That under water footage is amazing, props for taking this much time to create a video.

@apacheandy

25 күн бұрын

Pun intended...? :D

@praveenb9048

25 күн бұрын

​@@apacheandyyou beat me to it

@plarkmoby

25 күн бұрын

I nearly clicked away and had to come back. Wonderful pun, bravo.

@rosiepone

24 күн бұрын

props, haha

@marcd5132

24 күн бұрын

props 😎

I like how you absolutely shat on the guy with his 'patent pending' prop and absurdly high confidence, and then immediately proved your point. Insane how people just refuse to take feedback

@viscinium

25 күн бұрын

Yeah, I don't wanna be mean to the guy, but I really don't see how the curved rectangles on the tips could be anywhere near optimal even for that design. I feel like they should be at least a little rounded in some way, right?

@mitchib1440

25 күн бұрын

"9/10 chance of winning" *literally got beaten by every other submission this episode* gg, nenad.

@Sonnell

25 күн бұрын

@@mitchib1440 Perhaps he thought the chart was reversed, 9/10 chance of loosing? :)

@roderik1990

25 күн бұрын

Though I do wonder how that prop would have worked with more power and higher RPMs (assuming it survives that)

@bigmock141

25 күн бұрын

Time to short

“So cool.” Little old Asian man was just genuinely interested in what you where doing and was probably bored, just out on a walk and I bet seeing what you where doing made his day and gave him something to talk about. Awesome how being creative and interesting draws interest of strangers, I don’t know why more KZreadrs don’t do public shows or lectures and stuff.

@evanray8413

13 күн бұрын

Wrong. Was a Spai.

@Juddly05

13 күн бұрын

@@evanray8413came here to say the same thing lol. That’s probably my military training and bias’s

@evanray8413

13 күн бұрын

@Juddly05 I'm just a skeptic. No training at all. 🤪

@Thelongmanable

12 күн бұрын

*_As a long time RC boat enthusiasts you get people come to watch no matter if it's raining cats and dogs outside and the questions never end._*

@Cristopher.C

7 күн бұрын

"so cool. but you doctor yet?"

why do i keep watching these videos? I hate water, i dont care about boats, propellers ive never even thought of in my life YET im here for every damn video and i love em all!

@m1kalD

20 күн бұрын

Curious isn't it. I'm similar. He obviously has a serious knack at making things we are NOT interested in interesting.....

@Johnnywhamo

15 күн бұрын

Who TF hates water? lol

@Allexz

15 күн бұрын

@@Johnnywhamo​​⁠water is generally always too damn cold and when it comes to low temperatures im a wimpy bitch xD

I love this format. - Shit on the bad designs and mock submitter's overconfidence - Test props - Shit on the designs some more, but with data

@Eis_

24 күн бұрын

"See. Look at the graph. I told you it would be bad."

@wobblysauce

24 күн бұрын

And the huh... I guess it works, but why?

@chillentheboundarylayer6770

24 күн бұрын

BAHAHAHHA this is gold

@alveolate

23 күн бұрын

THOSE DUCKLINGS HATCHED THEY'RE FUZZBALLS ...yeah low reynolds number ain't shit if prop design is crap

@youvebeenspooked

23 күн бұрын

And mock their underconfidence haha

I love how an interesting RC channel turned into a seriously scientific resource for water propulsion.

@alveolate

23 күн бұрын

i predict that in 5 years we send a probe to europa

@firenado4295

23 күн бұрын

you missed the bit where this was not only and RC channel but an RC aeroplane channel lol.

@KyleReynaert

22 күн бұрын

Honestly it feels like he saw how successful MajorHardwares user submitted PC Fan series was and said “hmm I can do this for propellers” either way I’m here for it

@OneCanisLupus

21 күн бұрын

I am pleasantly surprised to find your channel and your testing. Always wondered what the best prop would be. Just fun to watch.

@Deletirium

19 күн бұрын

Right? I'm not even into RC stuff, at all, but I subscribed anyway. Fluid dynamics and homebrew engineering is more fun than it seems it would be.

I love how a video pops up on your feed, so you give a quick watch just to see whats going down. Then a half hour in (due to multiple intermissions, thanks wife) you find yourself subscribing and searching for the remainder of the tests. Great video, from the narration, to the cinematic views. The work and time you put into making this view is top notch.

