I have used ultrasonic misters for almost three decades. Originally, the transducers were only available from TDK and very expensive. Now, they are a few dollars each and available as single submersible pucks or big arrays. Here is a fast and inexpensive way to
build a
ground fog unit using ultrasonic misters if you want to
build your own.
5 gallon bucket with lid from big box store
One each 12
transducer model DK12 mister
array.
http://www.mainlandmart.com/foggers.html Or similar.
Cut three holes in the lid. One to match a 4' diameter muffin style fan. Mount fan so flow is pointed in to pressurize the bucket
Second hole is for
fog exhaust. I use 3" vacuum hose and fittings from big box store.
Third hole is for low
voltage cable to
transducer assembly that sits on the bottom of the bucket.
I typically add a float valve in the bucket to auto fill with water. Set valve to stop water fill no more than about 1/2" above
transducer surface. Something like this
If water is too deep than that it will limit
fog output.
Use cool water. warm water will limit
ground flow
effect from hose.
I put the fan on a variable speed controller to control flow. You can also do this manually by putting a damper over the fan intake.
You can run the
fog over dry ice to improve
ground hugging quality.
This technique leaves a lot of water on the floor surface. Not really a good solution for continuous duty situations
These transducers require clean water. Soft water is best if available. Hard water will dramatically reduce
transducer life. Replacement
transducer discs are available.
Clean the water busker after each use. Ultrasonic transducers scrub dirt and bacteria from the air and will create a petri dish of goo in your bucket if you don't clean it.
DO NOT add scents or chemicals to the water. These transducers atomize at very small particles and you can set up a lung hazard if you add chemicals.
If you just want to buy a large volume
unit, go here
http://www.mainlandmart.com/humidify.html
Still makes a wet mess but really pumps the
fog
Good luck!