Patent ID: 7731100

Claim:
A method of controlling flows of secondary, low pressure air and carrier-air-conveyed dry chemical within a cylindrical enclosure containing at least one linear VGA nozzle, said VGA nozzle emitting high velocity air and atomized spray through a common window formed in said cylindrical enclosure, the method comprising: delivering in separate channels, said flows of secondary, low pressure air and carrier-air-conveyed dry chemical within said cylindrical enclosure; dividing each of said flows into two streams to thereby exit said cylindrical enclosure on opposite sides of said VGA nozzle through said common window; further dividing each of the two divided streams of said secondary, low pressure air into two separate portions; directing one portion of each of said further divided streams of said secondary, low pressure air to flow toward the spray exiting from said VGA nozzle so that said portion is entrained into a plume of said exiting spray by an expansion of said high velocity air, thereby effecting a smooth and immediate dilution of the spray without adverse deposition of solids on a face of said VGA nozzle from eddy recirculation of droplets; and directing the other portion of each of said further divided streams of secondary, low pressure air to flow substantially parallel with the flow of said exiting spray and to intersect and thereby divert, from the immediate vicinity of said exiting spray as it exits the nozzle, the flow of said carrier-air-conveyed dry chemical and a flow of ambient gas sweeping around said cylindrical enclosure, as the flow of said carrier-air-conveyed dry chemical is being entrained into the expanding high velocity air.