Atomisation of Liquid Using Air

I am not sure what your application is going to be, but water is atomized most of the time using pressurized water applied to a nozzle designed for this purpose. I use water atomization periodically when designing a fire suppression system that is "practically" dry when impinging on equipment.

Google "misting nozzle" and you will get some hits you may find interesting.

Yes, misting nozzles can produce 30-40 micron droplets.

"Yes, misting nozzles can produce 30-40 micron droplets."

Of a liquid with an undefined viscosity? This discussion might be about mayonnaise.

Hey! We might be able to use this technique on the LynDoor™ Supervelocity Arrest Nanomechanical Device With Individual Condiments-Handheld^® (SANDWICH^®)!

[edit] I was composing when kramarat posted. Didn't mean to step on ya.

No problem. These guys should know to go to Lyndoor first, regardless of what they don't need.

Touche'

But, I was using the LynDoor™ Carnac^® Random Answer Generator (RAG)

Not to be confused with LynDoor™ SWAGG.

I knew I'd get close.

Your guess was closer than mine.

I don't think we should put pesticides or fertilizers on our SANDWICH. I doubt that is an added value feature any potential sucker customer will be looking for.

I don't know of a formula, but I do know that when spraying paint, the viscosity of the liquid is at least as important as cfm and psi.

There are a lot of variables here that come into play. Do you have one specific liquid in mind?

The liquids are pesticides, fertilizers, etc - it is a agricultural sprayer - a mist blower. The liquids currently work fine passing through a single 0.8mm hole but that produces 80-90 micron droplets, but we would like to achieve 30-40 microns with 80-90% of droplets. Up to 60 microns with the remaining 10-20% would be acceptable.

I think that increasing pressure, switching to a smaller orifice, or both would do the trick. I guess the system is not like spray paint systems, where tips can be changed out for different materials and applications. You may want to look into paint spray tips and changing them out with what you're currently using, you can pretty much dial in the atomization with your needs, and easily change tips when needed.

Don't forget though, if you get the droplets too small, they may either evaporate or blow away before they reach their intended target.

These guys should have both the expertise and equipment you are looking for.

http://www.bete.com/

At any diesel injection book you could find what you look for, but further theory look for Julian Lacoste work or Crua proffesor work.-

viscostity and pressure plus orfice size would be the main factors .

Can the OP please clarify?:

What is the liquid, and how much flow?
What is the flow of the air stream into which the liquid will be sprayed?
Is there also compressed air that will be injected into the atomizer nozzle? What pressure and flow?

If I understand correctly, this sounds like air atomizing of boiler fuel, in which case Ferquiza's GA applies.

Not with this, I hope, "The liquids are pesticides, fertilizers, etc"

The liquids are a variety of agricultural chemicals - the specific gravity should be fairly close to 1. The flow rate would be between 200 and 300 ml/min depending on whether there could be more than one liquid outlet in the air stream.

The primary blower that the system is being designed for would be the Stihl SR 450 http://www.stihlusa.com/blowers/SR450.html. The tube is approximately 3" in diameter and it gives 920m³/h (542 cfm) at 90 m/sec (201mph) but with not a terrible lot of pressure. It has a dosage unit which is used to adjust the flow on the standard configuration. There is no separate air injected into the nozzle as far as we are aware.