Centrifugal fan blade top micro-bulge structure
By adding tiny protrusions on the top of the centrifugal fan blades and changing the airflow flow method, the energy loss and noise problems caused by vortex formation in traditional designs are solved, and more efficient air volume output and lower noise are achieved.
Patent Information
- Application Number
- CN202421205545.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-30
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-05-30
AI Technical Summary
In traditional centrifugal fan design, the gap between the top of the blade and the upper cover causes airflow to deflect and accelerate, forming a large velocity gradient, which in turn induces the formation of vortex and increases energy loss and noise.
Add tiny bumps at the appropriate position on the top of the blade, altering the airflow flow, and reducing or eliminating vortex between the top of the blade and the upper cover.
By reducing or eliminating eddy current, reducing noise, increasing air volume, and improving the overall performance of the fan.
Smart Images
Figure CN222797757U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of air supply equipment, and in particular to a micro-protrusion structure on the blade top of a centrifugal fan. Background Art
[0002] In traditional centrifugal fan designs, the gap between the top of the blade and the upper cover is usually small. When the airflow passes through this area, it is deflected and accelerated due to space limitations, resulting in a large velocity gradient. The velocity gradient induces the formation of vortices, which not only increase energy loss, but also cause noise generation, affecting the overall performance of the fan.
[0003] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the application and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to ordinary technicians in the field. Utility Model Content
[0004] The purpose of the present invention is to provide a centrifugal fan blade top micro-protrusion structure, by adding a tiny protrusion at a suitable position of the blade top, by changing the way the airflow flows, reducing or eliminating the eddy current between the blade top and the upper cover, reducing the intensity and influence range of the eddy current, reducing noise, and thus increasing the air volume.
[0005] In order to achieve the above objectives, this application is implemented by adopting the following technical solutions:
[0006] A centrifugal fan blade tip micro-protrusion structure comprises a blade hub, a plurality of blades are fixedly connected to the outer side of the blade hub, and each of the blades is provided with a plurality of blade protrusions.
[0007] Optionally, the fan blade hub diameter is 23.8-30.2 mm.
[0008] Optionally, the outer diameter of the fan blade is 42-70 mm, and the thickness of a single blade is 0.2-0.8 mm.
[0009] Optionally, the fan blades rotate counterclockwise.
[0010] Optionally, the several blade protrusions include a first protrusion, a second protrusion and a third protrusion, each of the blade protrusions is composed of four arc curves, the second protrusion and the third protrusion have consistent size parameters, and the protrusion heights of the first protrusion, the second protrusion and the third protrusion are greater than 0.1 mm and less than 1 / 2 of the gap between the upper cover and the blade top.
[0011] Optionally, the four endpoints of the curve of the blade protrusion are the intersection points of circular references of different diameters and the curves of the leading and trailing edges of the blades. The circular reference is formed by the central arc curve of each blade protrusion offset by a preset distance toward the tip and root directions, respectively. The central arc curve is an arc curve formed within the blade protrusion with the center point of the blade hub as the center and the radius from the center point of the blade hub to the center point of the blade protrusion.
[0012] Optionally, the diameter of the central arc curve of the first protrusion is 0.8 to 0.9 times the outer diameter of the fan blade, the diameter of the central arc curve of the second protrusion is 0.9 to 0.95 times the outer diameter of the fan blade, and the diameter of the central arc curve of the third protrusion is 0.95 to 1 times the outer diameter of the fan blade.
[0013] Optionally, the first protrusion includes a first protrusion first curve, a first protrusion second curve, a first protrusion third curve and a first protrusion fourth curve, the first protrusion first curve, the first protrusion second curve, the first protrusion third curve and the first protrusion fourth curve are connected in sequence to form a quadrilateral, the width of the first protrusion is the same as the width of the blade, the first protrusion second curve and the first protrusion fourth curve are circular arc curves, and the first protrusion first curve and the first protrusion third curve are circular arc curves, straight lines or elliptical curves.
[0014] Optionally, the positions of the plurality of blade protrusions are arranged on an actual direction line of the flow field at the gap between the fan blade top and the upper cover.
