Fan blade with a wavelike varying installation angle

Abstract

This invention relates to a fan blade with a wave-like mounting angle, comprising a hub and a plurality of blades. The hub includes a central portion and an outer peripheral portion connecting the central portion. The hub has an axial direction, a horizontal direction perpendicular to the axial direction, and a radial direction. The blades are spaced in a ring around the outer peripheral portion. Each blade defines a blade root connecting to the end of the hub, a blade tip relative to the blade root, a blade leading edge located in the direction of rotation, and a blade trailing edge relative to the blade leading edge. Each blade includes a plurality of airfoil sections divided from the blade root towards the blade tip. Each airfoil section has a chord line extending from the blade leading edge to the blade trailing edge. The angle between the blade chord line and the horizontal direction is defined as the mounting angle. The blade root of each blade has an initial mounting angle connecting to the hub and a final mounting angle located at the blade tip. From the initial mounting angle to the final mounting angle, the angle or position of the mounting angle of the airfoil section exhibits a wave-like variation trend.

Claims

1. A fan blade with a wave-like mounting angle, comprising a hub and a plurality of blades, the hub comprising a central portion and an outer peripheral portion connected to the central portion, the hub having an axial direction, a horizontal direction perpendicular to the axial direction and a radial direction, the blades being spaced apart and arranged in a ring on the outer peripheral portion, each blade defining a blade root connected to the end of the hub, a blade tip relative to the blade root, a blade leading edge located on the front side in the direction of rotation, and a blade trailing edge relative to the blade leading edge, each blade comprising a plurality of airfoil sections divided from the blade root toward the blade tip, each airfoil section having a blade chord extending from the blade leading edge to the blade trailing edge, the angle between the blade chord and the horizontal direction being defined as the mounting angle, the blade root of each blade having a starting mounting angle connected to the hub and a ending mounting angle located at the blade tip, the angles or positions of the mounting angles of the airfoil sections sequentially exhibiting a wave-like variation trend from the starting mounting angle to the ending mounting angle.

2. The fan blade with a wave-like mounting angle as described in claim 1, wherein the line connecting the initial mounting angle and the final mounting angle is defined as a mounting straight line, and the mounting angles of the airfoil profiles are sequentially connected to form a wave-like mounting angle curve, which is divided into multiple wave segments by the mounting straight line.

3. The fan blade with a wave-like mounting angle as described in claim 2, wherein the wave bands are sequentially interspersed on both sides of the mounting line, each wave band having a torsional amplitude relative to the mounting line, and the torsional amplitudes of adjacent wave bands being positive and negative respectively.

4. A fan blade with a wave-like mounting angle as described in claim 1, wherein the initial mounting angle is greater than the final mounting angle.

5. The fan blade with a wave-like mounting angle as described in claim 1, further comprising a fan frame surrounding the outside of the blades, and the fan frame having a fan width.

6. The fan blade with a wave-like mounting angle as described in claim 5, wherein the airfoil profile has a maximum blade thickness greater than 3% of the fan width.

7. A fan blade with a wave-like mounting angle as described in claim 5, wherein the airfoil section of the blade tip has a blade tip thickness greater than 1.5% of the width of the fan.

8. A fan blade with a wave-like mounting angle as described in claim 1, wherein the wave-like trend of the airfoil profile is present near the blade tip.

9. A fan blade with a wave-like mounting angle as described in claim 8, wherein the mounting angles of the first four airfoil sections closest to the blade root change linearly, while the remaining mounting angles change in a wave-like pattern.

10. A fan blade with a wave-like mounting angle as described in claim 1, wherein the chord lengths of the airfoil profiles alternate from the blade root to the blade tip, thus presenting a wave-like chord length curve.

11. The fan blade with a wave-like mounting angle as described in claim 1, wherein the line connecting the initial mounting angle and the final mounting angle is defined as a mounting straight line, and the position of the mounting angles of the airfoil profiles is a wave-like variation along the mounting straight line.

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