As a retired Naval Architect I thought your experimental approach was brilliant - really enjoyed it! kind regards John

@myparceltape1169

5 күн бұрын

You will be in a good position to appreciate it.

I love this sponsor integration. You actually use it for the video and don't just cut back to the shop to tell me about incogni

When you started this I thought it would be more like the fan showdown, but honestly the amount of work you put in to make it both scientific and interesting is just amazing! The footage looks great, and the bubbles really make a big difference when trying to understand/explain the performance!

@TlalocTemporal

25 күн бұрын

Fan showdown wishes it could be this good.

@infernus6278

25 күн бұрын

At least the fan showdown guy is not shitting on people with his superior opinions and it's just for fun

@jaspervandenameele4834

25 күн бұрын

@@infernus6278 I feel like he was very objective. The results don't lie and aren't just opinions! And I feel like the prop you are probably referring to was given a fair chance, he even told him the angle of attack seemed too low beforehand! Also you gotta keep in mind how many different props (but also wings, hulls, etc) he has created himself, I love that he has some insight and gives a little hypothesis

@MrMaxeemum

24 күн бұрын

I was also thinking fan showdown (Major Hardware) or Project Farm

@infernus6278

24 күн бұрын

@@jaspervandenameele4834 im not talking about that last objectively shit design, the whole vibe of the episode is wrong

You know what I love? I used to watch you chuck foam planes out your window and now you're doing boat prop tests. Keep fing going, I love this stuff 💪🏻💪🏻💪🏻

I was so happy to hear that you ran multiple tests per model. Sometimes I see people doing tests with a single execution in situations with thousands of variables. It's ridiculous when they do that, it invalidates the entire test.

12:11 I love how you can see another prop he seems to have dropped hahahaha

@Davidus0505

25 күн бұрын

lol good spot

@gigglewumpus

25 күн бұрын

hope he picked it up haha

@romteb

25 күн бұрын

Prop 43 is sitting on the bottom

@derjoh1986

24 күн бұрын

Actually 12:07 It explains better what you were referring to.

@theseasonofcold5222

24 күн бұрын

@@derjoh1986 actually they were talking about a second fallen prop that's visible right before the cutoff.

We need more like this. Maybe do a hull design version. Set the common level using displacement and let them go wild

@vitsalava1251

21 күн бұрын

Making crowd resourced hulls is a lot of work and filament😀

@stopthephilosophicalzombie9017

19 күн бұрын

@@vitsalava1251 I thought he did a video about hull design. Not a competition, but a video about it.

I'm an old timer and physics major and congratulate you for such a professional presentation and quest! Best of luck!

You are on your way to greatness, Mr. rctestflight! Such a well planned test setup; it was a hypnotic joy to watch. Can't wait to see part 2!

Never can appreciate enough the j-cut from " oh I needed to design a custom mounting arm and foil for the slow mo camera capture" and YT pov is like 3 seconds, while who knows how long it took to implement. "Props" to you good sir!!!!!!!

@stopthephilosophicalzombie9017

19 күн бұрын

So many creators drag us through every little side project painfully. I suppose it could still be interesting but there's a limit. I appreciate his judgement.

This is like The Bachelor for nerds. I for one can't wait to find out which prop the boat ends up with!

@giorgion9116

21 күн бұрын

and the rose goes to the simpler is better

@extremechimpout

21 күн бұрын

😮 Im a nerd now..

@StormReconUnit

19 күн бұрын

Pc fan design is another one that can get this crazy imo

@Cimlite

19 күн бұрын

@@extremechimpout I mean, we're watching a competition about boat propeller efficiency - so I mean, _we are what we are._ Might as well own it. Don't get me wrong. I don't mean it in a derogatory way, quite the opposite.

@Deletirium

19 күн бұрын

Lol, very apt description.

you my friend are an engineer showing his worth, I appreciate your transparency and gratitude for the designers, keep up the good work

I like the innovative thing this video has, I have nothing with boats _just water_ but i watched the whole thing with a smile. Thanks for sharing from Mexico

Overlaping efficiency graphs with the same scale would be nice so we can visualy compare them, otherwise they all look the same

8:28 really loving the makers community embracing a more interactive YT experience with all the testing of entries.

