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Old 20th Jul 2022, 07:21
  #40 (permalink)  
CliveL
 
Join Date: Dec 2010
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John,
I wasn't going to post anything as it has all been said, but since you ask:
Concorde, like many supersonic aircraft, has wings swept so that the flow normal to the LE is subsonic. That being so, the usual explanation fits, that is to say:-

An airfoil passing through a block of static air changes the state of that block in that some of it is left with a substantially downwards velocity

Newton tells us that to change something's state there must be a force applied

In this case that force is the mass flow affected per second times the incremental velocity

Newton can tell us nothing about the affected mass or the velocity, so is useless for calculating lift

Newton also tells us that every action (force) has an equal and opposite reaction

That reaction is the force we call lift acting on the airfoil

That’s Newton’s contribution

The magnitude of the force can most conveniently be calculated using the circulation hypothesis; Lift equals fluid density times circulation times velocity.

Circulation is effectively the strength of the vortex flows around the airfoil

Vortices can only be generated in a viscous fluid, and on a finite wing form a closed loop.

That loop is formed by vortices rotating around a spanwise axis (bound vortices), trailing (wingtip) vortices and way downstream, a starting vortex.

So much for lift generation

Force can only be applied to an object immersed in a fluid by changes in pressure of the fluid in contact with the body.

The distribution of those pressures and forces is best calculated using Bernouilli’s theorem

That covers Bernoulli

That's it really
CliveL is offline