CN112303010B

CN112303010B - High-efficiency low-noise centrifugal fan

Info

Publication number: CN112303010B
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: 2024-06-18
Anticipated expiration: 2040-11-03
Also published as: CN112303010A

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 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; the blades are designed in the shape of the M in the front edge area, so that the influence of horseshoe vortex and low-speed vortex during the working of the centrifugal fan can be well resolved, and the working 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 lower noise.

Background

When the centrifugal fan is operated, a complicated flow is liable to occur. When the fluid flows over the surface of the blade, the fluid is blocked by the blade, the flow speed is reduced, a reverse pressure gradient with high downstream pressure and low upstream pressure is generated, and when the reverse pressure gradient is high to a certain extent, the original movement of the fluid is stopped and moves in the upstream (reverse direction) under the action of the reverse pressure gradient, so that horseshoe vortex is formed on the surface of the blade. The occurrence of horseshoe vortex can improve the pneumatic noise of the fan and simultaneously reduce the working capacity of the fan. In addition, due to the characteristic that the fluid moves in the backward centrifugal blade path, low-speed vortex often occurs 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 affected.

Disclosure of Invention

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

The technical scheme adopted for solving the technical problems is as follows: the centrifugal fan with high efficiency and low noise 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 lines M1 and M2, a concave end a2 is formed between the inclined straight line M2 and M3, and a convex tip a3 is formed between the arc lines M3 and M4.

According to the centrifugal fan provided by the invention, the blades are designed in the shape of the M in the front edge area, 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 preferred embodiments of the present invention, the lengths of the arc line m1, the oblique straight line m2, the arc line m3 and the oblique straight line m4 are satisfied, where m1 > m3 and m2 > m4.

As some preferred embodiments of the present invention, the upper end of the trailing edge region is bent towards the center of the fan wheel disc to form a trailing edge bending part, and the 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 has an M-shaped structure.

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

The beneficial effects of the invention are as follows: the novel structure aims at the problem that horseshoe vortex and low-speed vortex are easy to generate when the centrifugal fan rotates, and by improving the blade structure, the horseshoe vortex and the low-speed vortex around the blade can be effectively reduced, the pneumatic noise of the centrifugal fan is reduced, and the working efficiency of the centrifugal fan is improved.

Drawings

The invention will be further described with reference to the drawings and examples.

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

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

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

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

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

Reference numerals:

Annular shroud 100, fan disk 200, blade 300, leading edge region 310, trailing edge region 320, trailing edge curve 321.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. In the following description, certain specific details are set forth in order to provide a thorough understanding of the application. While the application may be practiced without these specific details, it is possible that those skilled in the art will be able to more effectively introduce their operational nature to other persons of skill in the art using the descriptions and statements herein. Furthermore, it should be noted that, as used in the following description, the terms "front", "rear", "left", "right", "upper", "lower", etc. refer to directions in the drawings, and the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively, and the relative technical personnel do not need to make any inventive adjustments in the above directions simply and without understanding the technology beyond the scope of the present application. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the present disclosure. While well known techniques of manufacturing methods, control procedures, component sizes, material compositions, piping arrangements, etc. have not been described in detail in order to avoid obscuring the objects of the present application.

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

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

When the centrifugal fan works, the M-shaped structure of the front edge area 310 can rectify air flow when the air flow enters the centrifugal fan, so that the 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, examples of which are illustrated in the accompanying drawings, wherein the reference to "an embodiment" refers to 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 fixed to any particular order, nor should it be construed as limiting the application.

In example 1, referring to fig. 5, the lengths of arc line m1, inclined straight line m2, arc line m3, inclined straight line m4 satisfy the values, m1 > m3, m2 > 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 wheel 200 (e.g., right side as shown in fig. 3) to form a trailing edge bending portion 321, and the lower side of the trailing edge region 320 is recessed to form a C-shaped structure (e.g., front side recess as shown in fig. 5), so that the influence of low-speed vortex can be well resolved.

Embodiment 3, the meridional section of the blade 300 is an M-shaped structure, wherein the meridional section refers to: the blades are sectioned by any rotation shaft of the centrifugal fan, and the blades sectioned by the sections can be seen as M-shaped. The design scheme of the three-dimensional variable-section streamline blade can simultaneously reduce/relieve the horseshoe vortex of airflow along the axial speed distribution of the blade and the horseshoe vortex along the radial speed distribution of the blade, thereby achieving the effects of reducing the aerodynamic noise of the backward centrifugal fan and improving the functional force of the backward centrifugal fan.

In embodiment 4, the upper end of the blade 300 is a shroud-position blade profile line n1, the lower end of the blade 300 is a wheel disc-position blade profile line n2, and the lengths of the shroud-position blade profile line n1 and the wheel disc-position blade profile line n2 are satisfied, wherein n1 is greater than n2. The transverse extending directions of the blade profile line n1 at the wheel cover and the blade profile line n2 at the wheel disc are staggered to form an X-shaped structure, which is equivalent to the X-shaped structure in the top view of the blade 300, namely, the blade 300 is seen from the annular wheel cover 100 to the direction of the fan wheel disc 200, and the blade profile line n1 at the wheel cover and the blade profile line n2 at the wheel disc form a structure similar to the X shape. The design can effectively reduce low-speed vortex generated by the airflow at the tail edge of the blade, and the design effect according to the parameters of the invention is better.

The present invention is also capable of suitable alterations and modifications in the above-described embodiments, in light of the above principles. Therefore, the invention is not limited to the specific embodiments disclosed and described above, but some modifications and changes of the invention should be also included in the scope of the claims of the invention.

Claims

1. The utility model provides a centrifugal fan of high-efficient low noise, includes annular shroud (100) of upside and downside fan rim plate (200), annular shroud (100) with be provided with blade (300) between fan rim plate (200), its characterized in that:

The blade (300) comprises a leading edge region (310) and a trailing edge region (320), the leading edge region (310) is of an M-shaped structure, the leading edge region (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;

the lengths of the arc line m1, the inclined straight line m2, the arc line m3 and the inclined straight line m4 are satisfied, and m1 is more than m3 and m2 is more than m4;

The upper end of the tail edge region (320) is bent towards the center direction of the fan wheel disc (200) to form a tail edge bent part (321), and the lower side of the tail edge region (320) is recessed to form a C-shaped structure;

The meridian section of the blade (300) is of an M-shaped structure.

2. A high efficiency low noise centrifugal fan according to claim 1, wherein: the upper end of the blade (300) is provided with a wheel cover position blade profile line n1, the lower end of the blade (300) is provided with a wheel disc position blade profile line n2, the length value of the wheel cover position blade profile line n1 and the wheel disc position blade profile line n2 is met, n1 is more than n2, and the wheel cover position blade profile line n1 and the wheel disc position blade profile line n2 are staggered in the transverse extending direction to form an X-shaped structure.