I’m checking in every day for the next video. This was bloody brilliantly presented. Extremely interesting content great job

When I use to race hydroplanes new guys would try the hydrophobic stuff all the time, things used on sail boats and such. And they often worked well at lower speeds, but at higher speeds they actually caused more drag, sticking the boat to the water (hydroplanes run the fastest when they use air pressure under them to lift the majority of the boat off the water).

I love how you blitz through the narration. It's like you are explaining complicated, cool stuff to a friend.

I absolutely love your channel. I love how casual you are about the most amazing stuff like the "bubbler". The quality of the underwater shots is amazing. Also, I love the turtle at the end. Please never stop making videos, you are awesome

Awesome video! I love the bubble cam and all the effort you put into making this. Looking forward to the rest!

I am not, by any means, as scientific as the majority of your viewers, but I really enjoy your channel and the testing you are doing.

@amandahugankiss4110

25 күн бұрын

buddy, none of us are all thst technical. lol

@pejoka

16 күн бұрын

Not true! Some of the viewers here are technical, and some are even experts in the field of fluid mechanics. This channel is great because it’s interesting and informative for many types of viewers. It’s awesome and cool a fun stuff!

@amandahugankiss4110

16 күн бұрын

@@pejoka nope. i call bullshit. we dumb; dumb as hell.

The most impressive thing here is the camera set up that allows the props to be filmed in-situ!

Your work is absolutely incredible. I am so glad you're getting the recognition you deserve.

This was a phenomenal amount of work and effort put into this video and it shows! Excellent work. Keep the videos coming because they're all super interesting.

Wow my design is actually in the lead so far! Be interesting to see what surpasses it. Those 'stagnation points' behind the hub are partly because of the hub vortex. I actually designed a v2 of my prop with a simple hub vortex diffuser to mitigate the associated losses, but in the video it looks like the hub vortex of my design is already pretty weak so it might not make much difference. Definitely worth trying on a smaller diameter prop however.

@danedmiston9673

17 күн бұрын

That weak hub vortex caught my eye, indicating the blades are operating at a very good lift to drag ratio. Nice design job.

@nerd1000ify

17 күн бұрын

​@danedmiston9673 thanks!

@FogGoblin

17 күн бұрын

What if you added dimples like on a golf ball.

@nerd1000ify

17 күн бұрын

​@@FogGoblin Golf ball dimples are a kind of turbulator, you should go read up on how those work (it would take a bit long to write it all up here). Basically they're pretty situational, and only help when the flow is laminar and speeds are fairly low. Under other circumstances they actually increase drag. Boat propellers usually have various stuff (like the skeg and bubble generator) upstream of them that messes up the laminar flow into the blades anyway, so there's probably not much point using turbulators. Also this prop is spinning fast enough that it is mostly outside the range of speeds where they'd be useful.

@FogGoblin

17 күн бұрын

@@nerd1000ify Thank you for reply. Last comment, what if someone printed a Prop that was more like a Driveshaft and have gears that are pushed by boat moving. Or why cannot you add a prop in front and in rear? I lack intelligence but I can beat you all in imagination.

This is such a great video and idea in general - I can't wait to finish up my university studies and have more time to get making some similar projects! Great to see so many designs that I have covered in videos make it into this competition! 😀

The amount of effort you put into collecting the footage and comparing these is awesome. Can't wait for the next video

Incredible work! Really loved the camera setup and bubbler, along with the method in which you gathered your data!

OMG another rctestflight video! this quickly???

Amazing how much you've progressed since your earlier videos, I've been watching this channel for years. Great job, very enjoyable and well put together video.

@laska907

23 күн бұрын

Right! Here before Elon hires him for a high-level position at SpaceX 🙋‍♂️

You did an excellent and clever job designing protocols, building setups, capturing, analysing and communicating data and I would like to spend more time in my life involved in such cool projects.

I built RC gas boats in the early 2000s. Never got the tuned brushcutter engine to work well with the (few) available props. 20 years later, and you are providing many of the answers I was looking for 😅Keep up the awesome work, you are my favorite youtube channel.

