Micromachined virtual impactor

摘要

A separation plate (10) includes a first surface and an opposing second surface. Plural pairs of a nozzle (14) and a virtual impactor (16) are provided on the first surface. Each nozzle tapers from an inlet end (14a) to an outlet end (14b). Each virtual impactor comprises a pair of generally fin-shaped projections (24). Each fin-shaped projection includes an inner wall (26) and a convex outer wall (28). The inner walls of the fin-shaped projections of a virtual impactor face each other to define a minor flow passage (30) therebetween. The convex outer walls of the fin-shaped projections of a virtual impactor cooperatively present a convex surface including a virtual impact void therethrough. The virtual impact void defines an inlet end of the minor flow passage. A virtual impactor body (33) is provided between adjacent virtual impactors (16). When a particle-laden fluid stream (23) is caused to flow through the nozzles and advance to the virtual impactors, a major portion of the fluid containing a minor portion of particles flows around the virtual impactors, is blocked by the virtual impactor bodies, and redirected from the first surface through a suitable major flow outlet. A minor portion of the fluid containing a major portion of particles enters the virtual impact voids, advances through the minor flow passages, and exits therefrom, where it can be collected, analyzed, or processed further in any other manner.