Wind tunnel test device and method for drag coefficient of steel pipe rod

Abstract

The present invention provides a wind tunnel test device and method for the resistance coefficient of a steel pipe rod, comprising: a steel frame (3) arranged in a wind tunnel, slide rails arranged at both ends of the steel frame (3), a model steel pipe rod with adjustable length, and a plurality of wind pressure measuring points; the two ends of the model steel pipe rod are connected to the slide rails; the vertical plane angle of the model steel pipe rod is adjusted by adjusting the length of the model steel pipe rod; the plurality of wind pressure measuring points are distributed on the model steel pipe rod, and are arranged at intervals of a preset angle in the circumferential direction of the model steel pipe rod, thereby realizing the wind pressure test of the steel pipe rod at any angle on the vertical plane, and providing experimental support for accurately testing the resistance coefficient of the steel pipe rod.

Description

Technical Field

[0001] The present invention relates to the field of wind tunnel testing of wind load resistance coefficient of transmission lines, and in particular to a wind tunnel testing device and method for the resistance coefficient of a steel pipe rod. Background Art

[0002] Lattice transmission towers are generally composed of angle steel members and steel pipe members. The wind loads on their segments can be calculated using the drag coefficient of the single-piece truss and the member drag coefficient, respectively. The transmission tower wind load calculation method based on the member drag coefficient is more refined. Wind tunnel testing is an important means to study the wind load resistance coefficient of transmission tower segments and members. Because angle steel is not significantly affected by the Reynolds number effect, conventional atmospheric boundary layer wind tunnels can meet the testing requirements of its drag coefficient, and wind tunnel testing methods are relatively mature. The wind load effect on steel pipe transmission towers belongs to the typical blunt body flow category, often accompanied by phenomena such as airflow separation, reattachment, and vortex shedding, and its Reynolds number effect is relatively complex.

[0003] The current wind tunnel test methods and systems for steel pipe members have three major deficiencies: First, they fail to consider the effect of the angle between the transmission tower steel pipe member and the vertical plane on the member's drag coefficient; second, due to the limitations of wind tunnel size and steel pipe member size, they cannot meet the requirement for similar Reynolds numbers; and third, the high-frequency balance force measurement method cannot effectively test the drag coefficient of large-scale steel pipe members and reflect the resistance differences in the circumferential direction. These three deficiencies result in the need to improve the accuracy of the steel pipe member drag coefficient determined by traditional wind tunnel test methods. These three deficiencies are discussed in detail below:

[0004] (1) During wind tunnel tests of steel pipe rods, the rods are placed in a horizontal or vertical plane. For transmission tower structures, since the constituent segments have a certain inclination along the height or length direction, the angle between the actual installation position of the rod and the vertical plane will affect the wind load resistance coefficient of the rod. This effect has not been considered in previous wind tunnel tests.

[0005] (2) In traditional wind tunnel test research on the tower body or crossarm of steel tube towers, due to the limitations of wind tunnel size and transmission tower structure size, the scale of the steel tube tower model is relatively large. For low-speed wind tunnels, the wind speed similarity coefficient that meets the Reynolds number similarity is generally not achievable. The model shows that surface roughening technology cannot truly eliminate the influence of Reynolds number. Therefore, many wind tunnel tests of steel tube members abandon the similarity requirement of Reynolds number, that is, the influence of Reynolds number difference on the drag coefficient of the steel tube model is not considered. At present, there is no unified conclusion on the influence of Reynolds number on the drag coefficient of steel tube members. Foreign countries generally use the curve of the change of steel tube tower drag coefficient with Reynolds number in Australia to make corrections. However, the wind tunnel test data on which this curve is based is relatively old. Due to the limitations of wind tunnel quality and test instruments at that time, its reliability is also facing challenges. Combining the existing low-speed boundary layer wind tunnel test capabilities, solving the Reynolds number similarity problem by increasing turbulence and other technical methods is the development trend of wind tunnel test technology for steel tube members.

