Centrifugal fan for a range hood and range hood

Abstract

This utility model relates to the field of household appliances, specifically to a centrifugal fan for a range hood, comprising a volute (1) defining an air cavity (110) and an air outlet (120) communicating with the air cavity (110). The volute (1) includes a volute tongue (11) disposed at the air outlet (120). The volute tongue (11) includes an inner guide surface (111) facing the air cavity (110), an outer guide surface (112) facing the air outlet (120), and a tongue tip curved surface (113) connecting the inner guide surface (111) and the outer guide surface (112). A plurality of vortex generators (2) are disposed at the outer guide surface (112) of the volute tongue (11). Through the technical solution of this utility model embodiment, the airflow separation occurring at the volute tongue of the centrifugal fan can be effectively suppressed with a simple structure, thereby improving the aerodynamic efficiency of the centrifugal fan. This utility model also relates to a corresponding range hood.

Description

Technical Field

[0001] The embodiments of this utility model relate to the field of household appliances, and more specifically to a centrifugal fan for a range hood and a corresponding range hood. Background Technology

[0002] Due to varying working conditions, centrifugal fans used in range hoods generally have a wide operating range, thus requiring high performance across all operating conditions. Existing technologies typically improve the aerodynamic performance of centrifugal fans by modifying the volute profile or impeller design. However, these improvements are often only effective for certain operating conditions and are unlikely to cover the entire range, especially under high-resistance (low-flow) conditions, where severe flow separation at the centrifugal fan outlet significantly reduces aerodynamic efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a centrifugal fan for a range hood and a corresponding range hood. At least one embodiment of this invention can at least partially overcome the aforementioned deficiencies in the prior art.

[0004] According to one embodiment of the present invention, a centrifugal fan for a range hood is provided. The centrifugal fan includes a volute, the volute defining an air cavity and an air outlet communicating with the air cavity. The volute includes a volute tongue disposed at the air outlet. The volute tongue includes an inner guide surface facing the air cavity, an outer guide surface facing the air outlet, and a tongue tip curved surface connecting the inner guide surface and the outer guide surface. A plurality of vortex generators are disposed at the outer guide surface of the volute tongue.

[0005] This embodiment enables the aerodynamic efficiency of a centrifugal fan to be improved by using multiple vortex generators installed on the outer guide surface of the volute tongue to suppress flow separation occurring at the outer guide surface of the volute tongue, based on the flow field characteristics of the centrifugal fan.

[0006] The extensions and improvements to the technical solution of this utility model can be obtained from the following optional embodiments.

[0007] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the plurality of vortex generators are arranged adjacent to the connecting line between the outer guide surface and the tongue-shaped curved surface and are aligned along the extending direction of the connecting line. This embodiment enables the suppression of flow separation as much as possible at the region where flow separation begins and along substantially the entire width of the outer guide surface.

[0008] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, each of the plurality of vortex generators has an installation angle inclined relative to the incoming direction of the airflow. With this embodiment, a pressure difference can be created between the two surfaces of the vortex generator by means of the angle between the vortex generator and the airflow. This pressure difference causes the airflow on the high-pressure side to be drawn towards the low-pressure side, forming a vortex flowing closely against the outer guide surface, thereby suppressing flow separation and improving the aerodynamic efficiency of the fan.

[0009] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the plurality of vortex generators are arranged in pairs to form multiple pairs of vortex generators. Two vortex generators in each pair are arranged axially symmetrically about an axis extending along the incoming flow direction, and are arranged further apart from each other as they travel along the incoming flow direction. With this embodiment, stable and balanced vortex pairs can be generated by means of multiple pairs of vortex generators, reliably suppressing flow separation.

[0010] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the installation angle ranges from 12° to 18°. This embodiment allows for better suppression of flow separation.