[0015] Optionally, a silent ring is provided on the edge of the blade.
[0016] Compared with the prior art, the present invention has the following beneficial effects:
[0017] Tiny protrusions are added according to the actual direction of the flow field at the gap between the fan blade top and the upper cover to ensure that the blade protrusions can change the way the airflow flows in the direction of the airflow, reduce or eliminate the eddy current between the blade top and the upper cover, reduce the intensity and influence range of the eddy current, reduce noise, and thus increase the air volume. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of a centrifugal fan blade with a micro-convex structure on the blade top of the utility model;
[0020] Figure 2This is a front view of a centrifugal fan blade with a micro-convex structure on the blade top;
[0021] Figure 3 This is a partial enlarged view of the blade protrusion of a centrifugal fan blade top micro-protrusion structure of the utility model;
[0022] Figure 4 This is a schematic diagram of a first protrusion structure of a centrifugal fan blade top micro-protrusion structure of the utility model;
[0023] Figure 5 This is a schematic diagram of a second protrusion structure of a centrifugal fan blade top micro-protrusion structure of the utility model;
[0024] Figure 6 It is a schematic diagram of the vortex flow direction of the utility model without blade protrusions;
[0025] Figure 7 It is a schematic diagram of the eddy flow direction after the blades of the centrifugal fan blade top micro-convex structure are installed with the utility model.
[0026] Description of reference numerals:
[0027] 1. Fan wheel hub; 2. Blades; 3. Blade protrusions; 31. First protrusion; 311. First curve of first protrusion; 312. Second curve of first protrusion; 313. Third curve of first protrusion; 314. Fourth curve of first protrusion; 32. Second protrusion; 321. First curve of second protrusion; 322. Second curve of second protrusion; 323. Third curve of second protrusion; 324. Fourth curve of second protrusion; 33. Third protrusion; 4. Silent ring; 5. Intersection; 6. Center arc curve. DETAILED DESCRIPTION
[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use.
[0029] Embodiment 1:
[0030] The fan blade top micro-raised structure comprises a fan blade hub 1, a plurality of blades 2 are fixedly connected to the outer side of the fan blade hub 1, a plurality of blade protrusions 3 are arranged on each of the blades 2, and a silent ring 4 is arranged on the edge of the blade 2.
[0031] The fan hub 1 has a diameter of 28 mm, the fan blade outer diameter is 64 mm, and the thickness of a single blade 2 is 0.8 mm.
[0032] The design of the rounded edges helps to reduce airflow separation at the protrusions, guides the airflow more smoothly around the protrusions, avoids sudden flow changes, reduces the formation and intensity of vortices, reduces high-frequency noise caused by sharp edges, reduces the overall noise level of the fan, and improves air volume and fan performance.
[0033] The blade protrusion 3 includes a first protrusion 31, a second protrusion 32 and a third protrusion 33. Each blade protrusion 3 is composed of four arc curves. The size parameters of the second protrusion 32 and the third protrusion 33 are consistent. The protrusion heights of the first protrusion 31, the second protrusion 32 and the third protrusion 33 are 0.5 mm.
[0034] like Figure 3 As shown, the four end points of the curve of the blade protrusion 3 are the intersection points 5 of the circular references of different diameters and the front and rear edge curves of the blade 2. The circular reference is formed by the central arc curve of each protrusion offset by a preset distance of 0.1 mm toward the tip and the root of the blade. The diameter of the central arc curve of the first protrusion 31 is 57.5 mm, the diameter of the central arc curve of the second protrusion 32 is 60.5 mm, and the diameter of the central arc curve of the third protrusion 33 is 63 mm. The first protrusion 31 includes a first protrusion first curve 311, a first protrusion second curve 312, a first protrusion third curve 313 and a first protrusion fourth curve 314. The diameter of the first protrusion first curve 311 is 2.58 mm, the second protrusion 32 includes the second protrusion first curve 321, the second protrusion second curve 322, the second protrusion third curve 323 and the second protrusion fourth curve 324, the diameter of the second protrusion first curve 321 is 6.4 mm, the arc diameters of the first protrusion second curve 312 and the second protrusion second curve 322 are 11.4 mm, the distance between the arcs of the first protrusion third curve 313 and the second protrusion third curve 323 is 7.8 mm, and the arc diameters of the first protrusion fourth curve 314 and the second protrusion fourth curve 324 are 13 mm.
