Blade for centrifugal fan impeller, impeller and centrifugal fan

Abstract

The utility model relates to a blade for a centrifugal fan impeller, an impeller and a centrifugal fan, and the blade for the centrifugal fan impeller comprises a blade body with a pressure surface; the blade is characterized by further comprising a flow dividing piece which is restrained on the pressure face of the blade body, and a flow channel for airflow to flow is formed between the flow dividing piece and the pressure face of the blade body. The blade has the advantages that the flow dividing piece is arranged, and the flow channel for airflow to flow is formed between the flow dividing piece and the pressure surface of the blade body, so that when airflow enters the flow channel, due to the fact that the sectional area in the flow channel is small, the flowing speed of fluid can be increased, and the vortex generation probability can be reduced; and on the other hand, due to the forceful effect of the pressure surface of the blade body to the suction surface, the air flow which can change the direction originally can be separated by the flow dividing piece, so that vortexes on the suction surface on the blade body are not easy to generate, and meanwhile, the flow dividing piece can generate a rectification effect on the air flow, so that the generation of noise is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to centrifugal fan technical field especially, it is a kind of blade, impeller and centrifugal fan for centrifugal fan impeller blade. BACKGROUND

[0002] Centrifugal fan is widely used, and impeller is an important component of centrifugal fan. When centrifugal fan works, the flow separation in the impeller inlet passage is relatively large, the main reason is that the pressure of the pressure surface of the blade is high, the speed is low, the pressure of the suction surface is low, the speed is high, the pressure gradient makes the fluid receive a force pointing to the suction surface, and then causes vortex, so that centrifugal fan produces a lot of noise when working.

[0003] To solve the noise problem of centrifugal fan, a kind of centrifugal fan blade and the centrifugal fan with same are disclosed in Chinese utility model patent with patent No.ZL201921689988.1 (authorized announcement No.CN210889451U), the blade is provided with concave-convex wave type forward swept leading edge and sawtooth type backward swept trailing edge, so that vortex of side surface wall at leading edge and trailing edge of blade does not interfere with each other, thereby reducing the generation of pressure pulsation, and the phase angle of noise source in length direction of leading edge and trailing edge is staggered by forward swept section and backward swept section, so that local noise does not increase.

[0004] Although the above-mentioned blade can solve the noise problem of centrifugal fan, the above-mentioned blade has the following use limitations: the concave-convex wave type forward swept leading edge and the sawtooth type backward swept trailing edge can accelerate the flow velocity of boundary layer fluid at the leading edge of the blade, but the flow velocity of boundary layer fluid near the trailing edge is still low, and vortex cannot be avoided, causing flow loss; in addition, the method of opening small holes in the middle of the blade in the prior art has certain effect on noise reduction, but the pressure difference between the pressure surface and the suction surface is reduced, which can weaken the work function of the blade on the gas, and seriously affect the flow efficiency of the fan system. Therefore, the prior art needs to be further improved. UTILITY MODEL CONTENTS

[0005] The first technical problem to be solved by the utility model is to provide a blade for centrifugal fan impeller, which can reduce vortex generation, improve the flow efficiency of fan system and reduce noise.

[0006] The second technical problem to be solved by the utility model is to provide an impeller applied with the above-mentioned blade.

[0007] The third technical problem to be solved by the utility model is to provide a centrifugal fan applied with the above-mentioned impeller.

[0008] The utility model discloses a technical scheme for solving the first technical problem is as follows: a blade for centrifugal fan impeller, including,

[0009] The blade body has a pressure surface.

[0010] It is characterized in that it further comprises:

[0011] The shunt member is constrained on the pressure surface of the blade body, and a flow channel for airflow flowing is formed between the shunt member and the pressure surface of the blade body.

[0012] Preferably, the shunt member is a shunt piece, which extends along the length direction of the blade body, and is connected with the pressure surface of the blade body through at least two connecting blocks arranged at intervals.

[0013] Preferably, the cross section of the blade body and the cross section of the shunt piece are both circular arcs, the corresponding circle radius of the blade body is R1, the corresponding circle radius of the shunt piece is R2, R2=R1-δ, and δ is the distance between the shunt piece and the blade body.

[0014] Preferably, the value range of δ is R1 / 10≤δ≤R1 / 5.

[0015] Preferably, the chord length of the shunt piece is m, the chord length of the blade body is n, and the value range of m is n / 6≤m≤n / 4.

[0016] Since the installation position of the shunt piece has a great influence on the flow rate, speed and outlet angle of the fluid flowing through the flow channel, preferably, the blade body and the shunt piece share the same center O, two sides of the blade body (1) extending in the length direction are respectively denoted as point A and point D, point A and the center O form a straight line AO, point D and the center O form a straight line DO, the included angle formed by the straight line AO and the straight line DO is ∠AOD, the side of the shunt piece close to point A is denoted as point B, point B and the center O form a straight line BO, the included angle formed by the straight line AO and the straight line BO is ∠AOB, and the value range of ∠AOB is 1 / 3*∠AOD≤∠AOB≤1 / 2*∠AOD.

[0017] The utility model discloses a technical scheme for solving the second technical problem is as follows: a kind of impeller, with blade, it is characterized in that: the blade is above-mentioned blade, still including relatively interval arrangement front disc, rear disc and the middle disc between the front disc and rear disc, the blade has multiple, the both ends of each the blade are respectively installed on the front disc and rear disc, the middle disc is provided with the aperture for the blade to pass through.

[0018] The technical solution adopted by this utility model to solve the third technical problem mentioned above is: a centrifugal fan, including an impeller, characterized in that the impeller is as described above.

