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So I was browsing about natural resonant frequencies and how they work, and I stumbled upon this article:

https://www.euronews.com/2022/01/21/polish-town-tests-anti-smog-sound-cannon-to-tackle-pollution

I watched the video and tried to understand what was going on. Basically they are using a giant sound cannon to blast smog away.

I don't understand how this cannon is specifically targeting smog, and if not if that is even what it is supposed to do.

I am also working on a similar project and would like to know a few things.

  1. Does air have a natural frequency? (I am referring to just any cluster of air and not air as a total because I know that different air may have different natural frequencies) If so how might one find that natural frequency? If not, why not?

  2. How does that smog cannon from the link above work and what is its purpose?

  3. What other effects may different sounds(not just natural frequencies) have on gases and normal air? Could you change the temperature of air? Could you move specific particulates in air or just air as a whole? Could you change air pressure in specific areas on demand?

Thank you if you read my questions.

And I hope you answer and find this worth your time!

Edit: I now understand that the cannon was not specifically targeting smog and was instead destroying the temperature inversion layer to restore natural convection reducing air pollution. However my other questions still stand, and I still want to know if it is possible to target specific gases in the atmosphere with soundwaves/frequencies.

Edit: I just saw your answer Anna. However I do not understand what you mean by continuum of frequencies and if you did not understand what a natural resonance frequency is here: https://www.youtube.com/watch?v=BE827gwnnk4. The sound that he uses in that video the frequency of that sound's waves is the natural resonance frequency.

Also for my third question I am not addressing the cannon, but just in general it seems you have answered my question in terms of the cannon and have completely denoted the sub-questions within:

  1. Could you change the temperature of air?

  2. Could you move specific particulates in air or just air as a whole?

  3. Could you change air pressure in specific areas on demand?

Also for my first question: I also asked how you could measure these frequencies within air.

Thank you! Also sorry if I came off a bit aggressive or defensive. Also sorry if these edits are too long.

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If you read this link your questions can be answered .

Formation of the inversion layer causes a lack of vertical movement of the atmosphere and the occurrence of long-lasting high concentrations of pollution. The new invention makes use of shock waves, created by explosions of a mixture of flammable gases and air. These shock waves destroy the structure of the temperature inversion layer in the atmosphere and restore natural convection. Restoring vertical movements within the atmosphere causes a reduction in air pollution at the ground level. The system was tested at full technical scale in the environment. Preliminary effects indicate an average 24% reduction in PM10 concentration in the smog layer at ground level up to 20 m, with the device operating in 11-min series consisting of 66 explosions. It was also shown that the device is able to affect a larger area, at least 4 km2.

bold mine for emphasis

you ask:

  1. Does air have a natural frequency? (I am referring to just any cluster of air and not air as a total because I know that different air may have different natural frequencies) If so how might one find that natural frequency? If not, why not?

If you mean frequency in sound waves, the air as gas vibrates on a continuum of sound frequencies.

  1. How does that smog cannon from the link above work and what is its purpose?

As stated in the quoted abstract above, its purpose is to restore natural convection that the pollution layer of smog over the city does not allow to happen

  1. What other effects may different sounds(not just natural frequencies) have on gases and normal air? Could you change the temperature of air? Could you move specific particulates in air or just air as a whole? Could you change air pressure in specific areas on demand?

The change happens to air as a whole, when using this cannon. Using different sound frequencies may have a local effect. Not in the way you seem to envisage.

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  • $\begingroup$ I just noticed this comment button. Ok I am going to use this instead of excessive edits. $\endgroup$ Dec 1, 2022 at 6:30
  • $\begingroup$ What do you mean by continuum of frequencies. Also how do I measure these. Also if you need to learn more about natural resonance frequencies than here: youtube.com/watch?v=BE827gwnnk4 $\endgroup$ Dec 1, 2022 at 6:31
  • $\begingroup$ Also when you say using different sound frequencies may have a local effect. Could you describe these effects. Also please answer some of the sub-question I put under the first question in number 3. $\endgroup$ Dec 1, 2022 at 6:33
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    $\begingroup$ Sorry, but this is a site for answering questions in mainstream physics. This presupposes that a minimum of physics knowledge is necessary. It is not a site for giving courses in physics. I answered the question because I was interested to see what the physics behind it is, and I have stated it in my answer, with links, for anybody interested, but am not willing to watch arbitrary videos and discuss basic physics questions. $\endgroup$
    – anna v
    Dec 1, 2022 at 7:06
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For a continuous medium like air, there is no "resonance" or "resonant frequency". There is instead a characteristic impedance that is determined by its mass density and springiness. That impedance then determines how vibrations move through it and how those vibrations reflect off of objects contained within that medium.

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