Determining the coefficient of lift

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SUMMARY

The discussion focuses on a new method for determining the lift coefficient (CL) beyond the thin airfoil theory. The user proposes an equation where lift (L) is expressed as L = CL × 1/2ρv2A and attempts to relate it to mass (m) and upward acceleration (μ). However, the analysis reveals that during level flight, both upward acceleration and the acceleration term (a) become zero, leading to an undefined CL in this context. The conclusion emphasizes the need for a correct understanding of lift dynamics in steady flight conditions.

PREREQUISITES
  • Understanding of lift and drag forces in aerodynamics
  • Familiarity with the thin airfoil theory
  • Basic knowledge of algebra and physics equations
  • Concept of steady flight dynamics and acceleration
NEXT STEPS
  • Research the fundamentals of lift generation in various airfoil designs
  • Study the implications of the thin airfoil theory on lift coefficients
  • Explore the relationship between lift, drag, and thrust in steady flight
  • Learn about advanced aerodynamic models and computational fluid dynamics (CFD) simulations
USEFUL FOR

Aerospace engineers, physics students, and anyone involved in the study of aerodynamics and lift generation will benefit from this discussion.

Paradox101
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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?...please reply.
 
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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.
 
whoa...would've missed that,thanks!
 

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