Bernoulli's Principle, Busted?
- Thread starter SpiceWeasel
- Start date
texas_pilot
Well-Known Member
Correct, but further defination is clarified by the relation of thickness of the wings leading edge:
the thinner the leading edge is inverse to the operating costs.
inigo88
Composite-lover
Cambridge University professor lectures on common misconceptions of lift:
Last 5 min summary: Bernoulli's equation is Newton's 2nd law derived for flow along a streamline. The vertical distance between adjacent streamlines is what causes pressure changes (bunch them up = lower pressure). Lift is caused by putting an object into the flow which produces flow curvature, and hence causes the streamlines to bunch up. Like I said in my previous post, the overall pressure distribution below and above the wing creates lift... but the upper surface contributes 60% or more of that force. The Kutta-Joukowski Theorum for a rotating 2D cylinder that I talked about previously does the same thing with a rotating cylinder. If the cylinder is standing still, it acts like a symmetric airfoil. If you put a spin on it, it creates flow circulation, which creates lift.
NASA explains it all here: http://www.grc.nasa.gov/WWW/k-12/airplane/cyl.html
And if you don't have the patience to watch an academic lecture, here's a hipster explaining it in 2 minutes:
Last 5 min summary: Bernoulli's equation is Newton's 2nd law derived for flow along a streamline. The vertical distance between adjacent streamlines is what causes pressure changes (bunch them up = lower pressure). Lift is caused by putting an object into the flow which produces flow curvature, and hence causes the streamlines to bunch up. Like I said in my previous post, the overall pressure distribution below and above the wing creates lift... but the upper surface contributes 60% or more of that force. The Kutta-Joukowski Theorum for a rotating 2D cylinder that I talked about previously does the same thing with a rotating cylinder. If the cylinder is standing still, it acts like a symmetric airfoil. If you put a spin on it, it creates flow circulation, which creates lift.
NASA explains it all here: http://www.grc.nasa.gov/WWW/k-12/airplane/cyl.html
And if you don't have the patience to watch an academic lecture, here's a hipster explaining it in 2 minutes:
Last edited:
DBrown
Well-Known Member
Oh man, too easy.
My poor attempt a humor
Should have gone low brow
"Sept fer Lernin dem some lift"
darrenf
resident denizen
I thought for a second it might have been. Couldn't pass the opportunity to take a shot though.
It's the internet. We all type in the same font, type at the same volume and the Emo Phillips running off at the mouth about Astrophysics looks, at first glance, just as compelling as Neil DeGrasse Tyson's. Tyson sees question his view as a challenge, Phillips gets mad and wants to "take his ball and go home" because he feels he's being shot down.
Sometimes he is being shot down because Tyson is "the man on the subject".
Just like when I got "A.Netted" in a discussion on the MD-88 years ago. Sorry son, but all the Microsoft Flight Simulator in the world doesn't amount to a hill of beans when it comes to how it really works and, after a while, either I'll grow tired of getting "yeah but"'ed on the issue or seek to entertain myself.
Sometimes he is being shot down because Tyson is "the man on the subject".
Just like when I got "A.Netted" in a discussion on the MD-88 years ago. Sorry son, but all the Microsoft Flight Simulator in the world doesn't amount to a hill of beans when it comes to how it really works and, after a while, either I'll grow tired of getting "yeah but"'ed on the issue or seek to entertain myself.
