Bionic current collector and fan

Abstract

The present invention belongs to the technical field of flow collectors and discloses a bionic flow collector and a fan. The flow collector comprises an annular protrusion, the back of which is an annular groove, the annular protrusion serving as the windward surface; and multiple bionic airfoils disposed within the annular groove. This application reduces backflow and operating noise at the impeller outlet, solving the technical problem of preventing air intake conditions from deteriorating under low-flow cross-impeller flow conditions and high-flow operating conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field related to current collectors, and more specifically, relates to a bionic current collector and a fan. Background Art

[0002] During the specific operation of the fan, the collector is responsible for rectifying the fan inlet, which is used to create a good air intake environment for fluid machinery such as the fan. Due to the complexity of the fan's operating conditions, when the fan is operating under low flow conditions or the design is unreasonable, the airflow at the impeller outlet will flow back to the collector or even flow out of the collector in the opposite direction, forming a cross-impeller flow phenomenon, which will seriously interfere with the fan's air intake environment. The fan's air volume and efficiency will be significantly reduced, and there will also be adverse effects such as increased noise. Therefore, how to design a reasonable collector shape is important for controlling the impeller outlet backflow, avoiding the cross-impeller flow phenomenon, reducing the impeller outlet backflow, and improving the efficiency of the fan and reducing noise.

[0003] Chinese Patent CN109595196B (Patent 1) discloses a design method for a bionic collector for a centrifugal fan impeller, which improves the impeller's air intake environment by forming a collector with bionic serrations. Chinese Patent CN106382259A (Patent 2) discloses a novel collector and a range hood using the collector, which proposes a mesh collector. Chinese Patent CN20684554U (Patent 3) discloses a collector and a centrifugal fan using the collector, which proposes a cross-cutting collector. All of the above patents are designed at the collector's air intake position. Under relatively good air intake conditions, these patents are unlikely to further improve the fan's air intake conditions. Therefore, under good air intake conditions, Patents 1 and 2 are unlikely to further improve the impeller's air intake conditions. However, under high air volume operating conditions, cross-impeller flow is not obvious. The mesh structure in Patent 2 and the cross-cutting structure in Patent 3 reduce the inlet area, increase the air intake resistance, and worsen the air intake conditions. In low flow operating conditions, Patents 1 and 2 cannot prevent cross-impeller flow. Summary of the Invention

[0004] In response to the above defects or improvement needs of the prior art, the present invention provides a bionic collector and a fan, which reduces the backflow and operating noise of the impeller outlet airflow, and solves the technical problem of the fan not deteriorating the air intake conditions under cross-impeller flow in small flow operating conditions and large flow operating conditions.

[0005] To achieve the above-mentioned purpose, according to one aspect of the present invention, a bionic collector is provided, which includes: an annular protrusion, the back of which is an annular groove, and the annular protrusion is the windward surface; and multiple bionic airfoils, which are arranged in the annular groove.

[0006] Preferably, the bionic airfoil includes an arcuate end and a tip, and the arcuate end is arranged at the center of the annular groove.

[0007] Preferably, the angle between the chord length of the bionic airfoil and the tangent of the annular groove is 16° to 24°.

[0008] Preferably, the chord length ranges from 5R to 7R, wherein R is the radius of the annular groove.

[0009] Preferably, the bionic airfoil is a hollow structure with a thickness of 0.5 to 1 mm.

[0010] Preferably, the bionic wing shape is a teal shape, a seagull shape and a long-eared owl shape.

[0011] Preferably, the span ratio of the bionic airfoil is 0.2 to 0.8.

[0012] Preferably, a plurality of the bionic airfoils are evenly distributed in the annular groove.

[0013] According to another aspect of the present invention, a fan using the above-mentioned bionic current collector is provided, characterized in that the bionic current collector is arranged at the air inlet of the fan.

[0014] In general, the above technical solutions conceived by the present invention, compared with the prior art, provide a bionic current collector and fan with the following beneficial effects:

[0015] 1. A bionic airfoil is set at the annular groove. Due to the streamlined structure of the bionic airfoil itself, the problem of improving the intake conditions and impeller outlet backflow under large working conditions is solved.

