Testing 12 Ultra Efficient Electric Boat Propellers

[@Freytraz]

The only reason I don't submit a propeller that would absolutely humiliate all other entries is that I don't understand propellers, have no knowledge of fluid dynamics, have a beginner-level capacity on modelling and don't know enough maths to learn it all in a short period. Thinking again, that's 5 reasons.

[@eckiger4566]

Yeah same otherwise i would

[@GoldenCroc]

Dont sell yourself short, your ability to count could be another reason as well, truly making it 5 reasons!😁

[@TylerBischoff]

I think you guys should give it a shot you might just be end making it but accident

[@395leandro]

Fair enough. I myself could just make one that's nearly 100% efficient, if not for the same reasons.

[@eckiger4566]

@@TylerBischoff yeah i think i should try like you said i would create an accident

[@GuilhermeLPC]

This is MajorHardware's PC fan competition but for RC hobby nerds, love it

[@emily36130]

Except this is much more scientific

[@Litl_Skitl]

Now we just need Integza to make a rocket nozzle competition

[@ssj3gohan456]

but with like... 4 sponsor spots in the video :P

[@ThreeAngrySquirrels]

I would love to see that crossover.

[@ser_igel]

@@ssj3gohan456 sponsorblock

[@Tyr1001]

the Race to Alaska just started yesterday. It might be something interesting for you to do next year, designing a droneship that can make it the whole way

[@zachogdahl210]

That would be a killer project. Put a gps tracker on it so we can watch its progress

[@mikehensley78]

Where do they race from!?

[@jonathancorbett5917]

Is it just called "the race to alaska" I need to know.

[@zachogdahl210]

@mikehensley78 port townsend WA to Ketchikan. Any boat can be used as long as it doesn't have an engine. Yes its called race to alaska. There is a documentary on it

[@mikehensley78]

@@zachogdahl210 that's awesome.

[@jamesm6830]

Love this! Small thing, the new graph is really useful but the colors of each prop change each time you showed it which made it hard to compare props.

[@Jinguapingi]

Wanted to say the same thing. I'd say it's the only negative thing of this video! If that's fixed in the next one, then it'll be awesome!!

[@timderks5960]

Yes, that really wasn't great. The all lower case and .txt descriptions on the side didn't really help either, especially since the names moved around too.

[@Tarrandus]

This also was an issue for me

[@OptimusMatrix]

Came here for this reply. Great video, keep the colors the same. It would be much easier to follow in the given time the images are shown on screen.

[@KarmaCadet]

they are labeled, but consistent colors would improve readability

[@Flesh_Wizard]

Spanmaxxing has got to be one of the most aesthetically pleasing propellers I've ever seen

[@AnyBodyWannaPeanut]

It's like looksmaxxing, but for propellers, that's why. 🤣

[@blaircox1589]

And very similar in appearance to a Power Prop for Minn Kota trolling motors.

[@cgsrtkzsytriul]

Nah whaleotron wins!

[@noyza2132]

like the sr71, it works because it looks fast

[@Madvizion]

After consuming so much trash media, i look so forward to awesome meaningful videos like this. Keep it up you are saving minds every where

[@carlwheezerofsouls3273]

this is the medicine that heals the tiktok brainrot

[@andrewzhan5207]

the type of content that make you think, instead of haha it funny

[@TheBoss_4151]

So refreshing to see actual science.

[@misfitking_0143]

I have to agree! If the content doesn't Edify, it makes you Foolish...

[@alskjflaksjdflakjdf]

Man, I am absolutely loving this series. Thanks for putting it on and spending so much time on it!

[@samuelmeis4669]

Excellent work, man! Many thanks!

[@rctestflight]

Thanks for your support!!!!

[@dannywastaken]

This is just the right ratio of video and pretty graphs. That editing balancing act is as impressive as the props. Well done Daniel!

[@pieman2656]

All props to you bud, this stuff is beyond me / over my head. Been watching your videos for years your parents must be proud, decent kid curious how things work and then try make them better while enjoying life. Keep the projects coming I will get my head around it some day, heck I don't have a 3D printer or do CAD but you have a gut feel what will work. Amazing designs keep them coming.

[@hyperverbal]

Spanmaxing was tight ❤

[@_zzpza]

Barely an inconvenience.... sorry wrong channel.