[0019] Compared with the prior art, the advantages of this utility model are as follows: By setting a flow divider, a flow channel for airflow is formed between the flow divider and the pressure surface of the blade body. When the airflow enters the flow channel, the fluid flow velocity will increase due to the small cross-sectional area of ​​the flow channel, thus reducing the probability of vortex generation. On the other hand, since the pressure surface of the blade body has a force on the suction surface, the airflow that would originally change direction will be separated by the flow divider. Therefore, vortices on the suction surface of the blade body are not easy to be generated. At the same time, the flow divider will rectify the airflow, thereby reducing noise generation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the impeller structure in an embodiment of the present invention;

[0021] Figure 2 for Figure 1 Schematic diagram of the middle blade structure;

[0022] Figure 3 for Figure 1 Another structural diagram of the middle blade. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] The centrifugal fan in this embodiment includes an impeller, such as... Figure 1 As shown, the impeller includes blades a, a front disk b and a rear disk c arranged at relative intervals, and a middle disk d located between the front disk b and the rear disk c. There are multiple blades a, and the two ends of each blade a are respectively mounted on the front disk b and the rear disk c. An opening (not shown in the figure) is provided on the middle disk d for the blades to pass through.

[0025] The above-mentioned blades have the same structure. The following explanation uses one of the blades as an example. Figure 2 and Figure 3 As shown, the blade in this embodiment includes a blade body 1. The blade body 1 has a pressure surface 11 and a suction surface 12 disposed opposite to the pressure surface 11. In this embodiment, the pressure surface 11 of the blade refers to the side facing the incoming flow to generate pressure, that is, the working surface, and the suction surface 12 of the blade refers to the side facing away from the incoming flow, that is, the non-working surface.

[0026] like Figure 2As shown in the figure, the blade further comprises a flow splitter 2 constrained on the pressure surface 11 of the blade body 1, and a flow channel 21 for airflow flowing is formed between the flow splitter 2 and the pressure surface 11 of the blade body 1. The flow splitter 2 in the embodiment is a flow splitter plate, which extends along the length direction of the blade body 1 and is connected with the pressure surface 11 of the blade body 1 through at least two connecting blocks 3 arranged at intervals.

[0027] The cross section of the blade body 1 and the cross section of the flow splitter plate are both circular arcs, the corresponding radius of the blade body 1 is R1, the corresponding radius of the flow splitter plate is R2, R2 = R1-δ, δ is the distance between the flow splitter plate and the blade body 1, and the value range of δ is R1 / 10≤δ≤R1 / 5.

[0028] As shown in the figure, Figure 3 The blade body 1 and the flow splitter plate share the same center O, two sides of the blade body 1 extending in the length direction are respectively denoted as point A and point D, point A and the center O form a straight line AO, point D and the center O form a straight line DO, and the included angle formed by the straight line AO and the straight line DO is ∠AOD; the side of the flow splitter plate close to point A is denoted as point B, point B and the center O form a straight line BO, and the included angle formed by the straight line AO and the straight line BO is ∠AOB, and the value range of ∠AOB is: 1 / 3*∠AOD≤∠AOB≤1 / 2*∠AOD.

[0029] The chord length of the flow splitter plate is m, and the chord length of the blade body 1 is n, and the value range of m is: n / 6≤m≤n / 4; as shown in the figure, Figure 3 The side of the flow splitter plate close to point D is denoted as point C, and the chord length of the flow splitter plate in the embodiment corresponds to the length of the straight line BC; and the chord length of the blade body 1 corresponds to the length of the straight line AD.

[0030] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A blade for a centrifugal fan impeller, comprising: a blade body (1) having a pressure surface (11); characterized in that it further comprises: a splitter (2) constrained on the pressure surface (11) of the blade body (1), the splitter (2) and the pressure surface (11) of the blade body (1) forming a flow channel (21) for airflow. The splitter (2) is a splitter plate extending along the length direction of the blade body (1), and the splitter plate is connected to the pressure surface (11) of the blade body (1) by at least two connecting blocks (3) arranged at intervals. The cross section of the blade body (1) and the cross section of the splitter plate are both circular arcs, the corresponding radius of the blade body (1) is R1, the corresponding radius of the splitter plate is R2, R2 = R1 - δ, and δ is the distance between the splitter plate and the blade body (1). The value of δ is in the range of R1 / 10≤δ≤R1 / 5.

2. The blade of claim 1, wherein: The chord length of the splitter plate is m, and the chord length of the blade body (1) is n, the value of m is in the range of n / 6≤m≤n / 4.

3. The blade of claim 2, wherein: The blade body (1) and the splitter plate share the same center O, the two sides of the blade body (1) extending in the length direction are respectively denoted as point A and point D, point A and center O form a straight line AO, point D and center O form a straight line DO, the included angle formed by straight line AO and straight line DO is ∠AOD; the side of the splitter plate close to point A is denoted as point B, point B and center O form a straight line BO, the included angle formed by straight line AO and straight line BO is ∠AOB, the value of ∠AOB is in the range of 1 / 3*∠AOD≤∠AOB≤1 / 2*∠AOD.

4. The blade of claim 3, wherein: The blade (a) is as claimed in any one of claims 1 to 6, further comprising a front disc (b), a rear disc (c) and a middle disc (d) arranged at intervals, the blade (a) has a plurality of blades (a), the two ends of each blade (a) are respectively mounted on the front disc (b) and the rear disc (c), and the middle disc (d) is provided with an opening for the blade to pass through.

5. The blade of claim 3, wherein: The impeller is as claimed in claim 7.

6. The blade of claim 3, wherein: ​ 7. An impeller having blades (a), characterized by: ​ 8. A centrifugal fan comprising an impeller, characterized by ​

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