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Flow in a semi circular pipe

  1. Nov 25, 2008 #1
    Hi All:

    I am trying to calculate volumetris flow rate in a semi circular pipe with a fixed pressure but seem to have problems. I have calculated in a circular pipe as

    Q= (Pi (P1-P2) R^4)/8uL

    Can anyone comment on how to calculate for semi circular pipes?

  2. jcsd
  3. Nov 26, 2008 #2
    Q= (Pi (P1-P2) R^4)/8uL

    First of all: always write down what the symbols mean. Now I have to guess, and that's not helping. If I make a mistake (because I use other symbols because I live on another continent perhaps) we waste time.

    Assuming that
    Pi = 3.14 (-)
    P1 and P2 = pressure (Pa)
    R = radius (meter)
    u = Viscosity (Pa*s)
    L = length (meter)

    Then Q is the volumetric flowrate, in (m3/s), which seems correct.

    The next question is: what is "semicircular"?
    Does it mean that it was a round pipe (like almost all pipes) and that it's now flat on one side? Or did somebody put a bend of 180 degrees in a normal pipe?

    The pressure difference in a pipe depends on the wall-roughness, bends, flowrate (turbulent or laminar flow) and type of fluid, to name a few factors.

    I don't see enough information here.

    I'm sorry if I just made life more difficult, but I cannot simply give you the other formula like that... because I don't know it (I'd need more info!)
  4. Nov 26, 2008 #3

    I am sorry for not being clear.

    Yes you were right in assuming the symbols. The tube was circular but now its flat on one side - so you are right there also. We can assume steady state laminar flow. We are applying a constant pressure and can assume the tube to be smooth. There is no bend in the tube and we can have the answer in terms of "u - viscosity".

    Please let me know if you need any other information.

  5. Apr 20, 2009 #4
    Re: Flow in a semi circular pipe Heat Transfer

    Can Anyone please tell me what is the heat transfer coefficient for convection in a semi-circular pipe???
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