Build Electrodynamic Trap:Camera,Voltage,Distance

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To build an electrodynamic trap for aerosol particles using two ring electrodes, a voltage of 5 kV is recommended. The distance between the rings should be at least 1.6 mm to avoid air breakdown, with a larger spacing of about 1 cm suggested for safety. The electric field strength is critical, as it increases significantly at sharp edges, which can lead to unwanted sparks. For visualization of the particles, a suitable camera must be selected, but specific recommendations were not provided. This technology is utilized in devices like Honeywell's electrostatic air purifiers.
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I am new to physics. I am trying to build an electrodynamic trap using 2 ring electrodes to trap aerosol particles. I will be applying a voltage of 5 KV. What are the things that i need for example what camera do i use to visulaize the particles and what distance should i maintain between the rings
 
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Air breaks down at a field of about 30 kV/cm, modified a bit by humidity and significantly by the presence of larger particles. Since you don't want sparks, you want a spacing large compared to 5/30 cm or about 1.6 mm if you have smooth electrodes. The field increases dramatically at sharp edges, and more so at sharp points (the reason Franklin used sharpened rods to protect houses against lightning), so you might want to start with a cm or so.

This technology is common--take a look at Honeywell's electrostatic air purifier for home furnaces, or these links.

http://www.airpurifiers.com/technology/electronic.htm"
http://en.wikipedia.org/wiki/Electrostatic_air_cleaner"
 
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