A high-uniform air velocity blowing device and an indoor blowing test method

Abstract

The application relates to the technical field of wind load test methods, and discloses a high-uniformity wind speed blowing device and an indoor blowing test method. The wind speed uniformity of a fan outlet is improved through a partitioned rectification structure, so as to integrally form a high-uniformity flow field module array. The wind speed of a constant-frequency fan with a variable-installation-angle impeller is adjusted by adjusting the installation angle of the fan blade, the construction cost of a variable-speed blowing system is reduced, the simulation of a natural blowing flow field and the analysis of an indoor blowing flow field are carried out, the equivalence of indoor blowing and natural blowing is realized, the wind field follow-up control strategy based on a target motion track is established, and the wind field is accurately controlled.

Description

Technical Field

[0001] This invention relates to the field of wind load testing methods, and discloses a high uniform wind speed blowing device and an indoor blowing test method. Background Technology

[0002] Equipment and facilities used outdoors, such as aircraft, vehicles, drones, and power equipment, are inevitably subjected to various climatic environments, including high and low temperatures, rainfall, snowfall, humidity, solar radiation, and wind. Their ability to maintain function and performance under these climatic conditions is called climatic adaptability. Typically, such equipment and facilities must undergo testing to verify that their climatic adaptability meets requirements before they can be put into production or used. Wind environment testing is one type of climatic environment testing among many.

[0003] Wind tests are categorized into two types based on the wind source: The first is natural wind testing, where the equipment or device under test is placed in a natural wind field for functional and performance testing, verifying or certifying its adaptability to wind environments. The advantages of this type of test are that it does not require the construction of a wind-blowing device and provides the most realistic test results; the disadvantages are that the test location and time are limited by region and season, capturing natural winds that meet the required wind speed is extremely difficult, and the test suffers from high costs, long cycles, and insufficient verification. The second type is artificial wind testing, where the equipment or device under test is placed in an artificially simulated wind field for functional and performance testing, verifying or certifying its adaptability to wind environments. This type of test is usually conducted in a laboratory. Its advantages are that the test is not limited by season or region, wind fields that meet the required wind speed can be artificially simulated, the test cycle is short, the cost is low, and the verification is thorough; the disadvantages are that it requires the construction of a wind-blowing device that meets the required wind speed and a sufficiently large test space. Therefore, natural wind testing is no longer sufficient to verify and evaluate the adaptability of equipment and facilities used in the open air to wind environments, which is no longer sufficient to meet the rapid development needs of equipment in industries such as aviation, transportation, and power. Currently, artificial wind testing has become the main method for testing the adaptability of equipment to wind environments.

[0004] Currently, artificial wind testing mainly simulates different wind speeds by using frequency converters for fans, and achieves wind field uniformity by setting up a rectifier section at the fan outlet. This method is feasible and economical for small or stationary test objects; however, for large test objects or those with a wide range of movement, a set of technical specifications is needed that can meet the requirements of wind speed, wind speed uniformity, configuration adapted to the test object, and low construction cost for the wind device and corresponding testing technology. Summary of the Invention

[0005] The purpose of this invention is to provide a high-uniformity wind speed blowing device and an indoor blowing test method, which can realize the modularization of the fan system, achieve adjustable wind speed and high uniformity, and reduce test costs.

[0006] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows: A high-uniformity wind speed blowing device, comprising: A fan array, comprising a plurality of fan modules, each fan module comprising at least one fan, each fan comprising a housing and a variable angle impeller mounted within the housing, wherein the outlet section of the housing is provided with a zoned rectification structure; A support structure, one end of which is fixed to the wind turbine array, and the other end of which is connected to a fixed point.

[0007] Furthermore, the variable mounting angle impeller includes a hub and blades. The blade mounting area of ​​the hub is provided with a connecting spherical surface, and the root of the blade is provided with a connecting arc surface of the same diameter as the connecting spherical surface, which is used to fit against the connecting spherical surface when the blade is mounted on the hub, so that the blade can adjust the mounting angle.

[0008] Furthermore, the partitioned rectification structure includes several rectifier plates, which are used to divide the internal space of the air outlet section of the outer casing into several rectification channels.

[0009] Furthermore, the fan module also includes a frame for fixing the fan, and a shock-absorbing structure is provided between the fan and the frame.

