> can anyone tell me how an ionizing air cleaner operates and how to build
> one...
It's basically a strong electrostatic field that the air flows through. Any
particles in the air become electrically charged, clump together, and then
either stick to the plates by electrostatic attraction or get caught by a
mechanical filter.
The ones I worked with (many years ago in a bar) were rectangular, designed
to replace a short section of the return air duct in a forced air system.
They had thin aluminum plates, several inches in width, running the length
of the filter and spaced about 2" apart. The plates were twisted at the
ends, and riveted to a frame, also of sheet aluminum. In the center of each
space between plates was a single bare wire, insulated at both ends and with
a bus bar at one end. The wire was charged to something like 15kv, negative
I think. Had wire mesh filters at both the entrance and exit; one to keep
the 'rocks' out of the filter and the other to catch any charged particles
that didn't stick to the plates. The outer housing stayed attached to the
ducts, but the power supply, the mesh filters, and the electrostatic filter
elements all came out the side. These were in a very dirty/smoky
environment, ISTR we had to soak the filters in Cascade about once a month
to remove the buildup of crud. The appearance of the "bath water"
afterwards would sure make you want to quit smoking ! We would know they
needed cleaning, because the "bug zapper" sound would increase to nearly
constant.
I haven't looked at one, but I'd guess the 'Ionic Breeze' thing being hawked
on TV has a half-cylinder ground element, with a charged wire in the center.
Air molecules near the wire get a negative charge, which then repels the
charge of the wire, and throws the molecules into the room, thus it doesn't
need a blower to achieve a very modest level of air circulation.
Several years back the "negative ion generators" were popular, these were
basically just a negatively charged tuft of stranded wire. The nearby walls
and floors served as the ground elements, and over time got plated with the
crud out of the air.
Randall
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/shop-talk
|