The weather is too hot to think of "fly to the sky" to teach the sun?Provide you with three methods

"Want to fly to the sky, side by side with the sun ..."

Feitian has always been a dream hidden in human heart. Because of this dream, we have paper kite, hydrogen balloon, and ... modern aircraft.

Looking at the literature related to aerospace, you will find that there are only three ways to fly to the sky!

01 becomes lighter than air

Under the standard conditions, the average relative molecular mass of the air is 29. As long as it can be found smaller than the air molecular weight, it can float in the air. Balls, ghost ball balls, etc.

The first hydrogen balloon in China was made by Hua Fang, an expert in the late Qing Dynasty. The method of making hydrogen balloons in the manufacture of hydrogen balls is actually very simple today. Essence

△ "Wushuo Playing Balloon" Hua Yanfang's balloon voyage scenery

The hot air balloon we are familiar with uses thermal gas instead of the lighter hydrogen or staple gas than the air. Because the density of the gas is inversely proportional to the absolute temperature, it can reduce the density and quality of the gas by increasing the temperature to achieve the lighter than the air. the goal of. The ancient Kong Ming lanterns are the earliest hot air balloons.

Either hydrogen balloon or hot air balloon. Although both are very good, it is difficult to control their flight direction. In order to better control the flying posture and direction, people are also designed and manufactured based on the "lighter" ideological method. airship.

The airship charges the lighter gases (generally used with a better safety of the air) in the interior to provide lift, and then install the engine on the airship to provide power to the airship level and control the flight attitude.

02 Manufacturing air pressure difference to lift off

When the object is flying in the air, the upper surface air flow rate is greater than the lower surface, forming a difference in air pressure, and it is also a way to achieve flight.

When there is a difference in air pressure differences in the upper and lower surfaces, the object can get a lift. If this lift is enough to overcome the gravity of the earth, the object can leave the ground!

Birds use air pressure differences to fly. Birds have natural flying body conditions: clever use of air dynamic wings, skeleton structure composed of hard and light hollow bones, developed pectoral muscles, unique respiratory systems, and light and smooth feathers.

The main reason for birds to fly is that they have mastered the flying knowledge of "making air pressure differences". When the birds are gliding in the air, the air forms a strong difference in the wings and lower parts, generating a upward lift, so that the birds can be held in the air without falling down 6.

In addition, the birds use active fluttering to generate a certain amount of pneumatic lift. When the wings of the birds are fluttering, it is equivalent to the propeller or jet promotion device of the aircraft, so that the birds can maintain a continuous flight state.

In fact, in the early days, the wooden birds and Da Vinci's fluttering planes made by Luban tried to imitate the flight status of birds to achieve the purpose of lift, but their flight plans ended in failure. Cognition of dynamic principles, blindly imitating the geometric shape and fluttering form of bird wings.

However, when people began to understand air dynamics and develop a fixed -wing aircraft like a kite, the modern transportation of the successful flying -aircraft was born. The same principle of aircraft and kites is the same as the speed of the air flow on the upper and lower surfaces of the wing, and the air pressure difference is made to obtain the lift.

All in all, whether it is birds, kites, propellers, jets, or helicopters, they all fly through the method of "manufacturing pressure differences", but they are different in the form of rising conditions.

03 Jets down the substance to get flying power

If the goal of our flying sky is to rush out of the earth, then the first two methods may not be very applicable, because space is a heavy environment, and there is basically no air and the pressure difference can be created. Therefore, it is necessary to use other forces to achieve flight.

For the Rockets, because the rocket not only carries fuel, but also carries oxidants, the engine can work without air.

In addition, the fuel and oxidant burned in the engine burning room to generate a large amount of high -pressure gases. High -pressure gases were sprayed out of high speed from the engine in nozzle, and the rocket obtained a reaction force that was opposite to the opposite of the gas, so that the Rockets took off and fly.

In fact, as early as the 17th century, Newton described it clearly as early as the 17th century. ","

In modern aerospaces, in order to achieve higher target flights, designers do not just use a certain use of these three "flying sky" methods to build aircrafts, but to integrate them. For example, in order to obtain a faster flight speed, the supersonic fighter aircraft uses a stamping engine that can be sprayed backward.

Although, the way humans have already mastered the three types of flying more than "becoming lighter than air", "manufacturing air pressure difference", and "spraying down to obtain flying power", but in the not far future, there will be more more than a future. Many people find more practical ways to fly to the sky!

The sky is like the dome, and the cage covers the four wilds. There should be a large piece in our activity territory. There are too many unknown things in the sky. When we work hard to eliminate these unknown, human civilization will have greatly developed!

[Editor in charge: Zhang Yongsu]

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