[0010] A method for conducting indoor air blowing tests with high uniform wind speed, based on the aforementioned high uniform wind speed air blowing device, includes: Construct the relationship between the blower's air velocity and the blade installation angle; The motion test specimen was simulated under natural wind flow to obtain the wind load and wind speed that the motion test specimen experienced in a given natural wind flow field. Based on the wind speed experienced by the moving test piece in a given natural wind flow field, a laboratory wind flow field simulation is performed on the moving test piece. The target distance between the moving test piece and the blowing device is determined with the goal that the wind load experienced by the moving test piece in the indoor wind flow field is the same as the wind load experienced in the natural wind flow field. The laboratory wind flow field is formed by the blowing device. Based on the relationship between the wind speed of the fan and the blade installation angle, and according to the wind speed experienced by the moving test piece in a given natural wind flow field, the target installation angle of the blade corresponding to the wind speed experienced by the moving test piece in the given natural wind flow field is obtained. The blades of the wind turbine are adjusted according to the target installation angle of the blades in the wind turbine, and the moving test piece is placed at a position at a target distance from the blowing device. Then, the blowing device performs a follow-up blowing test on the moving test piece according to the preset follow-up control strategy.

[0011] Furthermore, the motion test piece has a rectangular structure. In the blowing test, one end of the motion test piece is hinged to a fixed point and rotates around the hinge axis.

[0012] Furthermore, the method for determining the preset servo control strategy includes: The curve of the rotation angle of the moving test piece about the hinge axis changing with time was determined by experiment; the rotation angle of the moving test piece is the central angle of the position of the moving test piece relative to the starting position of the movement after the moving test piece has moved for a preset time. The motion test specimen is projected onto the air blowing device to obtain the projection area of ​​the motion test specimen on the air blowing device. Based on the projection area of ​​the moving test piece on the blowing device at the current moment, keep the fan covered by the current projection area running and turn off the fan that has been swept by the projection area. At the same time, based on the rotation angle of the moving test piece at the current moment and the curve of the rotation angle of the moving test piece changing with time, turn on the fan that will be covered by the corresponding projection area of ​​the moving test piece after a preset time.

[0013] Furthermore, the number of fan modules and the number of fans in the blowing device are determined based on the test wind speed range, blowing area, and geometry of the moving test piece in the blowing test.

[0014] Compared with the prior art, the beneficial effects of this invention are: This invention employs multiple fan modules assembled into a fan array, which can be adjusted according to the geometry and shape of the test object to achieve comprehensive conformal wind field coverage of the test object. A zoned rectification structure improves the uniformity of airflow velocity at the fan outlet, facilitating the integration of highly uniform flow field module arrays. By using a fixed-frequency fan with a variable-angle impeller, the wind speed of the fixed-frequency fan is adjusted by changing the installation angle of the fan blades, reducing the construction cost of the variable-speed airflow system. Through simulation of natural airflow and analysis of airflow in the laboratory, the equivalence between indoor airflow and natural airflow is achieved. A wind field servo control strategy based on the target motion trajectory is established to achieve precise wind field control. Attached Figure Description

[0015] Figure 1 This is a front view of the high uniform wind speed blowing device in the embodiment; Figure 2 for Figure 1 Side view; Figure 3 This is a schematic diagram of the structure of the two fan modules in the embodiment; Figure 4 This is a schematic diagram of the fan structure in the embodiment; Figure 5 This is a schematic diagram of the partitioned rectification structure and variable installation angle impeller of the fan in the embodiment; Figure 6 This is a schematic diagram of the variable mounting angle impeller in the embodiment; Figure 7 This is a schematic diagram of the motion of the test specimen in the embodiment; Figure 8 This is a flowchart of the indoor air blowing test method with high uniform wind speed in the embodiment; Among them, 1-fan array, 2-fan module, 21-fan, 211-casing, 212-variable mounting angle impeller, 2121-hub, 2122-blade, 22-frame, 23-zone rectification structure, 231-rectifier plate, 3-support structure. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0017] Example See Figures 1 to 7 This embodiment provides a high uniform wind speed blowing device, including: A fan array 1 includes several fan modules 2; each fan module 2 includes at least one fan 21. In this embodiment, a single fan module 2 includes four fixed-frequency fans 21, which are fixed together by a frame 22. Adjacent fan modules 2 are connected by bolts or by tenon and mortise structures. Each fan 21 includes a housing 211 and a variable-angle impeller 212 installed inside the housing 211. The air outlet section of the housing 211 is provided with a zoned rectification structure. A support structure 3 is provided, with one end fixed to the fan array 1 and the other end connected to a fixed point. The fixed point can be the ground. The support structure 3 is used to balance the counter-thrust of the fan 21 and prevent the fan array 1 from tipping over.

