Hearted Youtube comments on Ziroth (@ZirothTech) channel.

  1. 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.
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  2. Major props to the inventors.
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  3. As a former submarine sonar tech you have no idea how terrified of cavitation I am 😂
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  4. I had always understood that this was not a "problem". It was known perfectly well that fusion power would not be usable, unless we had fusion reactors that could use only deuterium as fuel. Current attempts at making fusion reactors with deuterium and tritium as fuel are only intended as a steppingstone on the way to building a fusion reactor that will actually be useful.
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  5. I feel the fish will be crushed between the ball and sidewall like a mortar and pestle.
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  6. 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.
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  7. Marine Biologist Frank Fish? You cannot make this up!
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  8. In Australia we have this energy freely available in a town called Portland which is in Victoria but the authorities closed it down, it supplied thermal energy to the hospital and heated the local swimming pool. Greed at the top end stopped us using it. Power companies must do favours for the rats that are in power.
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  9. " ...a team of researchers from Wuhan University..." This is gonna be a hard sell.
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  10. As a drone pilot, I love the idea of quieter flight & improved rfficiency! Hope these make it to the marketplace soon! 🙂
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  11. Two (semantic-ish) points: It's not exponential if it goes by the square. And saying "temperature is 23 percent lower/higher" is basically absurd as it's scale-variant.
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  12. Pro tip: don't put "insane" in your header. In 2024, it means "mediocre clickbait".
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  13. "Nuclear Fusion's Biggest Problem" is that' it's not working, so they made it work? No? Title is misleading.
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  14. Tritium breediing does not have to rely on the fusion reactors, it can also be done using other neutron sources. It adds to the cost but is feasible. As for the Lithium 6, as soon as te demand is there the facilities will be uilt, just like with any other material. the process of enriching it is well understood and the fact that a site that was poorly run decades ago is no longer operating does not necessarily mean that the method itself is unsuitable. Other than that a good video.
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  15. Technically, no one can say that this technology isn’t revolutionary.
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  16. Unpopular opinion: Hydrogen powered vehicles are the new fusion reactors of our time. They will always be 20 years away from full adoption.
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  17. It was an absolute pleasure speaking with you! Thank you for telling the story of industrial decarbonization via electric thermal energy storage.
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  18. It's crazy how much improvement can be made to everything we already have.
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  19. The German Engineer joke: "that's all fine and good in practice... but how does it work in theory?!?" 😂😂😂
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  20. 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.
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  21. This would be great for off shore sailboats and motor boats which use "water makers" to produce fresh water. These units are reverse osmosis devices but they use a lot of power which is a problem for boats running on solar.
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  22. 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
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  23. I have pulled my 3 man canoe along with a kite before. Good fun and very fast.
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  24. "Dams can cause negative impacts if they break". Bit of an understatement 😆
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  25. as someone who has spent most of the last 18 years on oil rigs, as a geologist, and later an engineer, I can say that the process to drill deep geothermal wells is not really any different to conventional oil and gas drilling. We have the technology to drill very deeply already, we don't need this new plasma method that will use an incredible amount of electricity. Just because some technology exists, doesnt mean it's going to be affordable, or applicable. Geodynamics, a company in Australia already built a proof of concept for enhanced geothermal, or hot dry rock geothermal (look for Geodynamics Habanero project). They drilled multiple wells to only 4-5km deep, and circulated water between wells, generating steam, and electricity. One major economic hurdle was affordable corrosion control, not the technology to drill the wells. Conceptually, it's awesome, no need to burn fossil fuels, etc, but the reality is that there is no point building an amazing system if you cannot maintain the equipment and sell the end product at an affordable price.
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  26. 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!
