Ducted cooling system with radial-flow fan

A method of cooling a liquid-cooled engine of a vehicle comprising:

• providing a heat exchanger mounted in spaced relation with respect to the engine for cooling liquid by air, the air being directed from a front side of the heat exchanger through a rear side of the heat exchanger,
• providing duct structure comprising:
• an inlet portion coupled to the rear side of the heat exchanger so as to cover at least a portion of the rear side for receiving at least a portion of air exiting the rear side of the heat exchanger, said duct structure being sized to extend generally a width of the heat exchanger so that opposing ends of the duct structure are located generally at opposing sidewalls of the heat exchanger,
• a fan mounting portion disposed generally at a top portion of said duct structure and located at each end thereof so as to extend beyond a sidewall of the heat exchanger and generally adjacent to said sidewall said duct structure being constructed and arranged to receive air flowing into said inlet portion in an initial direction, and to change the direction of air flow to be generally transverse to said initial direction as said air moves generally upwardly and toward said fan mounting portion, said duct structure tapering outwardly toward said fan mounting portion such that said fan mounting portion has the widest cross-sectional area of the duct structure, and
• an exhaust passage communicating with each said fan mounting portion to exhaust air downwardly from said duct structure to an associated exhaust duct located at a respective sidewall of the heat exchanger,
• providing a centrifugal fan mounted in each of said fan mounting portion of duct structure such that air flowing through the heat exchanger and said duct structure is pulled by said fans, and
• employing at least one motor to drive said fans.

A cooling system for a vehicle having a liquid-cooled engine, the system comprising:

• a heat exchanger constructed and arranged to be mounted in spaced relation with respect to the engine for cooling liquid by air, the air being directed from a front side of the heat exchanger through a rear side of the heat exchanger,
• duct structure comprising:
• an inlet portion coupled to the rear side of the heat exchanger so as to cover at least a portion of the rear side for receiving at least a portion of air exiting the rear side of the heat exchanger, said duct structure being sized to extend generally a width of the heat exchanger so that opposing ends of the duct structure are located generally at opposing sidewalls of the heat exchanger,
• a fan mounting portion disposed generally at a top portion of said duct structure and located at each end thereof so as to extend beyond a sidewall of the heat exchanger and generally adjacent to said sidewall, said duct structure being constructed and arranged to receive air flowing into said inlet portion in an initial direction, and to change the direction of air flow to be generally transverse to said initial direction as said air moves generally upwardly and toward said fan mounting portion, said duct structure tapering outwardly toward said fan mounting portion such that said fan mounting portion has the widest cross-sectional area of the duct structure, and
• an exhaust passage communicating with each said fan mounting portion to exhaust air downwardly from said duct structure to an associated exhaust duct located at a respective sidewall of the heat exchanger,
• a centrifugal fan mounted in each of said fan mounting portion of duct structure such that air flowing through the heat exchanger and said duct structure is pulled by said fans,
• at least one motor operatively coupled to said fans to drive said fans;
• and
• wherein said duct structure has a plurality of bores therein and includes an air door structure associated with each said bore, said air door structures being constructed and arranged to remain closed, closing said bores until exposed to a predetermined threshold air velocity whereby said air door structures move to an opened condition, opening said bores.

Duct structure for a vehicle cooling system having a liquid-cooled engine and a heat exchanger mounted forward of said engine, said duct structure comprising:

• an inlet portion constructed and arranged to be coupled to a rear side of a heat exchanger so as to cover at least a portion of the rear side for receiving at least a portion of air exiting the rear side of the heat exchanger, said duct structure being sized to extend generally a width of the heat exchanger so that opposing ends of the duct structure may be located generally at opposing sidewalls of the heat exchanger,
• a fan mounting portion disposed generally at a top portion of said duct structure and located at at least one end thereof so as to extend beyond a sidewall of the heat exchanger and generally adjacent to said sidewall, said duct structure being constructed and arranged to receive air flowing into said inlet in an initial direction, and to change the direction of air flow to be generally transverse to said initial direction as said air moves generally upwardly and toward said fan mounting portion, said duct structure tapering outwardly toward said fan mounting portion such that said fan mounting portion has the widest cross-sectional area of the duct structure, and
• an exhaust passage communicating with said fan mounting portion to exhaust air downwardly from said duct structure to an exhaust duct located at the sidewall of the heat exchanger.