced with ions and this may be nontrivial…
This nautilus design is common in pumps and compressors , it flings the fluid out of each opening with the center as the intake . The effect though in open air is interesting .
High velocity air means low pressure. So yeah this makes sense. Atmospheric pressure is greater than pressure of the air coming out.
It works, but far from an efficient means of developing downward thrust. That's why the same motor turning a ducted fan is the preferred choice today.
This would make a great fan. :)
Cool nice demo !
Nope, The air flows downward because of the dome shape below the output. As the air flows outward it must follow that shape, or a low pressure would be created around the dome.
big fan of your work, no pun intended :) this only works perpendicular to the horizon (because of atmospheric pressure)? wouldn't work if you rotated 90 degrees in any direction?
For those who don´t know , Henri Coandă was a Romanian inventor and aerodynamics pioneer.
How much lift does the contraption generate? Have you measured it, do you have any lift/rpm curves? Is that an airfoil-type blower?
Nice demo of Bernoulli's principle.
prodding around related videos they were all cooky then I come across this skeptical but brilliant video. Diamond in the rough ;)
a
reverse the machine and blow into the disc shape allowing thrust in 360 degrees. or combine two and guide the streams.
Pump protons into the core and add a superconducting electromagnetic field around it and certain light and sound frequency into the mix and wala.
i just love the engine sound
Yes I have seen that. Interesting, and similar to my ideas. Thanks for the tip.
I remember reading about the Coanda effect in Scientific American back in the sixties. Don't remember it being presented as being related to aviation though.
Friggin Awesome!
Muy Buen Video.
*¡¡¡ BUEN TRABAJO !!!*
Did you know there was an airship that used the same principle for thrust. Its really interesting.
Toilet paper aerodynamics right there!
in de year
helemaal geweldig :P
It did service in a workplace, to remove unhealthy fumes and such. It had a cover around it, snail shell type. It is great for experiments, but way to heavy for flight.
The Coanda effect is the principle that makes airplanes possible. Due to the shape of the wing the air above it is forced to move faster then it does below the ving. The faster airflow cause the pressure above the wing to drop due to the Coanda effect and the plane is basically sucked up in the air.
Allow me to offer a bit of correction: ;) The Coanda effect, in and of itself, does not produce lift. The Coanda effect merely keeps the air following the curved shape of the wing. What you're describing in your second sentence is *Bernoulli's principle* - the greater the speed of flow, the less pressure it exerts on a surface. You're right, the shape of the wing forces the air moving over the top to move faster than the air below it, but the lift is produced by the resulting *pressure differential* - high pressure underneath, low pressure on top. In other words, the higher pressure actually pushes the wing towards the lower pressure.
Cute experiment to explain friction of air and a surface.
great idea but to make it fly you should to support your version in bottom connected with the same motor and scale fan to bottom to quarter to make consented force for distributed to all body
the coanda effect exceptionally espectacular
The problem with circular, frisbee-type flying saucers was never getting thrust; the problem was, and is stability and steerability. Generating downward thrust is one thing, but good ways to go reliably, controllably, forward, backward, left, or right are hard to come by in a round craft. Even staying right-side-up is problematic; for gyroscope effects to work, the amount of mass and the radius you need means making the craft as a whole heavier and heavier.
This is cool, and clever people may indeed find a brilliant use for it at some point, but I doubt we'll be seeing 1950's-style flying saucers from it.
it's incredible you found out how helicopters work!
Excellent demonstration and a great video. I was wondering whether you get a laminar airflow over the curved surface via the coanda effect?
It is possible to make the coanda effect so powerful, that it can lift a craft, making it; a VTOL aircraft. Flying forwards fast though, will disturb the coanda effect's airflow.
GREAT VIDEOS! Okay so I'm an Owner of a company who works as a contractor for wind energy. I've been working in the industry for 10 years. And I'm a propulsion nut as well.
I looked at your website. Had you ever considered using high voltage ionization to assist with lift, also I believe a well planned placement of vortex generators would improve your wind flow by 2-3%.
Seem like a great progress over the years. Let me know if you have anything that I can assist you with.
Best Regards
That was pretty cool I like that a lot!
So...if you took the outer cone that the air is flowing past...put it on bearings to allow it to spin and added blades inside and out of it to it to apply lift...that would be pretty powerful
This is why when you pee standing up over the bowl some manages to hit the floor anyway. Science doesn't stop in the bathroom.