[0006] (3) Wind tunnel tests of the resistance coefficient of steel pipe members generally use a high-frequency force balance connected at the end to measure the six-component force under the action of the flow, and then calculate the wind load resistance coefficient of the steel pipe member. Its limitation is that it is difficult to directly test the resistance of large-sized steel pipe members using a force balance with an appropriate range, and the resistance along the circumference of the steel pipe varies significantly. This difference cannot be reflected by force balance measurement. It is necessary to use a method based on multi-point wind pressure testing to obtain the resistance distribution and overall resistance coefficient of the steel pipe member. Summary of the Invention

[0007] In response to the shortcomings of the existing technology, the present application designs a wind tunnel test device and method for the drag coefficient of steel pipe rods. The method first conducts a statistical analysis of the angles between the tower body and the front and side surfaces of a typical steel pipe transmission tower and their corresponding vertical planes, determines the angle range between the steel pipe rods and the vertical plane during the wind tunnel test, and designs a wind tunnel test device for steel pipe rods that can take the angle of the vertical plane into consideration; the drag coefficient of steel pipe rods under different Reynolds numbers and turbulence intensities is tested, and the corresponding relationship between turbulence intensity and Reynolds number and the resonance range in which they are located is proposed; wind pressure measurement points are evenly arranged along the circumference of the steel pipe at angular intervals, and a calculation method for obtaining the drag coefficient of steel pipe rods using the wind tunnel test pressure measurement method is proposed; finally, a wind tunnel test method and system for the drag coefficient of steel pipe rods that effectively considers the influence of the above three factors are proposed, providing a reference and basis for more accurate testing of the drag coefficient of steel pipe rods. Compared with the traditional wind tunnel test method for the drag coefficient of steel pipe rods, the method of the present invention solves the problems of not considering the plumb plane angle of the steel pipe rods, the inability to ensure the similarity of the Reynolds numbers of large-sized steel pipes, and the inability of the balance force measurement method to accurately test the drag coefficient of large-sized angle steels and reflect the circumferential resistance distribution characteristics. It has better applicability and higher accuracy.

[0008] The purpose of the present invention is achieved through the following technical solutions:

[0009] The present invention provides a wind tunnel test device for the resistance coefficient of a steel pipe rod, comprising: a steel frame (3) arranged in a wind tunnel, slide rails arranged at both ends of the steel frame (3), a model steel pipe rod with adjustable length, and a plurality of wind pressure measurement points;

[0010] The two ends of the model steel pipe rod are connected to the slide rails; the plumb plane angle of the model steel pipe rod is adjusted by adjusting the length of the model steel pipe rod;

[0011] The plurality of wind pressure measuring points are distributed on the model steel pipe member, and are arranged at intervals of a preset angle in the circumferential direction of the model steel pipe member.

[0012] Preferably, it further comprises a nut;

[0013] Both ends of the model steel pipe rod are rotatably connected to the slide rail through nuts.

[0014] Based on the same design concept, the present invention also provides a wind tunnel test method for the drag coefficient of a steel pipe member, comprising:

[0015] Based on the angle between the steel pipe member to be tested and the plumb plane, adjusting the angle between the model steel pipe member and the plumb plane in the wind tunnel test experimental device according to any one of claims 1 to 2;

[0016] The wind pressure of the model steel pipe member is collected based on multiple wind pressure measuring points in the wind tunnel test experimental device;

[0017] Calculating the resistance coefficient of the model steel pipe member according to the wind pressure;

[0018] The resistance coefficient of the steel pipe member to be measured is calculated based on the resistance coefficient of the model steel pipe member.

[0019] Preferably, the angle between the steel pipe member to be tested and the vertical plane is set on the wind tunnel test experimental device, and the angle between the model steel pipe member set for the steel pipe member to be tested and the vertical plane includes:

[0020] Statistical analysis of the geometric parameters of the front and side surfaces of the transmission tower segment where the tested steel pipe fittings are located;

[0021] Calculating the angle between the steel pipe member under test and the vertical plane based on the statistical parameters;

[0022] According to the angle between the steel pipe member to be tested and the plumb plane, the angle between the model steel pipe member set for the steel pipe member to be tested and the plumb plane on the experimental device is adjusted.

[0023] Preferably, the calculation formula for the angle between the steel pipe member to be tested and the vertical plane is:

[0024]

[0025] Where: β is the angle between the steel pipe member under test and the vertical plane, a is the upper width of the tower segment, b is the lower width of the tower segment, and H is the height of the tower segment.

