Cl/Cd equations

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The discussion revolves around a derivation from Warren F. Phillips' book on flight mechanics, specifically concerning the lift-to-drag ratio (C_L/C_D). The user is struggling to reconcile their results with the expected outcome from the equations provided. They present a series of equations and transformations but end up with a different expression for C_L/C_D. The key confusion seems to stem from the manipulation of terms and the application of the equations. Clarification on the derivation process and potential algebraic errors is sought to resolve the discrepancy.
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cant figure it out equations
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Hi, im studying flight mechanics from the book of Warren F Phillips, in a derivation is saying that from the first two equations we can derive the third one but i obtain something different entirely. What am i missing? thanks
 
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$$C_L = \sqrt{C_{D_0}\pi e R_A} = \sqrt{C_{D_0}}\sqrt{\pi e R_A}$$
$$\frac{C_L}{C_D} = \frac{\sqrt{C_{D_0}}\sqrt{\pi e R_A}}{C_{D_0} + C_{D_{0,L}} \sqrt{C_{D_0}}\sqrt{\pi e R_A} + \frac{C_{D_0}\pi e R_A}{\pi e R_A}}$$
$$\frac{C_L}{C_D} = \frac{\sqrt{C_{D_0}}\sqrt{\pi e R_A}}{2C_{D_0} + C_{D_{0,L}} \sqrt{C_{D_0}}\sqrt{\pi e R_A}}$$
$$\frac{C_L}{C_D} = \frac{\sqrt{C_{D_0}}\sqrt{\pi e R_A}}{2C_{D_0} + C_{D_{0,L}} \sqrt{C_{D_0}}\sqrt{\pi e R_A}} \times \frac{\frac{1}{\sqrt{C_{D_0}}}}{\frac{1}{\sqrt{C_{D_0}}}}$$
$$\frac{C_L}{C_D} = \frac{\sqrt{\pi e R_A}}{2\sqrt{C_{D_0}} + C_{D_{0,L}} \sqrt{\pi e R_A}}$$
 
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Many Many thanks!!!
 
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Due to the constant never ending supply of "cool stuff" happening in Aerospace these days I'm creating this thread to consolidate posts every time something new comes along. Please feel free to add random information if its relevant. So to start things off here is the SpaceX Dragon launch coming up shortly, I'll be following up afterwards to see how it all goes. :smile: https://blogs.nasa.gov/spacex/
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