Thank you all for watching and the interesting comments, here are some points to address the main ones I have seen: - Great points about how this may be manufactured in the future, part of the economies of scale I mentioned could definitely include injection moulding or similar. - Durability is an interesting point and I would love to see how the blades fair in a 'crash test', they may also be harder to repair? Let me know your thoughts. - The gain in efficiency is 105% when compared to the original values (38% to 78%), it is true that absolute efficiency cannot be over 100%, but increases can be. Such as a company seeing a 200% increase in profits, for example. - Many saying that reduced cavitation may also reduce wear on the blades, making them last longer in boats. Great point that I didn't think of!
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.
@@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.
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.
Im a CNC programmer who worked for a top tier marine propulsion company for years. Our company has been in the R&D phase of producing a prop similar to this for years to no avail. We produce the Volvo-Penta dual out drive props and Volvo is/was very interested in this design. The main hurdle we couldn't clear on this design was cavitation and vibration during high RPM, which absolutely destroys lower ends. We even consulted top level fluid dynamic phd's from University of Michigan and still haven't cracked the code (pun intended), as of 2019 anyways. I had to work hand-in-hand with our engineers on this project and I can say with 100% certainty, these style prop's are a bear to machine, even using state of the art 5-axis mills, the tolerances are crazy and the balance has to be absolutely perfect to mitigate the issues I mentioned above. I've produced some highly technical stuff in my career, including Govt. projects like the Navy's SWS submersible troop transport vessel to high end Hatteras, Bertram and Bollinger Shipyard 5, 7 and 8 blade NiBrAl, Bronze and Stainless steel props for luxury yachts and cargo vessels alike. All that being said those projects were a cake walk in comparison to this design. I don't miss the stress, twisted steel & broken tools. I was on a 1st name basis with our Dapra tool rep after trying to machine these.
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..?"
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.
@fladave99 Mills @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.
Well well well, we have an expert over here. Interesting stuff. So what's different now, why did the people in the video succeed where you guys failed?
I could see this being interesting for FPV, quieter at the same performance and potentially greater crash resistance with the right materials. Not to mention it would probably hurt a lot less to get hit by one of these props compared to an open blade
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.
@@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 ;)
So exciting! My dad was a metallurgist and cast many large propellers for military, cargo, and passenger vessels. I wish he was still around so I could share this with him. Thank you!
@@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!
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
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
Cavitation also is responsible for a great deal of wear and tear, shortening the service life of a propeller. Given that even smaller propellers aren't inexpensive, consider replacement costs on a cargo or military vessel.
@@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.
Back in the 70s I ran into this toroidal propeller design in patent reseach. While attempting to design a constant torque variable pitch propeller myself. Must say I was very impressed at the time. In my own study of the toroidal design I drew the same conclusion of machine shop limitations of this design in manufacturing on a commercial level. But an extremely viable concept since the invention of 3 axis cnc machinery on an industrial scale. The shape does redefine the term of warp speed,, due to the warping of edge chines in this design.
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..👍🙂
As someone who is looking to work on a bulk freighter on the Great Lakes, I would love to see these props tried on the large freighters. Hopefully they can make the ships even more efficient and comfortable for the crews.
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
@@flask9712 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.
@@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
It's HILARIOUS how the commercial before this vid starts with "Don't be fooled.." 😂 These are quieter, but they're far from more efficient. Don't believe me? You will in a year or two. They won't figure out how to make them as-efficient+maneuverable+ this much quieter for a long, long time, if ever.
Makes me curious a few things: 1) the electric Candela C-8 hydrofoil has an 80% fuel reduction once the hydrofoils are turned on. They use a counter rotating double prop configuration. What would happen if they used a toroidal prop? 2) can & is there any benefit to using counter rotating toroidal props? 3) cab bionic propeller configurations be incorporated into a toroidal design? With any added benefits? 4) vs counter rotating, what if made longer? In less a HAWT design and more a VAWT design where they could run through multiple toroidal twists? 5) now make those longer/multiple toroidal twists counter rotating on the same shaft.
2:54 I think that it would be good to point out that the RPM at the bottom of this graph is the engine rpm. So in case of the Mercury 400 L6, (the V10 model has been out for so little time that I assume it's the old L6 model) which has a 1.75:1 gear ratio, the props are actually turning at ~2300rpm at the mentioned 4000rpm engine speed.
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.
A couple of thoughts that pop into my head from this: 1. I hope all the numbers presented hold up! 2. I sure as hell hope this scales up for large cargo ships. More efficient and quieter, that would be amazing. Ships already outweigh all the fish in the seas iirc, so a change like this would have a HUGE impact. 3. That noise comparison? Now imagine those being electric motors. The noise difference adds up. Insane change for the better. Love it. 4. This reminds me of a video I saw showing a potential new main wing layout for airliners that NASA is thinking of funding large-scale testing. A wing shape that is basically this shape! The wing goes out, smooth curve upwards, goes back in again to attach to the plane further back.
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...
@@Pickle117 Never said otherwise. The net effect is still blades the pitch of which can vary, hence the well established term "variable pitch propeller"
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
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.
This is proof we still live with in a modern era despite how postmodern the world may seem. We are still inventing and growing our technology to this very day.
It would be interesting to see whether a variant of this would be suitable for use in energy production plants, such as wind farms or hydro electric dams
It's amazing how the toroidal propeller draws the water in from surrounding areas as shown with the dye in the water test. It would be great to see more of them and more manufactured to bring down the cost.
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.
