Low noise centrifugal fan with vortex generators

Abstract

The utility model discloses a low -noise centrifugal fan with vortex generator, including volute and impeller, the volute has the flow channel space, the air outlet and the air inlet, the impeller rotatablely installs in the flow channel space, the air outlet of volute is provided with volute tongue and vortex generator, the vortex generator protrudes from the flow channel wall surface, and will flow channel space divide and form first flow channel and second flow channel for guiding airflow, through being provided with volute tongue and vortex generator at the air outlet of volute, the vortex generator protrudes from the flow channel wall surface, and will flow channel space divide and form first flow channel and second flow channel for guiding airflow, thus, realize the redistribution and segmentation of airflow, through the airflow at the air outlet is divided into a plurality of flow channels, and vortex generator can scatter large, unstable vortex into smaller, more stable microvortex, thereby reduce wide frequency noise.

Description

Technical Field

[0001] This utility model relates to the field of low-noise centrifugal fans, and in particular to a low-noise centrifugal fan with a vortex generator. Background Technology

[0002] For laptop fans, a good user experience highly depends on low noise operation. However, as the main active cooling component of a laptop, the noise of the fan is often a key factor affecting the user experience. Therefore, reducing the noise of laptop fans is of utmost importance.

[0003] In traditional centrifugal fans, the volute tongue of the flow channel is closest to the fan blades, and the volute tongue is a raised structure whose function is to guide the airflow thrown out of the impeller, collect it, and guide it to the outlet. However, this sharp volute tongue will have a strong periodic interaction with the rotating impeller blades, resulting in two main problems: 1. Aerodynamic noise: generating strong eddies and pressure pulsations, which is one of the main sources of fan noise; 2. Pressure loss: the sharp edge will disturb the airflow, leading to energy loss and reducing fan efficiency. Under current technological conditions, although the fluid design is close to the optimal solution under size constraints, the potential for further noise reduction is extremely limited. In a limited space, to significantly reduce noise while ensuring the same airflow, places extremely high demands on fan design. Existing fan designs can hardly meet customers' expectations for low noise.

[0004] Therefore, a new technical solution needs to be researched to address the above problems. Utility Model Content

[0005] In view of this, the present invention addresses the deficiencies of the existing technology, and its main objective is to provide a low-noise centrifugal fan with a vortex generator. By setting a volute tongue and a vortex generator at the air outlet of the volute, the vortex generator protrudes from the flow channel wall and divides the flow channel space into a first flow channel and a second flow channel for guiding airflow. In this way, the airflow is redistributed and divided. By dividing the airflow at the air outlet into multiple flow channels, the vortex generator can break up large, unstable vortices into smaller, more stable micro-vortices, thereby reducing broadband noise.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A low-noise centrifugal fan with a vortex generator includes a volute and an impeller; the volute has a flow channel space, an air outlet and an air inlet communicating with the flow channel space; the impeller is rotatably mounted within the flow channel space, characterized in that: The volute is provided with a volute tongue and a vortex generator for improving airflow and reducing aerodynamic noise at the air outlet. The vortex generator is a sheet-like structure of equal thickness. The vortex generator protrudes from the flow channel wall and divides the flow channel space to form a first flow channel and a second flow channel for guiding airflow.

[0007] As a preferred embodiment, the volute tongue has a windward side, and the leading edge of the vortex generator is disposed on the windward side to divide the flow channel space into a first flow channel and a second flow channel for guiding airflow. By directly placing the vortex generator on the windward side of the volute tongue where the airflow impact is most concentrated, it can directly intervene at the main source of noise and vortex generation, and can most effectively disperse the periodic large vortices formed at the volute tongue when the impeller blades sweep across, and optimize the airflow segmentation before leaving the flow channel, thereby achieving direct and efficient noise reduction from the source.

[0008] As a preferred embodiment, the volute includes a base plate, a side frame, and a top cover. The side frame is disposed on the base plate, and the top cover is closed on the base plate to form a flow channel space. The volute tongue protrudes from the inside of the side frame near the air outlet.

