Efficient distributed flow guide structure of centrifugal fan

Abstract

The invention discloses a centrifugal fan efficient distributed flow guide structure, and belongs to the technical field of centrifugal fan structure improvement, the centrifugal fan efficient distributed flow guide structure comprises a centrifugal fan, an airflow deflection area in an air outlet of the centrifugal fan is provided with at least two deflection-preventing flow guide plates, and one side of each deflection-preventing flow guide plate makes contact with the upper cover side of the centrifugal fan; the other side of the anti-deflection guide plate is located between the upper cover side and the base side of the centrifugal fan, the anti-deflection guide plate comprises a front edge point part and a rear edge part, an upper surface part and a lower surface part are arranged between the front edge point part and the rear edge part, the upper surface part is of an arc structure, and the lower surface part is of a linear structure; the installation angles of the multiple deflection-preventing flow guide plates are gradually reduced in the air outlet direction or gradually reduced and then kept unchanged, and the front edge point portions of the deflection-preventing flow guide plates are located on the outer side of the high-speed area of the blade tip position. The air flow quality can be improved, the air volume is greatly increased, eddy current loss caused by air flow deflection is eliminated, and the fan efficiency is improved.

Description

Technical Field

[0001] The invention relates to a high-efficiency distributed flow guide structure for a centrifugal fan, belonging to the technical field of centrifugal fan structure improvement. Background Art

[0002] The structure of the centrifugal fan is as follows Figure 1 As shown, conventional centrifugal fans have different air inlet conditions on both sides, such as Figure 2 As shown in the figure, the side close to the upper cover is the main air inlet, and the side close to the base is the secondary air inlet. When the air flows in from the inlets on both sides and is thrown out after the fan blades do work, the velocity at the outlet plane close to the secondary air inlet is large, and the air flow can flow out from the outlet better, as shown in the figure. Figure 3 As shown, due to the existence of pressure gradient, the outlet plane velocity close to the main air inlet is small, which is manifested as the outlet air flow loss on the side where Y<0mm (close to the upper cover) becomes larger and larger. The airflow is first deflected and then sucked in by the fan blades to impact the tongue position, resulting in a decrease in air volume and a loss of work done by the fan blades. In addition, the airflow after being sucked in by the fan blades has a large impact on the tongue, resulting in an increase in noise. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a centrifugal fan with a high-efficiency distributed flow guide structure, which can improve the airflow quality, greatly increase the air volume, and eliminate the eddy current loss caused by airflow deflection, thereby improving the fan efficiency; further, a centrifugal fan with a high-efficiency distributed flow guide structure is provided, which can prevent the airflow from being sucked into the fan blades, reduce the impact of the airflow on the tongue mouth, and reduce noise.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A centrifugal fan high-efficiency distributed guide structure comprises a centrifugal fan, wherein at least two anti-deflection guide plates are arranged in the air flow deflection area in the air outlet of the centrifugal fan, one side of the anti-deflection guide plate is in contact with the upper cover side of the centrifugal fan, and the other side of the anti-deflection guide plate is located between the upper cover side and the base side of the centrifugal fan, the cross-section of the anti-deflection guide plate comprises a leading edge point portion and a trailing edge portion, an upper surface portion and a lower surface portion are arranged between the leading edge point portion and the trailing edge portion, the upper surface portion is an arc structure, and the lower surface portion is a straight line structure, the installation angles of a plurality of the anti-deflection guide plates gradually decrease along the air outlet direction or first gradually decrease and then remain unchanged, and the leading edge point portion of the anti-deflection guide plate is located outside the high-speed area of ​​the blade tip position.

[0006] The number of the anti-deflection guide plates is 2 to 6.

[0007] A noise reduction guide plate is arranged between the airflow deflection area and the tongue mouth in the air outlet of the centrifugal fan. The noise reduction guide plate has the same shape as the anti-deflection guide plate. One side of the noise reduction guide plate is in contact with the upper cover side of the centrifugal fan, and the other side of the noise reduction guide plate is located between the upper cover side and the base side of the centrifugal fan.

[0008] The number of the noise reduction guide plate is one.

[0009] There are three anti-deflection guide plates, and along the air outlet direction, the installation angles of the three anti-deflection guide plates are 72-78°, 42-48° and 32-38° respectively.

[0010] The installation angles of the noise reduction guide plates are 34-40 degrees respectively.

[0011] The material of the anti-deflection guide plate is PBT or LCP.

[0012] The material of the noise reduction guide plate is PBT or LCP.

