Why does a fluid follow the wing

aircraftflowfluid dynamicspressure

When air is moving above and under a wing that is curved, why does the air at the top of the wing follow the wings shape and go downwards when it could just go in a straight line? It doesn't make sense to me.

Best Answer

The air above the wing is accelerated down towards the wing by the air pressure from the air further above

Related Solutions

[Physics] How to airplanes fly upside down

Upside-down or right side up, flight works the same way. As you stated, the wing deflects air downward. When inverted, the pilot simply controls the the pitch of the aircraft to keep the nose up, thus giving the wings sufficient angle of attack to deflect air downwards.

Most airplanes are designed with some positive angle of attack "built-in," meaning that there is some angle between the wings and the fuselage so that the wings have a small positive angle of attack while the fuselage is level. This is why the floor isn't tilted tailwards when you're in an airliner in level flight. So when upside down the nose has to be held a bit higher than usual, and the other flight systems (including the pilot!) must be designed to handle it, but there is nothing really special about upside-down flight.

[Physics] Why does the higher pressure of air underneath an aeroplane wing keep it flying

First thing, that's a common misconception that the plane flies due to the Bernoulli effect.

See the these questions: What really allows airplanes to fly? Why does the air flow faster over the top of an airfoil? for the correct explanation.

Assuming that the bernoulli effect does explain flight, the answer to your question is:

Pressure of a fluid is force exerted by a fluid on a unit area of a neighboring body (the force exists inside the fluid as well, but it is balanced). So, if there is more pressure underneath, the upward force is greater (area if top and bottom of wings are approximately the same)

If the upward force is greater, the net force due to pressure is upwards. This force is called 'lift', and it balances gravity, helping the plane fly.

Read http://enwp.org/Pressure for more info.

Best Answer

Related Solutions

[Physics] How to airplanes fly upside down

[Physics] Why does the higher pressure of air underneath an aeroplane wing keep it flying

Related Question