[0009] As a preferred embodiment, the angle between the vortex generator and the base plate is 5 to 18 degrees. By setting the vortex generator within this optimal angle range, the airflow can flow over the generator surface at the best angle of attack, which can minimize flow resistance and energy loss. At the same time, it ensures that the vortex generator achieves the best re-excitation effect on the boundary layer and the vortex segmentation effect, thereby achieving noise reduction while better maintaining or even improving the aerodynamic performance efficiency of the fan.

[0010] As a preferred embodiment, the vortex generator includes a mounting portion for installation on the windward side of the volute tongue and a planar portion for guiding airflow. The planar portion extends radially from the end of the mounting portion away from the volute tongue toward the flow channel space. The planar portion provides a smooth and efficient guiding surface, which can smoothly guide and divide the airflow, minimizing the obstruction and disturbance to the airflow caused by additional structures while ensuring noise reduction.

[0011] As a preferred embodiment, the center of the vortex generator is located at 25% to 75% of the axial height of the volute tongue, and the vortex generator is set in the middle main area of ​​the volute tongue axis so that its range of action can cover most of the main airflow channel.

[0012] As a preferred embodiment, the vortex generator is integrally formed on the windward side of the volute tongue. The integral forming process completely eliminates the problem of possible assembly gaps or loose connections between the vortex generator and the volute tongue, avoiding new abnormal noises or vortices caused by these gaps. This makes the airflow contact surface extremely smooth and flat, greatly reducing flow resistance and enhancing the structural strength and overall lifespan of the components.

[0013] As a preferred embodiment, the vortex generator protrudes from the base plate near the air outlet to divide the air outlet into a first air outlet channel and a second air outlet channel for guiding airflow.

[0014] As a preferred embodiment, the eddy current generator is integrally formed on the base plate.

[0015] Compared with the prior art, this utility model has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution, It mainly achieves air redistribution and segmentation by setting a volute tongue and a vortex generator at the air outlet of the volute. The vortex generator protrudes from the flow channel wall and divides the flow channel space into a first flow channel and a second flow channel for guiding airflow. In this way, the airflow is redistributed and segmented. By dividing the airflow at the air outlet into multiple flow channels, the vortex generator can break up large, unstable vortices into smaller and more stable micro vortices, thereby reducing broadband noise. Secondly, the vortex generator adopts a sheet-like structure of equal thickness, which makes the airflow segmentation effect stable and controllable, and is conducive to generating uniform small vortices; Then, the structure of the vortex generator protruding from the flow channel wall can re-excite the low-speed airflow (boundary layer) near the wall, allowing the airflow to adhere better to the volute wall, reducing airflow separation, and helping to reduce flow loss and improve wind pressure and efficiency. Furthermore, the vortex generator is located at the air outlet and works in conjunction with the volute tongue. It can mitigate the periodic pressure changes caused by the impeller blades passing through the volute tongue. By smoothing the airflow, the vortex generator makes the pressure changes more gradual, thereby reducing periodic noise.

[0016] To more clearly illustrate the structural features and effects of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a perspective view of one embodiment of the present utility model; Figure 2 This is a first side view of an embodiment of the present utility model; Figure 3 This is an exploded view of Embodiment 1 of this utility model; Figure 4 This is a second side view of Embodiment 1 of the present utility model; Figure 5 This is a third side view of Embodiment 1 of this utility model; Figure 6 This is the fourth side view of Embodiment 1 of this utility model; Figure 7This is a schematic diagram summarizing data at different included angles and different axial heights of the eddy current generator according to Embodiment 1 of this utility model; Figure 8 This is a schematic diagram of an embodiment of the present invention, showing an eddy current generator with an included angle of 15° and the eddy current generator located at the center of the volute tongue. Figure 9 This is a schematic diagram of an embodiment of the present invention, showing an eddy current generator with an included angle of 15° and the eddy current generator offset downward by 0.3mm from its central position. Figure 10 This is a schematic diagram of an embodiment of the present invention, showing an eddy current generator with an included angle of 10° and the eddy current generator offset downward by 0.3mm from its central position. Figure 11 This is a schematic diagram of an embodiment of the present invention, showing an eddy current generator with an included angle of 5° and the eddy current generator offset downward by 0.3mm from its central position. Figure 12 This is a comparison diagram of Embodiment 1 of this utility model with and without an eddy current generator; Figure 13 This is a schematic diagram of the noise and speed curves of different configurations of this utility model with and without an eddy current generator; Figure 14 This is a perspective view of Embodiment 2 of this utility model; Figure 15 This is a side view of Embodiment 2 of this utility model.