Wageningen is a place in the Netherlands. Kinda sounds like Wah Guh Ning Uhn (accept the G in Guh is more like a soft version of the CH in loch)

@luebkejan

19 күн бұрын

MARITIME RESEARCH INSTITUTE NETHERLANDS is located in Wageningen.

@Alex-zi1nb

16 күн бұрын

Wagon ninja?

@murtoz5628

15 күн бұрын

@@Alex-zi1nb close enough!

This is some of the most visually stunning science ever captured.

Wow! Great work! Awesome! You did a great work! I'm waiting impatiently for the next video! I think the paint will better than the bubbles.

this is probably my favorite project so far. cant wait for the next videos!

That bubble generator you added is amazing. You can learn so much by being able to observe the effects like that.

Aerospace engineer, i can say that the wing vortex isn’t actually localized to the wing tip, it’s distributed across the length, just often is so concentrated that it appears as a single vortex at the tip. The long prop might simply be very elliptical in its distribution (i e efficient vortex minimization)

@vahnlewis9749

19 күн бұрын

I think I have seen several other studies where longer length is thought to be more efficient, which is helpful for solar powered systems.

@youngbloodbear9662

19 күн бұрын

@@vahnlewis9749 certainly, the longer the wing the more of it behaves like the infinite 2D wing which is almost always far more efficient. The traditional theory is that vortex related drag (proportional to lift squared, thrust in this context) scales inversely with the oswald efficiency (wing/prop design) and inversely to pi * the aspect ratio

@vahnlewis9749

17 күн бұрын

@@youngbloodbear9662 As an aerospace engineer, I would love to ask you a question about how airfoils work. I am a sailor by the way. There are two lifts on a wing, one is the Bernoulli, and the other is sometimes called Newton. Bernoulli suggest the lift on a wing relates to a vacuum produce above the wing due to the separation produced by the wing shape. The Newton force is the force of the wind pushing on the underside of the wing. I think both of these are involved in lift, but I think in many cases the Newton force is larger than the Bernoulli. Is there any reference that describes the magnitude of these two forces on wing addressing the factors of foil speed and foil angle?

@youngbloodbear9662

17 күн бұрын

@@vahnlewis9749 i don’t have a good paper to reference off the top of my head, but I can say very confidently that in most cases, most of the time, the ‘newton’ lift is significantly more important than the ‘Bernoulli’ vacuum based lift. What is really critical though is the difference between the surfaces, breaking it into components is just semantics, its the net pressure differential that generates the force. Its also important to note that if newton lift was the only thing that mattered, wings wouldn’t stall in the way they do, if the bottom surface were the only part that mattered, we wouldn’t care if flow separated from the other side, but in reality you drop like a rock. Even if the vacuum isn’t as strong as many would imply, that steady low pressure flow is still necessary for the higher pressure on the bottom to push against, because it isn’t *that* strong either. A good example is a big heavy fighter jet might have a wing loading of around 80 pounds per square foot of wing, thats only half a PSI total on average in level flight, and thats newton and bernoulli combined… even pulling maximum G’s that’s only 1/3 of an atmosphere difference in pressure. The reality though is that these simple breakdowns of newton vs bernoulli aren’t capturing the full picture. If you take a step back and look at the effect on the airflow, treat the wing as a black box, what you need to see is how much momentum is being imparted into the flow, and that force has to be reflected in the wing, basically just an abstraction of newton. When you do this, it turns out that you can back out a parameter called circulation which is equal to the lift. The more the wing causes the air to curve around it and change direction, the more force it generates, and thats due to both pushing from the bottom surface and from the suction over the top. This doesn’t factor more complex interactions with viscous flow and vortices etc but thats the gist. One last caveat is for highly supersonic objects, newtonian flow is almost perfectly accurate, the more supersonic the less these ideas of suction have time to really take any effect

@akuladon1488

16 күн бұрын

@@vahnlewis9749 Lift is created by the difference of the pressures under and above the wing. It involves both vacuum above the wing and excessive pressure below the wing. But vacuum can have around 3 times more deviation from atmospheric pressure than excessive pressure below the wing, so the most of the lift is created by that vacuum. Maybe i didn't wrote it clear, English is not my native. So here is formula of what i meant: P_above - P_atmospheric ≈ - 3 * (P_below - P_atmospheric) It is important to understand that without pressure below the wing, there wouldn't be any lift so both create it and both are used in Bernoulli lift. And Newton lift is just excessive pressure below the wing which is included in Bernoulli lift

