今天我们知道,对于同一飞机,其升力大小主要随飞行速度和迎角而变化。飞机以大速度飞行时,即使迎角很小,机翼也能产生足够的升力以克服重力维持飞行;如果飞机以小速度飞行,则必须配合较大的迎角。机翼才能产生足够的升力。但是,单纯用增大迎角的方法来提高低速度时的升力是有限度的——当迎角增大到临界迎角时,再继续增大迎角,气流就会在机翼上方后缘产生分离,机翼表面开始出现乱流,此时升力反而降低。然而飞机在起飞和着陆阶段,恰恰需要机翼在较小的速度下产生足够的升力,因此就有必要在机翼上安装增加升力的装置,这一需要为襟翼的产生埋下了伏笔。如果留心观察鸟类的飞行,就能够得到有趣的启示:鸟类翅膀 Today, we know that for the same aircraft, the size of the lift mainly depends on the flight speed and angle of attack. When the aircraft is flying at a high speed, the wing can generate enough lift to overcome the force of gravity to maintain its flight, even at a small angle of attack. If the aircraft is flying at a low speed, it must work with a larger angle of attack. The wings can generate enough lift. However, there is a limit to simply increasing the lift at low speeds by increasing the angle of attack - as the angle of attack increases to the critical angle of attack, the angle of attack continues to increase and the air flow rises above the trailing edge of the wing Produced separation, wing surface began to appear turbulent flow, lift at this time but reduced. However, during the take-off and landing phases of the aircraft, it is precisely the wing that generates sufficient lift at a relatively small speed. Therefore, it is necessary to install an apparatus for increasing lift on the wing, a need that paves the way for flaps. If you look closely at the flight of birds, you can get interesting inspiration: the wings of birds