[0018] Explanation of reference numerals in the attached diagram: 10. Volute 11. Flow channel space 111. First flow channel; 112. Second flow channel 12. Air inlet 13. Air outlet 14. Volute tongue 15. Vortex generator 141. Windward side 151. Mounting section; 152. Flat section 101. Base plate; 102. Side frame 103. Top cover 16. First air outlet duct 17. Second air outlet duct 20. Impeller. Detailed Implementation

[0019] Please refer to Figures 1 to 15 As shown, it illustrates the specific structure of various embodiments of the present invention.

[0020] like Figures 1 to 13 As shown, it embodies the specific structure of this embodiment one.

[0021] In the description of this utility model, it should be noted that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0022] A low-noise centrifugal fan with a vortex generator 15 includes a volute 10 and an impeller 20. The volute 10 has a flow channel space 11, an air outlet 13 communicating with the flow channel space 11, and an air inlet 12; the impeller 20 is rotatably mounted within the flow channel space 11. Preferably, the volute 10 includes a base plate 101, a side frame 102 and a top cover 103. The side frame 102 is disposed on the base plate 101, and the top cover 103 covers the base plate 101 to form a flow channel space 11. The volute tongue 14 protrudes from the inside of the side frame 102 near the air outlet 13.

[0023] The volute 10 is provided with a volute tongue 14 and a vortex generator 15 for improving airflow and reducing aerodynamic noise at the air outlet 13. The vortex generator 15 protrudes from the flow channel wall and divides the flow channel space 11 to form a first flow channel 111 and a second flow channel 112 for guiding airflow.

[0024] Preferably, the volute tongue 14 has a windward side 141, and the leading edge of the vortex generator 15 is disposed on the windward side 141 to divide the flow channel space 11 into a first flow channel 111 and a second flow channel 112 for guiding airflow. By directly placing the vortex generator 15 on the windward side 141 of the volute tongue 14 where the airflow impact is most concentrated, it can directly intervene from the main source of noise and vortex generation, and can most effectively disperse the periodic large vortex formed at the volute tongue 14 when the impeller 20 blades sweep across, and optimize the airflow segmentation before leaving the flow channel, thereby achieving direct and efficient noise reduction from the source.

[0025] Preferably, the vortex generator 15 is integrally formed on the windward side 141 of the volute tongue 14. The integral forming process completely eliminates the problem of possible assembly gaps or loose connections between the vortex generator 15 and the volute tongue 14, avoiding new abnormal noises or vortices caused by these gaps. This makes the airflow contact surface extremely smooth and flat, greatly reducing flow resistance and enhancing the structural strength and overall lifespan of the components.

[0026] Preferably, the vortex generator 15 is a sheet-like structure of equal thickness. The use of a sheet-like structure of equal thickness makes the airflow segmentation effect stable and controllable, which is conducive to generating uniform small vortices. On the other hand, the structure is simple and easy to process and manufacture.

[0027] The angle between the vortex generator 15 and the base plate is 5 to 18 degrees. Preferably, the angle between the vortex generator 15 and the base plate is 12 to 18 degrees. By setting the vortex generator 15 within this optimal angle range, the airflow can flow over the generator surface at the best angle of attack, which can minimize flow resistance and energy loss. At the same time, it ensures that the re-excitation effect of the vortex generator 15 on the boundary layer and the vortex segmentation effect reach the best state, thereby achieving noise reduction while better maintaining or even improving the aerodynamic performance efficiency of the fan.

[0028] Preferably, the vortex generator 15 includes a mounting portion 151 for mounting on the windward side 141 of the volute tongue 14 and a planar portion 152 for guiding airflow. The planar portion 152 extends radially from the end of the mounting portion 151 away from the volute tongue 14 toward the flow channel space 11. The planar portion 152 provides a smooth and efficient guiding surface, which can smoothly guide and divide the airflow, minimizing the obstruction and disturbance to the airflow caused by the additional structure while ensuring the noise reduction effect.