[0026] Preferably, the calculation of the resistance coefficient of the steel pipe member to be measured based on the resistance coefficient of the model steel pipe member includes:

[0027] Calculating the geometric scale ratio between the model steel pipe member and the measured steel pipe member;

[0028] Calculating the Reynolds numbers of the model steel pipe member and the measured steel pipe member according to the geometric scale ratio;

[0029] Calculate the turbulence intensity correction factor based on the Reynolds number;

[0030] The resistance coefficient of the steel pipe member under test is calculated according to the turbulence intensity correction coefficient.

[0031] Preferably, the calculation formula of the resistance coefficient of the steel pipe rod to be tested is:

[0032] C D =K T C Ds

[0033] Where: C D K is the resistance coefficient of the steel pipe member being tested, T is the turbulence intensity correction factor, C Ds is the resistance coefficient of the model steel tube member.

[0034] Preferably, the calculation formula for the resistance coefficient of the model steel pipe rod is:

[0035]

[0036] Where: C Ds is the resistance coefficient of the model steel pipe member, N is the number of wind pressure measurement points on the steel pipe; C Pi is the wind pressure coefficient of the i-th measuring point; α i is the angle between the i-th measuring point and the wind axis.

[0037] Preferably, the calculation formula of the turbulence intensity correction coefficient is:

[0038]

[0039] Where: K T is the turbulence intensity correction factor; I t is the turbulence intensity of the wind tunnel inflow, I t The value of is determined by the Reynolds number.

[0040] Preferably, the calculation formula for the Reynolds number of the model steel pipe rod and the measured steel pipe rod is:

[0041] R e =VD / sν

[0042] Where: R e is the Reynolds number of the model steel pipe member and the tested steel pipe member, V is the incoming wind speed of the wind tunnel test; D is the diameter of the tested steel pipe member; s is the geometric scale ratio of the model steel pipe member and the tested steel pipe member; ν is the air viscosity

[0043] Compared with the closest prior art, the present invention has the following beneficial effects:

[0044] 1. The present invention provides a wind tunnel test device for the drag coefficient of a steel pipe rod, comprising: a steel frame (3) arranged in a wind tunnel, slide rails arranged at both ends of the steel frame (3), a model steel pipe rod with adjustable length, and a plurality of wind pressure measuring points; both ends of the model steel pipe rod are connected to the slide rails; the vertical plane angle of the model steel pipe rod is adjusted by adjusting the length of the model steel pipe rod; the plurality of wind pressure measuring points are distributed on the model steel pipe rod, and are arranged at intervals of a preset angle in the circumferential direction of the model steel pipe rod, thereby realizing the wind pressure test of the steel pipe rod at any angle on the vertical plane, and providing experimental support for accurately testing the drag coefficient of the steel pipe rod;

[0045] 2. The present invention provides a wind tunnel test method for the drag coefficient of a steel pipe rod, comprising: setting an angle between a model steel pipe rod for the steel pipe rod to be tested and the plumb plane on a wind tunnel test experimental device based on the angle between the steel pipe rod to be tested and the plumb plane; collecting wind pressure at multiple measuring points of the experimental model steel pipe rod at the angle; calculating the drag coefficient of the model steel pipe rod according to the wind pressure; calculating the drag coefficient of the steel pipe rod to be tested according to the drag coefficient of the model steel pipe rod; compared with the traditional wind tunnel test method for the drag coefficient of steel pipe rod, the method realizes accurate testing of the drag coefficient of the steel pipe rod based on the plumb plane of the steel pipe rod at any angle, ensures the similarity of the Reynolds numbers of large-size steel pipes, can accurately test the drag coefficient of large-size angle steels and reflect the circumferential resistance distribution characteristics, and has better applicability and higher precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 : Schematic diagram of the angle β between the front face of the steel tube transmission tower and the vertical plane;

[0048] Figure 2: Schematic diagram of the vertical plane angle adjustment device for steel pipe member wind tunnel test;

[0049] Figure 3 : Arrangement of pressure measurement points for wind tunnel test of steel pipe members;

[0050] Figure 4 :Measuring point wind pressure C Pi Angle α between the measuring point and the wind axis i The change curve of

[0051] Figure 5 : Flowchart of a wind tunnel test method for the drag coefficient of a steel tubular member.

