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Producing a vacuum using a turbine?

  1. Aug 8, 2011 #1
    Hi:

    I’ve been trying to figure out how does the spinning action of the turbine blades in the video produce a vacuum so as to draw air down the shaft? I don’t see any venturi effect taking place. A bit puzzling on how this gadget works?:confused:




    http://www.toring.com/What_is_ToringTurbine.html
     
    Last edited by a moderator: Sep 25, 2014
  2. jcsd
  3. Aug 8, 2011 #2
    I think it works just like any centrifugal pump is supposed to work - it is pumping air into the water.
     
  4. Aug 8, 2011 #3
    I had thought about that but the blades on the centrifugal pumps I've seen are always kind of curved all the way toward the center of the pump in order to scoop the water as it enters the center input. The blades on this gadget are "straight" and don't appear to extend very far inward toward the center. It's difficult to conceive how and where does it scoop water or the air to produce the suction effect.
     
  5. Aug 8, 2011 #4

    russ_watters

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    That was my thought as well, but it is tough to see past the marketing bs in that link.
     
  6. Aug 8, 2011 #5
    I would like to buy the thing but Europe is too far away to order, so I was going to try to build one similar. I want to aerate a fish pond with it. Thanks for all your inputs.
     
  7. Aug 8, 2011 #6

    russ_watters

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    No, blades on a centrifugal fan/pump don't need to be curved. The exact shape will depend on the particular requirements.
     
  8. Aug 8, 2011 #7

    RonL

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    The same principles as used by Tesla's Turbine and Pump, and why few people really grasp the operation as claimed by Tesla in his patents.

    Ron
     
  9. Aug 8, 2011 #8
    I don't know about the Tesla pump. Does it have flat impellar blades like this one? The only thing I can come up with is that there is water that freely comes up into the unit through a hole in the bottom center, and the flat spinning blades fling this water outward faster than the rate of water coming in, thus causing a vacuum which sucks the air in through the top shaft to mix with the water that's entering from the bottom.
     
  10. Aug 8, 2011 #9

    RonL

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    Viscosity and adhesion of water against the spinning blade surface, causes a pressure force outward and a low pressure area at the shaft, atmospheric pressure pushes air into the low pressure area, where spin velocity distributes the air into the water. The diffusion of air looks very impressive and is a curiosity for me.

    Corrections if needed, please.:shy:

    Ron
     
  11. Aug 8, 2011 #10
    It is a centrifugal pump and works the same as all centrifugal pumps. How long the blades are (along the radius) will effect the head (pressure or suction) developed. The curvature of the blades (or lack) will have some effect on the performance versus speed and the noise output. When the pump is started the blades start spinning the water and accelerating it in the direction of the rotation, as it gains speed centrifugal force moves the water out of the turbine, that creates a partial vacuum that draws air down the shaft. As with any pump there will be a maximum head it can create and therefore a maximum depth that it can pull air down.
     
  12. Aug 8, 2011 #11

    russ_watters

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    It doesn't look to me like it bears any resemblance to a Tesla turbine/pump: it looks like a pretty normal centrifugal pump to me. Could you explain what you are seeing that others are missing?

    Here's an example of a centrifugal blower with flat blades: http://www.nyb.com/Catalog/Bulletins/589.pdf

    Here's some flat pump impellers: http://www.marineengineparts.com/shopsite_sc/store/html/page310.html [Broken]
     
    Last edited by a moderator: May 5, 2017
  13. Aug 8, 2011 #12
    Do you believe that the water that is forced out of the spinning turbine will be replaced by water and air to fill the partial vacuum? Or will only air from the shaft be filling the partial vacuum and the spinning blades will then fling that air to the outer edge of the blades where it will contact the outside water and at that point mix with that water to form all those tiny air bubbles? I personally don't think the air has enough viscosity to develop the centrifugal force needed to go slamming into the wall of water on the outer edge of the spinning blades. I am more of the opinion that it is both air and water that continuously come in to fill a portion of the partial vacuum and the majority of the mixing action takes place within the area of the spinning blades. Please tell me if my reasoning is incorrect and how do you see it?
     
  14. Aug 8, 2011 #13
    jimhebert, you raise a good point. You are probably right that air and water are mixed prior to entering the turbine. The mixing and creation of small bubbles probably occurs mostly right in the entry of to the turbine (that's my guess). Water could be brought into the shaft by a hole, or series of holes, in the shaft. The mixing would start in the shaft, but I'm guessing the real mixing would occur in the turbulent region at the entry of the turbine.
     
  15. Aug 8, 2011 #14

    RonL

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    Russ, I'll retract my Tesla comments for the time being.

    My first thoughts were related to the lack of a housing and volute chamber, but the surrounding water functions as a housing. The close spacing of a large number of vertical triangle blades should impart the same basic transfer as flat horizontal disc plates.
    The bottom of the impeller looks to be a solid plate and the absence of water and air being sucked back into some port opening around the top side where shaft and impeller are joined, leaves me puzzled.
    In fact there is little to indicate some amount of suck-back, top or bottom.

    The air entrance holes can be seen at the top of the main shaft, just below the motor.

    I did find that VaraCorp, the sole distributor for the USA is in Austin, I'll see if I can get a unit or find a little better visual aid on the design.

    Your link to the marine impeller, is a positive displacement pump system, the other link was all volute style, then I thought of all the Amtek 1,2, and 3 stage vacuum cleaner units I have, they are flow through and do not have a volute design (the impellers are dead center inside the housing).

    Ron
     
    Last edited by a moderator: May 5, 2017
  16. Aug 9, 2011 #15
    Thanks to all of you for contributing. Later.
     
  17. Aug 9, 2011 #16
  18. Aug 9, 2011 #17

    RonL

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    Thanks for the link,
    There in frame 1, is a single hole visible, that should be the water intake.....there has to be an intake for the impeller to produce a flow.
    The holes for air and the 1, 2?, or 3? for water, I would think, produce a metering effect much like a carburetor on a internal combustion engine.

    Ron
     
  19. Aug 9, 2011 #18
    Are you referring to the hole on the shaft next to his thumb? If so, that is a hole that a pin slips into. There's a matching hole on the black piece also. Scroll down the page and watch 54 seconds into the video and he will insert the pin.
     
  20. Aug 9, 2011 #19

    RonL

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    Sorry:redface: the first time I looked the video did not appear, my scroll stopped at the bottom of the drawings.
    Guess I better throw in the towel, the only thing left that I can see is the shape of the blades produce a high and low pressure zone around the outer diameter.
    In one video there seemed to be a pulsing effect of air discharge ?

    Ron
     
  21. Aug 9, 2011 #20
    I agree it is weird how that thing works. Assuming that there is only air being sucked into the turbine area, then I see only 2 possible ways for a partial vacuum to be formed. One way may be by the centrifugal force produced by the blades thus expelling the air out into the water and leaving a partial vacuum behind. This seems very hard for me to conceive that these flat blades (not curved like a fan) could produce that kind of effect. The second possibility would be if the rapidly moving extreme outer edges of the blades produce at the point of contact with the still outside water, a venturi effect. I have never seen this type of venturi depicted in this way. This would be similar to holding or placing one end of a small plastic air line tube in the center stream of fast flowing water (garden water hose) such that the center line of the air tube is perpendicular to the water flow. Would a vacuum develop in the tube? I tried at my kitchen water faucet but didn't notice any vacuum in the tube. Maybe not enough water pressure in the faucet to produce a fast enough flow.
     
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