Patent ID: 6343984
Filing Date: 2002-02-05
Classification: F04D,G06F

Abstract:
A cooling system which reduces aerodynamic and electromagnetic noise comprising:one or more cooling fans in a housing, each fan having a toroidal fan opening and disposed for providing positive airflow over a first planar region, along a first linear axis substantially parallel to the first planar region; an airflow grille, defining a second planar region substantially perpendicular to said first linear axis, said airflow grille defining a set of through-holes substantially parallel to said first linear axis wherein said grille opening is equal to or greater than said toroidal fan opening such that aerodynamic and electromagnetic noise are minimized; and a first laminar flow region disposed between said cooling fans and said airflow grille, said first laminar flow region defined by a laminar flow duct wherein said laminar flow duct has a geometry of a rectangular solid such that said laminar flow duct defines a Venturi opening, said Venturi opening being operative in conjunction with said one or more cooling fans to provide airflow through said Venturi opening from a region both upstream and above a region of said laminar flow duct containing said Venturi opening wherein airflow is parallel to said first laminar flow region, said laminar flow duct being coupled on a first end to a housing for said one or more cooling fans and on a second end to said airflow grille, and said laminar flow duct being substantially parallel to said first linear axis, wherein said laminar flow duct acts as an RF collimator to reduce electromagnetic noise.