I have read on several fog machine websites that they recommend transferring the fog through a 3"-6" duct to keep the fog from recondensing into its liquid form again. I'm intending on pressurizing several hundred feet of 3/4" pipe with a glycol fog and have it coming out of several small outlets throughout the line.
If you are talking about glycol vapor being pumped through the pipes, the bigger pipe will have an advantage.
The bigger the pipe, the less vapor would condense prematurely in the pipes before coming out.
Sadly, but I don't really have a clue how you would figure out mathematically how big of a difference it would make.
Having a pipe with a four or more times lower radius will significantly influence the flow and condensation in the pipe.
Sadly, I cannot really tell whether it would still work. My guess is yes, but you would have quite a bit of condensation in the pipes which could be a problem.
They might leak glycol or clog the flow or something.One thing is for certain: you wouldn't get as much fog out one side as you put in the other.
The people who write the websites you read through will have some experience with this, so if you are going to do it right maybe take the bigger pipes(they probably know what they are talking about).
30 meters of pipe doesn't sound like a little garage project