[0018] In this embodiment, the fan array 1 is assembled from multiple fan modules 2. The fan array 1 can be adjusted according to the geometric size and shape of the test object to achieve comprehensive conformal coverage of the test object by the wind field. The uniformity of the air velocity at the outlet of the fan 21 is improved by the partitioned rectification structure 23, so as to integrate and form a highly uniform flow field module array. By using a fixed-frequency fan 21 with a variable installation angle impeller 212, the wind speed of the fixed-frequency fan 21 is adjusted by adjusting the installation angle of the fan blades 2122, which reduces the construction cost of the variable wind speed blowing system. By simulating the natural blowing flow field and analyzing the blowing flow field in the laboratory, the equivalence between indoor blowing and natural blowing is achieved. A wind field follow-up control strategy based on the target motion trajectory is established to achieve precise wind field control.

[0019] In this embodiment, the variable installation angle impeller 212 includes a hub 2121 and blades 2122. The hub 2121 has a connecting spherical surface in the blade 2122 mounting area, and the root of the blade 2122 has a connecting arc surface with the same diameter as the connecting spherical surface. When the blade 2122 is mounted on the hub 2121, the connecting arc surface at the root of the blade 2122 fits against the connecting spherical surface of the hub 2121, allowing the blade 2122 to be mounted at any installation angle. This allows for adjustment of the wind speed of the fan 21 by adjusting the installation angle of the blade 2122. Compared with the traditional method of adjusting variable wind speed using a motor frequency converter, this embodiment achieves wind speed adjustment by adjusting the installation angle of the blades 2122 on the fixed frequency fan 21, thereby reducing the construction cost of the fan array 1.

[0020] In this embodiment, the partitioned rectification structure includes several rectifier plates 23, which are used to divide the internal space of the air outlet section of the outer casing 211 into several rectification channels. In this embodiment, the rectifier plates 23 are assembled in a star-shaped structure within the outer casing 211. That is, for all rectifier plates 23, one side of each rectifier plate 23 is located on the axis of the fan 21, and the other side of each rectifier plate 23 is fixed to the outer casing 211. Furthermore, all rectifier plates 23 located on one side of the fan 21 axis can be welded together. It should be noted that those skilled in the art can adjust the number of rectifier plates 23 as needed. This embodiment adds a cross-shaped partitioned rectification structure to the air outlet section of the fan 21, dividing the internal space of the air outlet section of the fan 21 into eight equal parts. This achieves the equal division of the air volume of the fan 21 into eight equal parts, and also breaks the vortex. Compared with the scheme of rectifying at the air outlet of the fan 21, this embodiment performs partitioned rectification within the air outlet section of the fan 21, advancing the automatic uniformization of air velocity and improving the uniformity of air velocity at the air outlet of the fan 21.

[0021] In this embodiment, the fan module 2 further includes a frame 22 for fixing the fan 21. A shock-absorbing structure is provided between the fan 21 and the frame 22. The shock-absorbing structure includes a rubber block and connecting bolts. A connecting bolt is installed on each side of the rubber block. When installing the fan 21, the rubber block is placed between the fan 21 foot and the frame 22. Then, the connecting bolts are used to connect the fan 21 foot to the rubber block and the frame 22 to the rubber block, respectively.

[0022] Based on the same inventive concept, such as Figure 8 This embodiment also provides a method for conducting indoor air blowing tests with high uniform wind speed, based on the aforementioned high uniform wind speed air blowing device, including: Step 1: Based on the requirements of the air blowing test, determine the test wind speed range, blowing area, and geometry of the target blowing area for the indoor air blowing test. Based on the area of ​​the target blowing area and the area of ​​a single fan module, plan the number of fan modules 2 and fans 21 required for the test, and complete the optimization and adjustment of the fan array 1 in the air blowing device. The air blowing requirements include the given test wind speed range and blowing area, where the blowing area is equal to the sum of the blowing areas of all fan modules in operation on the fan array. The geometry of the target blowing area is determined based on the geometry of the moving test piece, and the target blowing area must fully cover the moving test piece. The target blowing area refers to the target area that meets the wind speed requirements. The size and shape of the target blowing area can be constructed using fan modules to meet different test requirements.