[0035] The main purpose of adding the blade protrusion 3 is to change the airflow pattern. When the airflow encounters the tiny blade protrusion 3, it will be guided to bypass the blade protrusion 3, thereby changing the originally straight flow path. The airflow is deflected and separated when encountering the blade protrusion 3, reducing the strong vortex formed in the gap between the blade top and the upper cover, and decomposing the large vortex into small vortices. The intensity and influence range of these small vortices are relatively small, which significantly reduces the energy loss and noise caused by the vortex.
[0036] like Figure 6 and Figure 7 As shown, the positions of several blade protrusions 3 are determined according to the actual direction of the flow field at the gap between the fan blade top and the upper cover. When the airflow hits the blade protrusion 3, the large vortex is decomposed into small vortices.
[0037] Embodiment 2:
[0038] Based on the first embodiment, an implementation of a blade 2 is provided.
[0039] A layer of silent ring 4 is arranged on the edge of the original blade 2, and the silent ring 4 is a silencer.
[0040] Different from the first embodiment, the provision of the silent ring 4 can reduce the noise through the blade protrusion 3 in the first embodiment, and at the same time absorb part of the noise through the silent ring 4, so that the sound energy transmitted through the silencer is effectively absorbed into the fibrous absorption material and converted into heat energy.
[0041] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only used to explain the relative position relationship, movement, etc. between the components in a certain posture. If the specific posture changes, the directional indication will also change accordingly. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.
[0042] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.
[0043] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.
Claims
1. A centrifugal fan blade tip micro-convex structure, characterized in that: It includes a plurality of blade protrusions arranged on the outer blades of the fan blade hub; The several blade protrusions include a first protrusion, a second protrusion and a third protrusion. Each of the blade protrusions is composed of four arc curves. The size parameters of the second protrusion and the third protrusion are consistent. The protrusion heights of the first protrusion, the second protrusion and the third protrusion are greater than 0.1 mm and less than 1 / 2 of the gap between the upper cover and the blade top.
2. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The fan blade hub diameter is 23.8-30.2mm.
3. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The outer diameter of the fan blade is 42-70 mm, and the thickness of a single blade is 0.2-0.8 mm.
4. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The fan blades rotate counterclockwise.
5. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The four endpoints of the curve of the blade protrusion are the intersection points of circular references of different diameters and the curves of the leading and trailing edges of the blades. The circular reference is formed by the central arc curve of each blade protrusion offset by a preset distance toward the tip and root directions, respectively. The central arc curve is an arc curve formed within the blade protrusion with the center point of the blade hub as the center and the radius from the center point of the blade hub to the center point of the blade protrusion.
6. The centrifugal fan blade tip micro-protrusion structure according to claim 5, characterized in that: The diameter of the central arc curve of the first protrusion is 0.8 to 0.9 times the outer diameter of the fan blade, the diameter of the central arc curve of the second protrusion is 0.9 to 0.95 times the outer diameter of the fan blade, and the diameter of the central arc curve of the third protrusion is 0.95 to 1 times the outer diameter of the fan blade.
7. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The first protrusion includes a first protrusion first curve, a first protrusion second curve, a first protrusion third curve and a first protrusion fourth curve, the first protrusion first curve, the first protrusion second curve, the first protrusion third curve and the first protrusion fourth curve are connected in sequence to form a quadrilateral, the width of the first protrusion is the same as the width of the blade, the first protrusion second curve and the first protrusion fourth curve are arc curves, and the first protrusion first curve and the first protrusion third curve are arc curves, straight lines or elliptical curves.
8. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The positions of the plurality of blade protrusions are arranged on the actual direction line of the flow field at the gap between the fan blade top and the upper cover.
9. The centrifugal fan blade tip micro-protrusion structure according to claim 1, characterized in that: The edge of the blade is provided with a silent ring.