CN112303010A

CN112303010A - High-efficiency low-noise centrifugal fan

Info

Publication number: CN112303010A
Application number: CN202011208937.XA
Authority: CN
Inventors: 罗伟乐; 刘阳明; 王汉波; 叶涛; 覃万翔; 梁燕好
Original assignee: Guangdong Sunwill Precising Plastic Co Ltd
Current assignee: Guangdong Sunwill Precising Plastic Co Ltd
Priority date: 2020-11-03
Filing date: 2020-11-03
Publication date: 2021-02-02

Abstract

The invention discloses a high-efficiency low-noise centrifugal fan, which comprises an annular wheel cover at the upper side and a fan wheel disc at the lower side, wherein blades are arranged between the annular wheel cover and the fan wheel disc; the blade comprises a front edge area and a tail edge area, wherein the front edge area is of an M-shaped structure, the front edge area sequentially comprises an arc line M1, an inclined straight line M2, an arc line M3 and an inclined straight line M4 from top to bottom, a convex tip a1 is formed between the arc line M1 and the inclined straight line M2, a concave tip a2 is formed between the inclined straight line M2 and the arc line M3, and a convex tip a3 is formed between the arc line M3 and the inclined straight line M4; the M-shaped design of the front edge area is adopted by the blades, so that the influence of horseshoe vortex and low-speed vortex during the work of the centrifugal fan can be well eliminated, and the work efficiency of the centrifugal fan is improved.

Description

High-efficiency low-noise centrifugal fan

Technical Field

The invention relates to the technical field of centrifugal fans, in particular to a centrifugal fan with higher efficiency and low noise.

Background

When the centrifugal fan works, complex flow is easy to occur. When the fluid flows across the surface of the blade, the fluid is obstructed by the blade, the flow velocity is reduced, a counter pressure gradient with large downstream pressure and small upstream pressure is generated, and when the counter pressure gradient is large to a certain degree, the original movement of the fluid is stopped and moves upstream (in the opposite direction) under the action of the counter pressure gradient, so that a horseshoe vortex is formed on the surface of the blade. The presence of horseshoe vortices increases the aerodynamic noise of the fan and also reduces the work capacity of the fan. In addition, due to the characteristic of the fluid moving in the backward centrifugal blade path, low-speed vortex often appears at the back pressure surface of the tail edge of the blade at the outlet of the blade path, and the working efficiency of the centrifugal fan is also influenced.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a centrifugal fan with high efficiency and low noise.

The technical scheme adopted by the invention for solving the technical problems is as follows: the centrifugal fan comprises an annular wheel cover on the upper side and a fan wheel disc on the lower side, wherein blades are arranged between the annular wheel cover and the fan wheel disc; the blade comprises a front edge area and a tail edge area, wherein the front edge area is of an M-shaped structure, the front edge area sequentially comprises an arc line M1, an inclined straight line M2, an arc line M3 and an inclined straight line M4 from top to bottom, a convex tip a1 is formed between the arc line M1 and the inclined straight line M2, a concave end a2 is formed between the inclined straight line M2 and the arc line M3, and a convex tip a3 is formed between the arc line M3 and the inclined straight line M4.

According to the centrifugal fan provided by the invention, the M-shaped design of the front edge area is adopted by the blades, so that the influence of horseshoe vortex and low-speed vortex during the working of the centrifugal fan can be well eliminated, and the working efficiency of the centrifugal fan is improved.

As some preferable embodiments of the invention, the lengths of the arc line m1, the inclined straight line m2, the arc line m3 and the inclined straight line m4 are satisfied, m1 is more than m3, and m2 is more than m 4.

As some preferred embodiments of the present invention, an upper end of the trailing edge region is bent toward a center of the fan wheel to form a trailing edge bent portion, and a lower side of the trailing edge region is recessed to form a C-shaped structure.

As some preferred embodiments of the present invention, the meridional section of the blade is M-shaped.

As some preferred embodiments of the present invention, the upper end of the blade is a shroud-position blade profile line n1, the lower end of the blade is a disk-position blade profile line n2, the length of the shroud-position blade profile line n1 and the disk-position blade profile line n2 is satisfied, n1 is greater than n2, and the transverse extending directions of the shroud-position blade profile line n1 and the disk-position blade profile line n2 are staggered to form an X-shaped structure.

The invention has the beneficial effects that: the novel structure aims at the problem that horseshoe vortex and low-speed vortex are easily generated when the centrifugal fan rotates, and by means of improvement of the blade structure, the horseshoe vortex and the low-speed vortex around the blades can be effectively reduced, pneumatic noise of the centrifugal fan is reduced, and work efficiency of the centrifugal fan is improved.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a perspective view of the present invention;

FIG. 2 is a perspective view of a blade of the present invention;

FIG. 3 is a front view of a blade of the present invention;

FIG. 4 is a top view of a blade of the present invention;

fig. 5 is a left side view of the blade of the present invention.

Reference numerals:

annular shroud 100, fan disk 200, blades 300, leading edge region 310, trailing edge region 320, trailing edge bend 321.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. Rather, the inventive subject matter may be implemented without these specific details, i.e., those skilled in the art will be able to more effectively describe the nature of their work to others skilled in the art using the description and illustrations herein. Furthermore, it should be noted that the terms "front side", "rear side", "left side", "right side", "upper side", "lower side", and the like used in the following description refer to directions in the drawings, and the terms "inner" and "outer" refer to directions toward and away from the geometric center of a specific part, respectively, and those skilled in the art should not understand that the technology beyond the scope of the present application is simply and innovatively adjustable in the directions. It should be understood that the specific embodiments described herein are merely illustrative of the present application and do not limit the scope of the actual protection. Well-known manufacturing methods, control procedures, component dimensions, material compositions, pipe arrangements, etc., have not been described in detail since they are readily understood by those of ordinary skill in the art, in order to avoid obscuring the present invention.

