the Know of a behavior particle in a air channels with variable section is very importance, for the projection of aerodynamic classification equipment.An important factor it represents the cognition of ultimate position (floating position) which have it a solid particle in the air channel, obtaining thus the level whereat must put the collection box of this. Position of the collection box is can determine on experimental path but and on analytic path (as much for the existing equipment how much fittings and for one finder out in the stage of projection).
