A cooling tower model load applying method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-28
- Publication Date
- 2026-08-11
AI Technical Summary
[0004]本发明提供了一种冷却塔模型荷载施加方法，以解决现有技术中对于不同区域风荷载的计算及施加工作量大，结构设计前期工作难度大的问题
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Figure CN122549013A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of cooling tower design technology, and more specifically to a method for applying loads to a cooling tower model. Background Technology
[0002] Natural draft indirect air-cooled tower systems have been widely used in coal-rich but water-scarce thermal power plants due to their significant water-saving advantages. Steel structure cooling towers, with their high strength, lightweight design, fast construction speed, good seismic performance, and low construction costs, are becoming increasingly widely used.
[0003] Despite the numerous advantages of hyperbolic steel cooling towers, several significant challenges remain in their structural design. In the pre-design phase, software load application is typically employed. Taking wind load calculation as an example, according to relevant load specifications, loads need to be calculated and applied in separate zones: first, a zone model is established; then, wind tunnel simulation is performed on the model; subsequently, formula fitting is performed using the simulation results; finally, the concentrated loads for each zone are obtained. However, when calculating multiple zones, the above steps must be repeated multiple times to obtain the concentrated loads for each zone, resulting in a large workload and significant difficulties in the early stages of structural design. Summary of the Invention
[0004] This invention provides a method for applying loads to a cooling tower model, which solves the problems of large workload in calculating and applying wind loads in different regions and high difficulty in the early stage of structural design in the prior art.
[0005] This invention provides a method for applying loads to a cooling tower model, comprising the following steps: Step S1: Determine the panel units of the enclosure structure, wherein multiple panel units are provided; Step S2: Using the bottom center of the cooling tower model as the reference origin, establish an XYZ three-dimensional coordinate system to obtain the vertex coordinates of each plate unit in the cooling tower model; Step S3: Determine the area centroid coordinates of each plate unit in the cooling tower model based on the vertex coordinates of the plate unit; Step S4: Based on the area centroid coordinates of the plate unit, determine the projection quadrant of the area centroid of each plate unit on the XY plane, and obtain the plane angle between each plate unit and the direct blowing direction. Step S5: Based on the area centroid coordinates of each plate unit and the plane angle between each plate unit and the direct wind direction, calculate the standard value of the wind load for each plate unit. Step S6: Adjacent plate units are combined to form a load-bearing unit, and the standard value of the unit wind load on the surface of the multiple plate units is converted into the nodal concentrated load of the load-bearing unit. Step S7: Calculate the concentrated loads at the nodes of all stressed elements, apply the calculated concentrated loads at the nodes of all stressed elements to the calculation model, and complete the generation of the cooling tower model.
[0006] Beneficial effects: This method modularizes the building envelope and uses a combination of vertex coordinates of plate elements and spatial vector methods to quickly calculate the standard wind load value of each plate element through vertex coordinates. By combining different plate elements, the standard wind load value of the plate element is directly converted into the nodal concentrated load of the stress-bearing elements in different zones. This eliminates the need for repeated modeling experiments, improves design speed, and shortens the design period.
[0007] In one optional implementation, the plane angle between the plate unit and the direct airflow condition is θ. In step S4, the method for obtaining the plane angle between each plate unit and the direct airflow condition is as follows: When the centroid of the area is projected into the first quadrant. = ; When the area centroid is projected into the second quadrant. = ; When the centroid of the area is projected into the third quadrant = ; When the centroid of the area is projected into the third quadrant = ; when When θ = 0, θ is 90°; in, The x-axis coordinate of the centroid of the area. The Y-axis coordinate is the coordinate of the centroid of the area.
[0008] Beneficial effects: By determining the quadrant of the area centroid projection of the plate unit and combining it with the arctangent formula to calculate the wind direction angle in segments, the solution can be automatically solved in a programmed manner, with high accuracy and high reliability in angle calculation.
