High-efficiency low-noise mixed-flow fan

Abstract

The utility model relates to a ventilation equipment technical field, proposes a kind of efficient low-noise mixed flow fan, including fan shell, fixed base, impeller and motor. Fan air inlet is equipped with pressure measuring point;Fixed base is located in the inside of fan shell, its circumferential direction is equipped with multiple guide vanes;Impeller is mixed flow impeller, is located in the front of guide vane, and its blade is three-dimensional space curved surface;Motor is transmission connection with impeller. The utility model cooperates through mixed flow impeller and guide vane, has the advantages of high wind pressure, large wind volume and high efficiency, and guide vane effectively rectifies and reduces noise;Through the linkage of pressure measuring point and frequency conversion motor, the automatic accurate control of air volume is realized. The fan structure is compact, stable in operation, especially suitable for air conditioner box and the occasion with higher requirements to wind pressure, noise and efficiency.

Description

Technical Field

[0001] This utility model relates to the field of ventilation equipment technology, specifically to a high-efficiency, low-noise mixed-flow fan. Background Technology

[0002] Currently, centrifugal fans without volutes or airfoil axial fans are commonly used in air conditioning units or fan walls. When centrifugal fans without volutes operate in parallel, they are prone to airflow interference, leading to decreased system efficiency and increased noise. While airfoil axial fans have a simple structure, they suffer from insufficient air pressure and low efficiency. Therefore, there is a lack of a fan product in the current technology that can provide both high air pressure and low noise and high efficiency. Utility Model Content

[0003] The purpose of this utility model is to overcome the shortcomings of the prior art and provide a high-efficiency, low-noise mixed-flow fan. By optimizing the matching structure of the impeller and guide vanes and introducing an intelligent air volume adjustment mechanism, it achieves high air pressure, high efficiency and low noise operation.

[0004] The technical solution of this utility model is as follows: A high-efficiency, low-noise mixed-flow fan includes a fan housing, a fixed base, an impeller, and a motor. The fan housing has an air inlet, and a pressure measuring point is provided at the air inlet. The fixed base is located inside the fan housing and has multiple guide vanes arranged circumferentially. The impeller is a mixed-flow impeller, located in front of the guide vanes, and its blades are three-dimensional curved surfaces. The motor is drivenly connected to the impeller.

[0005] Preferably, the pressure measuring point is connected to a pressure sensor, the motor is a variable frequency motor and is equipped with an electronic control unit, which adjusts the motor speed according to the pressure sensor signal.

[0006] Preferably, the impeller has a hub ratio of 0.35-0.55.

[0007] Preferably, the impeller has 7-13 blades.

[0008] Preferably, the number of guide vanes is 11-17.

[0009] Preferably, the installation angle of the guide vane is adjustable relative to the fan axis, with an adjustment range of 15°-40°.

[0010] The beneficial effects of this utility model are as follows: This invention, through the combination of a mixed-flow impeller and a spatial guide vane, significantly improves air pressure while maintaining the large air volume advantage of axial flow fans, resulting in high overall efficiency. The guide vanes rectify the rotating airflow at the impeller outlet, effectively reducing eddy and turbulent noise and achieving low-noise operation. By using closed-loop control of pressure measurement points and variable frequency motors, the air volume can be automatically and precisely adjusted to adapt to changes in system resistance, resulting in significant energy savings. With its compact overall structure, it is especially suitable for applications with multiple fans connected in parallel, which can avoid airflow interference and improve system stability. Attached Figure Description

[0011] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0012] Figure 1 This is a schematic diagram of the overall device of this utility model; Figure 2 This is a schematic diagram of the air inlet and pressure measuring point of this utility model; Figure 3 This is a schematic diagram of the impeller of this utility model; Figure 4 This is a schematic diagram of the fixing base and guide vane of this utility model; Figure 5 This is a schematic diagram of the motor of this utility model; In the diagram: 1. Fan casing; 11. Air inlet; 12. Pressure measuring point; 2. Mounting base; 21. Guide vane; 3. Impeller; 4. Motor. Detailed Implementation

[0013] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this utility model.

[0014] like Figures 1-5 As shown, the high-efficiency, low-noise mixed-flow fan of this utility model includes a cylindrical fan housing 1, one end of which is an air inlet 11. A pressure measuring point 12 is provided at the air inlet 11 for collecting the intake pressure signal.

[0015] An impeller 3 and a fixed base 2 are arranged axially inside the fan casing 1. The impeller 3 is a mixed-flow impeller, and its blades are three-dimensional curved surfaces optimized for aerodynamic performance. It can impart radial acceleration to the airflow while simultaneously allowing axial air intake, thus possessing both large air volume and high air pressure characteristics. The hub ratio of the impeller 3 is preferably 0.4-0.5, and the number of blades is 9-11.