[0011] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the centrifugal fan has a drive device that is kinetically connected to the plurality of vortex generators, and the vortex generators are configured to move and remain between a first position flush with the surface of the outer guide surface and a second position fully protruding from the surface of the outer guide surface by means of the drive device. With this embodiment, the height at which the vortex generator protrudes from the outer guide surface can be adjusted as needed, thereby better suppressing airflow separation in a suitable manner, while avoiding the vortex generator obstructing normal airflow and causing abnormal noise due to excessive protrusion height.

[0012] According to an alternative embodiment of the centrifugal fan for a range hood of the present invention, each pair of vortex generators or each vortex generator among the plurality of vortex generators is adapted to be driven individually. This embodiment allows for appropriate adjustment of the position of each vortex generator or each pair of vortex generators as needed, thereby better suppressing airflow separation for various operating conditions.

[0013] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the protrusion height of the vortex generator at the second position is 7-10 mm. This embodiment enables the suppression of airflow separation over a wider range of operating conditions.

[0014] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the centrifugal fan has a control device and a detection device. The detection device is configured to detect airflow state data that characterizes the separation state between the airflow at the air outlet and the outer guide surface. The control device is configured to control the drive device based on the airflow state data to adjust the dwell position of each pair of vortex generators or each vortex generator between the first position and the second position. Through this embodiment, the position of the vortex generators can be automatically adjusted in real time according to the operating conditions of the centrifugal fan, thereby more appropriately and effectively suppressing flow separation and improving the aerodynamic efficiency of the fan.

[0015] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the centrifugal fan further includes a rotary drive device configured to drive the vortex generator to rotate when the vortex generator is in the second position, and the control device is further configured to control the rotary drive device to adjust the installation angle of the plurality of vortex generators based on the airflow state data when the vortex generator is in the second position. Through this embodiment, flow separation can be suppressed over a wider range of operating conditions and the aerodynamic efficiency of the fan can be improved by further adjusting the installation angle of the vortex generator at the second position.

[0016] According to an optional embodiment of the centrifugal fan for a range hood of the present invention, the airflow state data includes static pressure distribution data on the outer guide surface and / or airflow velocity data. Through this embodiment, the position and installation angle of each vortex generator or each pair of vortex generators can be adjusted based on the static pressure distribution data on the outer guide surface and / or the airflow velocity data, thus enabling more appropriate and effective suppression of flow separation under various operating conditions and improving the aerodynamic efficiency of the fan.

[0017] According to one embodiment of the present invention, a range hood is also provided, which includes a centrifugal fan for a range hood according to an embodiment of the present invention.

[0018] Further features of this invention will become apparent from the claims, drawings, and description of the figures. Features and combinations of features mentioned in the foregoing description, as well as features and combinations of features mentioned in the following description of the figures and / or shown only in the figures, can be used not only in the correspondingly specified combinations, but also in other combinations without departing from the scope of this invention. Therefore, the following are also considered to be covered and disclosed by this invention: those not explicitly shown in the figures and not explicitly interpreted, but rather derived from and produced by combinations of separate features derived from the interpreted content. The following combinations of features are also considered to be disclosed: those that do not possess all the features of the originally drafted independent claims. Furthermore, the following combinations of features are considered to be disclosed, especially those exceeding or deviating from the feature combinations defined in the reference relationships of the claims. Attached Figure Description

[0019] The present invention will now be described in more detail with reference to the accompanying drawings, which will provide a better understanding of its principles, features, and advantages. The drawings include:

[0020] Figure 1 A perspective view of a centrifugal fan for a range hood according to an embodiment of the present invention is shown schematically.

[0021] Figure 2 The arrangement of the vortex generator of a centrifugal fan for a range hood according to one embodiment of the present invention is schematically shown.

[0022] Figure 3A and Figure 3B The diagrams schematically illustrate the states of the centrifugal fan vortex generator of a range hood according to an embodiment of the present invention in the second and first positions, respectively.

