This Genius Propeller Will Change Transport Forever 

fard

Very Interesting video. Unfortunately, in the economy we live and use, more efficiency means more expense. So all the gain goes straight out the window. Slightly explained by "economies of scale" but do you really believe that ? The sales argument will ALWAYS be "But you'll be saving 20% on your fuel bill" so in effect replace the *saved" fuel by paying MORE for the solution ...... It's a sad world we live in when all and everything is motivated by gain and greedy people. As soon as you step out of university and join the commercial world this will hit you strongly.

This design is over 35 years old

@@supyrow YES exactly. Instead of being economically sensible, the people in charge of making money with things have decided to price it out of the market. Pity it isn't mandatory to study physics AND economics along with English.

The absolut efficiency cannot be even 100%, to reach 100% energy efficiency, you need to have no losses at all, that's not possible. You will always have some losses, in useable Energy.

Ahah no shit ! Once it was broken i bet it ended up on a trophy shelf ! Like all the best manmade tools we do!

That boat owner is a disrespectful person with no integrity

I don't blame the fisherman for wanting to keep a State of the art rotor blade

@@ChinchillaBONK he lacks tegrity

It’s hard to believe that since 1971 no naval engineer had developed it, knowing that propellers are one of most refined and studied piece of a boat

Bumping

Lol I'm a big fan

Lol I'm a big fan

I see what you did there, ha!

I'm just blown away

not a breakthrough. Its old story

Nope not even close, it’s just two regular props welded at the tips. Having two regular counter rotating props on one shaft would be better, some submarines do this. Really you can’t engineer better props unless they have more blades prop engineering peaked at isambards great eastern which had 6 or 8 blades

A design like this lends itself towards an additive, rather than a subtractive machining process. Twenty years ago, the idea of 3d printed metals was just that, an idea. Perhaps twenty years (OK, probably more like 50 years) from now, the idea the idea of subtractive machining will be primitive, much the way we think of the hammer and anvil today. Machinists who haven't even been born yet will look at the rusty 5-axis CNC in the back corner of the shop and think "How could anyone have ever made anything with that hunk of junk..?"

You should have been involved in the making of this video. Roughly what RPM'S would cause cavitation and vibration for this design? @livefire81

Why wouldn't it simply be a matter of making one model that works as well as possible, then making a mold and casting them? If not for transport maybe there's some low rpm applications where the efficiency and lower turbulence make it a better propeller design? Moving gases and fluids is such a broad range of applications.

Why not produce a 180 degree bent strip, welded to the hub instead of a 3-d cnc tunneled design?

@@fladave99 ​ @Paul Zulauf quote: "vibration during high RPM, which absolutely destroys lower ends" unquote If your bent steel strip rips off the rotating axle due to a bad weld, your boat is dead in the water. Also, if you use castiron instead of high-tensile steel, you can say bye bye to your prop. Water is not compressible. While i see the functionality for this with gas and in small drones, with a fluid and large ships you possibly need a sci-fi material (like the base for the Ringworld) to make this work reliably.

My dad loved boats too, i share the same feeling.

It's a scam, these props have been around for 50 years, there's a reason you don't see them anywhere.

@@alittlebitgone Exactly, the maths hasn't magically changed in the last 50 years....

@@alittlebitgone The reason being the difficulty and cost of making them?

@@alittlebitgone Lol, in that case, knowing my Dad’s very precise engineering mindset, I would have probably been in for a lengthy, detailed lecture on the subject!

The noise reduction and efficiency (resulting in longer flight time), will definitely interest the UAV community. I'd buy them TODAY if I could buy aftermarket props for my DJI quads.

Problem is, they would cost a fortune because they are way more intensive to manufacture and need extremely low tolerances. Basically, you won't see this thing on regular people quads anytime soon, if ever.

@@iwontreplybacklol7481 So we have to invest in cooler 3D printing technologies for home application, like carbon fibre tucked in with the strand, and use eg ultrasound sheer waves to mix it with existing layers and have more cross linking between strands of print-out. Also, I would like to have multi-head extrusion in miniature size crawling relative to each other. But hey, future just begun ;) Silent aircrafts are lighter-than-air ships, and use props only to navigate, not to levitate.

Agree on the first part but I have my doubts when it comes to crash resistance.