Thank you very much for your work. You speak so clearly and relaxed. Your way of doing things and your love for the small technical details and nature. Super good!

to make it proper and show how the water reacts or goes in every prop used just by putting bubbles thru the path is totaly genius bro, i love the way you think and surely i love this video

Now you need to graph author confidence level against efficiency results!

@isaacgraphics1416

21 күн бұрын

I predict an inverse correlation

Googling the paunovic props, it really seems like they're intended for drones where they're able to spin much much faster than boat propellers usually do. So it seems like an odd choice to submit it for this contest, especially without changing it in any way for the lower rpms

@stephenhagen8976

20 күн бұрын

Yeah. It's clear he didn't check rpms or only tested it for static thrust. Interesting idea, just not optimized for situation.

@pejoka

16 күн бұрын

Kinda hard to imagine why such a supposedly “brilliant “ designer would miss the obvious scaling issue so badly.

I love this video idea. Your testing is always solid too. Keep it up!

Daniel, one heck of a kickoff for the series! The setup you built to film this is admittedly just as hard as designing a custom propeller, if not harder. Also, bless you, ya legend.

That is fantastic nerd content. There are not many creators that put so much efford in their videos. That must have taken weeks to setup. Really appreciate it.

Awesome test session! Very scientific! Love it! This reminds me of the cub scouts "rocket derby" I attended back in the early 60's. The idea of that was for the "kid" to build his OWN rubber band powered "rocket" and run it along the taught fishing line at the meet (the big test day). I carved and painted my own rocket from the base line starter kit, and got a lesson on a few different things along the way. I didn't win the event but managed to come in above the middle of the pack. The winner's "rocket" was built by some kids dad that was obviously well skilled at model building (it was like something from NASA). "Dad" added graphite powder to the prop bearing surfaces and saturated the rubber band in like castor oil or some special liquid to reduce the unwinding friction. Like a 8 or 9 year old kid knows this stuff? Lol!

I wish you could know how much I enjoyed watching this video :) 👏🏽 thanks for all your hard work. I’m eagerly awaiting the rest of the series :)

Wow, the underwater shots are just amazing. So much work for those, but man they are perfect!!!

Just realized how big of a nerd i am dammit

@maxmustermann5932

22 күн бұрын

we nerds are more fun anyways ;)

@denisivanov1140

21 күн бұрын

Why?

@shark_eye

20 күн бұрын

​@@denisivanov1140more knowladge. I like to be a nerd when it comes to stuff like this. Also made a underwater drone. Multiple times 😁

Wowee, what a well thought out test and enjoyable video. Can't wait for the next one.

I loved this :) Great video and can't wait for the follow ups.

I have been watching a PC fan series and this came across my stream. You did a great job and have a new sub. Good luck in the future.

Thank you so much for testing the hydrophobic coating; it’s something I’d wondered about for a long time Same with tubercles too omg

Amazing that you come up with details like the idea of air bubble injector. Also, this is video is very useful because I'm building a simple catamaran that can carry a large magnet for magnet fishing, so I don't need to mess with propeller testing.

@tylerlaird91

25 күн бұрын

watch techingredients video about electric catamaran propeller. he did the testing and arrived at a 3 blade ccw pusher prop being the way to go I believe. i kept hoping one of the designs was going to be similar to that but none were:\

@jumpsneak

24 күн бұрын

​@@tylerlaird91yet...

@tylerlaird91

24 күн бұрын

@@jumpsneak 😄

I watched a few of your vids over last year and though I don't do anything with models etc _ I enjoy the way you meticulously work through your project and explain everything with good detail and simplicity.. Well worth a sub and like.. Keep up the great content

Wow love the content and way you and your team systematically prepare and test Items…keep up the great work!

