Blade mounting angle optimization method

Abstract

The invention belongs to the technical field of design of small axial flow fans, and particularly relates to a blade mounting angle optimization method which is used for optimizing the mounting angle of blades of an axial flow fan. According to the method, the three-dimensional model of the fan is simplified, and simulation calculation is performed on the airflow characteristics of the fan by means of a numerical simulation method; meanwhile, fan blades are parameterized, the influence rule of blade parameters on the fan performance is determined, and the parameters are optimized to improve the fan airflow characteristic index. On the premise that other parameters of the fan blade are kept unchanged, the blade top mounting angle and the blade root mounting angle of the fan blade are adjusted, the complex flowing condition of a fan runner is improved, the design point efficiency of the fan is improved, and the aerodynamic performance of the fan is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of small axial flow fan design, and specifically relates to a blade installation angle optimization method. Background Art

[0002] Small axial fans are widely used in the field of electronic equipment heat dissipation due to their small size, low energy consumption, and easy installation. Under the same input power, fans with excellent aerodynamic performance such as large air volume and high air pressure have better heat dissipation effect, so how to optimize the fan blade shape to achieve excellent aerodynamic performance is a current hot research topic. Summary of the invention

[0003] In view of this, a blade installation angle optimization method is provided, which is used to optimize the installation angle of axial flow fan blades; the optimization method comprises the following steps:

[0004] S101: Obtaining experimental data related to the aerodynamic performance of the fan;

[0005] S102: establishing a numerical simulation model of the fan, wherein the features of the simulation model only include main features related to aerodynamic performance;

[0006] S103: performing at least one round of numerical simulation calculation on the simulation model, the numerical simulation including grid division and boundary condition setting, so that the calculation results fit the experimental data;

[0007] S104: assigning corresponding values ​​to the blade parameters of the simulation model after reverse parameterized numerical simulation calculation according to the three-dimensional geometry of the blade;

[0008] S105: Optimizing blade data on the simulation model assigned with corresponding numerical values, and then performing numerical simulation calculations;

[0009] S106: Repeat S105 to find the optimal installation angle of the blade.

[0010] Furthermore, the main features include hub geometric features, wheel cover geometric features, blade geometric features and air duct geometric features.

[0011] Furthermore, the corresponding values ​​of the parameters assigned to the blades include: installation angle, blade shape, blade length, blade thickness and blade meridian plane data.

[0012] Furthermore, the optimization data implemented on the blades include: the blade top installation angle and the blade root installation angle.

[0013] Furthermore, after S106, the step further includes:

[0014] S107: Perform reliability verification on the blade with the best performance.

[0015] Furthermore, the S107 is verified and implemented based on 3D printed blades and then installed on the hub.

[0016] Beneficial effects of the present invention:

[0017] Under the premise of keeping other parameters of the fan blades unchanged, the present invention adjusts the blade tip installation angle and the blade root installation angle of the fan blade, improves the complex flow conditions of the fan flow channel, improves the fan design point efficiency, and enhances the fan aerodynamic performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments 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 creative work.

[0019] Figure 1 This is a structural diagram of the blade rotor blade of the present invention;

[0020] Figure 2 A schematic diagram for setting the blade installation angle;

[0021] Figure 3 This is a performance curve comparison diagram of the new blade of the present invention and the original blade;

[0022] Figure 4 A comparison diagram of the leakage flow ratio between the new blade of the present invention and the original blade;

[0023] Figure 5 This is a cloud diagram of the high entropy, static pressure, total pressure and total temperature distribution of 90% of the new blades of the present invention. DETAILED DESCRIPTION

[0024] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0025] The following describes the embodiments of the present disclosure through specific examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present disclosure.

[0026] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0027] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present disclosure. The illustrations only show components related to the present disclosure rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0028] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described may be practiced without these specific details.

[0029] In one embodiment of the present invention, a blade installation angle optimization method is used to optimize the installation angle of an axial flow fan blade; the optimization method comprises the following steps:

[0030] S101: Obtaining experimental data related to the aerodynamic performance of the fan;

[0031] S102: establishing a numerical simulation model of the fan, wherein the features of the simulation model only include main features related to aerodynamic performance;

[0032] S103: performing at least one round of numerical simulation calculation on the simulation model, the numerical simulation including grid division and boundary condition setting, so that the calculation results fit the experimental data;

[0033] S104: assigning corresponding values ​​to the blade parameters of the simulation model after reverse parameterized numerical simulation calculation according to the three-dimensional geometry of the blade;

[0034] S105: Optimizing blade data on the simulation model assigned with corresponding numerical values, and then performing numerical simulation calculations;

[0035] S106: Repeat S105 to find the optimal installation angle of the blade.

[0036] In this embodiment, the main features include hub geometric features, wheel cover geometric features, blade geometric features and air duct geometric features.

[0037] 3. The blade installation angle optimization method according to claim 2 is characterized in that the corresponding numerical values ​​assigned to the blade parameters include: installation angle, blade shape, blade length, blade thickness and blade meridian plane data.

[0038] In this embodiment, the optimization data implemented on the blades include: a blade top installation angle and a blade root installation angle.