@@iwontreplybacklol7481 I don't lnow for sure. What if it is possible to find the right stretchabbility and do it like a sail? Will ist self-align into optimal path? This should be the way... of the genius propeller ;)

It's wild how the all the answers are written on the walls so to speak in sacred geometry

Exactly what I was thinking. We simply don't know yet how much more efficient ordinary every day objects can be made.

Yet people choose to obsess over things like gender and race

@@stanhunt8543 They started this in 2015 on a much bigger scale to entertain the stupids, like inventing new genders and pronouns.

There is no limit to perfection. Нет предела совершенству.

Ukrainians are rubbing their hands together

You could try 3d printing your own... I'm sure there are some designs available online.

I see drones using this quickly, as the props are made of plastic.

Hope this trend dies NGL. Kinda annoying left and right videos of people 3d printing and flying them. They don’t even perform half as good as normal propellers half the time. Few days or weeks and this trend will be forgotten

As a blablablabla....if i had a buck for every obnoxious egomaniac using that phrase in comment sections....

From a comment above......This propeller design originates in Tasmania in 1971. It was developed by D B Sugden, an engineer consulting to The Robbins Company (a US company out of Seattle, specialists in hard rock tunnelling machines). The Robbins Company financed an R and D project lasting 2 years in collaboration with David Sugden. I joined the company in that year, thus I speak with some authority. We built and trialled a series of propellers from about 10 inch to 30 inches swept diameter. At that time the difficulty was reproduction of form, a problem which, as you point out, is overcome by CNC capabilities and 3D printing. Trials and wind tunnel testing demonstrated significant performance gains. I recall that a large prop was provided to a fishing vessel owner on the understanding he would trial it for a few months. He refused to give it up because it was so good when the trial concluded. The manufacturing difficulties of that time precluded further development..👍🙂

Would casting have been too difficult?

Would this prop design be viable for aviation?

Warp speed?!! "Engage Mr Scotty...."

@@keldonator had the same questions.

Great point, I didn't think of that!

If we are really talking double the efficiency, it will still be worth it.

Submarines, silence is survival so less cavitation is a massive plus.

@@Invisiblehand123 We're not. Check the graph at 2:04. There's a big jump in efficiency at a certain RPM range but outside of that range, it's not anywhere near that big. In the 3%-7% efficiency gain ballpark. And that's *if* you trust the companies numbers and I don't think I would without 3rd party verification. That being said, *if* the company is true to it's word and *if* you're running a proper shaft in the 3500 to 4500 rpm range, it's great news. Of course, the big stuff only moves props at around 200-300 RPM so, that's well outside the range this thing is meant to help at.

@@ColonelSandersLite Interesting, thank you for your input.

I hope so!

Metal 3D printing will help a lot with the cost, but it is also still in the development

China sez how many u want and what sizes we will deliver them by balloon.

Yeah hopefully! $5000 for a boat prop... No thanks.

@@ZirothTech ⚠️ God has said in the Quran: 🔵 { O mankind, worship your Lord, who created you and those before you, that you may become righteous - ( 2:21 ) 🔴 [He] who made for you the earth a bed [spread out] and the sky a ceiling and sent down from the sky, rain and brought forth thereby fruits as provision for you. So do not attribute to Allah equals while you know [that there is nothing similar to Him]. ( 2:22 ) 🔵 And if you are in doubt about what We have sent down upon Our Servant [Muhammad], then produce a surah the like thereof and call upon your witnesses other than Allah, if you should be truthful. ( 2:23 ) 🔴 But if you do not - and you will never be able to - then fear the Fire, whose fuel is men and stones, prepared for the disbelievers.( 2:24 ) 🔵 And give good tidings to those who believe and do righteous deeds that they will have gardens [in Paradise] beneath which rivers flow. Whenever they are provided with a provision of fruit therefrom, they will say, "This is what we were provided with before." And it is given to them in likeness. And they will have therein purified spouses, and they will abide therein eternally. ( 2:25 ) ⚠️ Quran

If it sounds too good to be true it probably is.

"boat can holy"? What do you mean?

If you use 20% less fuel, it makes your maximum travel distance 25% longer.

@@noredine amount of fuel the boat can hold

​@Nick Christiansen this video literally demonstrates how the propeller works and how it's better than conventional propellers

No, not on helicopters. The dissymmetry of lift would be a huge problem.

Interlake is looking for people!

Thank you

Or we can add second propeller which nullify centrifugal force.

And on airliners, too.

@@larispostae42 can't aply this on jet engine.