[@sorendumar1958]

On the contrary, it was quite wide

[@GoldenCroc]

@@sorendumar1958 Us professionals like to call it "width-y". Its a technical term.

[@davidf2281]

Wow wow wow. Wow.

[@sorendumar1958]

@@GoldenCroc Oh, I see.

[@maca5645]

I have never designed a prop, owned an RC anything or 3D printer. But as an airline pilot and wing and surf foiler i had to watch the whole thing.Fascinating. Vids like this restore my faith in humanity ,thx!.

[@veizour]

Congrats to Spanmaxxing for current first place! Very neat project.

[@LongerThanAverageUsername]

Holy camera quality!

[@kylethatcher5828]

Great video, as always! I just want to say that your brand integration is the best out there. You made meaningful plugs for several companies and they were all appropriate and didn’t feel forced at all. I hope it’s beneficial for both parties, and I hope it results in more amazing content in the future.

[@JoeJJohnsonII85]

Some of the names for these props are amazing. Forever alone takes a special top spot for me.

[@sikhswim]

This is by far the most exciting competition I’ve ever seen on KZbin!!! Can’t wait for s1s3

[@kitewinds663]

Tack!

[@wessonw2-td7kh]

Mad props to this series! I enjoy the community involvement element! It is incredible how technology has opened doors to design, share ideas and collaborate. Huge potential for innovation from this format.

[@itsjustmeBryan]

I'm not an engineer or anything, i just like watching people make stuff and test them. it's cool that you give resources for other people to try out

[@andydelarue9344]

Wow thank you for the best smartest competition online, It’s a pure joy to listen, watch and see competitors wild great ideas run thur your test bed. Don’t stop now this is great

[@boppins]

This is a fun series, and I don't even boat! I love your explanations and how you don't just toss away design ideas, but rather explain how they could improve or maybe some other factor is limiting them. Definitely should include details on the motor for your next competition - looking forward to it!

[@blackturbine]

Being really busy and having hardware issues I was pleasantly suprised that you actually tested it even though I was really late I'm really sorry about that. I couldn't give it proper cfd analysis so I had to go with "trust me bro" airfoils so the fact it was even close to baseline is amazing, thank you for detailed analysis and I'll try to make a better version and see if it can make a comeback. Let the best propeller win ^^

[@chemicalcorrosion]

Quite the rabbit hole you’re going down here. Can’t wait to see where it leads!!

[@ryanjohnson3615]

Excited for the variable pitch prop we got a quick glimpse of @23:49 !

[@highonpcbs]

I can attest for the efficiency of the PROPELDERT. I am from the solar team in the video, Solar Team Sneek. This design is indeed used with the boat shown and the most efficient speed for the boat is about > 20kmh. That explains why it doesn't work well with the motor used. It just needs a bit more power. If i remember correctly we use less than 2 kWatts at that speed.

[@williamfraser]

Is there a diameter limit on the props used for the solar boats?

[@highonpcbs]

@@williamfraser no, we are completely free in the design. But for practical reasons there is limit(also on the power of the motor), for example we have a sprint prop. but it can only be used if we are able to fly on hydrofoils, otherwise the torque of the motor isnt enough. So the prop shown is designed to match with the motor to operate in its efficient rpm range. There are even teams that dont have the knowledge we have and use a standard torqeedo prop/standard boat prop.

[@andrewnguyen6846]

"that looks about right" sounds about right to me!

[@aserta]

Using that method to figure out the prop is almost like divination. I like it tho. You start with an idea, you wild it out. You test both. You pull conclusions, you figure two new models (or more) you test them all out. You plot the chart. You pull new conclusions, new models, new tests, rinse and repeat. So as long as you remain within the OG parameters, you can do this until you've reached the thin line between ideal and impossibly good.

[@TheLoneWolfling]

...assuming that there are no local optima.

[@EversonBernardes]

@@TheLoneWolfling that's why for genetic algorithms you usually add a few vastly different new entrants with each generation, so you're much less likely to get stuck in a local optimum. If you're doing 16 specimens, you keep 4 best from the previous gen, 4 new entrants and 8 offsprings with random mutations.

