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• echodot@feddit.uk ⁨2⁩ ⁨months⁩ ago

  Basically they’re trying to claim that the Bernoulli principle is some amazing concept that only they’ve come up with.

  Their fans do work in the sense they do move more air but it creates so much back pressure that most of that air movement is lost. So you might as well not bother.

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• GTG3000@programming.dev ⁨2⁩ ⁨months⁩ ago

  You’re basically trading energy to move higher volume of air. The fan can move smaller amount of air at higher speed, but larger amount at a gentle breeze feels nicer and helps with circulating the air in the room better.

  You could achieve it by taking that exact motor and slapping a bigger fan onto it, but that looks less cool and probably produces more noise? Maybe there’s some efficiency differences if the motor is better at spinning fast, but as a spherical cow in vacuum it should be similar.

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  • Alcoholicorn@mander.xyz ⁨2⁩ ⁨months⁩ ago

    It’s cheaper to make electric motor spin fast with low torque than slow with high torque, a ceiling fan of the same cfm needs a bigger motor than a standing fan.

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  • Threeme2189@sh.itjust.works ⁨2⁩ ⁨months⁩ ago

    I would counter that a small fan spinning at high rpm makes more (annoying) noise than a large fan spinning at a lower rpm.

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    • 666dollarfootlong@lemmy.world ⁨2⁩ ⁨months⁩ ago

      But due to it being hidden maybe it can be isolated easier?

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      • GTG3000@programming.dev ⁨2⁩ ⁨months⁩ ago

        Yeah, the fan being completely shrouded in plastic will dampen a lot of noise. And for the price, the fan is probably well balanced and somewhat optimised. From what I recall, the dyson bladeless fans are near silent.

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  • rethnor@lemmy.zip ⁨2⁩ ⁨months⁩ ago

    So it’s like a lever, you aren’t just magically getting more volume at the same speed without more power, it just slows down when interacting with the outside air, ie conservation of momentum

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• reksas@sopuli.xyz ⁨2⁩ ⁨months⁩ ago

  maybe it works kind of like how water works. Water also sticks to itself, like how separate droplets combine very fast when close enough.

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  • echodot@feddit.uk ⁨2⁩ ⁨months⁩ ago

    Well in fluid dynamics you don’t really make the distinction between liquid and gas. You can model air as basically just a very low viscosity fluid and it works. No one really knows why it works because it shouldn’t, air doesn’t stick to itself, but if you pretend that it does the simulations still work, even though they’re wrong.

    If you look in most physics textbooks even at quite a high level they will tell you that aircraft fly because air sticks to itself, but again, it doesn’t. No one is quite sure why aircraft work, no one’s all that certain where the lift comes from. But physics textbooks hate to admit that so they just pretend that air sticks to itself.

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    • rethnor@lemmy.zip ⁨2⁩ ⁨months⁩ ago

      The whole air moves faster over the top than the bottom, why would it do that? It’s not like the on the top of the wing and the bottom of the wing are connected by magic.

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