Fascinating topic and well presented - as a lifelong power boater I certainly love the idea of this so far untapped potential efficiency gain. And as someone involved in the emerging advanced/urban air mobility industry I’m interested in mitigating what will almost certainly be the impacts of community annoyance to noise. Subbed!
Very well done video. I’m in the aerospace industry and did some pretty intense research on these a few weeks ago… and you covered almost every point I looked into :) something interesting is that like you said, most large rotorcraft have slower spin speeds, but a neat exception is in the tail rotor of helicopters. They tend to spin pretty damn fast
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.....
@@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.
Propeller efficiency is also looked at the large scale. Adam Savage did visit Archer Aviation for a demonstration of their E-VTOL demonstrator. One engineer talked about propeller noise and how to reduce it with fluid dynamics simulation. It's all about vortex shedding and tip speed. Don't forget: airliners have jet engines which blade tips (of the main fan) go supersonic - this is why they are so damn loud... ✌️ Another example: CFM RISE, which is based on the research of the GE36 UDF (his was the engine for Boeing's planned 7J7 airliner). The RISE has special external blades and static blades directly behind them. All this is geared towards efficiency and noise reduction and will come to market within the next 6-8 years. 😎
The lower efficiency gain of the boat prop at lower rpms is probably because there’s little cavitation of the conventional prop at those speeds to begin with. Scale up the size though, and cavitation is a big problem for ships props, despite their low rpm,
@@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 :-)
That's mad, always love me some efficiency. Hope these become the norm in the next 5-10 years! Less of an issue than the other aspects in the majority of cases, but would be interested to know if they are less (or more) durability in the instance of hitting something.
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 would also be interested in seeing how the new prop design does in the standard pontoon environment. I.E. weedy low water level areas. Seems like pulling up to the local sand bar for a couple beers and touching the prop on the sand at a low RPM would transfer significantly more torque load to the lower unit causing significantly more damage than you would have on a traditional prop. Very cool design though and glad to see innovation on a product that seems to be unchanged for so many years.
Since a few years back now ive been drawing propellers in this exact shape, but my gf always just finds em amusing. ”Looks simple enough, dont you think people would have made it already”. Im happy to see it actually works! Cheers :)
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?
This is awesome, and the type of thing that needs to happen more: small incremental changes that yield gains in efficiency, but across more areas, would lead to massive gains across society.
a number of questions here for people curious about wind turbines: - wind turbines already have enormous blades with manufacturing difficulties - would these compound with toroidal design manufacturing difficulties? - wind turbines have much lower RPM than propellers - would there be any benefit? is there a similar efficiency graph for reynolds number? - modern wind turbines often have variable blade pitch - how is this handled on toroidal propellers?
@@disruptivegarage read the title...doesn't say "more efficient"...literally says "efficiency". Don't let your low reading comprehension level obscure your judgement. ;)
@@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.
Very impressive. I've often thought that drones could never be a viable means of transporting goods in a residential enviroment due to the insane amount of noise that standard propellers produce. This altered design completely changes my view of the whole concept now. It makes you wonder if this design could be incorporated somehow into jet engine turbine blades to increase thrust, reduce noise and gain fuel economy. Guess time will tell
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.
Could argue for a smaller (cheaper) outboard motor if fitted with these more expensive props. This could offset some of the cost while keeping the performance levels identical.
This is huge!hey hats off to you for being on top of this type of video, it's seriously a major saving of fuel and makes the boat for efficient through the water.thsnks for the vid.
I find this concept (now an actual working concept) quite fascinating. Thank you young man for educating me with your concise succint video presentation.
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?
A shrouded fan (like you might find in a jet engine or computer fan application) doesn't produce tip vorticies. And, there may be an aerodynamic limit to its use in drones and as a main rotor of a helicopter because those applications demand the prop be moved laterally through the air, not parallel with the direction of travel. The blade going from advancing to retreating might suffer signficant drag at the 12 and 6 o'clock positions.
Fascinating stuff, the side by side sound comparison of the two boat props is a dramatic difference in sound level, I wonder if that holds true in the air, I'd be interested in hearing a side by side drone comparison. This has a wide range of applications; helicopters, fixed wing aircraft, shop fans, leaf blowers, hair dryers. The shape of recent submarine props are classified because our advisories could calculate the subs capabilities and at what sound frequencies they could track them, I wonder if another reason they are concealed from view is because they have a very unique design such as this. If so, this technology could have trickled down, been declassified, due to common knowledge by our advisories, I'm spitballing here but, it's possible.
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.
Also imagine the sound difference when the camera/microphone is turned 180 degrees looking/listening towards the front of the boat. The wind noise from that perspective would probably mute anything else.
When talking about efficiencies and throwing in numbers like *+105%* you should always look at the definition of what they mean with efficiency in this case. Because it is very easy to play around with these numbers.
Just a suggestion that the golden ratio be utilized. The circle that is being utilized currently causes drag, the golden ratio will give it up more efficient cutting surface. The following is a copy and paste from Wikipedia In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities. Expressed algebraically, for quantities a and b with a > b > 0, {\displaystyle {\frac {a+b}{a}}={\frac {a}{b}}=\varphi } where the Greek letter phi denotes the golden ratio
These props have been around for years.. If they were that much better, many outboards would have them... I think the problem is at the tip of the prop there is a area that produces no lift, but does add drag as the tips are going the fastest. This can be done with a reg prop with washout, but if that worked all props would have that too.
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?
