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Which is more efficient, thickening an airfoil or adding a bottom-surface curve?

You were doing fine until you threw in "supercritical airfoils". Now we have to go over all 130 years of modern aviation. A bit much for one question but ... Yes, adding undercamber will ...
Robert DiGiovanni's user avatar
3 votes

Which is more efficient, thickening an airfoil or adding a bottom-surface curve?

So if you were to take a standard airfoil and increase the thickness, you’d increase the lift No, you don't. Lift is determined by camber and angle of attack. Both don't change with thickness, so ...
Peter Kämpf's user avatar
2 votes

Which is more efficient, thickening an airfoil or adding a bottom-surface curve?

So if you were to take a standard airfoil and increase the thickness, you’d increase the lift. This is true only till around 12% thickness, afterward the $C_{l_{max}}$ decreases with increasing ...
sophit's user avatar
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1 vote

Which is more efficient, thickening an airfoil or adding a bottom-surface curve?

Adding thickness doesn't add lift. Don't cite Bernoulli's principle and Newton's 3rd law as causal in an aerodynamics discussion -- everything is far more complex and nuanced than that. You can't add ...
Rob McDonald's user avatar
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0 votes

Conundrum about designing a glider relating to coefficient of lift

I would start with Reynolds number and evaluate your anticipated speed envelope. The wing you have chosen is good for low Re number aircraft. Why not use the same airfoil for you horizontal ...
Robert DiGiovanni's user avatar
3 votes

Conundrum about designing a glider relating to coefficient of lift

To start with, you can ignore changes due to compressibility (Mach number) and viscosity (Reynolds number). Your aircraft will have a drag polar approximately of the form: $C_D=C_{D,0}+K\,{C_L}^2$ You ...
Rob McDonald's user avatar
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1 vote

Conundrum about designing a glider relating to coefficient of lift

However, something that does change the coefficient of lift is the AoA, which is determined from Reynolds number. The AoA is determined solely by the relative angle between the lifting surface and ...
sophit's user avatar
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0 votes

Lift distribution of a swept wing with twist, dihedral, taper

The lift coefficient Cl is linear with angle of attack. Twist is extra angle of attack. For every section of the wing dx, you're reducing lift relative to wing twist. Schrenk's method has provisions ...
Josh Carr's user avatar
0 votes

Lift distribution of a swept wing with twist, dihedral, taper

I am trying to get the lift distribution of a swept wing with taper (in chord and thickness along the span), twist, and dihedral. The change in spanwise lift distribution due to taper ratio, twist, ...
sophit's user avatar
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2 votes

Lift distribution of a swept wing with twist, dihedral, taper

The easiest way (I believe) will be to run a simple VLM aerodynamic analysis. For this, I suggest you use OpenVSP and VSPAERO. Dihedral won't change the lift distribution in a significant way (in ...
Rob McDonald's user avatar
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2 votes
Accepted

In which position does Starship wings produce the most drag?

In the subsonic re-entry phase, Starship is basically falling free from the sky laying on its belly with the forward (upper) and rear (lower) fins stabilising the free fall and keeping it parallel to ...
sophit's user avatar
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3 votes

In which position does Starship wings produce the most drag?

Because the Starship falls horizontally you are correct to have Cdrag rather than Clift in your equation. Based on coefficient of drag shapes here, having the fins canted down may produce more drag, ...
Robert DiGiovanni's user avatar
0 votes

How do wings generate lift?

This is a very instructive article published in 'The Physics Teacher' (Vol. 36. Nov. 1998). It includes mathematical derivations and a numerical example: https://i.stack.imgur.com/YRgY5.jpg https://i....
xxavier's user avatar
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