The screws on big cargo ships do not spin fast enough to have tip vortices problems

This is only helpful for small high speed propellers. Great big ships don't have big losses at the tip and are already way more efficient than this. You just can't put a big ol screw prop on a tiny little jet ski or motor boat, so this is just a good compromise.

I can't wait to fit these to my whaling fleet…, Gonna sneak up on those fat ass Wales no problem.

at least one person saw the obvious click bait title for what it was.

105% compared to what. Dont let your ego obscure your judgement

@@disruptivegarage read the title...doesn't say "more efficient"...literally says "efficiency". Don't let your low reading comprehension level obscure your judgement. ;)

@@Raussl So, what part of the hyperbole isn't using 105% in a title, and what is the base efficiency? It's like the song, " Compared to what?"

@@tauncfester3022 that is not how you use the English language to express that one machine is more efficient than the other... Again, if something has a 100% or more efficiency, it creates energy from nothing.

I doubt this is suitable for merchant ships. Too expensive to manufacture and maintain. Development and testing for merchant solutions would likely be sky high and would put off many atempts for this solution. For the commercial shipping solutions where this could make sense the preffered choice is likely a ducted propeller, which is much easier to manufacture and probably have similar properties. The comparison to a standard fpp is therefore not valid. High saftey requirements combined with a low margin business makes shipping companies conservative in their choice of technology, so a steep hill to climb. If it would prove to have superior noise reduction qualities it might become a choice to concider as regulations might require so in certain areas. Cavitation is always also a concern. Any commercial solution on a merchant ship would require that it is repairable and this means that steel and full composites are poor choices. Any repair also needs to be possible at any repair yard. This would likely require OEM engineers and supervisors. A brass propeller would likely either not have the strength required for this kind of complex structure, especially if the ship needs to have some ice classification.

@@TheButlerNZ I see 105% on the chart in the video, but it's only 105% increase over the normal propeller at a specific RPM - there's nothing that breaks the laws of physics there...

Low speed merchant ship props are already more efficient than high speed pleasure boat props. Study a prop curve and you will see why.

@@TheButlerNZ the thumbnail says "+ 105%" for me. Not "105%". That's a big difference.

Well I looked into this about year and a half ago and can attest to at least 1 number…. They are expensive

Major hardware tried it, didn't beat a Noctua.

They tried it with a rough 3d printed model which was eyeballed caus he couldn't get the schematic from MIT. Also the design that he based off was designed for a drone in open air, not the focused airflow needed in a PC case or similar. This design has potential but as mentioned in this video, it needs to be specialized for each application, as all fan designs do

Are you running fans at 2-5k rpm? Because if not, this won't help you.

@@declanfitzgerald1005 yeah... He needs to get a real printer. I'm pretty convinced a lot of the blade design submissions could beat a noctua if they didn't have horrible fdm surfaces everywhere. A lot of the designs on there would be epic with a resin printer.

@@CaedenV Thats what annoys me with his videos and he doesn't talk about it. The tolerances he gets are terrible compared to for example noctua's with the tiny tip clearance that they needed a new material for. It's just not fair to compare fan designs when the material is so different, but he acts like that's the test and here's the conclusion, end of story.

Someone probably did think of it earlier, it's sort of an obvious idea if you start to worry about tip vortices, but it's a very complicated shape, probably only recently had good enough fluid modelling / rapid prototyping with 3D printing etc, to be able to get it to work well enough to be worth the effort.

We've been trying this for wings since the dawn of flight, and we actually understood why it would be a good idea to do so at least a century ago. Applying it to a rotating propeller is vastly more difficult than a fixed wing.

It was thought of long long ago. It's one of those things that has to wait for manufacturing to catch up. For real world applications en masse it has to be cost effective and reliable.

They have it's just they are only better than a normal prop or blades around a certain RPM so it's rather case specific and as he mentioned for bigger ships.. It won't scale up for them because their props are fairly low rotation.. These work best at high speeds where the tip of a normal prop is hitting super sonic (in the material) speeds.

$5000 v $500

you could probably just rotate the whole circle of the blade

The prop governor adjusts pitch, not the blades themselves

@@Pickle117 Never said otherwise. The net effect is still blades the pitch of which can vary, hence the well established term "variable pitch propeller"

@@levistewart5610 Sure, but the blades themselves are still fixed. Helicopters for instance require both to be variable.

