Airplane sound problem, what is airplane noise?

It is the sound of the aircraft engine, the engine uses the third law of Newton's reaction force, after the engine starts, the compressor rotates to suck in the outside air, after the outside air enters the guide, the compressor presses the gas backwards one by one, the gas pressure is getting bigger and bigger, when the gas passes through the last stage, the gas pressure increases many times, and then enters the combustion chamber, in the combustion chamber, the electric injection fire, the oil injection burns, because the gas contains oxygen, the gas burns and expands, and is sprayed backwards, and the combustion chamber is behind the turbine, The turbine shaft is equipped with a turbine disc, the turbine disc is surrounded by blades, and then the turbine is rotated and then pressed backward one stage by one stage, and the gas is compressed through the turbine stage at the rear of the engine, and the pressure is increased by hundreds of times, and finally, it is sprayed out through the tail nozzle. A reaction force is created that causes the plane to fly forward. What you hear is the loud sound produced by the process.

When the engine is running at high speeds, the air produces a turbulent sound. Because the general passenger aircraft are twin-engine, when the speed of the two engines is not exactly the same, there will be sound interference.

The airplane flies at high speed and compresses the surrounding air. Make noise. I think that's where the rumble comes from.

Jet engines have that sound.

Generally, the sound of turbojet engines is heavy, and the sound of turbofan engines is high-pitched.

Engines, you think airplanes are wound up?

It depends on the atmospheric conditions at that time, the same plane, the same altitude and speed, if you fly at different times, some sounds may not be heard because of the reflection and refraction of the atmosphere on the sound waves, but sometimes the sound waves of the aircraft may not have any refraction, directly to your ears, the sound will be very loud. Of course, it's about airplanes, supersonic planes.

I'm afraid it's hard to see the imitation macro, otherwise it can shock people, Hushan airliner, 747 and EMB are two levels of noise at all.

The propagation speed of sound is related to the type and temperature of the medium, and the higher the temperature under the same strip of grinding parts, the farther the sound propagation;

Answer] The sound of different aircraft is different, some are sharper, some are lower, and the timbre of the sound produced by the aircraft is different from that of the airplane.

The atmosphere in the sky is dense, and the higher you go, the less dense it becomes; In the process of sound propagation, the gas must first vibrate, the mechanical energy is converted into the internal energy of the scattered beam, and the mechanical energy decreases, therefore, the sound will also produce a change in tone due to the change of gas density;

Therefore, the answer is: the timbre of the sound produced by the airplane when it flies is different; The atmospheric impulse in the sky is dense, and the higher the altitude, the smaller the density, and the timbre will also change the tone due to the change of gas density in the process of sound propagation.

This question examines the factors influencing the propagation and pitch of sound; It is important to note that the timbre of the sound produced by the aircraft when flying is determined by the characteristics of the emitter.

When an airplane takes off, it needs to accelerate from a standstill with all its might, so the engines of the airplane will run at maximum power, and naturally it will make a loud sound.

When the aircraft lands, it is a deceleration movement, and the engine does not need to output power, and the engine only runs at idle speed. So the sound of the launch is very small.

The sound of the aircraft mainly comes from the engine, the rest is wind noise, and the take-off and landing wind noise is very small.

When the plane takes off, the engine needs to increase the horsepower to take off, so it makes a lot of noise. Landing is the process of the aircraft slowing down to the runway and taxiing, and of course the sound will be relatively quiet.

The high-speed operation of the propeller of the aircraft during take-off produces a lot of noise, and the noise is low when it lands.

Generally speaking, the noise influence range is elliptical with the airport as the center, the maximum diameter is about 9 to 13 kilometers parallel to the airport runway, and the minimum diameter is about 5 kilometers.

However, it also depends on the throughput of the airport as if it is circling, after taking off, it needs to climb to the first flight altitude in the airspace demarcated by the airport, and then fly to the destination, and climb to the specified altitude of the flight.

Factors influencing aircraft noise.

Airport noise is the convergence of aircraft noise, it is related to the type of aircraft and the number of take-off and landing, its influence range is the vast area covered under the influence of a certain height of flight, so the size of the noise pollution area, and the location of the airport, the distance from the city, the take-off and landing mode and time arrangement of the aircraft, and the layout of the runway in the airport.

Since the 50s of the 20th century, the rapid development of air transport, the high speed of aircraft and the increase of payload, making the noise of aircraft more and more loud. Supersonic aircraft can also cause a roar. When the aircraft is flying at low altitude, the flight coverage of several kilometers wide can be formed within the influence of the n-shaped wave wavefront of the roar.

Aircraft noise pollution is becoming more and more serious, second only to ground traffic noise pollution in developed countries.

