The Coanda Effect (version 2013)

[@tpowell453]

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!

[@windowsxseven]

It really is obvious

[@paradiselost9946]

@@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...

[@gigicaly]

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 At the Romanian aeronautics museum there's a scale model of a disc shaped aircraft originally made by Coanda.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. .

[@marka9261]

please share some links to that flying saucer image !

[@micultimy91]

I'm romanian and I'm proud! Coanda was one of the greatest minds of Romania!

[@universalsailor]

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.

[@29radux]

He was romanian!!:)

[@universalsailor]

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!

[@29radux]

Tnx:)

[@OktoPutsch]

Can't beat toilet paper science.

[@abggk2]

+Okto Putsch hahaha your comment made me shit myself

[@OktoPutsch]

Evilshadowstorm Thank you, i also laughed my arse off, watching this !

[@BaaconHaawk]

+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

[@AerialEscapade]

+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).

[@bosatsu76]

Except he's holding it the wrong way... The patent clearly shows the tissue comes over the top...

[@GiesbertNijhuis]

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).

[@danz409]

love the sound of something reving up to high RPMs!

[@chucktilbury]

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.

[@ariesk5n]

Thumbs up for Henri Coanda...the romanian who made this possible.

[@Babom_Official]

I'm proud to be romanian :')

[@rimfire806]

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.

[@bursucu2912]

he also made the first jet engine powered plane in 1910

[@martyrmessiah3903]

@@bursucu2912 Planes and flying saucers were already in existence long,long before. He just discovered it. Dis -covered (as in 'uncovered') what was covered.

[@donpablo8434]

@@martyrmessiah3903 call it whatever you want but thank him when you board the next plane 😂✈️

[@independentviews9245]

Excellent demo!

[@GiesbertNijhuis]

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.

[@nachoijp]

Toilet paper science is the best science XD

[@waynetemplar2183]

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

[@markrigneymd6570]

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.....?

[@GianfrancoFronzi]

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 .

[@TheTrumanZoo]

reverse the machine and blow into the disc shape allowing thrust in 360 degrees. or combine two and guide the streams.

[@annihilus10]

How much lift does the contraption generate? Have you measured it, do you have any lift/rpm curves? Is that an airfoil-type blower?

[@ryansta]

Another consequence of this demonstration, is some poor person sat on the toilet realising the toilet roll isn't there

[@brantbarker6264]

Pump protons into the core and add a superconducting electromagnetic field around it and certain light and sound frequency into the mix and wala.

[@johnlegere478]

Fantastic illustration

[@mattsimpson2367]

Can you please test a full sphere, and cone shapes too?

[@johnholzhey8149]

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.

[@annihilus10]

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?

[@whan6677]

Henri Coanda a Romanian Inventor .Thank you for this video , and good luck in your new projects .

[@thepretenda]

OK great. Now how can we weaponize this?

[@DanielCardei]

The Germans DID! Every invention made in Romania was taken/send to Germany.

[@cosmicyoke]

@@DanielCardei after ww2 russian took plans of austrian flying saucer from germans which then later appeared through a ceramics engineer in the weapon form..

[@GiesbertNijhuis]

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.

[@mrreymundo5383]

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.

[@Bl4azedOG20TM-kadar_lrt]

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?

[@royalcrestdrive]

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?

[@ElementofKindness]

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.

[@Osmone_Everony]

Doesn't the air stream loose much of it's energy due to this "bending"? Wouldn't it be more efficient if the air stream goes directly downward? I don't see the benefit of this technology.

[@muflatu]

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 :)

[@SomeoneCommenting]

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.

[@boredthump2]

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!

[@homoerot03]

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.

[@ehab3244]

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

[@bridgendesar]

What if you put a conventional propeller horizontally, would the same thing happen over a curve. Would there be any more lift then just pointing the propeller straight down?

[@HealthyDoubter]

Well then, never knew this before. Has is been proven to lift objects? The flying disc, is there a working model of it anywhere?

[@slevinshafel9395]

1:51 that look real SciFiction. The impulse can be utilized or its usless compared with helicopter ?

[@CristiVlacicu]

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!

[@morlanius]

Do you have any numbers for the relationship between rotation and air pressure?

[@GiesbertNijhuis]

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.

