Spiral Air Assist?

All the current air nozzle designs have the air assist enter radially, causing the air to basically make a 90 degree turn inside the nozzle and creating a very turbid flow. Would it be more efficient to have the air assist enter the nozzle axially, pointed down slightly, creating a downward spiral of air? Would this create a more defined stream of air that would help to keep the beam path to the material clear of smoke?