The easiest way to understand the pressure reduction above an airfoil is to realize that the air is caused to travel in a curved pathadmin / April 14, 2019
The easiest way to understand the pressure reduction above an airfoil is to realize that the air is caused to travel in a curved path.
The important fundamental concept is inertia of the mass of the air.
When looking at the stationary Wing example, such as in a wind tunnel, the air would normally move in a straight path if the wing was not present. However, with the wing there, the air is caused to be pushed up over the top and then down behind the wing. This is a curved path which is an acceleration. Changing the velocity or direction of an air flow is an acceleration. Acceleration requires a force. The only Force we have is air pressure. Therefore, the pressure must be higher away from the wing and lower towards the wing causing the flow to curve. It is the mass and inretia of the air that tries to resist that curved flow and wants to go straight so the air in a sense is pulling away from the surface of the wing that’s lowering the pressure.