Great work man, good methodology, no BS and honesty and willingness to be wrong and accept that. Something we can all learn from. New subscriber 👍🏼

Epic video and sneeze, can't wait for the next one! So far it seems like more plastic == less efficient. By this metric, you should try the motor without a prop, it should be super amazing! :P

13:04 bless you bro😂

That was very informative, entertaining and enjoyable. Must watch all 3 parts now, im invested 😂 Subbed!

Absoluetly wonderful! I had so much fun :D Congrats to these extremely cool Angles underwater. These shots with a wider angle looking slightly to the bow. mhm.

Your videos are so great. I’m studying maritime technology in Germany and you motivate me so much for more!

13:04 bless you

@thomasdaneault2176

20 күн бұрын

Crazy I was going to comment that’s if you hadn’t 😂

@endurofan9854

12 күн бұрын

why? what's at 13:04?

Don't know how this video made it to my algorithm, but I'm happy it did. Kudos to the effort spent with the underwater setup.

This is incredibly interesting, and the video quality is amazing.

Propellers aside it is neat watching your test platform evolve. That little catamaran is cool.

love your vids because of you got in to engeneering

awesome work! i love how the simple is the most effective.

Used to work pit crew for outboard hydro racing. The props were stainless, with 2 blades, running the hub partially submerged. Boat speeds varied depending on engine displacement, but 120mph with a 40 cubic inch engine were common. We noticed the higher the rooster tail, the slower the boat. The 60 cubic inch engines were throwing out grapefruit size water "chunks" at no more than 6 to 8 feet high. The winning prop would have worked great, but 300 horsepower required thicker blades.

Damn dude you really are alive at your perfect time. Can you imagine trying to have this channel without a 3D printer?

Right on bro, you do an excellent job with everything! Subscribed.

This was one of the coolest videos I’ve ever seen!!!

Wouldn't the fibonacci propeller be GREAT for avoiding seaweed snags? I think that sucker could run through a bass lake no problem where other propellers would get caught up in growth

@michael3533

25 күн бұрын

Rounding the edge at the start of the vortex could help a lot by driving through seaweed too

RIP "Paunovic" Hope the patent costs are worth it for you lmaooo Let this be a lesson - don't get cocky.

@frankdobs

25 күн бұрын

Most patents are done in hopes of it being used somewhere else and owning rights

@ABaumstumpf

25 күн бұрын

@@frankdobs But at least they should have even the slightest chance of being useful.

@thegforce522

25 күн бұрын

considering it was mentioned to be "quieter and more efficient than a regular drone propeller" im assuming this design was made with air in mind and not water. water really just is a different ballgame.

@mitchib1440

25 күн бұрын

@@thegforce522 but it was submitted for a water challenge...

@thegforce522

24 күн бұрын

@@mitchib1440 yup, seems the submitter underestimated how vastly different water props are. it would also make more sense as to why the pitch was lower, and why the efficiency curve was going up. it is probably made for much higher rpm and lower torque applications.

I'm loving the Major Hardware vibes! These user submission videos are always fun. :)

this video series makes me so happy. the bubbler is genius, very well done!

19:20 coolest visual I've seen in a minute, like a ancient Japanese painting of the ocean.😎

@costynvd

24 күн бұрын

It's so cool!

@r3dn0w

24 күн бұрын

Looks like a Kelvin-Helmholtz instability. 😏 (I think I learned that from Veritasium ..)

21:00 Likely this prop never reached its efficiency peak, while all other props always started past it. The full efficiency graph should be like a mountain, not a single slope

@8paolo96

25 күн бұрын

It clearly couldn't reach higher speeds, anyway you can see it almost at plateau in the end of the curve, and with the "corrected parameter" calculated at the apex it was still dead last

@karyjas1

25 күн бұрын

@@8paolo96 Well, it was so clear to me that i didnt think to even mention it

@DumbGoogle-yz9cr

25 күн бұрын

Remember they designed this prop for the 400 watt motor with a target speed aswell, if it didn't reach full efficiency then it was badly setup for this motor. All props regardless of style or design need to be correctly sized (diameter and pitch) for the motor driving them this is standard in the boating world. Also given how badly the prop performed and the angle on the graph it should likely would never reach a efficiency remotely close to the other props, also note the design was intended for metal it should have been altered for plastic (knowing it was going to be printed) as it may not have broken but it may have been flexing altering the intended pitch angle and hurting the efficiency more. The final nail in the coffin for this design really is the flow, the goal of a prop is to push water backwards any water moving in any other direction is a huge efficiency loss and those swirling vortexs moving at the outer edges of the blade looked to be around 20% of the blade lenght a huge section of the blade that was effectively fighting its ability to push water backwards

@conorstewart2214

24 күн бұрын

The propeller on that motor couldn’t reach higher speeds, so how does the efficiency past that point matter if it is unable to run at those speeds? It did reach its efficiency peak for that motor.