One of the most fascinating things about this is that it can be retrofitted to just about anything. As soon as the manufacturing reaches reasonable scale you relatively inexpensively put it into any system (as opposed to putting in a new engine for example) I look forward to seeing this tried at a larger scale to see if the increased scaling of weight (for example a full size helicopter blade) would negatively impact effectiveness. The other portion of this that I'm unfamiliar with is how does this system load, helicopter blades flex rather extensively right now and if this shape isn't able to do that and is therefore going to require it to be more built out certain applications might be ineffective. This is one of those discoveries that makes me scratch my head about how much sooner we might have been able to achieve certain things if we had known about it from the outset
Having retired from Aviation after 30 years I have gained a lot of knowledge in the efficiency of propellers. The biggest difference I see is that the tip of a standard propeller actually breaks the sound barrier, that is typically what makes the most noise and also causes drag and reduces propulsion at the tip. The circular design eliminates the tip of the propeller, making it much more quiet and much more efficient.
I was messing around in my pc this morning and watching the fans spin and thinking how they cause all the noise - this is 100% going to be in every small cooling fan in the world soon. Thanks 😊
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.
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.
This would be an absolute game changer for heavyfuel-using vessels. The 7 biggest container ships produce more sulfur than every car in Britain per year.
@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?
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)
FYI: Efficiency over 100% isn't free energy or perpetual motion. It uses existing energy from the environment, possibly with effects like localized cooling occuring. Heat pumps are a great example of this. Its how you define efficiency.
WOW... real practical information about innovation. GREAT video, Sir. This is a real change. Even as a personal boater, the lower noise profile alone would be worth the cost. As a commercial application, the economy over time makes the initial cost negligible. I have a hard time understanding why this won't become standard within a decade.
@@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.
Use this great propeller on an electric boat, no more noise, very high efficiency. This could be the breakthrough for manned drone flight, such a natural idea, brilliant.
I'm curious if the improvements are limited to certain rpms or of they are present throughout the rpm range. As well it would be interesting to see how these props respond to being used in a ducted environment. Even in an azopod installing... gets the mind going So many additional, and fun, tests still to be done.
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.
Thank you for this great little video I had never seen these propellers before. I hope to see more drones using them in the future due to the significant reduction of noise and the increased efficiency which should also lead to an increase in flight time.
Congratulations.. youve just achieved what no physicist has been about to do, no CERN scientist, not even Tesla himself : deliver a machine 100% efficient. You even went BEYOND 100% efficient, meaning youve achieved the impossible: a device that makes more energy than it consumes. All with a grinder and cardboard. WELL DONE!!
As a boat owner, I find this extremely interesting. As someone who is broke, I heard the price and lost all hope. Maybe someday, but not now or anytime soon.
As others have pointed out, Variable pitch propellers are essentially standard for larger applications (both marine shipping and larger manned aircraft). I'm curious if theres even a possibility to make variable pitch toroidal props. I also wonder if the toroidal propellers would stand up to the increased centripital forces that come from increased diameter. Even if a Toroidal Helicopter rotor would stay in one piece, would it manage to keep its shape enough to retain the benefits?
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.
2:54 Deserves a video from some skeptical engineer channel. Sure, +105% efficiency! On a cherry-picked range. No, this doesn't mean that toroidal props are double the efficiency. It means their peak efficiency range is wider. The props are really only 8% more efficient. Which is still good, but that basically means toroidal props are ducted fans in disguise. With less problems than ducted, maybe. Remains to be seen.
The only negative I can see in boating applications is when the prop gets damaged. A conventional prop may get a major knick in it, but it's performance might not drastically affected. I just wonder if the thinner wall and lack of filler material would cause an issue
As a person with a home recording studio, the computer application for this is something I hope happens. We always have to keep the computer out of the room, or record outside the room.
why would you not just use background noise cancellation from a audio sample of your computer fans? or just use fan software to min the fan rpms when recording?
You might want to invest in a water cooling kit for your computer. There are off-the-shelf ones as well as custom water block kits. Not only is your computer cooler - but much quieter.
It addresses an significant inefficiency in propellers, the "leakage" of fluid from the high pressure side to the low pressure side. It is this leakage that produces tip vortices. Commercial Jet Engines use the stator duct to prevent these "leaks" while high aspect ratio blades are used to minimise them. These toroidal blades avoid having tips, reducing the opportunity for "leaks". A very good idea! Hope it succeeds at an affordable price.
So far I've only seen the Sharrow props tested on relatively high speed outboard engines. On those engines, if you look at the low RPM range (under 3000RPM) the Sharrow doesn't give that _much_ of an improvement, not enough to justify the cost at least in my mind. Large cargo ships rarely run at over 2000 RPM, if that high, so it's doubtful if that prop design would give any benefit to shipping industry. That said, I would love to see a Sharrow type prop tested on a trawler type vessel rather than a "go-fast", just to see if it would give those same (small) increases in fuel economy. . As an aside, the concept behind the toroidal props isn't that new. You can safely wager that the various navies around the world have looked at using them on warships, especially on submarines where cavitation noise is the main cause of being detected. Another item, most marine props are CNC machined, especially performance outboard props. Large ship props are cast and then polished to the final shape.
I would expect that the efficiency versus speed curve would also be massively shifted depending on the dimensions of the propeller under test. Large conventional ship propellers already operate at vastly different speeds to propellers on outboard motors, for example.
Definitely an exciting design, but it seems there is one advantage the standard props have over the toroidal, that being standard probs have the ability to change their pitch. Most cargo ships don’t use azipod thrusters so instead they have controllable pitch props. Seems like a huge design challenge to implement toroidal props on ships that utilize controllable pitch
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.
