Application of the relationship between gas velocity and pressure

For example, the wing of an airplane uses the relationship between gas velocity and pressure to create a pressure difference between the upper part and the lower part of the airplane, and atmospheric pressure makes the airplane rise.

For example, there is a speed reducer behind Citroen, which is also the relationship between gas flow rate and pressure. The purpose is to let the car press the car on the ground at high speed, so that the car is not easy to fly and cause traffic accidents.