So for people who fly, it is better to say "bon voyage" than "bon voyage". If he is a foreigner, I wish him a happy landing!
Extended data:
Aircraft flight principle:
In the ideal gas or when the wing just started to move, this condition was not met and the viscous boundary layer did not form. Generally speaking, the upper distance of airfoil (wing cross section) is longer than the lower distance. At first, the airflow speed on the upper and lower surfaces is the same, and there is no circulation, so when the lower airflow reaches the trailing edge point, the upper airflow does not reach the trailing edge, and the stagnation point is located at a point above the airfoil, so the lower airflow must bypass the sharp trailing edge and join the upper airflow.
Due to the viscosity of the fluid (that is, Kangda effect), when the lower airflow bypasses the trailing edge, a low-pressure vortex will be formed, and a large reverse pressure gradient will be generated at the trailing edge. Immediately, this vortex will be washed away by the incoming current, and this vortex is called the initial vortex. According to Helmholtz vortex conservation law, under the action of ideal incompressible fluid, a vortex with the same intensity and opposite direction will appear around the airfoil, which is called circulation or circulation around the airfoil.
The circulation flows from the leading edge of the upper surface of the wing to the leading edge of the lower surface, so the stagnation point will eventually move back to the trailing edge of the wing, thus satisfying the Kutta condition. The circulation around the wing caused by satisfying Kutta condition leads to the backward acceleration of the upper surface airflow of the wing. According to Bernoulli theorem, the pressure difference can be deduced and the lift can be calculated. The final lift generated by this circulation can also be calculated by Kutta-zhukov equation: L (lift) = ρ v γ (gas density× flow velocity× circulation value), and the aerodynamic force of Magnus effect can also be calculated.
Precautions for flight:
Prevent airsickness. Airsickness and vomiting are due to the disorder of balance organs and poor physical adaptability. Generally, as long as you keep calm, get rid of other thoughts and take some medicine to prevent carsickness, you will be safe. If you know that you may get airsick, you'd better take the medicine 15 minutes before boarding.
The effective measure to prevent aviation otitis media is to swallow with your mouth open. Chewing is the most effective way to prevent aviation otitis media. If the symptoms are still not eliminated, you can hold your nose with your thumb and forefinger, close your mouth, and exhale forcibly, so that the airflow will flush the eustachian tube into the air cavity of the middle ear to eliminate symptoms such as stuffy ear, heavy ear, earache and discomfort.
References:
Aircraft-Baidu Encyclopedia