[0013] Beneficial effects of the present invention: The present invention provides a high-efficiency distributed guide structure for a centrifugal fan, wherein the installation angles of a plurality of anti-deflection guide plates gradually decrease along the air outlet direction or first gradually decrease and then remain unchanged, and the added distributed guide plate structure has an installation angle that gradually decreases, and after passing through the leading edge diversion, one end of the lower surface of the anti-deflection guide plate cross section blocks the airflow from being deflected, and the other end of the upper surface leads out the tip airflow, accelerates to reduce the airflow deflection, and then passes through the lower surface of the next anti-deflection guide plate to block and then flow out to the outlet together, thereby improving the airflow quality, greatly increasing the air volume, eliminating the eddy current loss caused by the airflow deflection, and improving the fan efficiency.

[0014] In addition, a noise reduction guide plate is arranged between the air flow deflection area and the tongue mouth in the air outlet of the centrifugal fan. The noise reduction guide plate near the tongue mouth prevents the air flow from being sucked into the fan blades, reduces the impact of the air flow on the tongue mouth, and reduces noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of a conventional centrifugal fan;

[0016] Figure 2 for Figure 1 Schematic diagram of the main air inlet and the secondary air inlet;

[0017] Figure 3 This is a schematic diagram of the airflow movement of a standard centrifugal fan;

[0018] Figure 4 The design area division diagram of the centrifugal fan of the present invention;

[0019] Figure 5This is a structural diagram of a high-efficiency distributed flow guide structure of a centrifugal fan according to the present invention;

[0020] Figure 6 This is a structural diagram of a high-efficiency distributed flow guide structure of a centrifugal fan according to the present invention;

[0021] Figure 7 It is a structural schematic diagram of the anti-deflection guide plate in the present invention;

[0022] Figure 8 It is a schematic diagram of the overall structure of the efficient distributed flow guide structure of the centrifugal fan of the present invention;

[0023] The reference numerals in the figures are as follows: 1 - anti-deflection guide plate; 2 - noise reduction guide plate; 11 - leading edge point portion; 12 - upper surface portion; 13 - lower surface portion; 14 - trailing edge portion. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the protection scope of the present invention.

[0025] Example 1

[0026] like Figure 4 As shown in the figure, when the fan blade is from AC, the speed in the Z direction gradually decreases and the speed in the X direction gradually increases. Starting from point BC, the larger speed in the X direction causes the airflow to begin to be deflected, and the airflow cannot flow out to the outlet, reducing the air volume. When the fan blade is from CE, the speed in the Z direction gradually increases and the speed in the X direction gradually decreases. However, the speed in the X direction between CD is still significantly greater than the speed in the Z direction, which causes the deflected airflow to be sucked in by the fan blade again between CD, and then the impact on the tongue is enhanced, and it becomes gradually obvious as Y<0mm.

[0027] like Figure 8 As shown, the present invention discloses a high-efficiency distributed guide structure for a centrifugal fan, including a centrifugal fan, wherein the airflow deflection area in the air outlet of the centrifugal fan is provided with no less than two anti-deflection guide plates 1, and the number of the anti-deflection guide plates 1 is 2 to 6. If the performance of the fan is poor, the airflow deflection at the position of the poor performance is more obvious, and the number of the anti-deflection guide plates 1 needs to be increased accordingly, that is, the more serious the airflow deflection, the more anti-deflection guide plates 1 are required. One side of the anti-deflection guide plate 1 contacts the upper cover side of the centrifugal fan, and the other side of the anti-deflection guide plate 1 is located between the upper cover side and the base side of the centrifugal fan.

[0028] like Figure 7As shown, the anti-deflection guide plate 1 includes a leading edge point portion 11 and a trailing edge portion 14, and an upper surface portion 12 and a lower surface portion 13 are arranged between the leading edge point portion 11 and the trailing edge portion 14. The upper surface portion 12 is an arc structure, which can lead out the tip airflow and accelerate the airflow, and is more conducive to the airflow flowing out from the outlet; the lower surface portion 13 is a straight line structure, which has a blocking effect on the airflow and reduces the deflection of the airflow.

[0029] like Figure 5 As shown, the installation angles of several anti-deflection guide plates 1 gradually decrease along the air outlet direction or gradually decrease first and then remain unchanged. The leading edge point 11 of the anti-deflection guide plate 1 is located outside the high-speed area at the tip of the blade, around the edge of the fan blade, and the tail does not exceed the outside of the frame. A noise reduction guide plate 2 is arranged between the airflow deflection area and the tongue mouth in the air outlet of the centrifugal fan. The noise reduction guide plate 2 has the same shape as the anti-deflection guide plate 1. The designed anti-deflection guide plate and the noise reduction guide plate have uniform and identical cross-sections, which are easier to process industrially. The material is PBT or LCP, and the cost is low. In addition, the installation method of the noise reduction guide plate 2 is similar to that of the anti-deflection guide plate. One side of the noise reduction guide plate 2 is in contact with the upper cover side of the centrifugal fan, and the other side of the noise reduction guide plate 2 is located between the upper cover side and the base side of the centrifugal fan.