[0052] Reference numerals:

[0053] a-width of the upper opening of the tower segment, b-width of the lower opening of the tower segment, H-height of the tower segment, β-angle between the steel tube member and the vertical plane, 1-wind tunnel wall, 2-nut, 3-steel frame, 4-incoming flow direction, 5-model steel tube member, 6-slide rail, 7-wind pressure measuring point, 8-cross section of the steel tube member; 9-angle between the i-th measuring point and the wind axis. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0055] Example 1

[0056] A wind tunnel test device for the drag coefficient of steel pipe rods, such as Figure 2 As shown, it includes: a steel frame 3 arranged in the wind tunnel wall 1, slide rails 6 arranged at both ends of the steel frame 3, a model steel pipe rod 5 with adjustable length and a plurality of wind pressure measuring points 7; the two ends of the model steel pipe rod 5 are connected to the slide rails 6; the plumb plane angle of the model steel pipe rod 5 is adjusted by adjusting the length of the model steel pipe rod 5; the wind pressure measuring point is used to measure the wind pressure brought by the incoming flow direction 4, and the multiple wind pressure measuring points are distributed on the model steel pipe rod, and are arranged at intervals of a preset angle in the circumferential direction of the model steel pipe rod.

[0057] A connection device is designed that can adjust the angle β between the steel pipe rod and the plumb plane. The device consists of a steel frame, a movable slide rail and a nut. The two ends of the steel pipe rod are respectively connected to the movable slide rails at the upper and lower ends of the steel frame. By adjusting the horizontal position of the end of the steel pipe rod on the slide rail, the position of the end of the steel pipe rod on the slide rail can be adjusted to obtain any plumb plane angle β.

[0058] When conducting wind tunnel tests on the drag coefficient of steel tube members, the vertical plane angle β of the steel tube members should cover the statistical value range determined according to the tower body and cross arm segments of the actual steel tube transmission tower, and the interval of the vertical plane angle β is 1°.

[0059] A wind pressure measuring point is arranged at every angle α along the circumferential direction in the middle section of the model steel pipe rod. A total of N wind pressure measuring points are arranged in the entire cross section 8 of the steel pipe rod. The arrangement method is as follows: Figure 3 shown.

[0060] Example 2

[0061] A wind tunnel test method for the drag coefficient of steel pipe members, such as Figure 5 As shown, including:

[0062] Step 1: Adjust the angle between the model steel pipe member and the plumb plane in the wind tunnel test apparatus;

[0063] Step 2: collecting the wind pressure of the model steel pipe member based on multiple wind pressure measurement points in the wind tunnel test experimental device;

[0064] Step 3: Calculating the resistance coefficient of the model steel pipe member according to the wind pressure;

[0065] Step 4: Calculate the resistance coefficient of the steel pipe rod to be tested based on the resistance coefficient of the model steel pipe rod. Specifically, the method provided by the present invention includes statistically analyzing the angles between the tower body and the front and side surfaces of a typical transmission tower and their corresponding vertical planes, determining the angle range between the steel pipe rod and the vertical plane during the wind tunnel test, and designing a steel pipe rod wind tunnel test device that can take into account the angle of the vertical plane; testing the resistance coefficient of the steel pipe rod under different Reynolds numbers and turbulence intensities, proposing the corresponding relationship between the turbulence intensity and the Reynolds number and the resonance range, and the turbulence intensity correction coefficient; evenly arranging wind pressure measurement points along the circumference of the steel pipe at angular intervals, and proposing a calculation method for obtaining the steel pipe resistance coefficient using the wind tunnel test pressure measurement method; finally, proposing a wind tunnel test method and system for the resistance coefficient of steel pipe rods that effectively considers the influence of the above three factors.

[0066] Step a: Determine the angle range between the steel tube member and the vertical plane during the wind tunnel test, and design a connection device that can adjust the angle β between the steel tube member and the vertical plane.