[0023] List of reference numerals

[0024] 100 centrifugal fan

[0025] 1. Snail shell

[0026] 101 First sidewall

[0027] 102 Second sidewall

[0028] 103 Ring Wall

[0029] 11 volute tongue

[0030] 111 Inner guide surface

[0031] 112 External guide surface

[0032] 113 Tongue tip curved surface

[0033] 110 air cavity

[0034] 120 air outlet

[0035] 2. Eddy current generator

[0036] 3 Impeller

[0037] 4 motors

[0038] L connecting line

[0039] D. Direction of Flow Detailed Implementation

[0040] To make the technical problem to be solved, the technical solution, and the beneficial technical effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and several exemplary embodiments. It should be understood that the specific embodiments described herein are only for explaining the present utility model and are not intended to limit the scope of protection of the present utility model. It should be noted that the directional terms used in the description refer to the conventional use of the range hood for ease of description and should not be construed as absolute limitations on the corresponding features.

[0041] Figure 1 A perspective view of a centrifugal fan 100 for a range hood according to an embodiment of the present invention is shown schematically. Figure 2 The arrangement of the vortex generator 2 of a centrifugal fan 100 for a range hood according to one embodiment of the present invention is shown schematically. Figure 3A and Figure 3B The diagrams schematically illustrate the states of the vortex generator 2 of the centrifugal fan 100 of the range hood according to an embodiment of the present invention in the second position and the first position, respectively.

[0042] like Figures 1 to 3BAs shown, a centrifugal fan 100 for a range hood according to an embodiment of the present invention includes a volute 1. The volute 1 is composed of a first sidewall 101, a second sidewall 102, and an annular wall 103. The annular wall 103 is disposed between the first sidewall 101 and the second sidewall 102 and connects the first sidewall 101 and the second sidewall 102, thereby defining an internal air cavity 110 and an air outlet 120 communicating with the air cavity 110 by the first sidewall 101, the second sidewall 102, and the annular wall 103. The volute 1 includes a volute tongue 11 disposed at the air outlet 120. The volute tongue 11 includes an inner guide surface 111 facing the air cavity 110, an outer guide surface 112 facing the air outlet 120, and a tongue tip curved surface 113 connecting the inner guide surface 111 and the outer guide surface 112. The centrifugal fan 100 also includes an impeller 3 and a motor 4 that drives the impeller. Both are located in the air chamber 110. The motor 4 drives the impeller 3 to rotate to do work on the gas that enters the impeller 3 axially, and then discharges it radially from the air outlet 120 through the diffusion effect of the volute 1.

[0043] Due to varying exhaust environments, range hoods operate under different conditions depending on the resistance of the exhaust duct. Fluid simulations under multiple conditions revealed that, particularly under high back pressure, flow separation occurs to varying degrees at the outer guide surface 112 of the volute tongue 11. To minimize this flow separation, the centrifugal fan 100 of this invention incorporates multiple vortex generators 2 located at the outer guide surface 112 of the volute tongue 11, enabling the centrifugal fan 100 to maintain good aerodynamic efficiency under various operating conditions.

[0044] In a preferred embodiment, particularly as Figure 2 As shown, multiple vortex generators 2 are positioned adjacent to the connecting line L between the outer guide surface 112 and the tongue-shaped curved surface 113 and are arranged along the extending direction of the connecting line L. In this way, the vortex generators 2 can be positioned in the region on the outer guide surface 112 where flow separation begins to occur, and flow separation can be effectively prevented in substantially the entire width direction of the outer guide surface 112.

[0045] In a preferred embodiment, such as Figure 2 As shown, each of the plurality of vortex generators 2 has an installation angle inclined relative to the incoming flow direction D of the airflow. In this way, the angle between the vortex generator 2 and the incoming flow direction D of the airflow allows a pressure difference to exist between the two surfaces of the vortex generator 2. The gas on the high-pressure side will be drawn to the other side at the upper edge, thereby forming a vortex. The vortex then flows closely along the outer guide surface 112, thereby reducing flow separation.