[@GiesbertNijhuis]

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!)

[@maxwelldynamics7495]

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?

[@nickgirard9018]

1:40 for awesome smoke visualization.

[@GOLEG11]

NOW! if you move this operational unit at a high speed of lets say 50mph, is it 99% aerodynamical? since it should push around the air-drag?

[@stagdragon3978]

I wonder if we could use this for cooling systems...

[@maysammirzakhalili4862]

Is it working in suction situation too ? In reverse ◀️ I mean? 🌹💖

[@SavageInsight]

Does the Coanda lifting effect have the same thrust/lift power as a helicopter blade of a similar size and speed with a similar power consumption?

[@joeestes8114]

Amazing!, briggs n straton has been useing it every since.

[@markrigneymd6570]

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?

[@Allan_aka_RocKITEman]

I *think* the McDonnell Douglas NOTAR helicopters used this for anti-torque control versus having a tail rotor.

[@SL2K2000]

could you have a curved base too...with another fan just underneath the other...sort of suck the air back in from the bottom making a continous loop of air?.....not self sustaining, just a bit like a turbo

[@kharu1975]

Henri Coanda was born in 1886, in Bucharest, Romania , yep he was a Romanian inventor :) .

[@tirpitz19]

So ?

[@kreazyv8]

so the air is bend down, thus creating uplift trust,, but the force needed to bend the air issent that equal to the lift? and thus creating no lift? next would be the counterforce to get the engine/rotor to spin? the whole machine/contraption wil start spinning. feels like,, oke we got something here, but needs some tweaking to get it to work...+i wonder if it wil be energy efficient?? just food for thought i gues...

[@GiesbertNijhuis]

Thank you! And I enjoy doing the experiments & sharing the results.

[@truvak]

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.

[@dumicris7737]

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

[@AngerSlaught]

dumicris But you don't know what the saucers are made of. Maybe the material of saucer helps the flow of the air.

[@truvak]

TheTechnoJunkee good one. Maybe the design of the material might help too, like the scales work for fish.

[@d4ni5h]

The atmospheric pressure will only be apparent whilst the object is stationary. Flying sadly would be out of the question.

[@truvak]

even if there are flying drones using this effect? they look real.

[@GiesbertNijhuis]

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.

[@GiesbertNijhuis]

The Coand effect and the vortex, are two of the many things I didn't learn at school.. !

[@oboomabom]

How did you make the smoke? I've been looking for some way to make some with house hold materials but I couldn't.

[@ms.digitalpiggy9274]

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 KZbin and Google search is going to look like.

[@osmick15]

High velocity air means low pressure. So yeah this makes sense. Atmospheric pressure is greater than pressure of the air coming out.

[@selectheowl]

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??"

[@GiesbertNijhuis]

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.

[@igloo54]

"It's all fun and games until someone gets their eye poked out." --Famous quotes that all mothers say

[@jaesong5490]

great work! I want to make one! Where did you get that fan? can you list your materials?

[@VTOLKits]

Great demo...!

[@ssaifulhaq]

This is why, the world feels so mysterious.

[@airghandy]

the toilet paper demo is priceless (-:

[@carlosgroi1804]

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…

[@jimmartin7899]

Could you not design high speed trains with a nose like this to generate a semi vacuum like state to reduce friction has the train speeds down a track or tunnel?

[@RafaelFantastic]

Could this be used to pull a plane forward? I saw the part of the video that the commentator said that it could be used to pull up.. but.. what about forward?

[@G777GUN]

Did you know there was an airship that used the same principle for thrust. Its really interesting.

[@125varma]

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 :)

[@lalalu7866]

Have a question why the paper under the chair getting suck up

[@GiesbertNijhuis]

Good observation! The paper (plastic really) under the chair/on the table, is being blown up by an invisible vortex ring that is in between the table and the white curved coanda bucket. This vortex ring is powered by the jet of air coming from above, from the coanda bucket, all around the bucket and the table.

[@lalalu7866]

​@@GiesbertNijhuis trying to understand how its work and how the airflow making the plastic blow up 😅😅

[@thomascrowe3407]

Great report, Engineer First Class!

[@phrenzy1]

Excellent demonstration and a great video. I was wondering whether you get a laminar airflow over the curved surface via the coanda effect?

