Plural odd number bell-like openings nozzle device for a fluidized bed jet mill

摘要

A jet mill includes plural nozzle devices for discharging a composite stream of high velocity fluid. Each nozzle device includes a plural odd number of nozzle openings for discharging an individual stream of high velocity fluid. Each nozzle opening comprises (i) a converging region for converging and accelerating a volume of high pressure fluid; (ii) a throat region defining a narrowest diameter region of the nozzle opening; (iii) a first expansion region for producing a linear expansion of the volume of high pressure fluid, and (iv) a second expansion region for producing a turning expansion as well as a parallel flow of the volume of high pressure fluid. The first expansion region has a radius "r 1 " and a length "s 1 " with radius r 1 and length s 1 determined such that (dr 1 /ds 1 ) is a constant. The second expansion region has a radius "r 2 " and a length "s 2 " with radius r 2 and length s 2 determined such that (dr 2 /ds 2 ) is non-linear and a function of s 2.