[0016] 2. The angle between the chord length of the bionic airfoil and the tangent of the annular groove is 16° to 24°. Since the bionic airfoil is tilted toward the air inlet, cross-impeller flow and backflow problems are effectively prevented under low flow conditions.

[0017] 3. The bionic airfoil has a cavity structure, which improves the backflow while effectively reducing the fan noise.

[0018] 4. The chord length of the bionic airfoil ranges from 5R to 7R, where R is the radius of the annular groove, which can ensure the fullness of the bionic airfoil in the annular groove, thereby ensuring backflow while avoiding cross-impeller flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a front view of the annular groove of the embodiment of the present application;

[0020] Figure 2 This is a cross-sectional view of the annular groove of an embodiment of the present application;

[0021] Figure 3 This is a schematic diagram of the arrangement of the bionic airfoil in the annular groove according to an embodiment of the present application;

[0022] Figure 4 This is a schematic structural diagram of the bionic airfoil of an embodiment of the present application;

[0023] Figure 5A This is a front view of a bionic current collector with a teal-shaped bionic wing installed in an embodiment of the present application;

[0024] Figure 5B This is an oblique view of a bionic current collector equipped with a teal-shaped bionic wing according to an embodiment of the present application;

[0025] Figure 6A This is a front view of a bionic current collector with a seagull-shaped bionic wing installed in an embodiment of the present application;

[0026] Figure 6B This is an oblique view of a bionic current collector equipped with a seagull-shaped bionic wing according to an embodiment of the present application;

[0027] Figure 7A This is a front view of a bionic current collector equipped with a long-eared owl-shaped bionic wing according to an embodiment of the present application;

[0028] Figure 7B This is an oblique view of a bionic current collector equipped with a long-eared owl-shaped bionic wing according to an embodiment of the present application;

[0029] Figure 8 Schematic diagrams of simulations of embodiments of the present application, wherein (a) is the simulation result of a common current collector, and (b) is the simulation result of the bionic current collector of the present application;

[0030] Figure 9 The simulation results of static pressure when the bionic current collector and the ordinary current collector are installed in the embodiment of the present application;

[0031] Figure 10 This is the simulation result of the total pressure efficiency of the bionic current collector and the ordinary current collector installed in the embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0033] See also Figure 1 and Figure 2 The present invention provides a bionic current collector, which includes an annular protrusion and a plurality of bionic airfoils.

[0034] The back of the annular protrusion corresponds to the annular groove, the annular protrusion is the windward surface, and a plurality of bionic airfoils are arranged in the annular groove.

[0035] The cross section of the raised portion of the annular protrusion is in the shape of an arc, and the radius is R.

[0036] The bionic airfoil includes an arc end and a tip, the arc end is the arc end of the head of the airfoil, and the tip is the pointed end of the tail. The arc end is set at the center of the annular groove, and the tip faces the center of the entire annular protrusion, such as Figure 3 As shown, the angle θ between the chord length of the bionic airfoil and the tangent of the annular groove is preferably 16° to 24°, and more preferably 21°.

[0037] In a further preferred solution, the chord length c of the bionic airfoil has a value range of 5R to 7R, wherein R is the groove radius of the annular groove.

[0038] In a further preferred embodiment, the bionic airfoil is a hollow structure with a thickness of 0.5 to 1 mm.

[0039] In a further preferred embodiment, a plurality of bionic airfoils are evenly distributed in the annular groove. In a further preferred embodiment, the number of the bionic airfoils is preferably 3 to 6.

[0040] The bionic wing is a teal type (such as Figure 4 、 Figure 5A and Figure 5B As shown), Seagull type (as shown Figure 4 、 Figure 6A and Figure 6B as shown) and long-eared owl type (as shown) Figure 4 、 Figure 7A and Figure 7B One of three airfoil types (shown).