[0009] In one optional implementation, step S5 specifically includes: Step S51: Determine the wind pressure height variation coefficient based on the area centroid coordinates of each plate unit; Step S52: Determine the average wind pressure distribution coefficient based on the plane angle between each plate unit and the direct wind direction. Step S53: Calculate the standard value of wind load for each plate unit based on the wind pressure height variation coefficient and the average wind pressure distribution coefficient.
[0010] Beneficial effects: The wind pressure height variation coefficient and average wind pressure distribution coefficient can be obtained solely from the area centroid coordinates of the plate element, realizing the integration of key wind load parameters. This eliminates the need for additional complex parameter input or zonal testing, simplifies the calculation process, and significantly improves the efficiency and convenience of wind load calculation.
[0011] In one alternative implementation, the standard value of the wind load is... In step S53, the method for obtaining the standard value of the wind load for each plate unit is as follows: ; in, For wind gust coefficient, Inter-tower interference coefficient, This is the basic wind pressure; The average wind pressure distribution coefficient; This is the wind pressure height variation coefficient.
[0012] In an optional implementation, in step S51, the method for determining the wind pressure height variation coefficient is: ; in, The Z-axis coordinate is the coordinate of the centroid of the area.
[0013] In an optional implementation, in step S52, the method for determining the average wind pressure distribution coefficient is: = ; Where θ is the plane angle between the plate element and the direct-blowing airflow condition. is a coefficient.
[0014] Beneficial effects: The circumferential wind pressure distribution is expressed in the form of a cosine series, which fits the nonlinear change of the circumferential wind pressure of the cooling tower, and can be adapted to different tower types by adjusting different coefficients.
[0015] In an optional implementation, step S6, converting the standard values of the element wind loads on the surfaces of the plurality of plate elements into the nodal concentrated loads of the stressed elements, includes the following steps: By sequentially connecting the centroids of the areas of multiple plate units to the midpoints of their adjacent sides, each plate unit is projected onto the XY plane to form a polygon. The area of each polygon is obtained by using the vertex coordinates and area centroid coordinates of the plate element; The concentrated loads at the nodes of a stressed element can be obtained using the following expressions: ; Among them, Q NiHere, m represents the concentrated load at the nodes of the load-bearing element, and m is the number of plate elements that make up the load-bearing element. i The area of the polygon obtained within each plate unit. Standard wind load values for each plate unit.
[0016] Beneficial effects: By connecting the centroid of the area with the midpoint of the edge to form a polygon, the wind load is distributed according to the area ratio. The load equivalent conversion accuracy is high and the distribution is uniform. It is consistent with the actual force transmission path of the purlin structure and the nodal load application is more reasonable.
[0017] In one alternative implementation, the polygons obtained by projecting each plate unit onto the XY plane are triangles and / or quadrilaterals.
[0018] In an optional implementation, the plate unit has multiple vertices, and in step S3, the method for determining the area centroid coordinates of each plate unit in the cooling tower model is to take the arithmetic mean of the three-dimensional coordinates of all vertices of each plate unit.
[0019] In one optional embodiment, the cooling tower model includes a purlin structure and an enclosure structure, wherein the laying direction of the enclosure structure is perpendicular to the extension direction of the purlin structure, and in step S1, the plate units of the enclosure structure are determined according to the actual span and spacing of the purlin structure.
