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Old 19th Oct 2012, 19:43
  #166 (permalink)  
henra
 
Join Date: May 2010
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Originally Posted by peter kent
"As energy is not conserved the Bernoulli relation cannot be applied to airflow round a wing in flight."

Nobody else throws it out for this reason. It's a new one as far as I can tell.

Can you make any sense of it?
Interesting thought!
However the problem of energy conservation only significantly applies in the lower parts of the boundary layer of the wing. If you look at the speed and thus energy above the immediate boundary layer it will be close to the free stream air speed and thus you still have accelerated air speed and therefore reduced static pressure.
The streamlines above the boundary layer might not be perfect anymore and you might loose some lift compared to the theoretical lift with no boundary layer. But the general effect (Air accelerated creating low pressure and thus lift) will still be there.

Therefore my appreciation of this is that the effect described in the article might spoil the result of a calculation based on Bernoulli under ideal conditions but it does not prove that Bernoulli doesn't explain lift. At least my picture is not completely ruined (yet).

Last edited by henra; 19th Oct 2012 at 19:44.
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