[0039] In this embodiment, after S106, the following steps are further performed:

[0040] S107: Perform reliability verification on the blade with the best performance.

[0041] In this embodiment, S107 is verified and implemented based on 3D printed blades and then installed on the hub.

[0042] The overall route for optimizing the blade profile in this embodiment is to simplify the three-dimensional model of the fan and simulate the fan airflow characteristics with the help of numerical simulation methods. At the same time, the fan blades are parameterized to determine the influence of blade parameters on fan performance, and the parameters are optimized to improve the fan airflow characteristic indicators. The optimized fan is tested and verified with 3D printing technology to verify the reliability of the numerical simulation optimization process. A new mold is designed for the fan blade model that meets the characteristic indicators in the test, and the optimization of the axial fan blades is completed to improve the aerodynamic performance. The fan blade optimization design process is as follows:

[0043] Step 1: Simplify the fan geometry. When building the fan numerical simulation model, retain the main features of the fan flow path and remove redundant geometry to avoid problems such as negative grids and multiple increases in the number of grids due to retaining too many subtle geometric features.

[0044] Step 2: Numerical simulation calculation, including mesh division and boundary condition setting. Verifying the number of simulation grids through grid independence can not only improve the simulation speed but also ensure the accuracy of calculation, thus verifying the reliability of numerical simulation;

[0045] Step 3: Reverse parameterize the blade and assign corresponding values ​​to the blade parameters according to the blade's three-dimensional geometry;

[0046] Step 4: Implement optimization, adjust the blade tip installation angle and blade root installation angle within the optimization range, and find the optimal blade installation angle through the numerical simulation calculation of step 2;

[0047] Step 5: Test verification, using 3D printing technology to verify the reliability of the blade with the best performance.

[0048] See also Figure 1-Figure 5 This embodiment simplifies the three-dimensional model of the fan and simulates the fan airflow characteristics with the help of numerical simulation methods. At the same time, the fan blades are parameterized to determine the influence of blade parameters on fan performance, and the parameters are optimized to improve the fan airflow characteristic indicators. The optimized fan is tested and verified with 3D printing technology to verify the reliability of the numerical simulation optimization process. A new mold is designed for the fan blade model that meets the characteristic indicators in the test, and the axial fan blade optimization work is completed to improve the aerodynamic performance.

[0049] The fan blade installation angle is closely related to the fan power coefficient, expansion pressure and fan aerodynamic throat. Therefore, this embodiment improves the fan performance by adjusting the blade installation angle. 1 =14.5°, the angle between the outer chord of the blade root airfoil and the blade line θ 2 =22.6. Based on the simulation results and power limit, the optimal range of blade installation angle is determined as follows: blade tip installation angle (10.5°, 18.5°), blade root installation angle (18.6°, 26.6°). The blade optimization design is implemented within this range, and the optimal blade installation angle is 18.5° and 26.6°.

[0050] The axial flow fan using the blades optimized by the blade installation angle optimization method of this embodiment has achieved improved aerodynamic performance in the entire operating range. According to experimental verification, the maximum air volume increased by 17.6% year-on-year, the maximum wind pressure increased by 13.7% year-on-year, and the design point efficiency increased by 2%. Changing the blade installation angle inhibits the propagation of the gap leakage vortex, improves the phenomenon of low-energy fluid group blocking the downstream of the channel, and increases the work capacity of the fan. At the same time, it improves the airflow stability at the fan outlet, reduces flow losses, and improves the fan efficiency.

[0051] The above is only a specific implementation of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A blade installation angle optimization method, characterized in that: Used to optimize the installation angle of axial flow fan blades; the optimization method comprises the following steps: S101: Obtaining experimental data related to the aerodynamic performance of the fan; S102: establishing a numerical simulation model of the fan, wherein the features of the simulation model only include main features related to aerodynamic performance; S103: performing at least one round of numerical simulation calculation on the simulation model, the numerical simulation including grid division and boundary condition setting, so that the calculation results fit the experimental data; S104: assigning corresponding values ​​to the blade parameters of the simulation model after reverse parameterized numerical simulation calculation according to the three-dimensional geometry of the blade; S105: Optimizing blade data on the simulation model assigned with corresponding numerical values, and then performing numerical simulation calculations; S106: Repeat S105 to find the optimal installation angle of the blade.

2. The blade installation angle optimization method according to claim 1, characterized in that: The main features include hub geometric features, wheel cover geometric features, blade geometric features and air duct geometric features.

3. The blade installation angle optimization method according to claim 2, characterized in that: The corresponding values ​​of the parameters assigned to the blades include: installation angle, blade shape, blade length, blade thickness and blade meridian plane data.

4. The blade installation angle optimization method according to claim 3, characterized in that: The optimized data for blades include: blade top installation angle and blade root installation angle.

5. The blade installation angle optimization method according to claim 4, characterized in that: After S106, the following steps are also included: S107: Perform reliability verification on the blade with the best performance.

6. The blade installation angle optimization method according to claim 5, characterized in that: The S107 is verified and implemented based on 3D printed blades and then installed on the hub.

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