• NarrativeBear@lemmy.world
    5 days

    Its true there is a fan in the base of all bladeless fans, but the fan is smaller then traditional fan designs and moves the same if not more air then traditional fans.

    Air is pulled in through the base and forced through a thin slit. This fast stream of air creates an area of low pressure, drawing in and amplifying surrounding air behind the slits.

    Because air “sticks” to itself, when you get some air moving (by breathing out, for example), the initial bit of air that you move “drags” some air with it from beside and behind. This is what Dyson calls “air multiplier technology”.

    Dyson uses this property of air to claim that they only have to move a fraction of air (with the fan in the base) of all the air that blows past you.

    Here is a example of how this works, and how you can use one breath to fill a large bag.

    https://www.youtube.com/watch?v=rAAelB7nN14

    Here is a image of the multiplier effect, from the original intake of air at the bottom. You can see the air is multiplied from behind and infront of the fan.

    1000063718

    • ToxicWaste@lemmy.cafeEnglish
      4 days

      still a miss-labeling to call them bladeless fans, just because the blades are hidden. by that logic my beef raviolis are vegetarian (tbf: the catholic church made a similar claim during the medieval ages).

      Bernoulli Fan is not only more accurate, it also sounds much cooler.

      • rumba@lemmy.zipEnglish
        4 days

        Tesla sounded like a cool name for a car too…

          • rumba@lemmy.zipEnglish
            4 days

            And weren’t dangerous/death traps for no good reason. And had good service practices, and weren’t anti-resale.

            Mr. Tesla is certainly rolling over in his grave.

    • rethnor@lemmy.zip
      4 days

      I’ve never really understood this multiplayer thing, sounds like a free energy gimmick. You can move more mass at the same speed without putting in more power.

      • GTG3000@programming.dev
        4 days

        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.

        • rethnor@lemmy.zip
          4 days

          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

    • hOrni@lemmy.world
      4 days

      A traditional fan also pulls air from around its blades using the same principal. A bladeless is just a gimmick it has no actual benefits.

      Here’s a video on the subject:

      https://www.youtube.com/watch?v=ySSo5PmZZJM

      It turns out, a bladeless fan is even less efficient than a traditional one. It works better, when you remove the casing.

      • Seppo@sopuli.xyz
        4 days

        Of course they have benefits. Depending on the situation of course. I wouldn’t put one in my computer, but I sure as shit have one in my home with a kid running around. Turns out a fan with all the heavy spinning hardware stuff in it’s base is less likely to fall over than one with all that stuff up on top. Honestly all my Dyson stuff work fucking great for their intended purpose.

        Paying the absolute minimal amount for something isn’t necessary the goal of life. You’re not a corporation.

        • hOrni@lemmy.world
          4 days

          None of what You said is about efficiency, which is the subject here. Not paying corporations for bullshit is one of my goals in life.