Determining the coefficient of lift

  • #1
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1

Main Question or Discussion Point

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.
 

Answers and Replies

  • #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.
 
  • #3
47
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whoa.....would've missed that,thanks!
 

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