一、机翼升力原理

1、 Wing lift principle

如果两手各拿一张薄纸，使它们之间的距离大约4~6厘米。然后用嘴向这两张纸中间吹气，你会看到，这两张纸不但没有分开，反而相互靠近了，而且用吹出的气体速度越大，两张纸就越靠近。从这个现象可以看出，当两纸中间有空气流过时，压强变小了，纸外压强比纸内大，内外的压强差就把两纸往中间压去。中间空气流动的速度越快，纸内外的压强差也就越大。

If you hold a thin piece of paper in each hand, make the distance between them about 4 ~ 6cm. Then blow air between the two sheets of paper with your mouth. You will see that the two sheets of paper are not separated, but close to each other. Moreover, the greater the speed of the most blown gas, the closer the two sheets of paper are. It can be seen from this phenomenon that when air flows between the two papers, the pressure becomes smaller, the pressure outside the paper is greater than that inside the paper, and the pressure difference between the inside and outside presses the two papers to the middle. The faster the middle air flows, the greater the pressure difference inside and outside the paper.

飞机机翼地翼剖面又叫做翼型，一般翼型的前端圆钝、后端尖锐，上表面拱起、下表面较平，呈鱼侧形。前端点叫做前缘，后端点叫做后缘，两点之间的连线叫做翼弦。当气流迎面流过机翼时，流线分布情况如图2。原来是一股气流，由于机翼地插入，被分成上下两股。通过机翼后，在后缘又重合成一股。由于机翼上表面拱起，是上方的那股气流的通道变窄。根据气流的连续性原理和伯努利定理可以得知，机翼上方的压强比机翼下方的压强小，也就是说，机翼下表面受到向上的压力比机翼上表面受到向下的压力要大，这个压力差就是机翼产生的升力。

The ground wing section of an aircraft wing is also called an airfoil. Generally, the front end of the airfoil is round and blunt, the rear end is sharp, the upper surface is arched, and the lower surface is flat, showing a fish side shape. The front point is called the leading edge, the rear point is called the trailing edge, and the line between the two points is called the chord. When the air flows head-on through the wing, the streamline distribution is shown in Figure 2. It turned out to be a stream of air, which was divided into upper and lower streams due to the insertion of the wing. After passing through the wing, it reconstitutes a strand at the trailing edge. Because the upper surface of the wing is arched, the channel of the air flow above is narrowed. According to the continuity principle of air flow and Bernoulli's theorem, the pressure above the wing is smaller than that below the wing, that is, the upward pressure on the lower surface of the wing is greater than the downward pressure on the upper surface of the wing. This pressure difference is the lift generated by the wing.

二、飞机机的翼阻力

2、 Wing resistance of aircraft

只要物体同空气有相对运动，必然有空气阻力作用在物体上。作用在模型飞机上的阻力主要有摩擦阻力、压差阻力和诱导阻力。

As long as the object moves relative to the air, there must be air resistance acting on the object. The resistance acting on the model aircraft mainly includes friction resistance, differential pressure resistance and induced resistance.

摩擦阻力：当空气流过机翼表面的时候，由于空气的粘性作用，在空气和机翼表面之间会产生摩擦阻力。如果机翼表面的边界层是层流边界层，空气粘性所引起的摩擦阻力比较小，如果机翼表面的边界层是紊流边界层，空气粘性所引起的摩擦阻力就比较大。

Friction resistance: when air flows through the wing surface, due to the viscous effect of air, friction resistance will be generated between the air and the wing surface. If the boundary layer on the wing surface is a laminar boundary layer, the friction resistance caused by air viscosity is relatively small. If the boundary layer on the wing surface is a turbulent boundary layer, the friction resistance caused by air viscosity is relatively large.

为了减少摩擦阻力，可以减少模型飞机同空气的接触面积，也可以把模型飞机表面做光滑些。但不是越光滑越好，因为表面太光滑，容易保持层流边界层，而层流边界层的气流容易分离，会使压差阻力大大增加。

In order to reduce the friction resistance, the contact area between the model aircraft and the air can be reduced, and the surface of the model aircraft can also be made smoother. However, the smoother the better, because the surface is too smooth, it is easy to maintain the laminar boundary layer, and the air flow in the laminar boundary layer is easy to separate, which will greatly increase the differential pressure resistance.

以上的精彩内容是 大型航空模型制作为您提供，我们保证质量，价格合理，力争给顾客带来优质的服务，更多的精彩内容请继续关注我们的网站：http://www.quanyimoxing.com

The above wonderful contents are provided for you by large-scale aviation model production. We guarantee the quality and reasonable price, and strive to bring high-quality services to customers. For more wonderful contents, please continue to pay attention to our website: http://www.quanyimoxing.com