I wonder if that shape could work on turbocharged engines. Like pulling/pushing more air in to the cylinders or to work with lower emissions at lower RPM's?
Would be insanely difficult to get this to work on helicopters though. I mean the Kaman K-Max uses ailerons to change the pitch of the blades for lift so if you could mount these on a horizontal shaft with a pitch horn it might be possible but I think the torque over moving all that drag producing surface would not make it feasible.
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.
Toroidal design may be the tip of the iceberg when it comes to quieter, more powerful, efficient propellers. You're making headway, mates, keep working at it.
Seems so simple, but the results are incredible! Also, have you looked into putting your content on Nebula? I'd love to be able to support your channel even more by watching your videos on there.
You mentioned cavitation bubbles but missed mentioning the amount of damage they do to the propeller. Cavitation bubbles not only decrees efficiency but also damages the propeller, like allot. Just google propeller damage + cavitation bubbles, and you'll see what i mean. Thus, if this design reduces cavitation bubbles the durability of propellers will greatly increase, larger ship propellers are very effected by this as well, so lets hope this design is scalable!
@Professor Frog Thanks for the info. Still hope to see this tech make a visible change to things. Give things a more futuristic look while still being practical lol.
@@Propane_Acccessories The Osprey also uses variable pitch, it is effectively a helicopter for vertical takeoff/hover/etc anyway. Similarly seemingly most planes also use variable pitch props.
I'm wondering if this blade design could be useful for wind turbines, or not. Probably not due to their angle of attack variations depending on wind speed.
I bet they could use them. The angle of attack could still be adjusted but the adjustment would have to take place at where the prop joins the shaft meaning a total redesign. Likely worth it though.
Actually there is one MASSIVE drawback. As far as I can tell there is no way to vary the pitch mid operations. Which means it's not going to be any good for applications at large scales.
Great vid and thanks. It's easy to be completely side-tracked by the ongoing battle for kW h/kg supremacy and forget that there are efficiencies to be made elsewhere (think Aptera). I wonder to what extent AI or other types of optimisation (genetic etc.) can be employed to move design towards optimal toroidal profiles for various applications. Cheers from Sydney _ Dave
Do you think it would be a challenge to build one out of carbon fiber at a larger scale? Looks like a great way to improve a paramotor's efficiency, but I'm already feeling the hole in my wallet 😂
Part of the issue with carbon fiber, alteast in the aviation world, is the lack of damage limits, aluminum in props is still very common due to its lower cost, and higher damage tolerances that allow the blades to be blended and have the damaged areas removed to prevent stress risers and crack formation which can be catastrophic.
This prop without a new material adds to much mass to a prop, however there have been large advances in drone props that could help and not hurt the bank as bad. For instance they added small winglets to the ends of props to reduce these same problems. It reduces the vortices as well as lessening sounds and increases efficiency slightly. The big question is however is the advantage worth the extra cost.
Thank you for the video. The elimination of blade tip cavitation is critical to a submarine remaining undetected by enemy navies. As a submarine veteran, I am interested in the reduction of the noise signature should a toroidal propeller be tested on nuclear powered submarines. With all of the money that has previously been spent by the U.S. Navy on super quiet propeller designs, it's amazing that this hasn't been thought of before, or perhaps it has.
Thank you all for watching and the interesting comments, here are some points to address the main ones I have seen:
- Great points about how this may be manufactured in the future, part of the economies of scale I mentioned could definitely include injection moulding or similar.
- Durability is an interesting point and I would love to see how the blades fair in a 'crash test', they may also be harder to repair? Let me know your thoughts.
- The gain in efficiency is 105% when compared to the original values (38% to 78%), it is true that absolute efficiency cannot be over 100%, but increases can be. Such as a company seeing a 200% increase in profits, for example.
- Many saying that reduced cavitation may also reduce wear on the blades, making them last longer in boats. Great point that I didn't think of!
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.
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.
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
Major props to the inventors.
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
Im a CNC programmer who worked for a top tier marine propulsion company for years. Our company has been in the R&D phase of producing a prop similar to this for years to no avail. We produce the Volvo-Penta dual out drive props and Volvo is/was very interested in this design.
The main hurdle we couldn't clear on this design was cavitation and vibration during high RPM, which absolutely destroys lower ends. We even consulted top level fluid dynamic phd's from University of Michigan and still haven't cracked the code (pun intended), as of 2019 anyways.
I had to work hand-in-hand with our engineers on this project and I can say with 100% certainty, these style prop's are a bear to machine, even using state of the art 5-axis mills, the tolerances are crazy and the balance has to be absolutely perfect to mitigate the issues I mentioned above. I've produced some highly technical stuff in my career, including Govt. projects like the Navy's SWS submersible troop transport vessel to high end Hatteras, Bertram and Bollinger Shipyard 5, 7 and 8 blade NiBrAl, Bronze and Stainless steel props for luxury yachts and cargo vessels alike. All that being said those projects were a cake walk in comparison to this design. I don't miss the stress, twisted steel & broken tools. I was on a 1st name basis with our Dapra tool rep after trying to machine these.
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.
@fladave99 Mills @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.
Well well well, we have an expert over here. Interesting stuff. So what's different now, why did the people in the video succeed where you guys failed?
I could see this being interesting for FPV, quieter at the same performance and potentially greater crash resistance with the right materials. Not to mention it would probably hurt a lot less to get hit by one of these props compared to an open blade
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 ;)
So exciting! My dad was a metallurgist and cast many large propellers for military, cargo, and passenger vessels. I wish he was still around so I could share this with him. Thank you!