[0020] Beneficial effects: The size of the plate unit is determined based on the actual span and spacing of the purlins, the plate unit division matches the actual structure construction, the load application position is accurate, and it is more in line with the stress characteristics of steel structure cooling towers. Attached Figure Description
[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0022] Figure 1 This is a schematic diagram of the workflow of the cooling tower model load application method in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the cooling tower model according to Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the plate unit in the XYZ three-dimensional coordinate system of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the area centroid projection of the plate unit in Embodiment 1 of the present invention in the first quadrant of the XY plane; Figure 5 This is a schematic diagram of the area centroid projection of the plate unit in Embodiment 1 of the present invention in the second quadrant of the XY plane; Figure 6 This is a schematic diagram of the area centroid projection of the plate unit in Embodiment 1 of the present invention in the third quadrant of the XY plane; Figure 7 This is a schematic diagram of the area centroid projection of the plate unit in Embodiment 1 of the present invention in the fourth quadrant of the XY plane; Figure 8 This is a schematic diagram of a force-bearing unit composed of four plate units in Embodiment 1 of the present invention; Figure 9 This is a schematic diagram of the force-bearing unit in Embodiment 1 of the present invention projected onto the XY plane; Figure 10 This is a schematic diagram of the force-bearing unit composed of eight plate units in Embodiment 2 of the present invention; Figure 11 This is a schematic diagram of the force-bearing unit in Embodiment 2 of the present invention projected onto the XY plane; Figure 12 This is a schematic diagram of a force-bearing unit composed of four plate units in Embodiment 3 of the present invention; Figure 13 This is a schematic diagram of the force-bearing unit in Embodiment 3 of the present invention projected onto the XY plane.
[0023] Explanation of reference numerals in the attached figures: 10. Cooling tower model; 11. Purlin structure; 12. Enclosure structure; 121. Plate unit. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0026] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0027] The following is combined Figures 1 to 13 The following describes embodiments of the present invention.
[0028] Example 1 In this embodiment, a method for applying loads to a cooling tower model is provided, referring to... Figure 1 As shown, the steps include: Step S1: Determine the plate units 121 of the enclosure structure 12. Multiple plate units 121 are provided. Step S2: Using the bottom center of the cooling tower model 10 as the reference origin, establish an XYZ three-dimensional coordinate system to obtain the vertex coordinates of each plate unit 121 in the cooling tower model 10. Step S3: Determine the area centroid coordinates of each plate unit 121 in the cooling tower model 10 based on the vertex coordinates of the plate unit 121. Step S4: Based on the area centroid coordinates of plate unit 121, determine the projection quadrant of the area centroid of each plate unit 121 on the XY plane, and obtain the plane angle between each plate unit 121 and the direct blowing direction. Step S5: Based on the area centroid coordinates of each plate unit 121 and the plane angle between each plate unit 121 and the direct wind direction, calculate the standard value of the wind load for each plate unit 121. Step S6: Multiple adjacent plate elements 121 are combined to form a load-bearing element, and the standard value of the unit wind load on the surface of the multiple plate elements 121 is converted into the nodal concentrated load of the load-bearing element. Step S7: Calculate the concentrated loads at the nodes of all stressed elements, apply the calculated concentrated loads at the nodes of all stressed elements to the calculation model, and complete the generation of cooling tower model 10.
[0029] By applying the cooling tower model load application method of this embodiment, the enclosure structure 12 is unitized. By combining the vertex coordinates of the plate element 121 with the spatial vector method, the standard value of wind load of each plate element 121 is quickly calculated through the vertex coordinates of the plate element 121. By combining different plate elements 121, the standard value of wind load of the plate element 121 is directly converted into the nodal concentrated load of the stress unit in different zones. There is no need to repeat modeling experiments, which improves the design speed and shortens the design period.
[0030] Specifically, in this embodiment, referring to Figure 2 As shown, the cooling tower model 10 includes a purlin structure 11 and an enclosure structure 12. The laying direction of the enclosure structure 12 is perpendicular to the extension direction of the purlin structure 11. In step S1, the plate unit 121 of the enclosure structure 12 is determined according to the actual span and spacing of the purlin structure 11.
[0031] Specifically, in this embodiment, the plate unit 121 is provided in multiple layers, with multiple units in each layer. To facilitate the differentiation of the plate unit 121, the plate unit 121 of the enclosure structure 12 is named P. ij , where i corresponds to the i-th layer of plate unit 121, and j corresponds to the j-th block of plate unit 121 in the clockwise direction along the central axis of cooling tower model 10.
[0032] It is worth noting that the dimensions of plate unit 121 are determined based on the actual span and spacing of the purlins. The division of plate unit 121 matches the actual structure, and the load application position is accurate, which is more in line with the stress characteristics of steel structure cooling towers.
