Linked Questions
13 questions linked to/from Why do wall-to-wall airfoils in wind tunnels produce no (or infinitesimal) downwash?
36
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3
answers
13k
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How does an aircraft form wake turbulence?
This question discusses how wake turbulence can affect planes flying in formation. It got me wondering, how do aircraft (the wings in particular) form wake turbulence to begin with? It can't be as ...
- 24k
17
votes
4
answers
10k
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How high does the ground effect last?
Up to which height is the ground effect still significant enough to be taken into account? Would this height be sufficient to actually fly above the ground, overcoming at least trivial obstacles like ...
- 12k
9
votes
5
answers
2k
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Can wing-tip vortices be reduced/eliminated with a rear-facing propeller near the wing-tip?
Let's say we have a propeller-driven aircraft in the pusher configuration (rear-facing propellers). If we could somehow put an engine at the wing tip (ignoring structural concerns), and maybe make the ...
- 17.6k
11
votes
3
answers
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Does the downwash created by induced drag increase or decrease lift?
According to the theory I know, lift is produced by accelerating air downwards at the trailing edge (downwash). Hence, as downwash increases so does lift. Induced drag is due to vortices at the wing ...
- 741
9
votes
3
answers
4k
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Is induced drag essentially nothing more than a specific type of form drag?
If I were standing outside on a windy day holding a flat rectangular object such as a food tray up in the wind, orthogonal to the direction of flow, the drag created would be classified, mostly, as ...
- 8,761
11
votes
2
answers
8k
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Why does the vortex created by wing affects its own angle of attack?
According to potential flow theory, we know that the lift generated by the wings is due to the vortex it creates. In case of a 3D finite wing, there is also a span wise flow due to tip leakage from ...
- 559
12
votes
2
answers
6k
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How is the induced drag calculated for a wing with elliptical planform?
How is the induced drag calculated for a wing with elliptical planform ? Is this wing shape the most efficient ?
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6
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2
answers
4k
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Why is induced drag less on a high span wing?
I have a basic question and sorry if it is a well known fact.
I understand that the induced drag is due to the tip vortices changing the effective angle of attack (downwash).
I searched some ...
- 741
8
votes
1
answer
836
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Do software simulations and wind-tunnel tests accurately predict Cd and Cl in real-world conditions?
Will the lift coefficient (Cl) and drag coefficient (Cd) I obtain by using software simulations or subsonic wind-tunnel tests be the same as on an actual aircraft while cruising? Or will there be some ...
1
vote
2
answers
3k
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How does wing aspect ratio influence lift and drag?
I know simmilar questions are all over the internet (and this website too), but there's one thing that i just cannot comprehend and none of the articles i read could explain it properly.
According to ...
- 113
0
votes
2
answers
3k
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Will 3D wing has smaller drag than 2D at same AoA and airflow speed?
We meassure lift and drag for 2D and 3D wing case,we use same airfoil at same AoA and same airflow speed for both case.
Wind tunnel can change test section walls width.
2D wing test:
So first we put ...
- 177
1
vote
1
answer
547
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Why does each part of span not produce equivalent downwash?
I know that it is associated with Prandtl lifting-line theory and that ideal elliptical wing actually meets the condition of my question. Unfortunately I am not good at fluid dynamics and I would like ...
1
vote
1
answer
397
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Why is subsonic lift at 25% of chord? [duplicate]
I pretty much understand the way a wing works and the different ways of explaining it, what I don´t understand is why the lift on a subsonic wing manifest itself at the 25% chord....
The 50% chord ...
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