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!
As a drone pilot, I love the idea of quieter flight & improved rfficiency! Hope these make it to the marketplace soon! 🙂
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
@K L 😂 okay
It's crazy how much improvement can be made to everything we already have.
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.
I love seeing engineering breakthroughs like this. Amazing stuff.
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
Being able to travel 20% farther with the same amount of fuel the boat can holy and doing it faster is quite an improvement.
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
Cavitation also is responsible for a great deal of wear and tear, shortening the service life of a propeller. Given that even smaller propellers aren't inexpensive, consider replacement costs on a cargo or military vessel.
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.
Back in the 70s I ran into this toroidal propeller design in patent reseach. While attempting to design a constant torque variable pitch propeller myself. Must say I was very impressed at the time. In my own study of the toroidal design I drew the same conclusion of machine shop limitations of this design in manufacturing on a commercial level. But an extremely viable concept since the invention of 3 axis cnc machinery on an industrial scale. The shape does redefine the term of warp speed,, due to the warping of edge chines in this design.
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.
“My intern did all the work and I won’t even say his name.” I’d expect nothing less
As someone who is looking to work on a bulk freighter on the Great Lakes, I would love to see these props tried on the large freighters. Hopefully they can make the ships even more efficient and comfortable for the crews.
Interlake is looking for people!
I imagine that toroidal blades could be amazing on fans, both for noise and static pressure
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.
@@flask9712 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.
Such a cool innovation with a surprising amount of applications! Hopefully they become more cost effective in the future!
I hope so!
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
It's HILARIOUS how the commercial before this vid starts with "Don't be fooled.." 😂
These are quieter, but they're far from more efficient.
Don't believe me? You will in a year or two.
They won't figure out how to make them as-efficient+maneuverable+ this much quieter for a long, long time, if ever.
Makes me curious a few things:
1) the electric Candela C-8 hydrofoil has an 80% fuel reduction once the hydrofoils are turned on. They use a counter rotating double prop configuration.
What would happen if they used a toroidal prop?
2) can & is there any benefit to using counter rotating toroidal props?
3) cab bionic propeller configurations be incorporated into a toroidal design? With any added benefits?
4) vs counter rotating, what if made longer? In less a HAWT design and more a VAWT design where they could run through multiple toroidal twists?
5) now make those longer/multiple toroidal twists counter rotating on the same shaft.
2:54 I think that it would be good to point out that the RPM at the bottom of this graph is the engine rpm. So in case of the Mercury 400 L6, (the V10 model has been out for so little time that I assume it's the old L6 model) which has a 1.75:1 gear ratio, the props are actually turning at ~2300rpm at the mentioned 4000rpm engine speed.
Love to see the effects on massive ships like cargo and cruises
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.
A couple of thoughts that pop into my head from this:
1. I hope all the numbers presented hold up!
2. I sure as hell hope this scales up for large cargo ships. More efficient and quieter, that would be amazing. Ships already outweigh all the fish in the seas iirc, so a change like this would have a HUGE impact.
3. That noise comparison? Now imagine those being electric motors. The noise difference adds up. Insane change for the better. Love it.
4. This reminds me of a video I saw showing a potential new main wing layout for airliners that NASA is thinking of funding large-scale testing. A wing shape that is basically this shape! The wing goes out, smooth curve upwards, goes back in again to attach to the plane further back.
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
This may be the biggest innovation I've seen in my lifetime.
The outboard boat motor have the exhaust coming out from the centre of the propeller, so there will always be bubbles there. If anyone was wondering.
Thank you
Or we can add second propeller which nullify centrifugal force.
4:47 I'd imagine the major drawback for larger aircraft is they require variable pitch props and rotary wings. But the concept is fascinating.
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
Unbelievably cool and useful. How did no one think of this earlier. It's amazing how we keep finding new improvements. I'm so excited for the future!
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
This is proof we still live with in a modern era despite how postmodern the world may seem. We are still inventing and growing our technology to this very day.
It would be interesting to see whether a variant of this would be suitable for use in energy production plants, such as wind farms or hydro electric dams
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!
It's amazing how the toroidal propeller draws the water in from surrounding areas as shown with the dye in the water test. It would be great to see more of them and more manufactured to bring down the cost.
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.
I hope that this sees wide scale adoption by many in the boat and aircraft industries. It looks really cool too. Thank you.
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
Fascinating topic and well presented - as a lifelong power boater I certainly love the idea of this so far untapped potential efficiency gain. And as someone involved in the emerging advanced/urban air mobility industry I’m interested in mitigating what will almost certainly be the impacts of community annoyance to noise. Subbed!
Very well done video. I’m in the aerospace industry and did some pretty intense research on these a few weeks ago… and you covered almost every point I looked into :) something interesting is that like you said, most large rotorcraft have slower spin speeds, but a neat exception is in the tail rotor of helicopters. They tend to spin pretty damn fast
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.
Propeller efficiency is also looked at the large scale. Adam Savage did visit Archer Aviation for a demonstration of their E-VTOL demonstrator. One engineer talked about propeller noise and how to reduce it with fluid dynamics simulation. It's all about vortex shedding and tip speed. Don't forget: airliners have jet engines which blade tips (of the main fan) go supersonic - this is why they are so damn loud... ✌️
Another example: CFM RISE, which is based on the research of the GE36 UDF (his was the engine for Boeing's planned 7J7 airliner). The RISE has special external blades and static blades directly behind them. All this is geared towards efficiency and noise reduction and will come to market within the next 6-8 years. 😎
The lower efficiency gain of the boat prop at lower rpms is probably because there’s little cavitation of the conventional prop at those speeds to begin with. Scale up the size though, and cavitation is a big problem for ships props, despite their low rpm,
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 :-)
Alot of people are failing to realize this design has to be mechanically perfect. More perfect than a piston in an engine and it's one solid peice
That's mad, always love me some efficiency. Hope these become the norm in the next 5-10 years!
