- #1
blainiac
- 50
- 2
Hello,
I wish to begin by stating I appreciate all feedback and the time taken to answer my inquiry. I have read high and low. I have a general understanding of lift (not well developed), and have read many articles on Bernoulli vs. Newton, circulation theory, Coandă effect, Magnus effect, etc.
To start my inquiry off, I have found a patent that discusses what I am talking about, using 'recycled' moving air to create a pressure difference on one side of a shroud (http://www.freepatentsonline.com/6729839.html). The patent described is for vacuum cleaning, multi-surface suction, etc. The basic idea is to connect the intake and outtake of a centrifugal fan to create a pseudo vortex, with one part of a shroud open (the side you wish to have a pressure difference). I have also played with some Navier-Stokes simulations and confirmed that there is a lower pressure on the open end.
My inquiry is, if on one side the device has a lower pressure, and atmospheric pressure is on the opposite side, is there a force (of the entire 'machine') in the direction of the open part of the shroud? With the simulators, it shows the device sucking particles as expected (with a low pressure on the surface in question), but how does Newton come into play here? Could someone explain how there could be a force (if any) with the lower pressure in that region if the device was not near a surface (such as a force in the direction of the opening)? Would rotating the round surfaces produce a noticeable difference in pressure (as per Magnus effect (or does this only apply to a free stream))?
I've tried looking at the problem as a sum of all forces acting on the surfaces, but it's quite difficult.
Once again, I am ignorant on these matters, but very interested and will do the work to understand. Thank you VERY much for your answers.
I wish to begin by stating I appreciate all feedback and the time taken to answer my inquiry. I have read high and low. I have a general understanding of lift (not well developed), and have read many articles on Bernoulli vs. Newton, circulation theory, Coandă effect, Magnus effect, etc.
To start my inquiry off, I have found a patent that discusses what I am talking about, using 'recycled' moving air to create a pressure difference on one side of a shroud (http://www.freepatentsonline.com/6729839.html). The patent described is for vacuum cleaning, multi-surface suction, etc. The basic idea is to connect the intake and outtake of a centrifugal fan to create a pseudo vortex, with one part of a shroud open (the side you wish to have a pressure difference). I have also played with some Navier-Stokes simulations and confirmed that there is a lower pressure on the open end.
My inquiry is, if on one side the device has a lower pressure, and atmospheric pressure is on the opposite side, is there a force (of the entire 'machine') in the direction of the open part of the shroud? With the simulators, it shows the device sucking particles as expected (with a low pressure on the surface in question), but how does Newton come into play here? Could someone explain how there could be a force (if any) with the lower pressure in that region if the device was not near a surface (such as a force in the direction of the opening)? Would rotating the round surfaces produce a noticeable difference in pressure (as per Magnus effect (or does this only apply to a free stream))?
I've tried looking at the problem as a sum of all forces acting on the surfaces, but it's quite difficult.
Once again, I am ignorant on these matters, but very interested and will do the work to understand. Thank you VERY much for your answers.
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