[@TheLoneWolfling]

@@EversonBernardes Yep. That can work, assuming the function you're optimizing is well-behaved. However, that's not my point. My point is the the original comment is not correct in a fairly common case.

[@joshuagibson2520]

This is great. It gives me hope to see young people doing these kinds of things.

[@CarlosAlberto-rt6jv]

I would love a series of this. Getting to see different designers' product and their thinking when designing is the best content on youtube in so long

[@Will-qm1id]

borrrrrrring

[@locouk]

Daniel, I got no 3D printer or boat BUT… This propeller series is absolutely awesome! 10/10, I hope you “crowd source” an amazing efficient design that changes the industry.

[@GoldenCroc]

I like your optimism, but thats not going to happen. I should think prop science is pretty darn well understood.

[@julianbrelsford]

@locouk - i was intrigued by how, in this application, the propellers seemed to apply principles that also work in glider aircraft: longer span, higher aspect ratio, and a lack of corners tended to give excellent efficiency

[@dawall3732]

11:35 What is going on at the tip of that propeller's blades? Is that an optical illusion, or are they heating up?

[@danilopmaciel]

For a better view, a table at the end of the video with the propellers with the best performance would be nice. Thanks for the video. Very good.

[@johnmcfadden9336]

I don’t have time or resources to engage in this activity but I really like this channel, thanks to this community 😃

[@starsportscards8688]

Prop till you drop!

[@powerhouse109]

No plane, no gain

[@CioerKieov]

Well done on this series! The part about community involvement is fun! It's amazing how technology has made it possible to cooperate, share ideas, and design. This format has a ton of innovative potential.

[@ThreeAngrySquirrels]

I think their argument was that manta rays have a winglet like tip geometry during their power stroke which is what the propellor is doing continuously. The propellor doesn't need to reset itself for the next stroke, but the ray does so it's floppy.

[@merekcook573]

*Props* to the Palnovic propeller guy There's nothing wrong with being confident and ending up wrong, important thing is he fixed some of the things wrong and tried again I think that's really cool :>

[@weatheranddarkness]

Forever Alone (2) really seems to have some real potential. Very clean in the slo-mo and a high top speed, and really close in efficiency to the winner.

[@Simple_Woodcraft]

I saw on discord that forever alone was like three thousandths of an inch over the size limit.... hardly matters especially if it's faster.

[@PatrickHoodDaniel]

17:50 I think that is called finding the global or local minimum which is used in backpropagation to determine error reduction with gradient descent in artificial neural networks (or other ML algorithm) and other derivative based calculations. It's interesting to use this with props in a similar way and I wonder if ANN would be able to find a better solution.

[@voidvoidvoid7274]

Dealing with fluid dynamics is one hell of a challenge, especially if you only know the basics... GG to everyone who submitted their designs tho, you people are insane and even if your designs were not the best, at least you tried. This is how we, as a species progress, through trial and error.

[@stevemaricar4350]

Intriguing designs and impressive simulations in the competition. The performance of Span Maxing outdid expectations.

[@wiresmith2398]

The [REDACTED] project with that ESP32 next to the STM32 looks pretty neat - can't wait to see a video about [REDACTED] [REDACTING] with an RF [INFORMATION REMOVED BY MINISTRY OF THINGIES]

[@Bare_Essence]

You changed the colors mid-video. I was very confused when I skipped near the end :) That's one way of making people watch the whole file. Nice job!

[@hankhulator5007]

Hi, super and useful series as nothing's better than experimentation. Also funny, because it shows how we can be biased when estimating visually the efficiency of a propeller.

[@rothn2]

As an ML person, the parametric one checks out. I was wondering how something like that would perform for the whole first part of the video! Posting before I see the results-- glad you included this one!

[@Davidus053]

Wake up babe, new rctestflight video just dropped!!

[@AnonNomad]

babe it's 3am

[@extremechimpout]

I'm your mother for the last time stop calling me babe

[@Strataos_]

Slowly becoming rctestswim

[@Strataos_]

I did not see the first prop when i put that

[@Strataos_]

@@MrHardzio4Fun no i just started the video

[@brianperkins3437]

I'm really impressed with the time and attention to detail you put into this project. All of the testing and printing and redesigning of the test vehicle must have been really time consuming. You could have easily made this into yet another KZbin stunt. I really respect you for not doing that.