Less of an issue than the other aspects in the majority of cases, but would be interested to know if they are less (or more) durability in the instance of hitting something.
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
I would also be interested in seeing how the new prop design does in the standard pontoon environment. I.E. weedy low water level areas. Seems like pulling up to the local sand bar for a couple beers and touching the prop on the sand at a low RPM would transfer significantly more torque load to the lower unit causing significantly more damage than you would have on a traditional prop. Very cool design though and glad to see innovation on a product that seems to be unchanged for so many years.
On a hovercraft
Since a few years back now ive been drawing propellers in this exact shape, but my gf always just finds em amusing. ”Looks simple enough, dont you think people would have made it already”.
Im happy to see it actually works! Cheers :)
More Efficient and quieter is amazing, great video!! Thanks
Dude, I love this video and your format. Just educational, no "remember to like and subscribe", no sponsors or ads. Thank you!
Fantastic explanation! Glad to find someone actually explaining the physics behind why they produce less noise and improve efficiency
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?
This is awesome, and the type of thing that needs to happen more: small incremental changes that yield gains in efficiency, but across more areas, would lead to massive gains across society.
a number of questions here for people curious about wind turbines:
- wind turbines already have enormous blades with manufacturing difficulties - would these compound with toroidal design manufacturing difficulties?
- wind turbines have much lower RPM than propellers - would there be any benefit? is there a similar efficiency graph for reynolds number?
- modern wind turbines often have variable blade pitch - how is this handled on toroidal propellers?
105% efficiency! You have discovered the secret of perpetual motion! Well done!
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.
Very impressive. I've often thought that drones could never be a viable means of transporting goods in a residential enviroment due to the insane amount of noise that standard propellers produce. This altered design completely changes my view of the whole concept now. It makes you wonder if this design could be incorporated somehow into jet engine turbine blades to increase thrust, reduce noise and gain fuel economy. Guess time will tell
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?
Could argue for a smaller (cheaper) outboard motor if fitted with these more expensive props. This could offset some of the cost while keeping the performance levels identical.
This is huge!hey hats off to you for being on top of this type of video, it's seriously a major saving of fuel and makes the boat for efficient through the water.thsnks for the vid.
I find this concept (now an actual working concept) quite fascinating. Thank you young man for educating me with your concise succint video presentation.
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?
On a ducted fan application, the results are comparable, but the noise reduction is still impressive.
Very Interesting, as ships engineer and Superintendent for very large vessels this would be something I would like to try out on one of my vessels.
Nice Suzuki bike and BMW car collection
@@HTV-2_Hypersonic_Glide_Vehicle Tks!
River but especially Lacustrine boat use has a huge environmental impact. This propeller should be a very high priority for study.
A shrouded fan (like you might find in a jet engine or computer fan application) doesn't produce tip vorticies. And, there may be an aerodynamic limit to its use in drones and as a main rotor of a helicopter because those applications demand the prop be moved laterally through the air, not parallel with the direction of travel. The blade going from advancing to retreating might suffer signficant drag at the 12 and 6 o'clock positions.
Fascinating stuff, the side by side sound comparison of the two boat props is a dramatic difference in sound level, I wonder if that holds true in the air, I'd be interested in hearing a side by side drone comparison. This has a wide range of applications; helicopters, fixed wing aircraft, shop fans, leaf blowers, hair dryers. The shape of recent submarine props are classified because our advisories could calculate the subs capabilities and at what sound frequencies they could track them, I wonder if another reason they are concealed from view is because they have a very unique design such as this. If so, this technology could have trickled down, been declassified, due to common knowledge by our advisories, I'm spitballing here but, it's possible.
@Theodore Olson 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?
Also imagine the sound difference when the camera/microphone is turned 180 degrees looking/listening towards the front of the boat. The wind noise from that perspective would probably mute anything else.
When talking about efficiencies and throwing in numbers like *+105%* you should always look at the definition of what they mean with efficiency in this case.
Because it is very easy to play around with these numbers.
Yep, I'm not even going to watch it because 105% is nonsense, so I assume most of the video is dubious too.
Just a suggestion that the golden ratio be utilized. The circle that is being utilized currently causes drag, the golden ratio will give it up more efficient cutting surface.
The following is a copy and paste from Wikipedia
In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities. Expressed algebraically, for quantities a and b with a > b > 0, {\displaystyle {\frac {a+b}{a}}={\frac {a}{b}}=\varphi } where the Greek letter phi denotes the golden ratio
Very interesting , compact and well presented , thank you ! Hope , that this invention gets soon into common usage !
Excellent, I can see them being applied to wind and hydro energy generation as well
Probably, but not likely. It work best on in high speed area.
These props have been around for years.. If they were that much better, many outboards would have them... I think the problem is at the tip of the prop there is a area that produces no lift, but does add drag as the tips are going the fastest. This can be done with a reg prop with washout, but if that worked all props would have that too.
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?
