Could we dispense with bulky isolation materials, and rely on plasma instead?
https://www.nature.com/articles/s41467-023-38522-5
https://www.nature.com/articles/s41467-023-38522-5
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Fascinating, most surely there could be further application of this knowledge to silencing things like welders and jet engines - the silent UFO?
In the house, well, what about ozone? Walls covered in glowing grids 😀
In the house, well, what about ozone? Walls covered in glowing grids 😀
The noise reduction relies on a Townsend discharge which can be sustained only over a limited range of electric field intensity and gas pressure.
In the paper, the distance between the electrodes (nichrome wire and and grounded mesh) in the "Metalayer" is 6 mm and the voltage between them is 8 kV.
This results in an electric field intensity (E= V/d) of (8,000/0.006) = 1.3 MV/m (megavolts per metre).
According to Paschen's law, at a constant pressure the voltage needed to cause an arc reduces as the gap size is reduced but only to a point. As the gap is reduced further, the voltage required to cause an arc begins to rise and again exceed its original value.
For air at standard temperature and pressure (STP), the voltage needed to arc a 1 metre gap is about 3.4 MV. This corresponds to an electric field intensity of 3.4 MV/m.
This leads me to consider placing electrodes inside (top and bottom) of a floorstanding loudspeaker in order to subdue internal resonances.
A different twist on the 'electrostatic' loudspeaker perhaps? 😊
In the paper, the distance between the electrodes (nichrome wire and and grounded mesh) in the "Metalayer" is 6 mm and the voltage between them is 8 kV.
This results in an electric field intensity (E= V/d) of (8,000/0.006) = 1.3 MV/m (megavolts per metre).
According to Paschen's law, at a constant pressure the voltage needed to cause an arc reduces as the gap size is reduced but only to a point. As the gap is reduced further, the voltage required to cause an arc begins to rise and again exceed its original value.
For air at standard temperature and pressure (STP), the voltage needed to arc a 1 metre gap is about 3.4 MV. This corresponds to an electric field intensity of 3.4 MV/m.
This leads me to consider placing electrodes inside (top and bottom) of a floorstanding loudspeaker in order to subdue internal resonances.
A different twist on the 'electrostatic' loudspeaker perhaps? 😊
And long term ozone exposure, harmful, look it up.
There will be a need to ground the enclosures, with fine mesh, to avoid that. That also will be an acoustic problem to solve.
What is the insulation material, what if your dog pees on the speaker?
Seriously, I have had to repair computers with rat pee, not a pleasant task.
I could not say eff off, friend had an ISO inspection next day, and computer blew.
Tiny rat got in through an open expansion slot.
Peed on fax modem card.
New motherboard, installed in a hurry.
Had to send it 30 km away.
After that, I stopped telling people I fix things.
I have better things to do.
There will be a need to ground the enclosures, with fine mesh, to avoid that. That also will be an acoustic problem to solve.
What is the insulation material, what if your dog pees on the speaker?
Seriously, I have had to repair computers with rat pee, not a pleasant task.
I could not say eff off, friend had an ISO inspection next day, and computer blew.
Tiny rat got in through an open expansion slot.
Peed on fax modem card.
New motherboard, installed in a hurry.
Had to send it 30 km away.
After that, I stopped telling people I fix things.
I have better things to do.
The field doesn't need to encompass the whole volume to be silenced. The 6mm thick grid array acts as a much more massive virtual wall. A thickness of lambda/1000 is sufficient.
This doesn't mean that the scheme is actually practical (ozone, etc), but it is an interesting development anyway