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Homework Help: Continuity equation

  1. Apr 8, 2005 #1
    i do not understand how the continuity equation works?
     
  2. jcsd
  3. Apr 8, 2005 #2

    dextercioby

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    What continuity equation do you refer to?I can think of 2 or maybe more,but u need to be more specific.

    Daniel.
     
  4. Apr 8, 2005 #3
    that is the problem that i have ran into. on my assignment it does not say. it just ask us to use coninuity equation to explain how jet engines provide a forward thrust for an airplane? i have tried to research it but i am still lost.

    part 2 of the question ask us to use Bernoulli's equation and explain hoe it relates to continuity equation?
     
  5. Apr 8, 2005 #4

    dextercioby

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    This equation

    [tex] \frac{\partial\rho\left(\vec{r},t\right)}{\partial t}+\nabla\cdot\left[\rho\left(\vec{r},t\right)\vec{v}\left(\vec{r},t\right)\right]= 0 [/tex]

    Daniel.
     
  6. Jul 29, 2011 #5
    Hello, am study Continuity Equation right now for my problem Solving Class at ITT Tech
    The Continuity Equation was give in the book. A1V1=A2V2 where A1 is the cross-sectional area at point 1, V1 is the velocity of the fluid at point 1, A2 is the cross-sectional area at point 2, and then V2 is the velocity of the fluid at point 2. Like you I stuck on Skill Level Problem II about using the equation to explain how jet engines provide forward trust for an airplane.

    The Bernoulli's Equation and I still search for the equation but I think I end up using the one from Engineering Tool Box. The link is http://www.engineeringtoolbox.com/bernouilli-equation-d_183.html. I hope this helps but if you already finish maybe you can send help on the jet engine problem.
     
    Last edited by a moderator: Jul 31, 2011
  7. Jul 29, 2011 #6

    rock.freak667

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    The equation of continuity in fluid dynamics is used when a fluid flows through an area which is then changed. The total flow remains constant i.e. volume per unit time is constant.

    In equation form this is

    A1v1=A2v2

    How would A2 have to be with respect to A1 for there to be an increase in velocity?

    Loneliheart posted a link that should prove to be helpful.
     
  8. Jul 31, 2011 #7

    Redbelly98

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    This ol' thread is locked. (And by "old", I mean that literally.)
     
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