[0067] Based on the statistics of the geometric parameters of the front and side faces of the typical steel tube transmission tower segments, the angle β between the front face of the transmission tower and the plumb plane was calculated according to formula (a), as follows: Figure 1 As shown in the figure, the statistical calculation method of the cross arm segment angle is the same as that of the tower segment. The calculation formula of the vertical plane angle β of the steel tube member is:

[0068]

[0069] Where: a is the upper width of the tower segment (m), b is the lower width of the tower segment (m), and H is the height of the tower segment (m).

[0070] A connection device is designed that can adjust the angle β between the steel pipe rod and the plumb plane. The device consists of a steel frame, a movable slide rail and a nut. The two ends of the steel pipe rod are respectively connected to the movable slide rails at the upper and lower ends of the steel frame. By adjusting the horizontal position of the end of the steel pipe rod on the slide rail, the position of the end of the steel pipe rod on the slide rail can be adjusted to obtain any plumb plane angle β.

[0071] When conducting wind tunnel tests on the drag coefficient of steel tube members, the vertical plane angle β of the steel tube members should cover the statistical value range determined according to the tower body and cross arm segments of the actual steel tube transmission tower, and the interval of the vertical plane angle β is 1°.

[0072] Step b: Propose the corresponding relationship between turbulence intensity, Reynolds number and resonance range, as well as the turbulence intensity correction coefficient.

[0073] Combined with the wind tunnel size and the prototype size of the steel pipe member, the geometric scale ratio s of the steel pipe member wind tunnel test model is determined. When s = 1, the model steel pipe member is consistent with the prototype steel pipe member. According to formula (b), the Reynolds number R of the model steel pipe and the prototype steel pipe can be calculated. e .

[0074] R e =VD / sν (b)

[0075] Where: V is the incoming wind speed of the wind tunnel test (m / s); ν is the air viscosity, which is 1.45×10 -5 m 2 / s; D is the diameter of the steel pipe rod (m).

[0076] According to the statistical value of the Reynolds number of the transmission tower steel pipe rod, its resonance range can be divided into three ranges: subcritical region, critical region and supercritical region. The Reynolds number of the model steel pipe rod is generally located in the subcritical region. If the Reynolds number of the prototype steel pipe rod is also in the subcritical region, the resistance coefficient of the model steel pipe rod does not need to be corrected; if the Reynolds number of the prototype steel pipe rod is in the critical and supercritical regions, the turbulence intensity correction coefficient K calculated by formula (c) is T The resistance coefficient of the prototype steel tube member is corrected.

[0077]

[0078] Where: K T is the turbulence intensity correction factor (when the model geometry scale is s=1, K T =1); I t is the turbulence intensity of the wind tunnel inflow. When the Reynolds number of the prototype steel tube member is in the critical region and the supercritical region, I t Take 0.05 and 0.15 respectively.

[0079] Step c: Propose a calculation method for obtaining the resistance coefficient of the model steel pipe member based on the wind pressure test results under uniform incoming flow.

[0080] A wind pressure measuring point is arranged at every angle α along the circumference of the middle section of the model steel pipe rod. A total of N wind pressure measuring points are arranged along the entire section. The wind tunnel test device in step a is used to adjust the vertical plane angle β. The wind pressure at N measuring points under the specific vertical plane angle β is measured. At this time, the incoming flow is uniform. The resistance coefficient C of the model steel pipe rod is obtained using the pressure accumulation method. Ds , the resistance coefficient C of the model steel tube member Ds The calculation formula is:

[0081]

[0082] Where: C Ds is the resistance coefficient of the model steel pipe member, N is the number of wind pressure measurement points on the steel pipe (N = 360 / α); C Pi is the wind pressure coefficient of the i-th measuring point; α i is the angle between the i-th measuring point and the wind axis, and the axial direction of the pressure measuring piece is consistent with the tangent direction of the arc at its location.

[0083] Step d: Propose a calculation method for the drag coefficient of prototype steel tube members based on wind tunnel tests.