[0023] The motion test piece in this embodiment is a rectangular body measuring 16m x 2m. One end of the motion test piece is hinged to a fixed point at a certain height above the ground. During the test, the motion test piece rotates around the hinge axis within the range of 0° to 90°. Figure 7 As shown.

[0024] Step 2: Construct the relationship between the blower's airflow velocity and the blade installation angle. Specifically, perform finite element analysis on the blower to obtain multiple sets of airflow velocities at different blade installation angles. Then, fit and construct a curve showing the change of the blower's airflow velocity with the blade installation angle. Measure the airflow velocity of the prototype at multiple blade installation angles to correct the curve showing the change of the blower's airflow velocity with the blade installation angle.

[0025] Step 3: Simulate the natural wind flow field of the moving test specimen to obtain the wind load and wind speed that the moving test specimen experiences in a given natural wind flow field.

[0026] Step 4: Based on the wind speed experienced by the moving test piece in a given natural wind flow field, a laboratory wind flow field simulation is performed on the moving test piece. The target distance between the moving test piece and the blowing device is determined, with the goal of ensuring that the wind load experienced by the moving test piece in the indoor wind flow field is the same as that experienced in the natural wind flow field. The laboratory wind flow field is formed by the blowing device. Furthermore, the pressure and flow field distribution within the laboratory are simultaneously obtained through the laboratory wind flow field simulation to facilitate a safety assessment of other experimental facilities within the laboratory. This invention, through simulation analysis, ensures that the laboratory wind test and the natural wind test generate the same or similar wind loads, thereby guaranteeing the equivalence between laboratory wind and natural wind.

[0027] Step 5: Based on the relationship between the wind speed of the fan 21 and the blade installation angle, and according to the wind speed that the moving test piece experiences in the given natural wind flow field, obtain the target installation angle of the blade 2122 corresponding to the wind speed that the moving test piece experiences in the given natural wind flow field. Step 6: Adjust the blades 2122 of the fan 21 according to the target installation angle of the blades 2122, place the moving test piece at the target distance, and then the blowing device forms a wind field that reaches the design test wind speed according to the preset follow-up control strategy to conduct a follow-up blowing test on the moving test piece.

[0028] In this embodiment, the method for determining the preset follow-up control strategy includes: Step (1): Determine the curve of the rotation angle of the moving test piece around the hinge axis as a function of time through experiments; the rotation angle of the moving test piece is the central angle of the position of the moving test piece relative to the starting point position after the moving test piece has moved for a preset time.

[0029] Step (2): Project the motion test piece onto the blowing device to obtain the projection area of ​​the motion test piece on the blowing device.

[0030] Step (3): Based on the projection area of ​​the moving test piece on the blowing device at the current moment, keep the fan 21 covered by the current projection area running, and turn off the fan 21 that has been swept by the projection area. At the same time, based on the rotation angle of the moving test piece at the current moment and the curve of the rotation angle of the moving test piece changing with time, turn on the fan 21 that will be covered by the corresponding projection area of ​​the moving test piece after a preset time. The preset time is set as needed. In this embodiment, the preset time is set to 3s. When the test starts, the control system of the blowing device turns on the fan 21 covered by the corresponding projection area of ​​the moving test piece in the first 3s. From the 0s moment, the moving test piece starts to rotate. At the same time, based on the rotation angle of the moving test piece at the 0s moment and the curve of the rotation angle of the moving test piece changing with time, the rotation angle of the moving test piece at the 4s moment is calculated. When the moving test piece reaches the 1st second, the control system of the blowing device activates the moving test piece at a rotation angle of [value missing]. The fan 21 that will be covered by the projection area is turned on, and the fan at time 0s that the projection area has already swept is turned off. That is, when the moving test piece moves to time 1s, the control system of the blowing device turns on the fan 21 corresponding to time 4s and simultaneously turns off the fan 21 at time 0s. Thereafter, as the rotation angle of the moving test piece increases, the turning on and off of the fans on the blowing device is carried out in this manner. By adopting the preset follow-up control strategy of the present invention, it is ensured that the entire area where the moving test piece is located is in the wind field when the moving test piece rotates to each rotation angle, ensuring that the test requirements are met and energy saving is achieved at the same time.

[0031] It should be noted that during the indoor air blowing test, turning on all or part of the fans will not affect the wind speed in the target area being blown by the fans.

