Piping (gases and liquids)

[D_x]

Is conveyor-like model of transferring fluids and gases through pipes final?

It is somewhat unintuitive. Especially on junctions (where it is always split 50/50 even if one pipe have only one vent and other whole system of vents) and on more complex parts where inputs and outputs are mixed (it cannot decide where to move, moves back and forth, clogging part or whole system).

http://tinyurl.com/jydqj9w

Here is the mock-up of problematic ventilation system.

I am expected pips to move like on falstad.com.
But they do not. With only one air pump - first left turn takes 50% of air (25% per vent) and right side receives almost nothing. Second pump does not change distributon. Third pump makes whole ventelation system behave very strange.
Valves can help, but they behave like diodes (transfer only in one direction) and gas valve have too low max value. And why minimum valve cannot be zero or off?

Electrical equivalent circuit may be a good tool to model physical processes to the desired level of complexity (it can be pretty simple)