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Quick questions about Area-Velocity relation

  1. Feb 27, 2007 #1
    Is it valid for real gases? My initial thought would be no, since the derivation is based on the assumption that the flow is isentropic.

    Is it valid for square ducts?
  2. jcsd
  3. Feb 27, 2007 #2
    area velocity relation?

    the continuity equation?

    It can only be applied to incompressible flow, the density must remain constant.
  4. Feb 27, 2007 #3
    No, the area velocity relation is dA/A = (M^2 -1) dV/V
  5. Mar 3, 2007 #4
    hi piano girl-
    what is the M?-can u tell us about this equation more clear?,and please tell us which kind of gases this equation can be applied?-continuity equation cant be applied for the gases-its only as Mr:mybsaccownt said-for incompressible flow-and the gases is an compressible fluids-in which the density not constant.
    waiting you to tell us about this equation-it might be important,thanks .
    Last edited: Mar 3, 2007
  6. Mar 3, 2007 #5


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    M is mach number. I'd venture a guess that it is not terribly accurate if you needed good numbers for an experiment. However, I think that the results derive from it are useful.

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