One of the most fascinating things about this is that it can be retrofitted to just about anything. As soon as the manufacturing reaches reasonable scale you relatively inexpensively put it into any system (as opposed to putting in a new engine for example) I look forward to seeing this tried at a larger scale to see if the increased scaling of weight (for example a full size helicopter blade) would negatively impact effectiveness. The other portion of this that I'm unfamiliar with is how does this system load, helicopter blades flex rather extensively right now and if this shape isn't able to do that and is therefore going to require it to be more built out certain applications might be ineffective.
This is one of those discoveries that makes me scratch my head about how much sooner we might have been able to achieve certain things if we had known about it from the outset
i think that helicopters change the pitch/attack angle of individual blades so probably it wouldn't work out
Having retired from Aviation after 30 years I have gained a lot of knowledge in the efficiency of propellers. The biggest difference I see is that the tip of a standard propeller actually breaks the sound barrier, that is typically what makes the most noise and also causes drag and reduces propulsion at the tip. The circular design eliminates the tip of the propeller, making it much more quiet and much more efficient.
I was messing around in my pc this morning and watching the fans spin and thinking how they cause all the noise - this is 100% going to be in every small cooling fan in the world soon. Thanks 😊
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:
th-cam.com/video/4ImeOKgD_Dw/w-d-xo.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
This would be an absolute game changer for heavyfuel-using vessels. The 7 biggest container ships produce more sulfur than every car in Britain per year.
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)
FYI: Efficiency over 100% isn't free energy or perpetual motion. It uses existing energy from the environment, possibly with effects like localized cooling occuring. Heat pumps are a great example of this. Its how you define efficiency.
WOW... real practical information about innovation. GREAT video, Sir. This is a real change. Even as a personal boater, the lower noise profile alone would be worth the cost. As a commercial application, the economy over time makes the initial cost negligible. I have a hard time understanding why this won't become standard within a decade.
Quality video on a genuinely interesting topic, no annoying adverts or click bait, great work man! 👍
I was amazed at the difference in noise levels between the outboards. Would never have guessed the prop made that much difference
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.
Use this great propeller on an electric boat, no more noise, very high efficiency. This could be the breakthrough for manned drone flight, such a natural idea, brilliant.
I'm curious if the improvements are limited to certain rpms or of they are present throughout the rpm range. As well it would be interesting to see how these props respond to being used in a ducted environment. Even in an azopod installing... gets the mind going So many additional, and fun, tests still to be done.
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.
Thank you for this great little video I had never seen these propellers before. I hope to see more drones using them in the future due to the significant reduction of noise and the increased efficiency which should also lead to an increase in flight time.
I would like to second that. A very interesting video.
Congratulations.. youve just achieved what no physicist has been about to do, no CERN scientist, not even Tesla himself : deliver a machine 100% efficient. You even went BEYOND 100% efficient, meaning youve achieved the impossible: a device that makes more energy than it consumes. All with a grinder and cardboard. WELL DONE!!
As a boat owner, I find this extremely interesting. As someone who is broke, I heard the price and lost all hope. Maybe someday, but not now or anytime soon.
Wonder how you'd manage to make the pitch variable for aircraft?
As others have pointed out, Variable pitch propellers are essentially standard for larger applications (both marine shipping and larger manned aircraft). I'm curious if theres even a possibility to make variable pitch toroidal props. I also wonder if the toroidal propellers would stand up to the increased centripital forces that come from increased diameter. Even if a Toroidal Helicopter rotor would stay in one piece, would it manage to keep its shape enough to retain the benefits?
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.
2:54
Deserves a video from some skeptical engineer channel. Sure, +105% efficiency!
On a cherry-picked range.
No, this doesn't mean that toroidal props are double the efficiency. It means their peak efficiency range is wider. The props are really only 8% more efficient. Which is still good, but that basically means toroidal props are ducted fans in disguise. With less problems than ducted, maybe. Remains to be seen.
The only negative I can see in boating applications is when the prop gets damaged. A conventional prop may get a major knick in it, but it's performance might not drastically affected. I just wonder if the thinner wall and lack of filler material would cause an issue
Stuff like this makes me really want a 3D printer - I would love to try to make props for my mavic 3 based on this.
3d printers are affordable nowadays, I picked one up under 300
If only I had time to use the damn thing lol
As a person with a home recording studio, the computer application for this is something I hope happens. We always have to keep the computer out of the room, or record outside the room.
why would you not just use background noise cancellation from a audio sample of your computer fans? or just use fan software to min the fan rpms when recording?
You might want to invest in a water cooling kit for your computer. There are off-the-shelf ones as well as custom water block kits. Not only is your computer cooler - but much quieter.
Cool video. Great info, articulated concisely. Nice work 👍🏻
It addresses an significant inefficiency in propellers, the "leakage" of fluid from the high pressure side to the low pressure side. It is this leakage that produces tip vortices. Commercial Jet Engines use the stator duct to prevent these "leaks" while high aspect ratio blades are used to minimise them. These toroidal blades avoid having tips, reducing the opportunity for "leaks". A very good idea! Hope it succeeds at an affordable price.
So far I've only seen the Sharrow props tested on relatively high speed outboard engines. On those engines, if you look at the low RPM range (under 3000RPM) the Sharrow doesn't give that _much_ of an improvement, not enough to justify the cost at least in my mind. Large cargo ships rarely run at over 2000 RPM, if that high, so it's doubtful if that prop design would give any benefit to shipping industry. That said, I would love to see a Sharrow type prop tested on a trawler type vessel rather than a "go-fast", just to see if it would give those same (small) increases in fuel economy.
.
As an aside, the concept behind the toroidal props isn't that new. You can safely wager that the various navies around the world have looked at using them on warships, especially on submarines where cavitation noise is the main cause of being detected. Another item, most marine props are CNC machined, especially performance outboard props. Large ship props are cast and then polished to the final shape.
