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berridos

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I am reviewing a paper that fits very well my current interests:
1595838414383.png
Would somebody shed some light on the excerpt below and the concept of induced camber? Maybe an explanation that would be understandable for kids would be very appreciated.
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pwood66889

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Top-of-the-head, and not going to a "Full-Calculus Press," I'd say get the figure next to the verbiage! Then you have to point out where (a) is an idealized flow, where none of the air escapes around the tips of the wings. Note that (b) being more the case encountered in "real life."
My thinking is that "induced camber" is the change in difference between top and bottom surfaces. Kinda hard to grasp unless you follow the air in the mind's eye. "Streamline curvature" is the tightness of the vortex swirls. The English used in the paper suggests to me they mean the same thing.
My review of this paper would point out its incomprehensible-ness! Perhaps it is the aging brain I possess that keeps me from remembering what was said by the time I get to what is drawn. And it is past my bed time!
 

Sockmonkey

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I've noticed that a lot of technical subjects suffer from a big gap between children's book and expert level.
Explaining stuff clearly to non-experts is a skill of it's own.
 

BJC

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If a person is unable to explain a technical subject, then he does not understand that subject.


BJC
 

pwood66889

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Ah, but the OP is trying to understand, and needs better verbiage BJC.
I stand by my criticism. The drawing next to the section that discusses it makes it clear what is going on. By looking at the roll of the air off of a finite lengthed wingspan, I can see the curvature of it expand. That should help.
 

berridos

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My intuition matches your interpretation regarding the term induced camber, based on other papers that showed the S path the airflow follows over the upper surface.
But i really still have a hard time understanding without pictures the adverse pressure gradient mentioned that produces leading edge stall with low AR. On the other hand that adverse pressure gradient could be the root pheanomenon for vortex lift.
I need coloured pictured like the little kids. Sesam street should devote an episode to vortex lift.
 

pwood66889

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Breaking it down, Berridos. "Adverse" means bad, so the pressure gradient is not going in a good direction. A "Gradient" is a rate of change; kinda like the steepness of a hill. So to me, "adverse pressure gradient" means the air pressure is not going a way one would like. But that could be just the physics of the situation. Where is this occurring?
 
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