[0084] According to steps a and b, when the Reynolds number of the tested steel pipe member in step c is consistent with that of the prototype (s=1), the resistance coefficient C of the model steel pipe member measured in step c is Ds The resistance coefficient C of the prototype steel tube member D When the scale ratio of the tested steel pipe rod in step c is large and the Reynolds number effect is inconsistent with the prototype, the correction coefficient K between the Reynolds number of the steel pipe rod and the turbulence intensity determined in step b is T After correction, the resistance coefficient C of the prototype steel tube member D The calculation formula is:

[0085] C D =K T C Ds (e)

[0086] Where: C D is the resistance coefficient of the prototype steel tube member, K T is the correction factor between the Reynolds number of the steel tube member and the turbulence intensity.

[0087] Compared with the traditional wind tunnel test method for the drag coefficient of steel pipe members, it solves the problems of not considering the angle between the plumb plane of the steel pipe members, the inability to ensure the similarity of the Reynolds numbers of large-sized steel pipes, and the inability of the balance force measurement method to accurately test the drag coefficient of large-sized angle steels and reflect the circumferential resistance distribution characteristics. It has better applicability and higher accuracy.

[0088] Example 3

[0089] The process of conducting wind tunnel tests on the drag coefficient of steel pipe members using the above method is now introduced using a specific example.

[0090] Taking a 1000kV transmission line steel pipe transmission tower as an example, the main steel pipe specification of the tower body is Φ1016×20, the prototype steel pipe rod height is 1.0m, and the test incoming wind speed V=30m / s.

[0091] First, the angle range between the steel tube members and the vertical plane during the wind tunnel test was determined according to the method in step a. The connection device was designed to take into account the angle β between the steel tube members and the vertical plane. Based on the statistical geometric parameters of the front and side surfaces of typical steel tube transmission tower segments, the angle β between the tower body and the front of the crossarm and the vertical plane was calculated according to formula (a). The calculated range of β was 1° to 15°. For a particular tower segment with an upper width a = 15.84m, a lower width b = 17.22m, and a segment height H = 6m, β = arctan[(ba) / 2H] = arctan[(17.22-15.84) / 2 / 6] = 6.56°.

[0092] A connection device was designed to adjust the angle β between a steel tube member and the vertical plane. The device consists of a steel frame, movable slides, and nuts. The ends of the steel tube member are connected to the movable slides at the upper and lower ends of the steel frame. By adjusting the horizontal position of the steel tube member end on the slides, any desired angle β can be achieved. During wind tunnel tests of the steel tube member's drag coefficient, the angle β varied from 1° to 15°, with intervals of 1°.

[0093] According to the method in step b, the geometric scale ratio s=20 of the steel tube member wind tunnel test model is determined by combining the wind tunnel size and the prototype size of the steel tube member. The Reynolds numbers of the model steel tube member and the prototype steel tube member are calculated according to formula (b) as R e =VD / 20ν=1.051×10 5 and R e =VD / ν=2.102×10 6 The Reynolds numbers of the prototype steel tube member and the model steel tube member are in the subcritical region and critical region respectively, and the turbulence intensity of the wind tunnel flow I t =0.05, the turbulence intensity correction factor K calculated using formula (c) T Modify the resistance coefficient of the prototype steel tube member.

[0094] Using the method in step c, a wind pressure measuring point is arranged at every angle α = 3° along the circumferential direction of the middle section of the model steel pipe rod. A total of N = 360 / 3 = 120 wind pressure measuring points are arranged in the entire section. The wind tunnel test device in step a is used to adjust the vertical plane angle β, and the wind pressure at 120 measuring points is tested at a specific vertical plane angle β = 5°. The wind pressure at the measuring point C Pi Angle α between the measuring point and the wind axis i The change curve of Figure 4 As shown, the resistance coefficient of the steel pipe member is calculated by using the pressure accumulation method according to formula (d).

[0095] Using the method in step d, the turbulence intensity correction factor K determined in step b is T =0.82, the resistance coefficient C of the model steel pipe member measured according to step c Ds =1.12, calculate the resistance coefficient C of the prototype steel tube member according to formula (e) D =K T C Ds =0.82×0.72=0.59.

[0096] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0097] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0098] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0099] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0100] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0102] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of the pending claims.