[0041] The shape of the bionic airfoil is controlled by the following formula:

[0042] Z u =Z c +Z t

[0043] Z d =Z c -Z t

[0044] Among them, Z c is the mid-camber line of the airfoil, Z t is the thickness distribution of the airfoil, Z u is the upper surface line of the airfoil; Z d It is the lower surface profile of the airfoil.

[0045] Furthermore, the mid-arc Z c and thickness distribution Z t Mainly determined by the maximum arc Z c，max and maximum thickness Z t，max Decide:

[0046]

[0047]

[0048] in, is the dimensionless chord length, x is the x-coordinate of the airfoil, c is the chord length of the airfoil, S n and A n is the coefficient of the bionic airfoil, see Table 1 below for details.

[0049] coefficient Long-eared Owl Seagull Teal S1 3.9362 3.8735 3.9917 S2 -0.7705 -0.807 -0.3677 S3 0.8485 0.771 0.0239 A1 -29.4861 -15.246 1.7804 A2 66.4565 26.482 -13.6875 A3 -59.8060 -18.975 18.276 A4 19.0439 4.6232 -8.279

[0050] Table 1

[0051] Furthermore, the maximum arc Z c，max and maximum thickness Z t，max The relationship is:

[0052]

[0053]

[0054] Where χ is the airfoil aspect ratio, subscripts c and t represent the coefficients corresponding to the maximum camber and maximum thickness, respectively, and a c , b c , d c , a t , b t and d t The values ​​of are shown in Table 2 below:

[0055]

[0056]

[0057] Table 2

[0058] The airfoil span ratio χ ranges from 0.2 to 0.8, and is more preferably 0.4.

[0059] The flow field of the centrifugal fan under the highest efficiency condition under specific application is obtained through numerical simulation, and the flow from the impeller back to the collector is obtained. Figure 8 As shown in the figure, it can be clearly seen that the airflow returning from the impeller to the collector is much smaller at the groove of the teal bionic airfoil, which means that the bionic airfoil placed at the groove has a significant improvement effect on the return flow.

[0060] Through numerical simulation, the static pressure and efficiency comparison between the teal bionic airfoil of the present application and the general collector are obtained. Figure 9 and Figure 10 As shown. Figure 9 From the perspective of static pressure distribution, in the actual operating conditions of centrifugal fans (large air volume conditions, 10~19m 3 / min), the bionic airfoil collector is significantly higher than the general collector (prototype). Under the same static pressure, the air volume increase is between 2.5% and 5.3%. Figure 8 Improve the reflux effect, Figure 10 The efficiency of the centrifugal fan with a bionic airfoil is significantly higher than that of a conventional collector under high-flow conditions. Furthermore, noise measurements show that, at the same air volume, the A-weighted sound pressure level of the bionic airfoil is 0.3dB lower than that of a conventional collector under maximum air volume conditions. Therefore, from the perspectives of static pressure, efficiency, and noise, the collector with the bionic airfoil in the groove significantly outperforms the conventional collector.

[0061] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A bionic current collector, characterized in that: The current collector comprises: an annular protrusion, the back of the annular protrusion is an annular groove, and the annular protrusion is the windward surface; A plurality of bionic airfoils, wherein the plurality of bionic airfoils are arranged in the annular groove; The bionic airfoil is a cavity structure with a wall thickness of 0.5 to 1 mm; The bionic wing shape is a teal shape, a seagull shape or a long-eared owl shape.

2. The current collector according to claim 1, characterized in that The bionic airfoil includes an arc-shaped end and a tip, and the arc-shaped end is arranged at the center of the annular groove.

3. The current collector according to claim 1 or 2, characterized in that: The included angle between the chord length of the bionic airfoil and the tangent line of the annular groove is 16° to 24°.

4. The current collector according to claim 3, characterized in that The chord length ranges from 5R to 7R, where R is the radius of the annular groove.

5. The current collector according to claim 1, characterized in that The span ratio of the bionic airfoil is 0.2-0.

8.

6. The current collector according to claim 1, characterized in that A plurality of bionic airfoils are evenly distributed in the annular groove.

7. A fan using the bionic current collector according to any one of claims 1 to 6, characterized in that: The bionic current collector is arranged at the air inlet of the fan.

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