[0032] The blowing test method in this embodiment uses flow field simulation analysis to determine the relative position of the moving test piece and the blowing device, ensuring that the flow field of the indoor blowing test is consistent with the natural wind field in the outdoor field. This improves the accuracy of the indoor blowing test results, allowing the results of the outdoor natural wind field test to be obtained indoors. Simultaneously, flow field simulation analysis can also obtain the flow field distribution of the indoor blowing test. The safety of the test can be assessed based on the simulation results, providing a basis for pre-developing measures to avoid test risks and ensuring the safety of the blowing test.

[0033] The wind test method in this embodiment achieves the homing of the wind field and the moving test piece through a preset follow-up control strategy, which can minimize the power supply requirements and energy consumption of the wind test and reduce the test cost.

[0034] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for conducting indoor air blowing tests with high uniform wind speed, implemented using a high uniform wind speed blowing device, the high uniform wind speed blowing device comprising a fan array (1) and a support structure (3), the fan array (1) comprising a plurality of fan modules (2), the fan module (2) comprising at least one fan (21), the fan (21) comprising a housing (211) and a variable angle impeller (212) installed in the housing (211), the air outlet section of the housing (211) being provided with a zoned rectification structure; the support structure (3) One end is fixed to the wind turbine array (1), and the other end is connected to a fixed point; the variable installation angle impeller (212) includes a hub (2121) and blades (2122), the blade (2122) mounting area of ​​the hub (2121) is provided with a connecting spherical surface, and the root of the blade (2122) is provided with a connecting arc surface with the same diameter as the connecting spherical surface, for fitting with the connecting spherical surface when the blade (2122) is mounted on the hub (2121) so as to adjust the installation angle of the blade (2122); characterized in that, include: The relationship between the blowing speed of the fan (21) and the blade installation angle was constructed. The motion test specimen was simulated under natural wind flow to obtain the wind load and wind speed that the motion test specimen experienced in a given natural wind flow field. Based on the wind speed experienced by the moving test piece in a given natural wind flow field, a laboratory wind flow field simulation is performed on the moving test piece. The target distance between the moving test piece and the blowing device is determined with the goal that the wind load experienced by the moving test piece in the indoor wind flow field is the same as the wind load experienced in the natural wind flow field. The laboratory wind flow field is formed by the blowing device. Based on the relationship between the wind speed of the fan (21) and the blade installation angle, and according to the wind speed that the moving test piece experiences in the given natural wind flow field, the target installation angle of the blade (2122) corresponding to the wind speed that the moving test piece experiences in the given natural wind flow field is obtained. Adjust the blades (2122) of the fan (21) according to the target installation angle of the blades (2122) in the fan (21), and place the moving test piece at a position at a target distance from the blowing device. Then, the blowing device performs a follow-up blowing test on the moving test piece according to the preset follow-up control strategy. The methods for determining the preset follow-up control strategy include: The curve of the rotation angle of the moving test piece about the hinge axis changing with time was determined by experiment; the rotation angle of the moving test piece is the central angle of the position of the moving test piece relative to the starting position of the movement after the moving test piece has moved for a preset time. The motion test specimen is projected onto the air blowing device to obtain the projection area of ​​the motion test specimen on the air blowing device. Based on the projection area of ​​the moving test piece on the blowing device at the current moment, keep the fan (21) covered by the current projection area running, and turn off the fan (21) that has been swept by the projection area. At the same time, based on the rotation angle of the moving test piece at the current moment and the curve of the rotation angle of the moving test piece changing with time, turn on the fan (21) that will be covered by the corresponding projection area of ​​the moving test piece after a preset time.

2. The indoor air blowing test method with high uniform wind speed according to claim 1, characterized in that, The motion test piece is a rectangular structure. In the wind test, one end of the motion test piece is hinged to a fixed point and rotates around the hinge axis.

3. The indoor air blowing test method with high uniform wind speed according to claim 1, characterized in that, The number of fan modules and the number of fans in the blowing device are determined based on the test wind speed range, blowing area, and geometry of the moving test piece in the blowing test.

4. The indoor air blowing test method with high uniform wind speed according to claim 1, characterized in that, The partitioned rectification structure includes several rectifier plates (23), which are used to divide the internal space of the air outlet section of the outer casing (211) into several rectification channels.

5. The indoor air blowing test method with high uniform wind speed according to claim 1, characterized in that, The fan module (2) also includes a frame (22) for fixing the fan (21), and a shock-absorbing structure is provided between the fan (21) and the frame (22).

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