[@mikehensley78]

I been waiting on episode 2! Hell yeah.

[@ala068]

I would not worry about "not going to school" with the type of Projects you are entertaining... Great work with solid theoretically & foundation! Keep it up and looking forward to season 2.

[@TheoriginalQward]

Hurray! new episode! Cant wait for the self guided submarine.

[@ThePrimaFacie]

There is so much really cool info (more then usual which is saying something) in this vid. I really like how so many people tried their ideas out then you giving an explanation of the hows and whys. Thanks for the vid and to everyone that tried out.

[@ihikefar]

Consider adding a dye stream to test and visualize flow. Bubbles have buoyancy and are not an optimal indicator.

[@fredio54]

This mini series has to be some of my favourite videos of yours. Thank yohbso much for all the effort, all the time building the cad and finite element analysis and manufacturing relationships, and the concept itself. Thanks also to all the people and orga that submitted designs. This is wonderful.

[@calebcaetano1863]

These are the best videos on KZbin, keep it up.

[@stephenhammond1656]

Thank you, I could watch you test stuff all day, very scientific, very interesting. Love your work. Cheers.

[@samlentz6011]

Bonus props were great

[@JoaoAntonioCardoso]

Awesome!!

[@rctestflight]

Thanks for your support!!!!

[@sorendumar1958]

EPISODE TWO BABEHHH!!!!!!

[@HealthyNugs]

I love this! it's a great example of collaborative development creating divergent design ideas that a solo developer would miss or dismiss.

[@santaclaus0815]

Finding out the efficiency curve of an electric motor by testing is actually quite simple: you take 3 motors. Test 1: Motor 1 drives, motor 2 serves as a generator and drives a light bulb, for example. By measuring the currents and voltages, you get an equation for the power currents. But it contains 2 unknowns, namely the efficiencies of motors 1 and 2. Test 2: Carry out test 1 with motors 2 and 3. Test 3: Carry out test 1 with motors 3 and 1. Tests 4-6: Carry out tests 1-3 by swapping the motor and generator roles. Now you have 6 unknowns (one efficiency for generator role and one for motor role per machine) but also 6 equations (because you made 6 tests) and can thus calculate the individual efficiencies. Torque and speed should of course be identical in all tests.

[@adolfvalasek7810]

You could just use 2 identical motors and be fine with just one test, assuming their efficiency is the same

[@Snail_With_a_Shotgun]

I think your way is needlessly complicated, still. You can just grab a motor, attach a flywheel to it, and spin it up while collecting telemetry like RPM, Volts and Amps in. Measuring RPM over time will allow you to find the torque at each RPM to get a torque curve, multiplying said torque by RPM will net you the power output for a power curve, and dividing that by power input should give you the efficiency curve.

[@santaclaus0815]

@@adolfvalasek7810 no you can't because you can't be sure whether the efficiency in motor mode and generator mode are the same.

[@santaclaus0815]

@@Snail_With_a_Shotgun You are right. But you must know the rotational inertia of that flywheel and that of the motor's rotor too. and that is a not a steady but transient process. the time step of the measurement must be small enough to get a good reading of the acceleration. points in time of all measured variables must be identical.

[@Snail_With_a_Shotgun]

@@santaclaus0815 Finding the inertia is trivial, though. I=m*r^2. And the need of time step to be small is something sensor manufacturers are acutely aware of, and so sensors are made with exactly that in mind. Ultimately, all issues can be solved simply by using a flywheel with a sufficiently high inertia, which will reduce the sensor frequency needed, as well as reduce the impact of unknown and unaccounted for variables and improve the accuracy of the measurement.

[@roberthoffman4713]

This is the second video of yours, on propellers that I have watched. I must say there's a bunch more science involved than I ever would have thought of. I find it very interesting. The only prior experience I have with propellers is from one of my past jobs we needed a boat to patrol under a bridge we were working on. I only really learned the very basics on how the pitch of the propeller affected the speed vs torque on the boat that we had and that the one propeller would drag heavy loads but could barely move the boat up stream and the other propeller had more speed but couldn't pull stuff very well. Now I am learning much more than I ever thought there was to know.

[@scottcates]

I'm very curious to see how/if a spinning, ducted fan compares to a toroidal design because they share some similarities.