[0029] Preferably, the center of the vortex generator 15 is located at 25% to 75% of the axial height of the volute tongue 14, and the vortex generator 15 is set in the middle main area of ​​the volute tongue 14 axial direction so that its range of action can cover most of the main airflow channel.

[0030] like Figures 14 to 15 As shown, this illustrates Embodiment Two, which differs from Embodiment One in that: The vortex generator 15 protrudes from the base plate 101 near the air outlet 13, dividing the air outlet 13 into a first air outlet channel 16 and a second air outlet channel 17 for guiding airflow. Preferably, the vortex generator 15 is integrally formed on the base plate 101.

[0031] The key design feature of this invention is that it mainly involves setting a volute tongue and a vortex generator at the air outlet of the volute. The vortex generator protrudes from the flow channel wall and divides the flow channel space into a first flow channel and a second flow channel for guiding airflow. In this way, the airflow is redistributed and divided. By dividing the airflow at the air outlet into multiple flow channels, the vortex generator can break up large, unstable vortices into smaller, more stable micro-vortices, thereby reducing broadband noise. Secondly, the vortex generator adopts a sheet-like structure of equal thickness, which makes the airflow segmentation effect stable and controllable, and is conducive to generating uniform small vortices; Next, the structure of the vortex generator protruding from the flow channel wall can re-excite the low-speed airflow (boundary layer) near the wall, allowing the airflow to adhere better to the volute wall, reducing airflow separation, which helps to reduce flow loss and improve wind pressure and efficiency. Furthermore, the vortex generator is located at the air outlet and works in conjunction with the volute tongue to mitigate the periodic pressure changes caused by the impeller blades passing through the volute tongue. By smoothing the airflow transition, the vortex generator makes the pressure changes more gradual, thereby reducing periodic noise.

[0032] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A low-noise centrifugal fan with a vortex generator, comprising a volute and an impeller; the volute having a flow channel space, an air outlet communicating with the flow channel space, and an air inlet; the impeller being rotatably mounted within the flow channel space, characterized in that: The volute is provided with a volute tongue and a vortex generator for improving airflow and reducing aerodynamic noise at the air outlet. The vortex generator is a sheet-like structure of equal thickness. The vortex generator protrudes from the flow channel wall and divides the flow channel space to form a first flow channel and a second flow channel for guiding airflow.

2. The low-noise centrifugal fan with an eddy current generator according to claim 1, characterized in that: The volute tongue has a windward side, and the leading edge of the vortex generator is located on the windward side to divide the flow channel space into a first flow channel and a second flow channel for guiding airflow.

3. The low-noise centrifugal fan with an eddy current generator according to claim 1, characterized in that: The volute includes a base plate, a side frame, and a top cover. The side frame is disposed on the base plate, and the top cover is closed on the base plate to form a flow channel space. The volute tongue protrudes from the inside of the side frame near the air outlet.

4. The low-noise centrifugal fan with an eddy current generator according to claim 3, characterized in that: The angle between the eddy current generator and the base plate is 5 to 18 degrees.

5. The low-noise centrifugal fan with an eddy current generator according to claim 1, characterized in that: The vortex generator includes a mounting portion for mounting on the windward side of the volute tongue and a planar portion for guiding airflow, the planar portion extending radially from the end of the mounting portion away from the volute tongue toward the flow channel space.

6. The low-noise centrifugal fan with an eddy current generator according to claim 1, characterized in that: The center of the vortex generator is located at 25% to 75% of the axial height of the volute tongue.

7. The low-noise centrifugal fan with an eddy current generator according to claim 2, characterized in that: The vortex generator is integrally formed on the windward side of the volute tongue.

8. The low-noise centrifugal fan with an eddy current generator according to claim 3, characterized in that: The vortex generator protrudes from the base plate near the air outlet to divide the air outlet into a first air outlet channel and a second air outlet channel for guiding airflow.

9. The low-noise centrifugal fan with an eddy current generator according to claim 8, characterized in that: The eddy current generator is integrally formed on the base plate.

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