+ExtantF:--Whoa! When I pee it goes up! Then down--bowl or no bowl! Science does not begin in the bathroom either!!
Fascinating...
What is the efficiency of the 90 degree thrust when using as a propulsive force, leaving out the efficiency of the fan and assuming an equivalent 80% efficiency of the average propeller? Thus if I an getting 80% efficiency with a standard propeller (which is really not thrust but an air SCREW, what is the efficiency of this effect when used as forward, or 90 degrees from rotational plane, thrust of the "disc" you are using?
so cool
Yes; it was a hot day, and the wind from the experiment made it cooler. :-)
Dude, thanks for this video!
Unfortunately most of the people was fascinated about ...toilet paper! Imagine how interesting they are living every day!
I plan to build a larger scale version of this using a lawn mower engine at 4000 rpm, and a 4 ft. diameter disc. Wouldn't an increase in lift result from somehow improving CIRCULATION about an airfoil-shaped disc?
I *think* the McDonnell Douglas NOTAR helicopters used this for anti-torque control versus having a tail rotor.
I would suggest A:
Using simple,loosely hinged airfoils rotating around a central axis with an adjustable angle of attack and Coriolis Effect compensation. I think that these would be much more efficient.
And B;
I predict that,In a conventional aircraft,this type of device,used for forward propulsion,rotating on a vertical plane at 2700rpm will prove to be much more efficient and much more practical,even with a fixed angle of attack,when compared to Coanda type aircraft.
(P.S. Proposal "A" is over 70 years old an proposal "B" is over 100 years old,not mine.)
Hi Mike. I'm not sure what you have in mind, nor what you want to achieve with what you proposed. Many things can be combined. Go and try, is my suggestion. (and make video of it!)
Would you please kindly let me know what is the name of the impeller that you are using? I mean what should I be searching for if I wanna buy these types of impellers?
Thanks in advance :)
If the fan is reversed and its sucking in air, does the air going in still flow along the surface (upwards) or would it just come horizontally?
OK great. Now how can we weaponize this?
The Germans DID!
Every invention made in Romania was taken/send to Germany.
@@DanielCardei after ww2 russian took plans of austrian flying saucer from germans which then later appeared through a ceramics engineer in the weapon form..
I guess my simple question is what is the benefit of using this effect as thrust in relation to more standard forms of generating thrust. More efficient, control ability, compactness.....?
looks very interesting
Well then, never knew this before. Has is been proven to lift objects? The flying disc, is there a working model of it anywhere?
my boys are back in town, and i am indeed looking forward
Indeed looking forward? Looking forward to what? Komu není shůry dáno, v apatyce holt nekoupí. Ach jo ..
You are on the path to wonderful things, my friend. Been doing plenty of research of my own, but lack any funding. I also watched your curved vortex lift. I'd like to mention the possibility of the use of a non-tangible propeller/impeller though. I believe it possible to create a flying craft using a tesla coil wired in reverse to pull in free radiant energy. That could power a series of electromagnets to spin an impeller. This wouldn't work in space, but a nontangible torus equivalent would.
If you have the time look up a video titled -Phi Vortex Mathematics Torus Array-
It is 12 of the most eye opening minutes I have ever experienced.
This video really dissects the torus, and gives an almost eerie insight into the patterns between the numbers associated with binary code, the Fibonacci sequence, music, and the flow of energy.
The air does go out of the fan horizontally as you would expect but then, due to the proximity of the curved surface, it follows that and, because the surface curves downwards, the air goes downwards. This does not do anything that is surprising to a scientist (as well as many other people). It might have been novel before the second world war but it is just fluid dynamics - look at and understand the venturi effect and you will see why this is no surprise. I still like the toilet paper and, like a number of others, was hoping that he would have let it go into the impeller.
How did you make the smoke? I've been looking for some way to make some with house hold materials but I couldn't.
I don't know how I got here, but that was cool.
Henri Coanda... I would like to talk to him, about his engine without moving parts for example. Clearly ahead of his time. 1886-1972, and I'm from 1969. We could have met! -me in diapers.. On my site, I placed a copy of "The Coanda story" (interview). Great info.
Soo... we can use this if we could make a tower a big one, and build it in places where tornados are often a hazard?