[@nerd1000ify]

Ducted props (aka Kort Nozzles) are pretty common on tugboats and trawlers. They're optimal if you need to put a lot of power down at low speed and are limited on diameter, which is the case for those boats because they also need a reasonably shallow draft (depth of the lowest part of the boat). As you go faster the additional drag of the duct tends to outweigh the efficiency gain.

[@BloodyMobile]

23:42 that shot right before the boat turns is great, you can clearly see 3 different waves it's creating, each at a different angle.

[@olegladizhensky9379]

Just amazing. One person makes a job of entire scientific institute just by calling to the world for propeller designs.

[@bwmcelya]

As a weekend boater, I find this all fascinating. One day I’ll be able to buy a super-expensive prop that takes me 2mph faster. Thanks for all that research and testing. It’s how we humans make progress, one small step at a time.

[@richardhamilton-gibbs6360]

"I don't really know. I didn't go to school." Love it! School only takes you so far. 1% inspiration, 99% preparation is real life!

[@bulldog370a]

As a high school English teacher, I'd like to say, "Maybe he meant that he didn't go to college, because he most certainly went to school."

[@bulldog370a]

He most definitely went to school. I think he meant he didn't go to college.

[@typxxilps]

great one ! I like this competition and your explanations and watched it to the end. Even the spnsor looked good and fit quite well - for me, far better than all the food stuff.

[@lepidoptera9337]

I don't think you are testing actual prop efficiency here. You are mostly testing how well your props are matched to your motor and by accident the best performing prop was close to the optimum. But then you basically kept saying that yourself. It just shows how non-trivial a problem this test is...

[@MrSchrodingersCat01]

Please correct me if I am wrong, but yeah I think there may be subtle error here. Torque * RPM = Power, but that would be the power at the shaft. He’s measuring the electrical input power rather than the power at the shaft. There would need to be an external control loop around the ESC which would take shaft torque and RPM as inputs and then adjust the ESC to achieve a set shaft power. It’s still a very impressive setup and it’s super awesome regardless of this. The results are still all accurate relative to each other with the caveat of only being valid for that specific motor part number.

[@lepidoptera9337]

@@MrSchrodingersCat01 I don't know much about propeller design but I believe to remember that efficiency is RPM dependent (hence the need for variable pitch propellers in aviation). For a commercial vessel the speed is probably set in a tight range that is most economical for international shipping, so the entire propulsive system is designed for that constant speed. Not sure what the actual design requirement is for a model boat or, if we scale this up, for a small personal watercraft.

[@TheMrBrendo]

I dont know anything about propellers but i am hooked on this series!

[@TravelingDude420]

I love watching this, nodding along as if I understand anything more than the superficial ideas being communicated. It's really fascinating to watch some math get hardcore

[@olegladizhensky9379]

There is one ancient vibration test used on metal working machines like lathes: put a coin on a rib. If it stays still, then your level of vibration is ok, if it "walks" or falls- something is wrong. Probably similar approach may be used to test propellers.

[@SpeedyGwen]

this is amazing, tho I would Absolutely love a third contest and with actual numbers about the motor, am sure people could cook up some absolutely amazing designs !

[@runescapebanker]

Dude. This is awesome. So well done. Can't wait to watch the final.

[@wiredforstereo]

Trail Tracer Receiver Board, wonder what that could be.

[@ausieking]

Flight controller?

[@wiredforstereo]

@@ausieking If i had to guess, I'd say it's a controller for his tracked vehicle or some other new vehicle we haven't seen yet.

[@AkaraVortex]

Absolutely love the idea behind Whaletron, and what pleases me the most that it is most efficient and fast outside of high-ratio ones.

[@amos9274]

Hey, I think switching from g/W to efficiency % and then averaging it would be really helpful. You just have to multiply it by the velocity and the graphs become just that much more intuitive :)

[@darthkarl99]

The other option for future competitions if you do somthing like this would be to create a CVT for the motor and a computer control software than can monitor the motor RPM and current draw and use that against the efficiency curve to figure out weather to adjust the gear ratio to raise or lower motor torque required. That give people more room to play outside of one optimised torque value, (which for a given maximum allowable power draw also means one ideal peak RPM, which really constrains the propeller design).

[@shmeblord]

LETS GOOOOOO!!!

