I Found the Most Efficient Propeller Design - Competition Ep. 3

Props to this guy....

The honorable mention for this video is the bird who bombed you in stealth mode.

i like the side story about the drone owner

That the toroidal is so much quieter while matching the performance of the baseline is actually a big positive if you think about it. Reducing noise and thus potentially vibrations could be quite the big implication for some applications.

It was so much fun having a chance to design my prop for this competition and flex some of the aero engineering muscles from uni. Can't wait for round 2 :). Most of the bugs in my design workflow and software were ironed out during this round, so there is nothing stopping me from placing top 3 next time! Congratulations to Spanmaxxing, Bigger (Diameter) is better, and Prandtl-DAE!!!

33:50 Military ships often have variable pitch propellers. Arleigh Burke class for example, and the props are huuuuge. And they have a bubbler system too to mask prop noise.

Can't believe I'm actually excited to see a THIRD episode on propellers!

"Next I've got these human growth propellers from a science lab, these were actually designed on the backs of real human beings."

A showdown for the ages 🙌

Thanks for testing my poorly proposed prop! Nice touch with the Sea shanty lyrics

Variable pitch propellers are actually kinda common on fish trawlers, which need to operate at two speeds efficiently: The travel speed and the harvesting speed. This also helps with maneuvering, as they can seamlessly switch between forward and backward operating in fractions of a second and thus can keep the boat stationary at a certain location (if they got a bow thruster). So deep sea diving boats have also often also have variable pitch propellers, which can sometimes freely rotate. But the pinnacle of maneuverability - sometimes used on tug boats - is clearly the Voith Schneider Propeller. But it's also pretty inefficient - for obvious reasons. BUT they have a low acoustic signature - as they don't have any cavitation, as they don't have tips (there's a thrust plate at the bottom). :)

This tickles a tism I didn't know i had.

Great episode! Thanks Daniel for using our template, helping expose the HAVF airfoil format, and being so patient with our first foray into marine propellers! I love the content!

38 min video to kick off the friday, Daniel you know the way to a man's heart

I know far more about propellers than I ever wanted to know, and my life is immeasurably better for it

This confirms he is using us to make the most efficient solar tug boat yet

As a maritime engineer with experience on model tests of propellers, this is very interesting. The different aspects of propeller design are nicely shown and discussed here. As for the cavitation, the large propellers are more prone to it due to the high tip speeds. When doing model tests with roughly similar sized propellers than tested here, the pressure of the test section is lowered to 20-40% of the atmospheric pressure to match the cavitation of a full-scale propeller.

I think there's a few problems with tubercles. In nature they're strongest on the side fins rather than the tail fin, which often won't even have any. Essentially they're more useful on the whale's "rudder" than the whales "propeller". Which might key us in to their actual purpose. Further, whales are not speedsters. While a blue whale CAN hit 30mph they're usual pace is 4-12 mph. While the boat in these tests is within that range, the propellers are moving fast enough to "reverse" in the camera meaning they're rotating at a pretty serious clip. So the tubercles that are usually on the steering part of a slow animal are being placed on a high speed propulsion part. Somewhere nature simply never intended them to be. Even more, they're not made for this kind of motion in nature. Even when the whale is zooming the tubercles on the tail are going up and down (changing direction) with slow downs and even stops. But on a propeller it's just a constant rotation in one direction. If tubercles do offer an advantage to boats it'll probably be on the body or the rudder.

Wow! Brilliant research series! You are just casually uploading videos with far more research content than many bachelor thesis out there.

Contender-25 is realy intresting one, same diameter with baseline, but as big top speed as spanmaxxing is great result i think if there will be another competition, you should limit maximum diameter at baseline propellers diameter, so it will be competition of form, not size