@iskierka8399

22 күн бұрын

@@DumbGoogle-yz9cr Resin is actually extremely inflexible, it will shatter with not much more bend than metal would. The fact it didn't break already tells it wasn't flexing, it was just so inefficient that it couldn't perform well enough to break itself.

Really love the time you take to create an amazing underwater image of what’s happening with the propellers

22:30 I love that random encounter with a guy just asking what you're doing and then getting really interested as soon as he understands what's going on.

You should try to sync a strobe light to one of the motor phases. Maybe an car ignition strobe light will do, they usually have battery connections by design.

I hope this becomes a regular thing like the PC Fan showdown 😂

@Drachenhebron

23 күн бұрын

thinking the same thing, now i have to go check that out see if anything's new.

Very nice to be able to see the testes like that. Thank you!

Great tests, love the vortex shots

If only I had noticed that previous video for this competition, I might of submitted something, Although I really look forward to seeing how all these propellers compare!

Perhaps many entrants confuse aerodynamics with how fluid dynamics works in water? As water is not really compressible, while air is. In Aerodynamics compression, low and high pressure differences play a huge part. In water this is negligible compared to that.

@SandFl0h

24 күн бұрын

If the airsped is below ~100 m/s you consider it incompressible as the effect is neglectable. The only real difference, apart from viscosity, is cavitation.

@SandFl0h

24 күн бұрын

For that guy with the patent, the problem is somewhere else. Even for air, his propeller would be shit. You can compare it a bit to airplanes. He built a bipline-equivalent. Biplanes only advantage is structural integrity. It is easier to build them more rigid. That's why they were mostly used early on when materials etc. were not so advanced. The most efficient airplanes are gliders (yes, the concept of aspect ratio does apply to propellers).

@falcofranz5005

23 күн бұрын

If pressure differences would be negligible then cavitation would not be an issue, so your statement is invalid.

@Sonnell

23 күн бұрын

@@falcofranz5005 Well, happy to disagree. First, read my comment. I wrote, "negligible compared to that". I did not write "non existent". And what I wrote is true. Water is not compressible, while air is hugely compressible. Completely different in this regard. Cavitation is a very special effect. It only happens at a very low pressure, and suddenly. It does not happen at high pressure. And it happens at a special case. In all the other pressures, and pressure differences it does not appear, and does not have any effect on the effectiveness of the propeller. Like 99% of the time. While air pressure differences affects the effectiveness of the propeller 100% of the time. So it is truly negligible compared, and it can be handled very differently than other aerodynamic effects.

@falcofranz5005

23 күн бұрын

I think we both agree that the flow dynamics in air and water are very different, since water is incompressible and can undergo a phase change. Also the viscosity is different so the production and dissipation of turbulence is also different. Also the speed of sound is higher in water so shocks are unlikely to appear (cavitation will occure before that). What we disagree on is the term „negligible“, which I think is wrong here, because cavitation is a phenomenon that indicates drastic pressure drops. And since cavitation is very lossy it is in my eyes a defining factor and not a negligible effect.

So much effort man! But it pays off with such a cool video for the whole world to see and learn! Thank you from Warsaw, Poland!!

Impressive prep for the series! 10/10 video.

I noticed the "patent pending" blade completely changed shape under load. I think it would perform completely differently if it weren't so flimsy. Not necessarily *better,* but different.

Lake house for cheap... good one.

Very impressive! Thanks for putting in all this work and sharing it.

i am so impressed of your great test! so much time spending on testing propellers! very nice! thnak you!

Fuck, that sneeze was epic 😂😂😂 well done mate. Well done. Oh and get well soon lol 😂