A fan blade like this might be more useful for jet engine compressors than than prop plane propellers. There would be no need to change the angle of the attack

What physics are you talking about? This is a scam. I read the paper and there is absolutely no data of any kind that support their claims. Not even the decibels which they claim it "reduces". They only showed a stupid animation, not even a simulation which requires real data. They only did it to earn a price in a MIT competition. Otherwise, where is the data?

It seems pretty old design, and would be in wide use if some mass production would make them viable for mass use. Overall, it seems like there are significant hurdles to overcome when it comes to manufacturing. That said, with current manufacturing capabilities it should be viable to use this, especially with high value machines. But from what I gathered it's not so I assume there are some other limitations. At least taking this video at face value, improvements proposed by this design are insane, and even if the propeller was significantly more expensive, it would be worth it for many boats/ships. Especially in shipping and other commercial applications, there's just no way they would miss on significant fuel savings this would provide. So I have to say I'm suspicious that a lot of information is being left out. I just can't see manufacturing cost being an issue when it costs crazy amounts of money to fuel a large ship.

At $5000 a propeller, it cost more than my boat. Propellers have different pitch and diameters. It doesn't seem feasible for someone to have to go through multiple propellers to find the right one for their boat. Until it comes down to around $200-$400 range, only few people will buy one.

@@ahndeux For normal people and very small boats this probably isn't worth it. But moment you are using boat for commercial application, even very expensive propeller should be totally worth it if the claims in this video are true. If not for smaller boats, definitely for bigger boats and ships. So this video still kinda bothers me because looking at comments this has already been known for a long time, and despite that, if ships are not using this design there has to be some fundamental flaws with design, not the manufacturing. From quick googling, fueling something like cruise ship can cost up to one million a week, so really if you are talking about insane saving over time larger the ship becomes.

@@ahndeux so true. What is really going on here is for your $5k they actually sell you a prop with pitch and diameter optimised for your boat/engine. Maybe there is room for a consultancy business whereby for $600 dollars you tell boat owners the optimum pitch/dia/blade number so they can go and buy the $400 conventional prop that is most efficient. And if they really care about the environment they can spend the $4k difference planting trees.

@@XPLAlN If you are a boat owner, you will know that its not easy to find an optimal propeller because the optimal RPM changes. If the boat is carrying more weight, it affects the RPM. If the boat is used for skiing vs a fishing boat, that also changes the prop setting. If you prefer a faster hole shot vs higher operating efficiency, the prop pitch also changes. Another factor to consider is the length of the boat, the hull design, the use of hydrofoils, etc, all affects the ideal prop design. Even the material the propeller is machined out of (aluminum vs stainless) makes a difference in RPM. There are just too many different variables. The best way is to swap props until you get the performance you want. That will never change. Most of my boat owner friends have 3-4 props. Some vendors allow swapping out props for a shipping fee. Let's just say this is not likely to happen with a $5K prop.

suggest you talk to one of the aerospace engineers in you industry, they will soon show you why this is all rubbish, and even worse on propellers used in the air.....

@@quadlawnmowerman why is it rubbish?

@@a.hammad9194 because Quad Lawnmowerman sells standard props.

@@b0nes95 🤣🤣

@@a.hammad9194 Cause both the maths and testing shows it is a rubbish design. You would have to be pretty gullible to think they somehow made a magical 4 bladed prop that evades the laws of physics.... The basic principle at play here is to reduce the area of greatest thrust generation/loading (which is the most efficient part of the prop) by spreading it over more blades...... In other words, less thrust generated for more energy input. No aerospace/aeronautical engineer would bother to research, as soon as they saw it had more blades they would be "nope, won't be more efficient" end of story.

A working concept??? This is a scam. I read the paper and there is absolutely no data of any kind that support their claims. Not even the decibels which they claim it "reduces". They only showed a stupid animation, not even a simulation which requires real data. They only did it to earn a price in a MIT competition. Otherwise, where is the data?

I would like to second that. A very interesting video.

I doubt it. That sounds like a LEDs are shitty solar panels type thing.

Wind maybe but likely not for hydro or any other application in a confined space (pipe /duct) with a cowling which already deals with this tip effect.

It maybe be interesting in some energy sector. But hydropower are already highly efficient up to 95 to 97% efficiency.

@@phetthasonemanipakone7180 well sounds like we got an extra 20% of that

Or helicopters with three big doughnut blades. Wuowouwuow wouw!

