Atomizer Design Challenge? (Bernoulli's Principle)

[Grayfox]

I understand why liquid is sucked into a tube of flowing air with a constricted end due to Bernoulli's principle, what puzzles me is why the air doesn't just take the path of least resistance instead of inducing liquid suction (see attached image). For example, if a 1/4 inch line at 30 psi has a 1 mm nozzle outlet, and a 2 mm line dunked in liquid somewhere along it, why doesn't the high pressure air just take the path of least resistance and bubble through the liquid? My guess would be the designers would have to make the diameter of the liquid line smaller than that of the nozzle to avoid this, but every cologne bottle I've looked at has a larger diameter liquid inlet tube than outlet nozzle. What am I missing here?

 

[Drakkith]

The air would have to displace the liquid, which would be more resistive than just going through the tube.

 

[Grayfox]

No not necessarily, especially in my example, the pressure head alone would have to be immense to overpower 30 psi, maybe something on the order of a 4 story building to accomplish that.

 

[carmatic]

i think that it is more likely that the liquid line is attached all the way at the nozzle...the way i think of it is like, there is a high pressure regime starting from the pump to the nozzle, and a low pressure , high velocity regime beyond the nozzle, and the liquid line is connected to this side of the nozzlethe other possibility i can think of is that there is a valve in the liquid line, forcing the air to exit via the nozzle, and when sufficient velocity and pressure drop has built up, the liquid will be sucked into the airstream and out of the nozzle

but I am not a physicist so i could be wrong on both counts

 

[Grayfox]

Those are some interesting design possibilities carmatic that are very plausible! Now I just would like know which one is the industry standard. I have since built the scenario I described and sure enough the high pressure air displaced the liquid, BUT, there was a configuration that temporarily induced suction from tinkering with the liquid and air valves! It was hard to maintain though and now I'm even more curious as to what the best nozzle-suction design is.