Low-noise fan for information handling systems
In one or more embodiments, a fan assembly may comprise a fan hub with a plurality of blades, each blade having one or more cutouts through which laminar airflow from a front side of the blade can pass through the blade to a back side of the blade, reducing aeroacoustic noise. A cutout may be a lateral cutout, wherein the lateral cutout connects to an edge of a blade, or may be an internal cutout, wherein an internal cutout may be formed relative to a midline of the blade but does not connect to either edge of the blade.
1 . A low noise fan, comprising:
a fan housing;
a hub rotatably positioned in the fan housing; and
a plurality of blades coupled to the hub, each blade comprising:
a linear section positioned at a proximal end of the blade adjacent to the hub, the linear section corresponding to laminar air flow;
a curved section positioned at a distal end of the blade from the hub, the curved section corresponding to a turbulent air flow;
a transition section connecting the linear section to the curved section, the transition section corresponding to a transition of the laminar air flow to the turbulent air flow at the blade; and
one or more cutouts formed a radial distance from the hub and formed in the transition section such that each cutout is spaced-apart from the distal end of the blade,
wherein each cutout is formed with a cutout width that is substantially constant along the cutout, and
wherein each cutout is i) at a non-orthogonal angle with respect to a midline of the blade and ii) angled with respect to a surface of the blade.
2 . The low noise fan of claim 1 , wherein the one or more cutouts are formed between an edge of a blade of the plurality of blades and the midline of the blade.
3 . A cooling system for an information handling system, the cooling system comprising:
a motor;
a fan assembly comprising:
a fan housing;
a hub coupled to an output shaft of the motor and positioned in the fan housing; and
a plurality of blades coupled to the hub, each blade comprising:
a linear section positioned at a proximal end of the blade adjacent to the hub, the linear section corresponding to a laminar air flow;
a curved section positioned at a distal end of the blade from the hub, the curved section corresponding to a turbulent air flow;
a transition section connecting positioned between the linear section to the curved section, the transition section corresponding to a transition of the laminar air flow to the turbulent air flow at the blade; and
one or more cutouts formed a radial distance from the hub and formed in the transition section such that each cutout is spaced-apart from the distal end of the blade,
wherein each cutout is formed with a cutout width that is substantially constant along the cutout, and
wherein each cutout is i) at a non-orthogonal angle with respect to a midline of the blade and ii) angled with respect to a surface of the blade.
4 . The cooling system of claim 3 , wherein the one or more cutouts are formed between an edge of a blade of the plurality of blades and the midline of the blade.
5 . A blade for a low-noise fan, the blade comprising:
two surfaces, wherein a first surface of the two surfaces is a front surface based on a direction of rotation and a second surface of the two surfaces is a back surface based on the direction of rotation;
a linear section positioned at a proximal end of the blade adjacent to the hub, the linear section corresponding to a laminar air flow;
a curved section positioned at a distal end of the blade from the hub, the curved section corresponding to a turbulent air flow;
a transition section connecting between the linear section to the curved section, the transition section corresponding to a transition of the laminar air flow to the turbulent air flow at the blade; and
one or more cutouts formed a radial distance from the hub and formed in the transition section such that each cutout is spaced-apart from the distal end of the blade, wherein air flowing along the front surface in the linear section is generally laminar flow, air flowing along the front surface in the curved section is generally turbulent flow, and a portion of the air flowing along the front surface passes through the one or more cutouts to flow relative to the back surface,
wherein each of the cutouts is formed with a cutout width that is substantially constant along the cutout, and
wherein each of the cutouts is i) at a non-orthogonal angle with respect to a midline of the blade and ii) angled with respect to the two surfaces of the blade.
6 . The blade of claim 5 , wherein the one or more cutouts are formed between an edge of the blade.