On a hovercraft

And the windmill industry, since high amounts of noise are a major hurdle for their acceptance.

Not at the price point they are selling them at

Big ship props don't cavitate unless somebody screwed up.

@@evangatehouse5650 Yeah, that's right of course, I should have been more clear. IF it happens, cavitation is a big problem. My thinking was that the helical design could spin faster and produce more thrust *without* cavitating :-)

Cheer for watching bro :D yea that's a great point actually, would be interested to see a 'crash test', may be harder to repair small bits of damage too

@@ZirothTech Exactly my thoughts. I was thinking especially smaller boats that in low tide sometimes clip the sand or hit foliage it might be a potential issue. Would be interested to see how they fair up. Definitely would be ideal for passenger larger vessels! However, as you mentioned with the lower RPM, may not show the same efficiency (or noise reduction) gains as a faster rotating prop. Either way, definitely a cool and purposeful design that isn't overly complex, so there's hope it becomes cheaper to produce once it's more widely adopted!

i'd like to see them made from aluminium - they're less rigid and while they would damage more easily, they'd also be easier to repair

My initial impression is they would be harder to damage than a conventional prop.

@@charleslyster1681 and considerably harder to repair

Well halfway through and the boats engine noise was bs, most of the noise is from the engines themselves, there's absolutely no way a propeller makes an engine more silent.

not a new design, not used due to being very inefficient...

@@quadlawnmowerman inefficient in what way…please explain??

@@russellking9762 Read a 101 on prop design, to over simplify for people who can't grasp the basics. The most efficient prop is a single blade, but that is a pain to use so we go to 2 blades to make balancing and mounting easy. The only reason to add more blades is due to limitations of either size or rotational speed (or in some very limited cases a greater disc area for more "grip" and initial acceleration in say an aerobatic drone where the sacrificed efficiency and top speed are irrelevant). So with 2 blades we generate an amount of thrust (lets say 10NM) for a set amount of energy (lets say 100W to keep round figures), when we add a 3rd blade we up our thrust by about 30%, but we cost another extra 60W of energy, add a 4th blade (which is what this toroid is) and gain another 20% thrust, and cost another extra 75W of power. Every extra blade creates less thrust per blade and costs more energy to drive. This is then magnified by the fact the main trust generating part of a prop blade is not generating thrust in a toroid (at the ends of the blades). Add on top of this the overlap in the blades and you now have one of the least efficient forms of thrust generation, and is only effective in thrust generation at much lower speeds before stalling. So you have a prop that cost more energy to drive, delivers less thrust and is severely limited in its rotational speed....

Probably, but not likely. It work best on in high speed area.

Nice Suzuki bike and BMW car collection

@@HTV-2_Hypersonic_Glide_Vehicle Tks!

this

All drills have a chuck But they dont all have internal components to make them last longer. The ones with less parts are far cheaper. I wonder why people buy them?

Yep, I'm not even going to watch it because 105% is nonsense, so I assume most of the video is dubious too.

They could use it in computers too for cooling the insides.

3d printers are affordable nowadays, I picked one up under 300 If only I had time to use the damn thing lol

Can we talk about your cool moniker? Nice going frawg.

@@theodoreolson8529 Thanks. I'm just your average, everyday frawg... from space.

I would also keep in mind that a more efficient propeller means they are likely achieving the same speed with less engine rpm. That difference in engine rpm is probably responsible for most of the noise reduction.

Fans, leaf blowers, and hair dryers are all ducted. You don't need a toroidal closed airfoil to reduce tip vorticies. On a fixed wing aircraft, this would be a biplane, which is inherently less efficient due to interaction of the two wings, and only makes sense under other constraints, such as wingspan limits or structural rigidity. Helicopters just want big long rotors, for the same reason as wings.

Is the difference in sound really that big of a deal?

There may be potential gains with a polished thin metal set of blades (vs said poor 3d printed blades) but at that point the cost over efficiency gain might just make it too costly

The poor surface finish quality is negligible when comparing performance. It greatly influences noise levels though. These won't benefit from the toroital design as PC fans already are enclosed on the side preventing turbulences.

@@xanthopoulos1825 It seems like the biggest gains with a torroidal design would be the directionality of the flow. It seems like the scoop tips of the fan blades being connected really prevent the blades from casting off air flow in any direction besides straight back. The problem is I don't know when you would want that.