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  27. This is the first I have heard of Rondo Energy, so thank you for the introduction. However, I would like to hear more technical details about their heat storage battery. Pros: 1) off the shelf technologies 2) simple, long life materials 3) high output temperatures (compared to other heat storage technologies). I love this part of the solution. Cons: 1) I am very skeptical of the stated 98% storage efficiency mentioned at the start of the video. Usually, when talking about storage technology, people quote the "round trip efficiency", meaning, what percent of the input energy comes out durring discharge as usable energy. However, I suspect you are quoting the charging efficiency, meaning how much of the input energy is stored in the battery, ignoring how much energy is lost durring the extraction process. If you really do mean "round trip efficiency", then this statistic is so outlandish, it really is "too good to be true", and begs for justification and a heavy dose of skepticism. This would be astounding, and much higher than any of the other heat storage technologies. Lithium ion itself is typically stated to have 90% round trip storage effeciency, which is higher than any other heat energy storage technology that I am aware of. 2) There is no explanation of how the heat (ie, hot air?) used after it leaves the battery. I can imagine a few uses, but some solid real world examples would have been nice. 3) There is no talk about the ideal storage charge/discharge cycle time. Is this technology better suited to be used for short term (4 hour) medium term (8 to 12 hour) or long term (days/weeks) storage?
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  28. Flaps on landing. Whilst they do increase drag when deployed and therefore reduce airspeed as you say, their primary function is to maintain lift at lower airspeeds. 😊
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  29. Hello, the clip at 0:30 is from our 3D printed EDF video. We would appreciate if you included the original as a source in your video description. Many thanks.
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  30. Again "slapping a turbo on it" was the solution.
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  31. I am an ex laminator who worked with carbon fibre for motor sport, aviation and oil industries. The process of the bonding of the hull to the Titanium caps looks extremely questionable. In the videos I have seen the were hand mixing adhesive in buckets, applying with plastic scrapers in an environment that was not dust or dirt free. Frankly I am shocked it went as deep as it did. Maybe methods have changed but it is not an assembly environment I am familiar with.
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  32. It was mentioned that the Titan dropped it's weights few seconds before the implosion. So odds are that they started to hear some type of crackling sounds either from the hull or from the glass viewing window. So the operator must likely dropped the weight to immediately surface but it was too late. The unit was already too far damaged and it gave way and imploded.
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  33. 3 percent isnt as bad when you think about how many tons of freight a ship can move.
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  34. Quite fascinating. Remember the invention of the blue L.E.D. changed the world as we know it.
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  35. Such a cool innovation with a surprising amount of applications! Hopefully they become more cost effective in the future!
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  36. 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.
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  37. Love to see the effects on massive ships like cargo and cruises
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  38. 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.
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  39. I live in Kiribati and I was on Banaba during the drought And we are are tying to facilitate a small drill rig for simple wells; Love your article, accurate, too. The question is : when will it be available ?
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  40. The most important metric of a wind turbine is the levelized cost of energy (LCOE). This metric allows you to compare all forms of energy generation in terms of total energy return during the lifetime of operation per investment dollar spent.
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  41. 4:22 this has actually been true for all sail powered boats for as long as we have sailed. Sailors want a side wind more than a tail wind. If the wind is blowing behind you to the front of the ship, then the faster you go, the slower the wind is relative to your sail (if you're going 20 mph and the wind is 30 mph behind you, it loses speed catching up to you and hits the sail at 10 mph). your ship will not get any faster as soon as the wind hitting the sail is too slow to overcome the friction. If the wind is hitting the side of your ship and you use the sails to deflect it backwards, you could be moving at 50 mph and you will still have wind hit the sail at 30 mph.
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  42. regardless of what you think about Elon Musk, you have to respect the man for generating so much hype about electric vehicles and a renewable future.
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  43. Thank you for mentioning the downsides of cycloidal rotor propellers as well
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  44. 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.
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  45. If you want to be blown away about some of the limits of flywheel / gyro tech check out the specs on NASA mission Gravity Probe B. Its gyros were so sensitive they could measure the phenomenon of “frame dragging” which is the literal dragging the fabric of space by a moving mass. Everything about that mission is interesting worth looking up if you’re into that kind of engineering.
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  46. Having different colored and designed kites could make it a nice tourist attraction too. If our energy production can also be an art installation we can inspire people with a more creative side to get into energy production.
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  47. Great Video Ryan! I love the point you make that solid-state isn't the goal, its higher density batteries and lithium anodes... It's fascinating in science and engineering when we develop one type of technology for decades, only to see it surpassed by some new contender no one sees coming.
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  48. amazing how many designs that we previously thought were so efficient, have still so much to be bettered.
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  49. Flywheels made of depleted uranium have also been used in energy storage and are used in the primary coolant pumps of nuclear power plants to ensure a long coastdown in the event of a power failure.
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  50. 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.
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