[0033] In this embodiment, refer to Figure 8 and Figure 9 As shown, the polygons obtained by the projection of plate element 121 onto the XY plane are all quadrilaterals.
[0034] Specifically, refer to Figure 3 As shown, the plate unit 121 has four vertices. In step S3, the method to determine the area centroid coordinates of each plate unit 121 in the cooling tower model 10 is to take the arithmetic mean of the three-dimensional coordinates of all vertices of each plate unit 121.
[0035] Specifically, taking a single plate element 121 as an example, the four vertices of the quadrilateral plate element 121 are denoted as N1(x1, y1, z1), N2(x2, y2, z2), N3(x3, y3, z3), and N4(x4, y4, z4), respectively. The coordinates of the centroid of the area of this plate element 121 are N. ij (x) ij y ij , z ij ), where x ij = (x1 + x2 + x3 + x4) / 4, y ij = (y1+y2+y3+y4) / 4, z ij = (z1+z2+z3+z4) / 4.
[0036] In this embodiment, the plane angle between the plate unit 121 and the direct airflow direction is θ. In step S4, the method for obtaining the plane angle between each plate unit 121 and the direct airflow direction is as follows: When the centroid of the area is projected into the first quadrant. = ; When the area centroid is projected into the second quadrant. = ; When the centroid of the area is projected into the third quadrant = ; When the centroid of the area is projected into the third quadrant = ; when When θ = 0, θ is 90°; in, The x-axis coordinate of the centroid of the area. The Y-axis coordinate is the coordinate of the centroid of the area.
[0037] It is worth noting that by determining the quadrant of the area centroid projection of plate unit 121 and combining it with the arctangent formula to calculate the wind direction angle in segments, the solution can be automatically solved in a programmed manner, with high accuracy and high reliability in angle calculation.
[0038] In this embodiment, step S5 specifically includes: Step S51: Determine the wind pressure height variation coefficient based on the area centroid coordinates of each plate unit 121; Step S52: Determine the average wind pressure distribution coefficient based on the plane angle between each plate unit 121 and the direct wind direction. Step S53: Calculate the standard value of wind load for each plate unit 121 based on the wind pressure height variation coefficient and the average wind pressure distribution coefficient.
[0039] It is worth noting that the wind pressure height variation coefficient and the average wind pressure distribution coefficient can be obtained solely from the area centroid coordinates of plate element 121, realizing the integration of key wind load parameters. This eliminates the need for additional complex parameter input or zonal testing, simplifies the calculation process, and significantly improves the efficiency and convenience of wind load calculation.
[0040] Specifically, the standard value of wind load is In step S53, the method for obtaining the standard value of wind load for each plate unit 121 is as follows: ; in, For wind gust coefficient, Inter-tower interference coefficient, This is the basic wind pressure; The average wind pressure distribution coefficient; This is the wind pressure height variation coefficient.
[0041] It should be noted that the wind gust coefficient Inter-tower interference coefficient Basic wind pressure All of these are fixed when the project is determined, and therefore can be regarded as constants and invariants; The average wind pressure distribution coefficient is related to the area described in the enclosure structure 12 of the cooling tower model 10 and the angle of the direct wind direction; This is the wind pressure height variation coefficient, which varies with the height of the cooling tower.
[0042] In this embodiment, the method for determining the wind pressure height variation coefficient in step S51 is as follows: ; in, The Z-axis coordinate is the coordinate of the centroid of the area.
[0043] Specifically, in this embodiment, the cooling tower model 10 has a ground roughness of type B, and the wind pressure height variation coefficient is only related to the height of the loaded area.
[0044] It should be noted that in other alternative implementations, other types of ground roughness can be used depending on the actual situation. For example, when the ground roughness is Class A, When the roughness is of type C, When the surface roughness is Class D, .
[0045] In this embodiment, the method for determining the average wind pressure distribution coefficient in step S52 is as follows: = ; Wherein, θ is the plane angle between plate unit 121 and the direct airflow direction. is a coefficient.