[@ryobie1]

If you flip the apparatus does the air get pushed up?

[@LokarTheMan]

thank you for making these amazing lessons and videos!

[@nunchuckerz]

would that create lift if turned upside down

[@ticthak]

Isn't this the Venturi effect folded into 3D?

[@29radux]

No

[@Andrewlohbihler]

This effect is not practical to fly saucers because it does not generate enough lift under the craft itself, much less than using a simple propeller to do the same. Even a hovercraft's generates more lift from trapping air under the craft if you blow the air under and add a skirt.

[@Andrewlohbihler]

***** So you are telling me that by blowing air out the top and spinning the outer shell, consumes less energy overall than using a helicopter blade overhead, and generates the same lift profile?

[@Andrewlohbihler]

***** If you are right, then why don't we see more of such curved hulls on VTOL aircraft now? There is obviously something impractical about this design for a "flying saucer" like aircraft.

[@dan16000]

Andrew Lohbihler It's not practical today because we don't have the technology yet. What is special about this principle is that it allows LIFT without any moving parts. Unfortunately, all energy *efficient* ways of creating a stream of moving air today require moving parts like fans or propellers, so it is redundant to use this kind of technology today. Also, the principle is very effective in theory. These type of craft, in theory at least, are the most efficient way if you want to build something that can fly horizontally super fast and also hover very efficiently.

[@Andrewlohbihler]

dan16000 So what needs to be done to make this technology a reality? It seems like the AvroCar was a good example of this technology developed in the 50"s but did not take-off (pun intended).

[@dan16000]

Andrew Lohbihler Develop simple, light, small, cost effective, efficient non-moving fans.

[@flamencoprof]

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.

[@michaellichti5394]

Finde ich klasse, Viktor Schauberger war doch in der Sache doch auch stark verwickelt?

[@Zreknarf]

1932.. was it ever built and tested?

[@TheGodParticles]

Thank you so much for explaining this! I truly enjoy your experiments

[@Xenro66]

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

[@ClearseMedia]

This sounds like a title for an epic action film.

[@mattcintosh2]

The smoke at 2:00 sure looks like they are crossing the streams...

[@hgmg1599]

What is the difference or relation of this to the magnus effect?

[@badpitt6909]

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.

[@superluminal89]

How much to build the BLADELESS JET?

[@boboala1]

That and did you account for the suction effect of the fan pulling air into it?

[@wordreet]

Well the one in the vid deffo looks like one! :¬D

[@scheerBOM]

You have to get a bigger black board

[@francism7287]

eye witnesses said that flyin disc are not noisy...maybe they used the gyroscope effect for flyin disc...

[@Snarky79]

Was the bung fodder clean or 2nd hand??

[@SanthoshKumar-bm9kh]

I've seen many videos about caonda effect and in all the videos they use a rotary motor and explain it. How could the coanda effect in a normal airfoil (jets) be explained?

[@TheWindGinProject]

+Santhosh Kumar I like the way you think. You could do the experiment yourself with a hair dryer blowing against a similar curved surface. Cheers!

[@SanthoshKumar-bm9kh]

+TheWindGinProject I tried simulating the airfoils in solidworks and the air just does'nt completely flow over the surface when i increase the angle of attack(6 degrees). any suggestion?

[@TheWindGinProject]

+Santhosh Kumar Hi, Well as far as my experience goes with CAD I find simulated results to be interesting and mechanically accurate but I believe that unless you have an super expensive add on that does fluid dynamic simulation (( and )) you have been trained for this specific software you should not expect accurate results. I truly believe that a hair dryer and a curved surface would get you close. However I think asking on the SolidWorks Forum may offer other thoughts better than mine.

[@SanthoshKumar-bm9kh]

+TheWindGinProject really thank you for your advice :) I'l try that.

[@TheWindGinProject]

+Santhosh Kumar Thank You, Your question is a good one. I don't know the answer. I hope you find it and report back. Peace & Best Wishes.

[@theRealPlaidRabbit]

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.

[@filmefranceze287]

For those who don´t know , Henri Coandă was a Romanian inventor and aerodynamics pioneer.

[@rexscuz]

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

[@willyjensen8595]

Nice demo of Bernoulli's principle.

[@CariagaXIII]

i just love the engine sound