Fig. 1 is a perspective view of an embodiment of the present invention, and referring to fig. 1, an embodiment of the present invention provides a high-efficiency, low-noise centrifugal fan including an upper ring shroud 100 and a lower fan disk 200, with blades 300 disposed between the ring shroud 100 and the fan disk 200. The blade 300 includes a leading edge region 310 and a trailing edge region 320, and when the centrifugal fan is rotating, wind flow generally flows from the leading edge region 310 into the blade channel and then from the trailing edge region 320.

Referring to fig. 2, 3, 4 and 5, the front edge region 310 has an M-shaped structure, and the front edge region 310 sequentially includes, from top to bottom, an arc line M1, an oblique line M2, an arc line M3 and an oblique line M4, a convex tip a1 is formed between the arc line M1 and the oblique line M2, a concave tip a2 is formed between the oblique line M2 and the arc line M3, and a convex tip a3 is formed between the arc line M3 and the oblique line M4.

When the centrifugal fan works, the M-shaped structure of the front edge area 310 can rectify airflow when the airflow enters the centrifugal fan, so that a vortex breaking effect is achieved, and the influence of horseshoe vortex and low-speed vortex on the efficiency of the centrifugal fan is solved.

Reference will now be made in detail to some embodiments, wherein "an embodiment" is referred to herein as a particular feature, structure, or characteristic that may be included in at least one implementation of the present application. The appearances of the phrase "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Furthermore, the details of one or more embodiments are not fixedly presented in any particular order, and are not intended to limit the invention.

In example 1, referring to fig. 5, the lengths of the arc line m1, the oblique straight line m2, the arc line m3 and the oblique straight line m4 satisfy that m1 is greater than m3, m2 is greater than m4, and the vortex breaking effect is better.

In embodiment 2, the upper end of the trailing edge region 320 is bent toward the center of the fan disk 200 (e.g., to the right as shown in fig. 3) to form a trailing edge bent portion 321, and the lower side of the trailing edge region 320 is recessed to form a C-shaped structure (e.g., to the front as shown in fig. 5), so that the influence of low-speed vortices can be well absorbed.

In embodiment 3, the blade 300 has an M-shaped cross section, wherein the cross section is: the blade is sectioned through any rotating shaft of the centrifugal fan, and the blade sectioned through the section can be seen as an M shape. The design scheme of the three-dimensional variable cross-section streamline blade can simultaneously reduce/relieve the horseshoe vortex distributed along the axial speed of the blade and the horseshoe vortex distributed along the radial speed of the blade, and achieves the effects of reducing the aerodynamic noise of the backward centrifugal fan and improving the work capacity of the backward centrifugal fan.

In embodiment 4, the upper end of the blade 300 is the blade profile line n1 at the wheel cover, the lower end of the blade 300 is the blade profile line n2 at the wheel disc, the length of the blade profile line n1 at the wheel cover and the blade profile line n2 at the wheel disc satisfy that n1 is more than n 2. The shroud blade profile line n1 and the disk blade profile line n2 are offset in the transverse direction to form an X-shaped structure, which corresponds to an X-shaped structure in a plan view of the blade 300, that is, the shroud blade profile line n1 and the disk blade profile line n2 form an X-shaped structure when the blade 300 is viewed from the annular shroud 100 toward the fan disk 200. The design can effectively reduce the low-speed vortex generated by the airflow at the tail edge of the blade, and the design effect is better according to the parameters of the invention.

The present invention can be modified and adapted appropriately from the above-described embodiments, according to the principles described above. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A centrifugal fan with high efficiency and low noise comprises an annular wheel cover (100) on the upper side and a fan wheel disc (200) on the lower side, wherein blades (300) are arranged between the annular wheel cover (100) and the fan wheel disc (200), and the centrifugal fan is characterized in that:

the blade (300) comprises a front edge area (310) and a tail edge area (320), wherein the front edge area (310) is of an M-shaped structure, the front edge area (310) sequentially comprises an arc line M1, an inclined straight line M2, an arc line M3 and an inclined straight line M4 from top to bottom, a convex tip a1 is formed between the arc line M1 and the inclined straight line M2, a concave end a2 is formed between the inclined straight line M2 and the arc line M3, and a convex tip a3 is formed between the arc line M3 and the inclined straight line M4.

2. A centrifugal fan of high efficiency and low noise according to claim 1, wherein: the lengths of the arc line m1, the inclined straight line m2, the arc line m3 and the inclined straight line m4 are satisfied, m1 is more than m3, and m2 is more than m 4.

3. A centrifugal fan of high efficiency and low noise according to claim 1, wherein: the upper end of the tail edge region (320) bends towards the direction of the circle center of the fan wheel disc (200) to form a tail edge bending part (321), and the lower side of the tail edge region (320) is sunken to form a C-shaped structure.

4. A centrifugal fan of high efficiency and low noise according to claim 1, wherein: the meridian section of the blade (300) is of an M-shaped structure.

5. A centrifugal fan of high efficiency and low noise according to claim 3, wherein: the upper end of the blade (300) is provided with a wheel cover blade profile line n1, the lower end of the blade (300) is provided with a wheel disc blade profile line n2, the wheel cover blade profile line n1 and the wheel disc blade profile line n2 meet the length value, n1 is more than n2, and the transverse extension directions of the wheel cover blade profile line n1 and the wheel disc blade profile line n2 are staggered to form an X-shaped structure.