Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Ball in pipe turbulant problem

  1. Oct 30, 2011 #1
    Hello

    I have a vertical pipe with floating ping pong ball in it.

    I have fan at the bottom that that push the ball up.

    The pipe parameters:
    D=45mm
    L=1.07m

    Ball parameters:
    D=40mm
    M=2.7g

    I tried to change fan speed to move the ball but becouse turbulance the ball is not steady, and so I can not control ball hight with fan speed.

    I installed step motor at the top to open and close the hatch, it seems to be working.

    I have now problem to calculate all of it.

    If I look at the ball that floats in the air (inside the pipe) , the forces that I believe are effecting the ball are:
    fg-weight force (down)
    fd-drag force (up)
    fb-buoyant force (up)

    And I believe that there is a some turbulance force that pulls the ball down.

    I cant use stocks equations becouse Re number is more than 2300 and I cant use bernoulli equations also becouse I have turbulance.

    Eventually I need somehow to calculate the pressures ratio between two sides of the ball,

    and develop formula for ball's hight.

    Please help with this.
     
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted



Similar Discussions: Ball in pipe turbulant problem
  1. Limit of Turbulence (Replies: 4)

  2. Mass of turbulence (Replies: 2)

Loading...