[0046] In a preferred embodiment, such as Figure 2As shown, multiple vortex generators 2 are arranged in pairs to form multiple pairs of vortex generators 2. The two vortex generators 2 in each pair are arranged axially symmetrically about an axis extending along the incoming flow direction D, and are arranged further apart from each other as they travel along the incoming flow direction D. Thus, a structurally stable and balanced vortex pair can be formed by means of the paired vortex generators 2. Such a vortex pair can extend downstream continuously for a long distance along the outer guide surface 112 without rapid dissipation, thereby significantly reducing the occurrence of flow separation.

[0047] In a preferred embodiment, the installation angle of each vortex generator 2 relative to the incoming flow direction D ranges from 12° to 18°, for example, 15°. Alternatively, the initial installation angle of the vortex generator 2 is 15°, and it can be adjusted at specific locations within an angle range of, for example, 12° to 18°, as detailed below. Such an installation angle range can better suppress the occurrence of flow separation.

[0048] In a preferred embodiment, the centrifugal fan 100 has a drive mechanism that is driveably connected to a plurality of vortex generators 2, and the vortex generators 2 are configured to be driven by the drive mechanism to a first position flush with the surface of the outer guide surface 112 (e.g., Figure 3B (as shown) and a second position that fully protrudes from the surface of the outer guide surface 112 (as shown) Figure 3A The vortex generator 2 can move and stay between the two positions (as shown). Therefore, the protrusion height of the vortex generator 2 from the surface of the outer guide surface 112 can be appropriately set according to different operating conditions. For example, under high back pressure conditions, the vortex generator 2 can be set to a second position where it fully protrudes from the surface of the outer guide surface 112 using a drive device, allowing the vortex generator 2 to fully function and suppress flow separation. Under low back pressure conditions, flow separation generally does not occur, and the vortex generator 2 can be returned to a first position flush with the surface of the outer guide surface 112. This prevents the vortex generator 2 from becoming an obstacle in the flow field and from generating abnormal noise. Of course, depending on the specific operating conditions, the vortex generator 2 can also stay at multiple positions between the first and second positions with different protrusion heights, thereby suppressing flow separation for various operating conditions. In an optional embodiment, the protrusion height of the vortex generator 2 at the second position is 7–10 mm. Of course, other sizes can be used as needed, as long as the vortex generator can effectively suppress flow separation.

[0049] In a preferred embodiment, each pair of vortex generators 2 or each vortex generator 2 among the plurality of vortex generators 2 is adapted to be driven individually. This allows for appropriate suppression of flow separation for more complex operating conditions. For example, due to varying degrees of flue blockage or other possible reasons, the degree of flow separation along the width of the outer guide surface 112 may differ. In such cases, the position of the relevant vortex generator 2 can be individually adjusted to effectively suppress flow separation while preventing other vortex generators 2 from obstructing airflow.

[0050] To better determine the position of each vortex generator 2 and thus more appropriately and effectively suppress flow separation, in a preferred embodiment, the centrifugal fan 100 has a control device and a detection device. The detection device is configured to detect airflow state data characterizing the separation state between the airflow at the outlet 120 and the outer guide surface 112, and the control device is configured to control the drive device to adjust the dwell position of each pair of vortex generators 2 or each vortex generator 2 between a first position and a second position based on the airflow state data. This allows the protrusion height of each vortex generator 2 to be automatically set based on the airflow state data, thereby suppressing flow separation in an appropriate configuration. In an optional embodiment, the airflow state data includes static pressure distribution data of the outer guide surface 112 and / or airflow velocity data. In one example, the relative protrusion height between the multiple vortex generators 2 can be determined based on the static pressure distribution data, and the dwell position of each vortex generator 2 between the first position and the second position can be determined based on the airflow velocity data.

[0051] In a preferred embodiment, the centrifugal fan 100 further includes a rotary drive device configured to drive the vortex generator 2 to rotate when the vortex generator 2 is in the second position, and a control device configured to control the rotary drive device to adjust the installation angle of the plurality of vortex generators 2 based on airflow state data when the vortex generator 2 is in the second position. As described above, the vortex generator 2 can have an initial installation angle of 15°, that is, the installation angle of the vortex generator 2 is maintained at 15° between the first position and the second position, while in the second position, the vortex generator 2 protrudes completely from the surface of the outer guide surface 112, and can therefore rotate within an angle range of, for example, 12° to 18°, thereby enabling further adjustment of its suppression effect on flow separation by adjusting the angle between the vortex generator 2 and the incoming flow direction D.