[0030] like Figure 5 As shown, in this embodiment, the number of the anti-deflection guide plates 1 is three, and the number of the noise reduction guide plate 2 is one. The leading edge point of the first anti-deflection guide plate 1 in the present invention is (X, Z) = (-13mm, -30mm), and the point is selected at the starting position where the airflow is deflected. The first guide plate structure is added here, and the installation angle of the first anti-deflection guide plate is 75°. After the blade tip airflow is diverted by the first leading edge, part of the airflow is blocked by the lower surface and flows out along the lower surface toward the outlet, and part of the airflow is accelerated to flow out toward the outlet through the upper surface, and the airflow direction behind the anti-deflection guide plate 1 is improved at the same time.

[0031] The leading edge points of the second anti-deflection guide plate 1 and the third anti-deflection guide plate 1 are evenly distributed between X = -13mm and X = 10mm in the X direction, specifically (X, Z) = (-3.6mm, -32mm), (X, Z) = (3.6mm, -32mm). In addition, the leading edge points of the second anti-deflection guide plate 2 and the third anti-deflection guide plate 3 in the Z direction cannot be lower than Z = -32mm, because when the leading edge point is lower than Z = -32mm, the leading edge point will directly contact the high-speed airflow at the blade tip, resulting in increased noise. Since the anti-deflection guide plate 1 improves the subsequent airflow direction, the installation angles of the second and third anti-deflection guide plates are gradually reduced and are 45° and 35° respectively. Since the airflow direction is gradually improved, the outlet air volume is greatly increased.

[0032] The present invention greatly increases the air volume by designing a structure of multiple anti-deflection guide plates, eliminates eddy current losses caused by air flow deflection, and increases fan efficiency.

[0033] In addition, the leading edge point (X, Z) of the noise reduction guide plate 2 in the present invention is (10mm, -30.5mm), which is selected at the position where the airflow is to be sucked into the fan blades, and the installation angle of the noise reduction guide plate 2 is 37°. The design purpose of the guide plate is to prevent the airflow from being sucked into the fan blades on the one hand, and on the other hand, the airflow flowing to the tongue mouth flows out toward the outlet under the acceleration of the upper surface, which greatly reduces the impact on the tongue mouth, reduces the pressure at the tongue mouth, and reduces the noise.

[0034] Example 2

[0035] like Figure 6 As shown, this embodiment is the same as the embodiment 1, except that it only includes three anti-deflection guide plates 1 but does not include the noise reduction guide plate 2.

[0036] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A centrifugal fan high-efficiency distributed flow guide structure, characterized in that: A centrifugal fan is provided, wherein an airflow deflection region in an air outlet of the centrifugal fan is provided with at least two deflection prevention guide plates (1), one side of the deflection prevention guide plate (1) is in contact with an upper cover side of the centrifugal fan, and the other side of the deflection prevention guide plate (1) is located between the upper cover side and a base side of the centrifugal fan, the deflection prevention guide plate (1) comprises a leading edge point portion (11) and a trailing edge portion (14), an upper surface portion (12) and a lower surface portion (13) are provided between the leading edge point portion (11) and the trailing edge portion (14), the upper surface portion (12) is an arc structure, and the lower surface portion (13) is a straight line structure, the installation angles of a plurality of the deflection prevention guide plates (1) gradually decrease along the air outlet direction or first gradually decrease and then remain unchanged, and the leading edge point portion (11) of the deflection prevention guide plate (1) is located outside a high-speed region at a blade tip position.

2. According to claim 1, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: The number of the anti-deflection guide plates (1) is 2 to 6.

3. According to claim 1, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: A noise reduction guide plate (2) is provided between the airflow deflection area and the tongue of the air outlet of the centrifugal fan. The noise reduction guide plate (2) has the same shape as the anti-deflection guide plate (1). One side of the noise reduction guide plate (2) is in contact with the upper cover side of the centrifugal fan, and the other side of the noise reduction guide plate (2) is located between the upper cover side and the base side of the centrifugal fan.

4. According to claim 3, a centrifugal fan high-efficiency distributed flow guide structure is characterized in that: The number of the noise reduction guide plate (2) is one.

5. According to claim 2, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: The number of the anti-deflection guide plates (1) is three, and along the air outlet direction, the installation angles of the three anti-deflection guide plates (1) are respectively 72-78°, 42-48° and 32-38°.

6. According to claim 4, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: The installation angles of the noise reduction guide plates (2) are respectively 34-40°.

7. According to claim 1, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: The material of the anti-deflection guide plate (1) is PBT or LCP.

8. According to claim 3, a centrifugal fan high-efficiency distributed flow guide structure is characterized by: The material of the noise reduction guide plate (2) is PBT or LCP.

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