Patent ID: 7261007

Claim:
A particle concentrating device for separating a primary aerosol flow into secondary and tertiary aerosol flows with different particulate concentrations, including: a housing having a perimeter wall; the housing including a housing structure defining a first fluid passage running lengthwise along the perimeter wall, open to an exterior of the housing, and extending inward from the housing wall to a first-passage exit to accommodate a primary flow of an aerosol in an inward first direction with respect to the housing, wherein the aerosol comprises a gaseous medium and particles suspended in the medium and the particles comprise first particles having aerodynamic diameters above a selected threshold and second particles having aerodynamic diameters below the selected threshold; the housing structure further defining a second fluid passage downstream of the first fluid passage, to accommodate fluid flow away from the first-passage exit in a second direction different from the first direction; the housing structure further defining a third fluid passage disposed inwardly of the first fluid passage, to accommodate fluid flow away from the first-passage exit in the first direction; a first fluid-drawing component in fluid communication with the second fluid passage, adapted to draw a first portion of the primary flow toward and into the second fluid passage and thereby deflect the gaseous medium and second particles of said first portion while the first particles of said first portion tend to continue moving in the first direction due to particle momentum, thus to provide a secondary flow of the aerosol through the second fluid passage; and a second fluid-drawing component in fluid communication with the third passage, adapted to draw a second portion of the primary flow inward toward and into the third fluid passage, thus to provide a tertiary flow of the aerosol through the third fluid passage, the tertiary flow comprising the gaseous medium and particles of said second portion merged with first particles of said first portion.