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Lifting capacity of the aircraft
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Lifting capacity of the aircraft

Lifting capacity of the aircraft

 

lifting capacity- One component of the total aerodynamic force that is perpendicular to the velocity vector of body motion in the flow of liquid or gas, the resulting asymmetry of the flow stream of the body.

Lifting capacity of the aircraft 1 schemeBernoulli empirically found that the static pressure in the flow of liquid or gas flow rate inversely at this point, which means that at the points where the flow rate the higher the pressure - below. In practice, it is easier to understand this expression as an example: when at the entrance to the escalator great pandemonium of people formed at the metro station, there is a crush (front of an escalator), and when you walk on the escalator and begin to climb, then on stage is worth a maximum of 2 man and the speed of your movement above, and m. n. "Overcrowded" (pressure) below.

So "works" and the liquid in the tube of variable cross-section. Now, mind you can imagine that this pipe "deployed" and spread out on the surface of 2 like an airplane wing. One (upper) has a greater curvature (bulge), and the bottom has a lower bulge (virtually flat). Thus we obtain, according to the equation of continuity of fluid flow stream (or gas) has clear physical phenomenon - the pressure difference between the top and bottom of the wing. We find that on the lower surface of lower flow rate and static pressure is higher, and on top of the lower static pressure (b.p. flow rate is greater due to geometric difference in length). This is a simple explanation for the classic wing profile and an infinitely large magnitude.

 

Calculation of wing lift.Zhukovsky theorem on lift force.

 

In the life of a wing to make unrealistic. Therefore, we apply the mathematical properties to solve this problem: the final scope, the normal vector to the profile, the profile of the boundary, the magnitude of the pressure, we obtain the following expression:

Lifting capacity formula

Lifting capacity formula 2

 

Lifting capacity of the aircraft wing

 

People who start their acquaintance with aviation or it may continue to have mature question, again all all knew, were outstanding and the opening of minds, but the plane was able to fly only 1903 year, what's the deal? And here's the thing: it could make its maiden flight before, but for a long time, scientists were confused how to calculate the lift and what should be the wing of the aircraft, its length?

 

Lifting capacity of the aircraft 1 scheme

 

According to classical physics of Newton and in accordance with the laws of the lift it is proportional to the angle of attack in the second degree, which led to the conclusion that it is impossible to make a small wing span with good load-bearing characteristics. We can imagine the usual parabola, y = x2 and we see that, for example, to lift equal to 2 need to reach an angle of attack in 4, and for a good flight and need to lift in 4, 5, 6 ... sometimes difficult to calculate attack angleAnd if he still will be in the critical zone ...

This confusion continued until the end of the century, 19, already Bernoulli only after many experiments and many other scientists, it was found that this dependence - (!) Straightforward and is already based on these findings could build a small wing span with sufficient lifting power. The first did the Wright brothers.

Lifting capacity aircraft photo 2

Avia.pro

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