As we all know, what we breathe on the ground is a standard atmospheric pressure. The higher the air pressure is, the lower the density, the thinner the air is at a height of 10,000 meters, and the lower the temperature is, it is impossible for people to survive in this environment. But it’s different on the plane.
The engine room of the aircraft is strictly sealed. In this case, the aircraft will directly extract high temperature and high pressure air from the compression section of the engine, then automatically pressurize and then enter the air conditioning system of the aircraft. After air filtration, temperature and humidity regulation, etc., Release the proper fresh air into the engine room, and at the same time, it will drain out the unfresh air in the engine room to ensure that the air in the engine room is in good condition.
Because the cabin of the aircraft belongs to a thin-walled space structure, like a high-altitude balloon, the pressure difference between the inside and outside of the aircraft cannot be too large, which is also for the structural life of the aircraft. Therefore, when pressurizing the air, the cabin pressure will not be completely added to the same standard atmospheric pressure as on the ground, such as 0.2 atmospheres outside the 10,000 m altitude cabin and 0.8 atmospheres in the cabin, so passengers can also adapt to it.