[0016] The mounting base 2 is fixed to the inner wall of the fan casing 1, and multiple guide vanes 21 are evenly arranged around its circumference. The guide vanes 21 are spatially twisted plate-like structures, with their inlet angle matching the airflow direction at the impeller 3 outlet. They are used to convert the rotational kinetic energy of the airflow into static pressure and guide the airflow axially outward, thereby reducing energy loss and aerodynamic noise. The number of guide vanes 21 is preferably 13-15, and their installation angle is adjustable to adapt to different operating conditions.

[0017] The motor 4 is mounted at the center of the fixed base 2 or outside the fan housing 1, and is connected to the impeller 3 via a shaft to drive its rotation. The motor 4 is preferably a variable frequency motor.

[0018] This utility model can also be equipped with an intelligent control system, including a pressure sensor and an electronic control unit (not shown in the figure). The pressure measuring point 12 is connected to the pressure sensor. The electronic control unit calculates the air volume value in real time based on the pressure sensor signal and the built-in fan performance curve, and stabilizes the actual air volume of the fan at the set value by adjusting the speed of the motor 4, thereby achieving constant air volume control. Mixed-flow fan design and parameters: Design requirements: Pressure 1000Pa, impeller outer diameter 500mm.

[0019] Design flow rate: 5300 m³ / h; Design speed: 2418 rpm.

[0020] Actual design results: flow rate 5300 m3 / s, total pressure 1061.7 Pa, speed 2418 rpm, total pressure efficiency 84.50%.

[0021] Computational model: The following table shows the main structural parameters and dimensions: Moving leaves: Blade inlet installation angle / ° 30 Blade outlet installation angle / ° 44 Blade wrap angle / ° 65 Number of leaves 6 Axis tilt angle / ° 45 Blade axial length / mm 152 Channel axial length / mm 180 Blade tip clearance / mm 3 Guide vane: Blade inlet installation angle / ° 34.5 Blade outlet installation angle / ° 90 Blade wrap angle / ° 30 Number of leaves 11 Blade axial length / mm 231 Channel axial length / mm 300 The blade inlet is equipped with a shroud, which is an elliptical shroud with a major axis of 75mm and a minor axis of 50mm.

[0022] The inlet and outlet sections are extended by 2 and 3 times the diameter, respectively, with an inlet length of 1000 mm and an outlet length of 1500 mm. The calculation uses approximately 2 million grid cells for the moving blades, 1.5 million for the guide vanes, 1 million for the inlet section, and 1.5 million for the outlet section, all using structured mesh generation.

[0023] Observing the streamline diagram inside the impeller, it can be seen that there is almost no obvious flow separation inside the moving blade, and the flow field is good. There are vortices in the guide vane at the low section (blade root), which is unavoidable. However, since the flow velocity at the blade root is relatively low, the impact on the fan efficiency is small. The flow velocity at the blade tip is relatively high, which has a greater impact on the fan efficiency. Since there is almost no obvious flow separation at the high section (blade tip), the flow field is good.

[0024] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A high-efficiency, low-noise mixed-flow fan, comprising a fan housing (1), a mounting base (2), an impeller (3), and a motor (4), characterized in that: The fan housing (1) has an air inlet (11), and a pressure measuring point (12) is provided at the air inlet (11); the fixed base (2) is located inside the fan housing (1), and multiple guide vanes (21) are provided around it; the impeller (3) is a mixed-flow impeller, located in front of the guide vanes (21), and its blades are three-dimensional curved surfaces; the motor (4) is connected to the impeller (3) for transmission.

2. The high-efficiency, low-noise mixed-flow fan according to claim 1, characterized in that, The pressure measuring point (12) is connected to a pressure sensor. The motor (4) is a variable frequency motor and is equipped with an electronic control unit. The electronic control unit adjusts the speed of the motor (4) according to the pressure sensor signal.

3. The high-efficiency, low-noise mixed-flow fan according to claim 1, characterized in that, The impeller (3) has a hub ratio of 0.35-0.

55.

4. The high-efficiency, low-noise mixed-flow fan according to claim 3, characterized in that, The impeller (3) has 7-13 blades.

5. A high-efficiency, low-noise mixed-flow fan according to claim 1, characterized in that, The number of guide vanes (21) is 11-17.

6. A high-efficiency, low-noise mixed-flow fan according to claim 1 or 5, characterized in that, The installation angle of the guide vane (21) relative to the fan axis is adjustable, with an adjustment range of 15°-40°.

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