The noise of the aircraft is mainly generated by the engine, and the supersonic aircraft also have shock waves.

2.The piston engine of an airplane is generally more powerful than that of a car, and there is no special silencing equipment so it is noisy.

3.The acceleration of the gas turbine engine to the air is particularly large, so it is very noisy.

4.Airplanes are turbine engines, which forcibly compress the air and spray it out, the air vibrates, and the friction of gas molecules is of course noisy, which is the same as firecrackers.

5.When the plane starts, just like when the car starts, the engine is very loud when it starts, and when it starts, the engine is stationary and becomes motion, and the work done at this time is the largest, so the noise generated is also very large.

6.Let us see the anatomy of the human ear. In appearance, the ears are very inconspicuous, in fact, what we see is only a part of the ear, called the pinna, and there is a small hole in the auricle**, which is the external auditory canal.

7.The external auditory canal and pinna make up the outer ear, and its main function is to gather sound and transmit it to the eardrum. The tympanic membrane is the starting point of the middle ear, which also includes the tympanic chamber, ossicles, small muscles of the middle ear, and the pharyngeal tube.

The sound vibrations that gather in the outer ear are transmitted by the eardrum through the ossicles to the inner ear, which has a snail-like structure called the cochlea.

8.The cochlea has abundant sensory cells, which can translate the sound vibration into signals that the auditory nerve fibers understand, and finally receive it by the auditory center of the cerebral cortex, so that people can hear sounds.

Air resistance, high-speed flight of the aircraft, compressed air, friction makes a lot of noise. Engine noise. The engine rotor is the main component, and the speed is up to 6000-10000 rpm.

Jet noise. The high-velocity gas ejected from the engine is the driving force for the flight of the aircraft, and the speed is great.

The engine uses Newton's third law of reaction force, after the engine starts, the compressor rotates to suck in the outside air, after the outside air enters the director, the compressor presses the gas backwards one by one, the gas pressure is getting bigger and bigger, when the gas passes through the last stage, the gas pressure increases many times, and then enters the combustion chamber.

In the combustion chamber, the gas contains oxygen, the gas burns and expands, and is sprayed backwards, behind the combustion chamber is a turbine, and the turbine shaft is equipped with a turbine disk, and the turbine disc is filled with blades around the turbine disk, which is rotated by the turbine and then pressed backward one by one.

The gas is compressed through a turbine at the rear of the engine, the pressure is increased by a factor of several hundred and finally, and finally, it is ejected through the tail nozzle. A reaction force is created that causes the plane to fly forward. What you hear is the loud sound produced by the process.

The noise of civil aircraft is mainly the sound of high-velocity gases and air crashing from the engine.

After the engine starts, the compressor rotates to draw in the outside air, and the outside air passes through the compressor chamber, which presses the gas backwards, causing the pressure to increase. Then enter the combustion chamber, at this time the oxygen and the sprayed oil are fully combined and the fire is ignited, the gas instantly expands hundreds of times, discharges to the nozzle, and drives the turbine to work, this process will make a loud sound.

When seeing a plane take off from a nearby airport, everyone is familiar with the hum of jet engines. If you live near an airport, this sound may affect your life. When the plane flew a few kilometers away, the sound still seemed very loud, and you can imagine how loud it must be in the vicinity of the plane.

While people can hear sounds like "white noise" in the cabin, this one, which is only a few meters away from the engine, doesn't sound too loud. You might say that the cabin is well isolated from the outside world, but can the sound insulation really be that good? Or is there some other scientific principle in it?

Well, it's as simple as you think, and there are many parties working together to achieve the soft sound in the cabin.

Because the engine is propelled by the wind, an airplane that is so big. n_n。。。

Mostly the sound of jet engines.

If the thrust is high, the sound must be loud.

It is the sound of the aircraft engine, the engine uses the third law of Newton's reaction force, after the engine starts, the compressor rotates to suck in the outside air, after the outside air enters the guide, the compressor presses the gas backwards one by one, the gas pressure is getting bigger and bigger, when the gas passes through the last stage, the gas pressure increases many times, and then enters the combustion chamber, in the combustion chamber, the electric injection fire, the oil injection burns, because the gas contains oxygen, the gas burns and expands, and is sprayed backwards, and the combustion chamber is behind the turbine, The turbine shaft is equipped with a turbine disc, the turbine disc is surrounded by blades, and then the turbine is rotated and then pressed backward one stage by one stage, and the gas is compressed through the turbine stage at the rear of the engine, and the pressure is increased by hundreds of times, and finally, it is sprayed out through the tail nozzle. A reaction force is created that causes the plane to fly forward. What you hear is the loud sound produced by the process.