The Unexpected Genius of Bionic Propellers

Marine Biologist Frank Fish? You cannot make this up!

As a former submarine sonar tech you have no idea how terrified of cavitation I am 😂

As a Merchant Mariner, this is really exciting. Always a good day when you learn of a new technology that increases efficiency while ALSO helping the environment. It's a win-win for everyone.

Probably one of THE MOST important data points I've never even heard about! Absolutely remarkable! I've worked in the U.S.Air Force as a Jet Engine Mechanic and can say I NEVER envisioned this but was completely blown away at the context of this idea - coming from Whale fins??!! How mind blowing!

Recently, I had an enlightening experience while using a small electric motor on my boat. I want to share this because it illustrates the significant impact that underwater noises, like those from propellers, can have on marine life.

While I was out on the water, something remarkable happened. I switched the motor into reverse, and to my surprise, a seal popped its head up out of the water. Intrigued, I stopped the motor, and the seal submerged. But when I hit reverse again, the seal resurfaced. This wasn't a one-time occurrence. Each time I alternated between forward and reverse, even from a distance, the seal would respond by appearing while the engine was in reverse.

This was particularly striking because the motor I was using was very small and relatively quiet – an electric model. Yet, the seal's reaction was immediate and consistent. This interaction, as amazing as it was to witness, really drove home a crucial point for me.

It made me realize the profound effect that underwater noise – from things like propellers and even sonar – can have on aquatic creatures. The fact that even a small, 'silent' motor could elicit such a clear response from the seal underscores the sensitivity of marine life to our human-made sounds in their environment. It's an important consideration for all of us who spend time on the water and a reminder of the broader environmental impact of our activities.

Just wanted to make a correction. At 1:57 there's a picture of a propeller that supposedly has cavitation damage. This is actually a picture of a brass propeller that's in the process of being repaired. The outer edges have been welded and the "cavitation damage" is actually the weld that was added to repair the propeller. This will be ground down to match the original shape of the propeller. Thought I'd clear that up incase anyone was confused.

I must say, having used some 3D CAD/CAM drawing programs to design propellers, these are insanely cerebral from the onset. But introduction of tubercles to the edges makes these ever more insanely complex. Your presentation was professionally presented so that anyone could understand this content without struggling. Good job, Ziroth!

I've long been interested in nature being the template for human design. As a kid I made clay models of cars and ran water over them to see how the natural flow affected the shape. So I'm fascinated to see this.

There is a computer fan maker called Noctua from Austria. They have been well known for making quiet fans. If you go their website you will see the same flutes on their fans. This idea came to them more than 20 years ago, after their R&D labs led them to fine tune their observations.

I did my dissertation on tubercles, the effect did not seem to be a primary effect of vortex or mixing as would seem intuitive but having a wing with a blend of chord lengths. This in effect smooths the lift/drag distribution so that the wing does not perform as per one specific aerofoil geometry but a blended solution of the chord ranges. This is not so useful for lift generation which can be designed for specified efficient parts of flight but it is useful for maximising the Angles of attack a control surface can be used at - it is not surprising in the end as the humpback whales use the fins for rapid turning and mobility for prey catching, not propulsion.

I first learned about cavitation and its destructiveness as a mechanic working on Caterpillar hydraulic systems; how it would destroy the vane type hydraulic pumps needed to drive the massive rams on Cat scrapers and loaders. Later I learned about the noise issue as it relates to, particularly, submarines and how the U.S. Navy went to extraordinary lengths to keep the design of its submarine props, enshrouded, LITERALLY, in secret and how they could tell exactly where a Soviet submarine was simply by its noise signature. Even now, when you see pictures of U.S. Navy subs in drydock, their propellers are wrapped to keep them hidden from prying eyes. Truly fascinating stuff.

Absolutely brilliant! And, as a spin off, understanding the dynamics of humpback whales was really awesome. I'd never thought how amazing it is that such huge animals propel themselves with such seemingly 'clunky' fins! Phenomenal!

amazing how many designs that we previously thought were so efficient, have still so much to be bettered.

The inner kid in me is so happy to see so much research & testing being done around Biology inspired designs. Then Add in our advancements in material science, engineering, software performance testing methods, etc. I really think we are going to be surprised by what we end up developing. Each development could be unique and useful in different ways. For different tasks and so on. It's just awesome to see so much curiosity and development being combined in this field of productivity.

I've owned boats for years and messed around with different props, they're incredible things the slightest adjustment to the blades size wise makes an enormous difference in slippage and performance, very interesting video a new subscriber gained.

Well documented, well researched, not forgetting to highlight some drawbacks or hinderances as well and beatifully produced. That, sir, is worthy of my subscription :)

you're teaching me about so many types of propellors, literally couldn't think of the type of designs... amazing what innovation can do, thanks! :)

The ribbed propeller reminds me of vortex generators on an aircraft wing. The trick to fluid dynamics is balancing the tradeoff between lift/drag/weight and thrust. I love this presentation!❤

Fascinating! Excellent presentation, YouTube needs quality content like this very badly now. Subscribed.

I love it when I find a new channel that is as well produced and researched as this one. New subscriber here, this was fascinating!