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Discussion Starter · #1 ·
Yes, that's right. Underground fog dispersion system.

My daughter who works at a bowling alley got an industrial fogger. I mean this thing will fog a block in minutes.

Soil Auto part Vehicle

Question: I was thinking that I would bury PVC pipe in my yard with spouts that would break the surface in different locations. I'm thinking that 1. it would cool the fog and 2. that you could evenly distribute fog to different parts of your display.

I'm talking 20-30 feet of run with nozzles pointing up in about 4-6 different spots.

My other foggers wouldn't have the output to do this, but this thing can do it.

Thoughts????
 

Typical Ghoul Next Door
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Very nifty idea and great score... but something to consider: unless you cool the fog, you will end up with fog "spouts" instead of ground-hugging fog. Any way to send it through a chiller first before the ground piping?

(and welcome! :D )
 

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depending on the region your in, cooling might be moot as if you are burying the lines and the ground is cool enough the fog would pick up the cold from the tube walls. If not then like Frankie's girl says you would need to pre-chill.

As for if the fog machine itself can do it, it's dependent on how many cubic feet or cubic meters per minute this thing can push. I did some looking online and got some irregular results. The Jem Magnum 2000(not pro) can output 700 cubic meters of fog per minute. I couldn't find the output rate of the pro model but we'll assume its similar. Now the pro instructions I found online say it can operate for 3 second intervals with a 7 second cool time for a maximum of 6 bursts per minute. If the cubic foot ratio is the same for the regular to the pro unit than this device can deliver roughly 117 cubic meters of fog per burst(or every 10 seconds)

So presumably to assure the fog movement is smooth with minimum warming time in the tubes your tubing system shouldn't be more than 100 cubic meters internally. You'd have to calculate the volume of each tube to its end and add them to determine this.

also to consider the instructions say the output nozzle gets really hot and should be a meter from any people. Likely due to this the first meter of your tubing should be made from metal to assure it doesn't melt.
 

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Also generally speaking because all things operate the same as they follow the path of least resistance first, if you want all the tubes to disperse equally then each tube must both be the same length, and have the same amount of angles or turns in them from source to nozzle or you'll have nozzles that produce fog all the time and some that almost never produce.

this is of course unless the closer nozzles choke the output more than the further ones. forcing more of the fog to travel down the tubes instead of coming out the exits.
 

The Big Kahuna of Fright
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This is doable. We had a guy on the forum many years ago who did the exact same thing. He dug up trenches in his front yard and installed a network of lines to distribute fog. I recall showing this to my wife; she just shook her head. Labor intensive, messy, costly, but what an effect...
.
 

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just for record too 700 cubic meters is roughly a space 8.8 m x 8.8 m x 8.8 m. or 28.9 ft x 28.9 ft x 28.9 ft
 

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Discussion Starter · #8 ·
So the FDS (Fog Dispersion System. Not Feminine Deodorant Spray) is working quite well and better than I expected. I've used multiple fog machines on this since I had issues getting the timer to work on the heavy duty one and all created fog out of it. Even my smallest one spit substantial fog out.

I did have one drawback. The fog has condensed inside the piping and has created enough to clog one jet last night on a test run. It had been running for about an hour for 10 seconds every minute. It's been seriously cold lately and I don't think that helped it, but it works great and creates the desired effect of keeping the fog low here in MN. It's definitely worth the effort. Yard Lawn Water Grass Backyard
 

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So the FDS (Fog Dispersion System. Not Feminine Deodorant Spray) is working quite well and better than I expected. I've used multiple fog machines on this since I had issues getting the timer to work on the heavy duty one and all created fog out of it. Even my smallest one spit substantial fog out.

I did have one drawback. The fog has condensed inside the piping and has created enough to clog one jet last night on a test run. It had been running for about an hour for 10 seconds every minute. It's been seriously cold lately and I don't think that helped it, but it works great and creates the desired effect of keeping the fog low here in MN. It's definitely worth the effort. View attachment 518097
Any additional info you can provide? Size of tubing? Length of runs? Type of spout/outlet used?

Sent from my SM-T320 using Tapatalk
 

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There's no way you're not going to have some condensation in an underground pipe. If you pump hot fog into underground pipe, it will cool the fog and leave some residue in the pipe. Those of us with fog chillers see this residue as an oily glycol film on the inside of the chiller. If you pipe fog out of a chiller into the underground pipe, the pipe being warmer will cause the fog to warm and some will drip out in the form of liquid.

Most people use 3" diameter pipe to move fog around their haunts. If you're piping with anything less, you'll need to start with a larger diameter pipe (e.g, 3") and then branch to smaller diameter pipes that at least equal the volume that could come through the original pipe unless you want to greatly change the density and/or flow rate. e.g., if you start with a 3" pipe, you will need at least 10 1" diameter pipes, or 2 2" diameter pipes. (see below for the math). If you don't have enough output pipe, your density and flow will increase. Increasing density will cause the fog to heat up and start to change back to a liquid.

Warning: Math follows....
The formula for the surface of a circle is pi*radius squared, so the 3" pipe yields 7 sq inches, a 2" pipe yields 3 sq inches, and a 1" pipe yields 3/4 of a square inch. If you begin piping in a 3" pipe, you can put a Y fitting in and split it into 2 2" pipes with an increase in flow rate of 16%, which is likely not deadly. If you split it with a Y into a 2 2" pipes and then split one of the 2" pipes into 1" pipes, your split from 2" to 1" will go from 3 square inches of input to 1.5 square inches of output. That is a 100% increase in flow rate, which would likely cause significant condensation in the pipe. To prevent that, you'd want to split the 2" pipe into 4 1" pipes.
 

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The following is speculation. But, I disagree about the idea that starting with pre-chilled fog will help the condensation much. That is because I don't think the fog is condensing. The fog is already liquid, in tiny droplets, and some droplets stick to the walls of the pipe.

I've wondered if applying a water repellant would tend to help the situation. Something like rain-x. Though, when I tried rain-x on my car windows, it seemed to make the dew stay as tiny droplets, rather than tending to join other droplets of water, and spread out. So, fogged up windows were harder to see out of.
 

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I installed channel drains by the front porch and driveway. In the process I also made a port for a fog machine, at the time I thought why not. Tested it and the fog came out the drains as expected even at the furthest point. My piping is 1.5" and the runs are about 30'.
 
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