I think sharrow intentionally only did comparisons with single props, since the upgrade would be less significant over a duo. Something not mentioned is that conventional props can often be repaired if they get a small nick or bend from a collision, using something like PropScan. The toroidal ones would probably be trashed however, until they come up with a much more sophisticated repair tool

If they don't handle larger diameter size, you could simple install a circle of multiple rotors around a cingular drive shaft to get a similar effect in terms of thrust. So instead of one large prop, you have five or six smaller ones all driven by the large motor.

@@matthewbrown5228 yeah but weight and complexity. And price too if they're hard to manufacture.

Turbine blades are enclosed in the cowling, plus the blade tips are mere millimetres from the edge of the cowling specifically to limit tip vortices. Not sure this would work for jets.

There is more versions of this prop to be expanded on. I think it is genius and I think there is going to be applications of it in every propeller based system in the coming future😁

@@Future-Preps35 Seemingly most aircraft use variable pitch propellers, it seems that would be difficult to impossible to achieve with this design. Not being able to feather a prop when there's an engine failure would also be a safety issue. Reverse thrust would also be lost on those planes that currently have it.

It wont. This prop tries the offset the disadvantages of not having a duct, it would be inferior in more ways than one

drone delivery will be a thing if they solve its reliability and safety to fill our standard. no one want to be chopped on the head by anything right?

i think that helicopters change the pitch/attack angle of individual blades so probably it wouldn't work out

They are comparing the same speed. So he was probably running less RPM for that speed.

@@BertM3 Which nonetheless shows the advantages of the Toroidal propeller as it requires less RPM to provide the same speed.

@@phasorthunder1157 It's more in reference to the noise. A few hundred RPM difference can considderably alter the noise coming off an engine. But you are right, it shows the added efficiency of the Toroidal propellor.

You're still only moving the same amount of media over the wings as in a traditional rotor design. On a helo, the mast head design would get highly complex, and likely not feasible over a more traditional design.

And yet sulfur is a key element in plant growth, what'r ya' gonna do?

@robertmarmaduke186 you are thinking of just plain sulfer you find in fertilizer. Ships burn fuel oil that produces sulphur dioxide which is toxic to plants. And humans. And creates acid rain. But what'r ya' gonna do?

@@TheBCninja You're right, I probably should've made that distinction earlier.

I figure it would be quite expensive to build a propeller that massive.

Unfortunate that a cleaner burning fuel would also be prohibitively expensive to use for ship fuel, would be pretty cool to see them use something closer in pollution levels to unleaded gasoline/petrol (still *terrible* for the environment but slightly better than bunker fuel)

Like other have said, it's only for high rpm. At low rpm the mentioned vortex isn't forming so there is no gain in efficiency for this design

I would add test how they work in a contra-rotating duo-prop setup as is now the common setup on pods.

3:02 Answer is crystal clear.

As displayed in the graph presented in this video, the improvements are considerable in narrow band of rpm, and noticeable in others. I bet this can be tweaked by design, but this is not a magic bullet that works super well everywhere. Seem very promising though. Eliminating cavitation will prolong prop lifespan by huge margins in boats, so the efficiency is not the only plus here.

The shape could be optimized to certain rpm range, but it's most likely not possible to have a universal one that's great at all rpm range. Also for something like drones with very high rpm props, it seems to instead reduce thrust at the same rpm range, tho those findings are all coming from amateurs so far. Not sure if it can be further optimized for working well in high rpm, but it doesn't seem all that great so far. Even if it were to reduce noise, if it decreases the performance significantly, it will probably be a no go. Tho all these amateur tests have no scientific backing tbh, they are mostly just eyeballing it. So it will be interesting to see if something better will come out.

@@N0xiety nothing different than any other propeller used on boats then. Good thing there is software that can test designs against hull shapes and prop speeds.

Ooo, that would be a nice application right there. Someone send a design to that one pc fan testing channel on here!

Fan Showdown already did a video on using this design for a PC fan. The conclusion was that a 3D printed toroidal fan still couldn't beat a Noctua for both quiet operation and performance, likely because the design was intended for high speed (e.g. drones) instead of the lower speed of a PC fan.

@@randomsandwichian Here's the video from the fan testing channel you're referencing: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-4ImeOKgD_Dw.html

The duct already does everything the closed airfoil is supposed to, and does it better. If you want noise reduction, you want curved edges, optionally with chevrons (or "teeth") to break up any coherent pulses.

No, they definitely won't

Turbochargers would be using them if it were more efficient