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« on: February 13, 2018, 10:28:21 PM »
Aravind298
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Greetings to all,

There's been a lot of misconceptions around how lift is generated from an aerofoil.

I, myself was taught at school, the most used theory, explained wrongly using Bernoulli's theorem; which is the 'equal time argument' theorem.
I've attached a few videos which greatly explains the theory. So, spend some time watching it, and trust me, it's worth it.





Why equal time argument is wrong:

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« Reply #1 on: February 13, 2018, 10:30:38 PM »
Aravind298
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Here's a much more intuitional video, which projects the air flow:



Hope that helps   Hats Off
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« Reply #2 on: February 14, 2018, 09:20:58 AM »
Imperial fire
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Keep calm and fly safe.



Man I've spent so much time on just airfoils...
And cloned so many on balsa wood and made airplanes so many times...I can say from experience that the Bernoulli's theorem is so incomplete.....
In the end I've concluded..
An airplane flies by displacing air...just like a boat does in water to stay afloat....
The only difference is that since air is a less dense fluid...an airplane must ' actively,', displace it's fluid to stay  'afloat'..
Just my little theory...

This guy on YouTube called samm Shepard also as some interesting experiments on stall angle of wings etc
So much more to this hobby than how others see it as me ' playing with a toy'
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« Reply #3 on: February 14, 2018, 09:39:14 AM »
Aravind298
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Bernoulli's theorem, is by no means, incomplete. We just fail to put the necessary boundary conditions required for it to work properly.

The equal time argument is absurd; since Bernoulli's theorem is applied to a single streamline. Whereas, in this argument, it is used in two different streamlines.

Bernoulli was a good guy dude Grin , at least, according to me.
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« Reply #4 on: February 14, 2018, 09:40:38 AM »
Aravind298
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So much more to this hobby than how others see it as me ' playing with a toy'

Yeah. People fail to understand the 'why' behind the hobby. They assemble it, fly it, throw it away. No offense, but people can really pay some time to know how it works.
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« Reply #5 on: February 14, 2018, 09:48:25 AM »
Imperial fire
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' Bernoulli's theorem, is by no means, incomplete'
I meant incomplete in explaining lift generation ...
2 particles have no reason to meet again...infact 2 particles could diverge never to meet again in their lifetime.... 
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« Reply #6 on: February 14, 2018, 10:20:00 AM »
Aravind298
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I meant incomplete in explaining lift generation ...


Didn't get you. Could you be a bit more specific? Examples are appreciated Smiley
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