Originally Posted by HookahWaffle
Ding ding, winner. Was just talking this over with a friend on aim actually.
You'd have to measure the air volume at any given time across each choke point, bowl, stem, diffuser, hose port, hose, hose tip, and add them cumulatively, and the density of the smoke factors in as well.
There are other factors that come into play other than average volume.
Just think for a second about if you had a 2 inch diameter hose that was a foot long...except the end had a cap on it with a hole poked in it with a diameter of 1 mm. The pull on this hose would be much harder than a hose with a 1 inch diameter and no cap even though the average volume of the larger hose would be greater.
There are a lot of factors at work here, gaseous molecule sizes, average kinetic energy of molecules, even taking into account things like airfoils (rounded port versus square port or slopingly smaller circumference or sudden decrease is circumference (like the cap with a hole)).
Basically there are a lot of variables that can't easily be accounted for.