[@peperoni_pepino]

You can tell this channel is becoming popular in the Netherlands, lol: 1. People complained about 'Wageningen' being pronounced wrong. (I'm guilty!) 2. Someone called Loek (and a name with 'van', can't find it again and can't recall the last name). 3. Someone called Eldert Zeinstra talking about solar-powered race boats.

[@mitchib1440]

Paunovic lol. Better than last time but still not great. Dunning Kruger effect strikes again.

[@snowe..]

Anyone claiming they will “revolutionize” literally anything is just trying to sell you something or they’re ignorant. In this case since they keep calling it “patent pending” it’s the first.

[@ed8212]

Id be interested to know what the actual intended application for that thing is, and how well it does in it

[@vmaru96]

@@ed8212 On their website they list it for drone applications. They also show some graphs that seem to show efficiency improvements over six-bladed designs, but never compare it to traditional three-bladed designs.

[@doc294]

In the video, you said you didn't go to school. I have to say your scientific approach to all of this is incredible. Also, the subject matter is incredibly interesting.

[@AndrewJohnson-oy8oj]

One takeaway: Our industry standard is so inefficient that there are dozens of ways to produce better, but we'll keep using it. A study in the sunk cost fallacy.

[@marlinnotfish]

You didn’t go to school? Was that sarcasm because I thought for sure you have a degree in engineering or something like that? Besides stuff built here, you are the smartest KZbinr I watch. Props to you.

[@mitchib1440]

I really don't think Paunovic should've been featured again. Kinda unfair that he gets two tries but everyone else gets one. He didn't listen to you at first, got proven wrong and failed spectacularly, and only then decided to make an effort and resubmit. Poor showing imho

[@shea8830]

I’d like to see airshape give it another shot

[@32BitJunkie]

I'd prefer he give 2nd and 3rd tries to anyone who wants them. The point of this experiment is to learn what sorts of propellers work well. I could care less who gets prizes

[@nathanguyon7620]

Yeah, but we get a chuckle twice this way.

[@mitchib1440]

@@nathanguyon7620 LMAO can't argue with you there

[@RCake]

Brilliant series - thank you so much for doing this and documenting it so well for us 🤩😍🤩

[@theovannieuwenhuizen5756]

I just love your excellent story telling and science. Can't wait for the next episode. Best, the Netherlands.

[@highpointsights]

Very well done!! My guess is that when you are done, you'll be able to approximate the functional values by observation!! Your brain will do the sims on it's own!!!

[@willgilliam9053]

Entire video was awesome.... Watching the prop stop the boat at the end... pretty cool

[@6root91]

Why is this as entertaining to watch as those reality shows, designed to keep people hooked, despite lacking much substance.

[@alfredspijkerman]

Really cool. This is also interesting for real boat props. Generally high aspect and large diameter gives the highest efficiency. However with practical full scale designs there is almost always a maximum diameter.

[@nathanhumke]

Dude you rock please don’t stop! Actually if you could please throw out a.” I IANt EVER GNAW STOP” William Montgomery

[@5peciesunkn0wn]

and another fun round~ Can't wait to see what bonkers designs show up in the third set!

[@dwahnaslowdown8887]

That was a LOT of work. Kudos.

[@pilotnamealreadytaken6035]

I wonder when the us navy comes and knocks on his door. ❤ Great content, this was my first view of this channel. Fantastic production quality! Good luck with future content!

[@fallenangel3k]

your videos of testing so many propellers are very precious to the community. this gives the "average men" a very good clue about what happens if you change this and that. only would love to see a similar video where you testing propellers for drones in a similar manner.

[@fallenangel3k]

yet speaking this topic; show what is a true pro-peller and a true re-peller; then show the difference between medium air and medium water and what it means to the shapes, thickness, attackangles, etc... pleeaaaasse

[@thomasfisher1829]

You can tell it's efficient because of the way it is! that's pretty neat!

[@taokodr]

This showed up in my side feed while I was watching another video. Checked it out, and you have a subscriber! This is some truly interesting stuff! :)

[@michaelenglund]

”I don’t know. I didn’t go to school” You can really be an inspiration to those that didnt perform in school as society expected as you do advanced and cool stuff 😎

[@maudesu.]

I love this content. An engineering showdown !!