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Determining the coefficient of lift

  1. Dec 17, 2014 #1
    Been working on a new way of determining the lift coefficient besides the thin airfoil theory,and I don't know if there is already such a method or if i'm wrong.Plz Help.We know,
    L=CL×1/2ρv^2A
    Now,as lift is a force,then it should be as L=mμ, where μ is the "upwards acceleration".
    So, L=mμ=CL×1/2ρv^2A
    ⇒mμ=CL×1/2ρ[(0)^2+2as]A, because v^2=u^2+2as,and here the initial velocity will be zero.
    ⇒mμ=CL×1/2ρ2asA
    ⇒mμ=CL×ρ×a×s×A
    ⇒CL=mμ/ρasA
    That's it.Am I wrong somewhere?......plz reply.
     
  2. jcsd
  3. Dec 17, 2014 #2

    boneh3ad

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    I suppose the algebra seems correct, but I am not really certain that this would ever be useful. For level flight, there isn't going to be any acceleration upward or downward since ##ma = \Sigma F## and ##\Sigma F## will be zero, yet there is certainly still lift. In other words, your ##\mu## is likely going to be meaningful. Further, for level flight at constant airspeed, your ##a## term will also be zero, meaning your whole ##C_L## will have a ##0/0## term in it and will be undefined, yet ##C_L## is certainly defined and nonzero at that point.
     
  4. Dec 18, 2014 #3
    whoa.....would've missed that,thanks!
     
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