[0046] It should be noted that, Related to the enclosure structure 12 of the cooling tower model 10, in this application, the plate type of the enclosure structure 12 has been determined and can be considered as... The value is a constant, m=7.
[0047] Specifically, in this application, at locations on the outer surface of the cooling tower model 10 where there are no ribs, the plate element P... ij Average wind pressure distribution coefficient at location = + + + + + + + .
[0048] It is worth noting that the circumferential wind pressure distribution is expressed in the form of a cosine series, and the nonlinear change of the circumferential wind pressure of the cooling tower is fitted. Different tower types are adapted by adjusting different coefficients.
[0049] In this embodiment, step S6 converts the standard values of the element wind loads on the surfaces of the multiple plate elements 121 into the nodal concentrated loads of the stressed elements, including the following steps: By sequentially connecting the centroids of the areas of multiple plate elements 121 with the midpoints of their adjacent sides, a polygon is obtained on the projection of each plate element 121 onto the XY plane. The area of each polygon is obtained by using the vertex coordinates and area centroid coordinates of plate element 121. The concentrated loads at the nodes of a stressed element can be obtained using the following expressions: ; Among them, Q Ni The nodal concentrated load of the load-bearing element is m, where m is the number of plate elements 121 that make up the load-bearing element, and A is the number of plate elements 121 that make up the load-bearing element. i The area of the polygon obtained within each plate unit 121, Standard wind load values for each plate unit 121.
[0050] It is worth noting that by connecting the centroid of the area with the midpoint of the edge to form a polygon, the wind load is distributed according to the area ratio. The load equivalent conversion accuracy is high and the distribution is uniform. It is consistent with the actual force transmission path of the purlin structure 11, and the nodal load application is more reasonable.
[0051] Specifically, in this embodiment, four adjacent plate units 121 are selected to form a force-bearing unit, and the four plate units 121 are respectively P ij P i（j+1） P （i-1）j P （i-1）（j+1） The area centroid N of the four plate elements 121 is obtained respectively. ij N i（j+1） N （i-1）j and N （i-1）（j+1） Project the centroids of the four plate elements 121 onto the XY plane respectively, and refer to... Figures 4 to 7 The plane angle between each plate element 121 and the direct wind direction is calculated; the standard wind load values for the four plate elements 121 are as follows: , , , .
[0052] Specifically, by connecting the centroids of the areas of the four plate units 121 with the midpoints of their adjacent sides, four quadrilaterals can be obtained, with areas of A1, A2, A3, and A4 respectively.
[0053] Concentrated loads at the nodes of a load-bearing element consisting of four plate elements 121: Q Ni = + + + .
[0054] It should be noted that in the relevant technical schemes for determining the concentrated load of a zone, a zone model is first established; then, wind tunnel simulation is performed on the model; subsequently, formula fitting is performed using the simulation results; finally, the concentrated load of the zone is obtained. However, when calculating multiple zones, the above steps need to be repeated multiple times to obtain the concentrated load of different zones, which involves a large workload and makes the early stage of structural design very difficult.
[0055] Therefore, in the cooling tower model load application method of this embodiment, the enclosure structure 12 is unitized, and a calculation expression suitable for the concentrated load of the cooling tower model 10 is proposed. By combining the vertex coordinates of the plate element 121 with the spatial vector method, the standard value of the wind load of each plate element 121 is quickly calculated directly using the vertex coordinates of the plate element 121. By combining different plate elements 121, the standard value of the wind load of the plate element 121 is directly converted into the nodal concentrated load of the force-bearing element in different zones. There is no need to repeat the modeling experiment, which improves the design speed, shortens the design period, and facilitates the further development of subsequent design optimization work.
[0056] Specifically, in this embodiment, the basic wind pressure =0.5kN / m 2 , =1.24, wind gust coefficient =1.9, the cooling tower height is 178m, and the diameter of the cooling tower at zero meter and top is 129.097m and 87.5m respectively.
