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A Submerged water jet

  1. Apr 20, 2016 #1
    I am trying to calculate at what pressure and speed water from a high pressure water jet will hit an object 100 millimeters away from the nozzle opening, but i can't figure it out.

    The nozzle will be used at approximately 100 meter below sea level in salt water. Its a circular nozzle with a diameter = 2 millimeters. The water from the water jet is at 400 bar and with a flow of about 60 liters per minute.

    Does anyone know what formula to use?
  2. jcsd
  3. Apr 25, 2016 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Apr 25, 2016 #3


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    I don't think there is a simple formula where you could just plug in numbers. There are certainly publications about that setup, you could check what they did to simulate the system.
  5. Apr 26, 2016 #4


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    A turbulent jet of liquid discharged into a large volume of the same liquid spreads out in a cone shape . Tests and simulations have determined that assuming a half angle of 11.8 deg for the cone is adequate for most practical calculations . Problem is that the velocity of flow varies not only with distance from nozzle but also with radial distance from the flow centreline . Velocity is highest on the flow centreline and fades away to zero at larger radial distances .

    What actually happens when jet impinges on an object depends on the geometry of the object .
  6. Apr 26, 2016 #5


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    This becomes doubly difficult if your water jet is fresh water discharging into salt water, as it is now a turbulent buoyant jet. Generally speaking there is no simple solution to this problem (buoyant or not).
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