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Here is a strange question for you. How is water affected by GPM, PSI, and Gravity.

  1. Dec 2, 2011 #1
    I'm trying to solve a theory I have on how a stream of water is affected by Gravity, GPM, Pressure and other factors, can anyone give me some guidance?

    The problem: I am trying to find a way to shoot a stream of water as far as possible at an angle of approximately 85 Degrees.

    The only things that I can think of that affects the distance I can shoot the stream of water besides wind and other acts of nature that I can't control are, pressure, the GPM flow of the water, The barrelling of the tip, the orafice size of the tip and the length of the tips barrel itself.

    If I am correct, which of these factors should I change, to increase the distance that I can shoot a stream of water using 3,500 PSI at 5.5 gallons of water per minute, since it's not possible to change the Gravity problem, the GMP or the PSI?

    The barrelling of the tip?
    The orafice size of the tip?
    The length of the tips barrel itself?

    Or is there something else that I've missed?
  2. jcsd
  3. Dec 2, 2011 #2
    Re: Here is a strange question for you. How is water affected by GPM, PSI, and Gravit

    The only thing that matters is the pressure. Although a larger orifice will produce larger water drops which will be less affected by wind resistance and will therefore travel further. The shape of the tip can determine whether the stream remains continuous or breaks up into drops.
  4. Dec 2, 2011 #3
    Re: Here is a strange question for you. How is water affected by GPM, PSI, and Gravit

    The water is flowing at 3,500 PSI and 5.5 gallons per minute, that's my only fixed variable in this problem. Changing the size of the tips, the length of the tips barell, or rifling it down are probably my only options that I have to work with that I can think of.

    Is there some kind of formulae that I could use to determine what the best sized orifice in the tip, along with the length of the tip, or any other variables I can change to be able to shoot a further distance, besides raising the pressure?

    I wonder if using a piece of 3/16" oe 1.8" diameter pipe about 12" long could help focus the beam of water into a tighter stream before it leaves the tip, allowing it to travel further before breaking up into a spray.

    Or what about using a piece of 1/4" pipe that shrinks down to a 3/16" opening?
  5. Dec 3, 2011 #4
    Re: Here is a strange question for you. How is water affected by GPM, PSI, and Gravit

    Turbulence of water will greatly affect cohesion of the stream post-confinement. You are shooting for laminar flow. The nozzle itself will be either a parabola or hyperbola shape with fine knife edge characteristics with pressured water not touching any part of the curve but only the X axis. Ω Take off the top half of this symbol and push water up thru it from the bottom and you are on track. The short straight part pipe at the bottom will create turbulence and so there should be a wide area below the nozzle and the water should only "see" the sharp edge of the bottom of the circle or parabola or hyperbola or whatever achieves experimental success with a very wide base as represented by the horizontal parts of the symbol but much longer. Laminar flow be the Holy Grail here and turbulence the enemy.

    This guy has done it but I don't see him using 3500 psi. Likely well under 100 psi. Be cautious with that much pressure for you can puncture skin. Seen it done with hydraulic fluid making a nice lump in a guys throat when a pinhole leak damn near got into a guy's carotid artery while he was working in the coal mine.

    This vid is not as pretty but has more relevant info to your query.
    Last edited by a moderator: Sep 25, 2014
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