The present application discloses an impeller for a centrifugal fan and a centrifugal fan. The impeller comprises a support member and several vanes. The support member has an inner wall that defines a hollow portion. The several vanes are arranged inside the hollow portion, each of the several vanes is connected with the inner wall and extends along the axial direction of the support member, and the several vanes are arranged along the circumferential direction of the support member. Each of the several vanes is bent and comprises a front edge, a tail edge, a convex suction surface, and a concave pressure surface, the suction surface and the pressure surface are arranged to oppose each other, and the front edge and the tail edge are arranged to oppose each other, wherein the tail edge is connected with the inner wall of the support member, and wherein several protrusions are provided on the suction surface, and the several protrusions are arranged to be close to the front edge. The protrusions can regulate the flow of a fluid immediately when the fluid contacts the vanes. During the flow regulation process, a large vortex in the fluid can be divided into several small vortices. Such small vortices have smaller friction resistance, and the kinetic energy dissipated from the motion of the small vortices themselves can be partially cancelled out, thereby reducing the noise of the impeller and improving the performance of the centrifugal fan.

The invention relates to a profiled structure elongated in a direction in which the structure has a length exposed to an airflow and transversely to which the structure has a leading edge and/or a trailing edge, at least one of which is profiled and has, along said direction of elongation, geometric serration patterns defined by a succession of peaks and troughs. Along the profiled leading edge and/or trailing edge, the serration patterns have a geometric pattern that is repeated in the direction of elongation, the shape of which is stretched and/or contracted transversely to the direction of elongation and/or in the direction of elongation.

The present invention relates to a blower, the blower according to an embodiment of the present invention comprising: a lower case having a suction hole formed therein through which air is introduced; an upper case arranged on the upper side of the lower case and having a discharge hole formed therein through which air is discharged; and a fan arranged in the lower case and including a plurality of blades. Each of the plurality of blades includes a plurality of airfoils respectively extending along different camber lines from one another, and a leading edge of connecting the leading ends of the plurality of airfoils. Entrance angles formed by the respective camber lines of the plurality of airfoils and the rotation directions of the blades are different from one another. Thus, due to the curved shape of the leading edge and the design of a recessed notch, a flow separating from the leading edge is reduced, and thus, there is an advantage in that air volume performance is improved.

A fan frame body structure includes a first frame body. The first frame body has a first upper end, a first lower end, a first frame wall and a first main flow way. The first main flow way passes through the first frame body and is formed with a first main inlet and a first main outlet respectively at the first upper end and the first lower end. A first subsidiary flow way is disposed in the first frame wall. The first subsidiary flow way is in parallel the first main flow way. The first subsidiary outlet is positioned at the first upper end of the first frame body in flush with and in adjacency to the first main inlet.

There is provided a rotating machinery including: a rotating body R which is rotatable around an axis O and has a first facing surface P1 that widens in a plane intersecting the axis O; a stationary body S which faces the first facing surface P1 from the axial direction O, and has a second facing surface P2 forming a flow path F1 through which a fluid flows from a radially inner side toward the radially outer side between the first facing surface P1 and the second facing surface P2; and a rotation side projection portion 80 which projects from the first facing surface P1 toward the second facing surface P2, has an annular shape around the axis O, and faces the second facing surface P2 via a clearance C.

A ceiling fan may include a shaft coupled to a ceiling, a cover to surround the shaft, a main blade having a blade hole which is a space open inward, and a sub-blade positioned in the blade hole. The sub-blade is disposed to have an angle of attack different from an angle of attack of the main blade. The ceiling fan may resolve a red zone of the air flow and may improve air volume and the flow rate due to the dual blades.

The invention relates to a rotor blade (10) for a turbomachine, in particular of an aircraft, comprising an airfoil (12) comprising a pressure face (15) and a suction face (17) extending from a leading edge (14) to a trailing edge (16), the airfoil (12) comprising an axis of elongation extending substantially along the leading (14) and trailing (16) edges, the airfoil (12) comprising a radially firmer end for connection to a rotor and a free radially outer end. According to the invention, the airfoil (10) further comprises at least one series of fins (24) situated on said free end, each of these fins (24) comprising a pressure face (26) situated on the suction face (17) side of the airfoil (12), and a suction face (28) situated on the pressure face (15) side of the airfoil (12).

A free-tipped axial fan assembly features a shroud barrel comprising an inlet, the radius of said inlet at its upstream end being greater than the radius of said inlet at its downstream end. An angle, in a plane including the fan axis, between the surface of said inlet and the direction of the fan axis varies non-monotonically with respect to a surface coordinate which increases with distance along the surface of the inlet.

The present invention relates to a blower. A blower according to an embodiment of the present invention comprises: a lower case having a suction hole in through which air flow; an upper case which is disposed at the upper side of the lower case and which has a discharge port through which the air is discharged; a fan motor for providing rotating force; and a fan disposed inside the lower case and fixed to a motor shaft of the fan motor, wherein the fan includes: a hub having an outer surface, which is extended to be inclined at a first angle with respect to the motor shaft; a plurality of blades coupled to the hub; and a shroud having an inner surface which is extended to be inclined, with respect to the motor shaft, at a second angle that is greater than the first angle, and which faces the outer surface of the hub with respect to the blade, and thus the air discharged from the fan can change into an ascending current.

The present application discloses a blade, comprising a blade tip, a blade root, a leading edge, and a trailing edge, wherein the leading edge and the trailing edge each extend from the blade tip to the blade root; the blade may rotate around a rotation axis, and the rotation axis and a normal plane of the rotation axis perpendicularly intersect at the foot of the perpendicular; a projection of the leading edge on the normal plane along the rotation axis is a first curve, and the first curve has an even number of inflection points. The blade of the present application can reduce noise and improve aerodynamic performance when the blade rotates.