I would expect that the efficiency versus speed curve would also be massively shifted depending on the dimensions of the propeller under test. Large conventional ship propellers already operate at vastly different speeds to propellers on outboard motors, for example.
Definitely an exciting design, but it seems there is one advantage the standard props have over the toroidal, that being standard probs have the ability to change their pitch. Most cargo ships don’t use azipod thrusters so instead they have controllable pitch props. Seems like a huge design challenge to implement toroidal props on ships that utilize controllable pitch
I’ve been doing some research and it’s actually not that hard
I am very curious about the stability and reliability of it in the long term. This could be one of the mayor factors in the future for this project.
Considering the blades are a loop, I don't think there's anything to worry about. I'll wager we'll less prop fouling as well.
major*
@@aurelia8028 everyone knows what he meant Einstein.
Definitely going to be less bending and fatigue with that shape than a free end hanging blade
Less noise means less drag and burning less fuel.
It was a great video, weldone.
Great quality content, no fluff, no bs. Good job!
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.
I wonder if that shape could work on turbocharged engines. Like pulling/pushing more air in to the cylinders or to work with lower emissions at lower RPM's?
Turbochargers would be using them if it were more efficient
How this can have efficiency over 100% not to mention +105%
Would be insanely difficult to get this to work on helicopters though. I mean the Kaman K-Max uses ailerons to change the pitch of the blades for lift so if you could mount these on a horizontal shaft with a pitch horn it might be possible but I think the torque over moving all that drag producing surface would not make it feasible.
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.
Great presentation on an awesome development! I could definitely see this being used in the future
I feel like ring propellers or ducted props would work as well as the toroidal prop for reducing tip vortices, but without the drawbacks of toroidal.
When we run out of oil, those propellers will come in handy for hauling all those massive batteries.
Toroidal design may be the tip of the iceberg when it comes to quieter, more powerful, efficient propellers. You're making headway, mates, keep working at it.
Just think if we use this in an submarine
I want to see this get used on ships, not just boats. That's when you can tell if it will change transport or not. We will see what is happening.
submarines ?
@@michaellorenzen8200if it produces less cavitation, thus less noise, every military submarine will use these in the future.
Seems so simple, but the results are incredible! Also, have you looked into putting your content on Nebula? I'd love to be able to support your channel even more by watching your videos on there.
You mentioned cavitation bubbles but missed mentioning the amount of damage they do to the propeller. Cavitation bubbles not only decrees efficiency but also damages the propeller, like allot. Just google propeller damage + cavitation bubbles, and you'll see what i mean. Thus, if this design reduces cavitation bubbles the durability of propellers will greatly increase, larger ship propellers are very effected by this as well, so lets hope this design is scalable!
Helicopter with this tech? Subs can definitely be expected to have these equipped sometime in the future.
@Professor Frog Thanks for the info. Still hope to see this tech make a visible change to things. Give things a more futuristic look while still being practical lol.
@Professor Frog Couldn't you implement this on an aircraft that is designed like the Osprey?
@@Propane_Acccessories The Osprey also uses variable pitch, it is effectively a helicopter for vertical takeoff/hover/etc anyway.
Similarly seemingly most planes also use variable pitch props.
I'm wondering if this blade design could be useful for wind turbines, or not. Probably not due to their angle of attack variations depending on wind speed.
They might, but, just like the existing ones, they won't turn when not windy!!!!!!!
@@ianharvey3696 Haha, true!
I bet they could use them. The angle of attack could still be adjusted but the adjustment would have to take place at where the prop joins the shaft meaning a total redesign. Likely worth it though.
Great to know there are absolutely no drawbacks! Hopefully they can reinvent the wheel next!
Actually there is one MASSIVE drawback. As far as I can tell there is no way to vary the pitch mid operations. Which means it's not going to be any good for applications at large scales.
We need more innovation like this.
Great vid and thanks. It's easy to be completely side-tracked by the ongoing battle for kW h/kg supremacy and forget that there are efficiencies to be made elsewhere (think Aptera). I wonder to what extent AI or other types of optimisation (genetic etc.) can be employed to move design towards optimal toroidal profiles for various applications. Cheers from Sydney _ Dave
Could this enhance the effectivity of wind turbines?
No. Surface area is important
Do you think it would be a challenge to build one out of carbon fiber at a larger scale? Looks like a great way to improve a paramotor's efficiency, but I'm already feeling the hole in my wallet 😂
You know that would be awesome, a lightweight prop in general would increase power and that new shape would make it amazing
Part of the issue with carbon fiber, alteast in the aviation world, is the lack of damage limits, aluminum in props is still very common due to its lower cost, and higher damage tolerances that allow the blades to be blended and have the damaged areas removed to prevent stress risers and crack formation which can be catastrophic.
This prop without a new material adds to much mass to a prop, however there have been large advances in drone props that could help and not hurt the bank as bad. For instance they added small winglets to the ends of props to reduce these same problems. It reduces the vortices as well as lessening sounds and increases efficiency slightly. The big question is however is the advantage worth the extra cost.
Thank you for the video. The elimination of blade tip cavitation is critical to a submarine remaining undetected by enemy navies. As a submarine veteran, I am interested in the reduction of the noise signature should a toroidal propeller be tested on nuclear powered submarines. With all of the money that has previously been spent by the U.S. Navy on super quiet propeller designs, it's amazing that this hasn't been thought of before, or perhaps it has.