[0052] Although specific embodiments have been described above, these embodiments are not intended to limit the scope of this utility model, even when only a single embodiment is described with respect to a particular feature. The feature examples provided in this utility model disclosure are intended to be illustrative and not limiting, unless otherwise stated. In specific implementations, multiple features may be combined with each other as needed and where technically feasible. Various substitutions, modifications, and alterations may also be conceived without departing from the spirit and scope of this utility model.

Claims

1. A centrifugal fan for a range hood, characterized in that, The centrifugal fan (100) includes a volute (1) defining an air chamber (110) and an air outlet (120) communicating with the air chamber (110), wherein, The volute (1) includes a volute tongue (11) disposed at the air outlet (120). The volute tongue (11) includes an inner guide surface (111) facing the air cavity (110), an outer guide surface (112) facing the air outlet (120), and a tongue tip curved surface (113) connecting the inner guide surface (111) and the outer guide surface (112). Multiple vortex generators (2) are disposed at the outer guide surface (112) of the volute tongue (11).

2. The centrifugal fan for a range hood according to claim 1, characterized in that, The plurality of vortex generators (2) are disposed adjacent to the connecting line (L) between the outer guide surface (112) and the tongue-shaped curved surface (113) and are arranged along the extension direction of the connecting line (L).

3. The centrifugal fan for a range hood according to claim 2, characterized in that, Each of the plurality of vortex generators (2) has an installation angle tilted relative to the incoming direction (D) of the airflow.

4. The centrifugal fan for a range hood according to claim 3, characterized in that, The plurality of vortex generators (2) are arranged in pairs to form multiple pairs of vortex generators (2), and the two vortex generators (2) in each pair are arranged axially symmetrically about an axis extending along the incoming flow direction (D), and are arranged further apart from each other as they travel along the incoming flow direction (D); and / or The installation angle ranges from 12° to 18°.

5. The centrifugal fan for a range hood according to any one of claims 1 to 4, characterized in that, The centrifugal fan (100) has a drive device that is drively connected to the plurality of vortex generators (2), and the vortex generators (2) are configured to move and stay between a first position flush with the surface of the outer guide surface (112) and a second position that is fully protruding from the surface of the outer guide surface (112) by means of the drive device.

6. The centrifugal fan for a range hood according to claim 5, characterized in that, Each pair of eddy current generators (2) or each eddy current generator (2) among the plurality of eddy current generators (2) is adapted to be driven individually; and / or At the second position, the protrusion height of the eddy current generator (2) is 7-10 mm.

7. The centrifugal fan for a range hood according to claim 6, characterized in that, The centrifugal fan (100) has a control device and a detection device, the detection device being configured to detect airflow state data characterizing the separation state between the airflow at the outlet (120) and the outer guide surface (112), and The control device is configured to control the drive device to adjust the dwell position of each pair of vortex generators (2) or each vortex generator (2) between the first position and the second position based on the airflow state data.

8. The centrifugal fan for a range hood according to claim 7, characterized in that, The centrifugal fan (100) also has a rotary drive device configured to drive the vortex generator (2) to rotate when the vortex generator (2) is in the second position, and The control device is also configured to control the rotary drive device to adjust the installation angle of the plurality of vortex generators (2) based on the airflow state data when the vortex generator (2) is in the second position.

9. The centrifugal fan for a range hood according to claim 7 or 8, characterized in that, The airflow state data includes static pressure distribution data of the outer guide surface (112) and / or airflow velocity data.

10. A range hood characterized by, The range hood is integrated with a centrifugal fan (100) for use in a range hood according to any one of claims 1 to 9.

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