Claims

1. A wind tunnel test method for the drag coefficient of a steel pipe member, characterized in that: include: Based on the angle between the steel pipe member to be tested and the plumb plane, the angle between the model steel pipe member and the plumb plane is adjusted on the wind tunnel test experimental device; The wind pressure of the model steel pipe member is collected based on multiple wind pressure measuring points in the wind tunnel test experimental device; Calculating the resistance coefficient of the model steel pipe member according to the wind pressure; Calculating the resistance coefficient of the steel pipe member to be tested according to the resistance coefficient of the model steel pipe member specifically includes: Calculating the geometric scale ratio between the model steel pipe member and the measured steel pipe member; Calculating the Reynolds numbers of the model steel pipe member and the measured steel pipe member according to the geometric scale ratio; Calculate the turbulence intensity correction factor based on the Reynolds number; Calculating the resistance coefficient of the steel pipe member under test according to the turbulence intensity correction coefficient; The wind tunnel test experimental device comprises: a steel frame (3) arranged in the wind tunnel, slide rails arranged at both ends of the steel frame (3), a model steel pipe rod with adjustable length, and a plurality of wind pressure measuring points; The two ends of the model steel pipe rod are connected to the slide rails; the plumb plane angle of the model steel pipe rod is adjusted by adjusting the length of the model steel pipe rod; The plurality of wind pressure measuring points are distributed on the model steel pipe member, and are arranged at intervals of a preset angle in the circumferential direction of the model steel pipe member.

2. A wind tunnel test method for the drag coefficient of a steel pipe member according to claim 1, characterized in that: The method of setting the angle between the model steel pipe member and the vertical plane for the steel pipe member to be tested on the wind tunnel test experimental device based on the angle between the steel pipe member to be tested and the vertical plane includes: Statistical analysis of the geometric parameters of the front and side surfaces of the transmission tower segment where the tested steel pipe fittings are located; Calculating the angle between the steel pipe member under test and the vertical plane based on the statistical parameters; According to the angle between the steel pipe member to be tested and the plumb plane, the angle between the model steel pipe member set for the steel pipe member to be tested and the plumb plane on the experimental device is adjusted.

3. The wind tunnel test method for the drag coefficient of a steel pipe member according to claim 2, characterized in that: The calculation formula for the angle between the steel pipe member to be tested and the vertical plane is: Where: β is the angle between the steel pipe member under test and the vertical plane, a is the upper width of the tower segment, b is the lower width of the tower segment, and H is the height of the tower segment.

4. The wind tunnel test method for the drag coefficient of a steel pipe member according to claim 1, characterized in that: The calculation formula of the resistance coefficient of the steel pipe rod under test is: C D =K T C Ds Where: C D K is the resistance coefficient of the steel pipe member being tested, T is the turbulence intensity correction factor, C Ds is the resistance coefficient of the model steel tube member.

5. A wind tunnel test method for the drag coefficient of a steel pipe member according to claim 4, characterized in that: The calculation formula of the resistance coefficient of the model steel pipe member is: Where: C Ds is the resistance coefficient of the model steel pipe member, N is the number of wind pressure measurement points on the steel pipe; C Pi is the wind pressure coefficient of the i-th measuring point; α i is the angle between the i-th measuring point and the wind axis.

6. A wind tunnel test method for the drag coefficient of a steel pipe member according to claim 4, characterized in that: The calculation formula of the turbulence intensity correction coefficient is: Where: K T is the turbulence intensity correction factor; I t is the turbulence intensity of the wind tunnel inflow, I t The value of is determined by the Reynolds number.

7. The wind tunnel test method for the drag coefficient of a steel pipe member according to claim 3, characterized in that: The calculation formula of the Reynolds number of the model steel pipe rod and the measured steel pipe rod is: R e =VD / sν Where: R e is the Reynolds number of the model steel pipe member and the tested steel pipe member, V is the incoming wind speed of the wind tunnel test; D is the diameter of the tested steel pipe member; s is the geometric scale ratio of the model steel pipe member and the tested steel pipe member; ν is the air viscosity.

8. The wind tunnel test method for the drag coefficient of a steel pipe member according to claim 1, characterized in that: The wind tunnel test experimental device also includes a nut; Both ends of the model steel pipe rod are rotatably connected to the slide rail through nuts.

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