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Dielectrophoretic Standoff Assembly for Fenestral Electrostatic Precipitators
In the summer, dust and smoke from forest fires often comes in through the windows of my house. They have screens, but the
screens are only to keep insects out; the holes are much larger than the dust and smoke particles. Therefore, I would like the
screen to act as an electrostatic precipitator.
I'm pretty sure that idea isn't new, but how do you assemble said electrostatic
precipitator window screen?
Start with a frame, where each side of the frame is electrically conductive but isolated from the two sides with which it shares
corners. String wires across from one side to the other, such that the horizontal and vertical wires are in different planes. In
other words, the wires are attached to both the front and back of the frame, but on the front they're all horizontal (attached
to the left and right frame members) and on the back they're all vertical (attached to the top and bottom frame members).
Make the separation between the two planes small, like a millimeter or less. Now, if you connect high voltage to the two
planes (one positive and one negative) it will act as an electrostatic precipitator.
However, it will not be very durable, it could short out if something pushes on it, and an insect could squeeze through by
pushing the wires apart (when the HV is turned off, anyway). So we need something to hold the wires in place.
To accomplish that, put the screen as built so far into a vat, and fill the vat with a special liquid. The liquid consists of a
photopolymer resin (i.e. something that will become solid when exposed to ultraviolet light) and a solvent. The resin
molecules must be more electrically polarizable than the solvent molecules. Then apply a voltage to the screen, as before,
except it may be an AC voltage now. This will cause the resin molecules to assemble themselves between the two planes of
wires, where the wires cross over each other.
Then, very carefully, lift the screen out of the vat while maintaining the voltage (to hold the resin molecules in place), and
allow the excess resin and the solvent to drip off/evaporate. Then expose the screen to UV, and turn off the voltage. Now you
have a screen where the horizontal wires and the vertical wires are in different planes, but with a tiny plastic support
attached at each intersection. Now you can use this as an electrostatic precipitator in your window.
[notexactly, Feb 03 2018]
[notexactly, Feb 03 2018]
Not the same as electrophoresis (though they can be combined) [notexactly, Feb 03 2018]
||//In the summer, dust and smoke from forest fires often comes in
through the windows of my house.//
||Just one of many reasons why all the forests should be bulldozed and
built upon immediately.
||I just showed this to a friend, and he says surface tension
will coat the whole wires
when the screen is lifted out of the solution. That might
need some more work to get it to work perfectly. He (not
of a fan of 3D printing) also says that another method
be to use a 3D printer; first lay down one set of wires,
print a layer of dots of plastic where the intersections
be, and then put the second set of wires on. (I guess you
should print a layer of dots before the first set of wires
after the second set, too, as caps.)
||This is going to have to be more complicated as the dust build up has to be dealt with. The second wire layer might not be enough to act as a collection plate.
||A 'lifter' air current to buffer dusty air might be another way to go.
||I was thinking you'd remove it from the window and rinse it
once in a while.
||Whether person or mechtronics, the windows could be cleaned without view obfuscation.