[0057] Specifically, board unit P ij The coordinates of the four nodes are (29.91, -28.28, 139), (30.73, -27.46, 139), (29.92, -28.30, 143.2), and (30.64, -27.40, 143.2), respectively. The plate element P... ij The center of mass N ij The coordinates are (30.30, -27.86, 141.10). Board unit P i（j+1） The coordinates of the four nodes are (30.73, -27.46, 139), (31.45, -26.56, 139), (30.64, -27.40, 143.2), and (31.37, -26.49, 143.2), respectively. The plate element P... i（j+1） The center of mass N i（j+1）The coordinates are (31.05, -26.98, 141.10). Board unit P （i-1）j The coordinates of the four nodes are (29.81, -28.18, 134.8), (30.63, -27.36, 134.8), (29.91, -28.28, 139), and (30.73, -27.46, 139), respectively. The plate element P... （i-1）j The center of mass N （i-1）j The coordinates are (30.27, -27.82, 136.9). Board unit P （i-1）（j+1） The coordinates of the four nodes are (30.63, -27.36, 134.8), (31.44, -26.54, 134.8), (30.73, -27.46, 139), and (31.45, -26.56, 139), respectively. The plate element P... （i-1）（j+1） The center of mass N （i-1）（j+1） The coordinates are (31.06, -26.96, 136.9).
[0058] Furthermore, the board unit P ij The plane angle θ between the operating conditions and the direct wind direction ij =42.59°, plate element P i（j+1） The plane angle θ between the operating conditions and the direct wind direction i（j+1） =40.99°, plate element P （i-1）j The plane angle θ between the operating conditions and the direct wind direction （i-1）j =42.58°, plate element P （i-1）（j+1） The plane angle θ between the operating conditions and the direct wind direction （i-1）（j+1） =40.98°.
[0059] Furthermore, the board unit P ij wind pressure distribution coefficient =-0.4426×cos(42.59°)+0.2451×cos(1×42.59°)+0.6752×cos(2×42.59°)+0.5356×cos(3×42.59°)+0.0615×cos(4×42.59°)-0.1384×cos(5×42.59°)+0.0014×cos(6×42.59°)+0.065×cos(7×42.59°)=-0.448; Similarly, the plate element P can be calculated. i（j+1） wind pressure distribution coefficient The value is -0.370, and the plate unit P is... （i-1）j wind pressure distribution coefficient The value is -0.370, and the plate unit P is... （i-1）（j+1） wind pressure distribution coefficient It is -0.370.
[0060] Furthermore, the board unit P ij Height variation coefficient = =2.21; Similarly, the plate element P can be calculated. i（j+1） Height variation coefficient The value is 2.21, and the plate unit P is... （i-1）j Height variation coefficient The value is 2.19, and the board unit P is... （i-1）（j+1） Height variation coefficient It is 2.19.
[0061] Furthermore, the board unit P ij The standard values of wind load are respectively =1.9×1.24×-0.448×2.21×0.5=-1.17kN / m 2 Similarly, the plate element P can be calculated. i（j+1） Standard value of wind load -0.964 N / m 2 Board unit P （i-1）j Standard value of wind load -1.16 N / m 2 Board unit P （i-1）（j+1） Standard value of wind load -0.954 N / m 2 .
[0062] Connecting the centroids of the four plate elements 121 to the midpoints of their adjacent sides yields four quadrilaterals, each with an area of A1 = 4.854 m². 2 A2 = 4.857m 2 A3 = 4.854m 2 A4 = 4.855m 2 .
[0063] Concentrated loads at the nodes of a load-bearing element consisting of four plate elements 121: Q Ni = + + + =-5.15kN.
[0064] After verification using relevant technical methods, the results of the concentrated load at the nodes of the stress unit are within the allowable error range.
[0065] Example 2 The difference between Example 2 and Example 1 is that: (Refer to...) Figure 10 and Figure 11As shown, in this embodiment, the polygon obtained by projecting the plate unit 121 onto the XY plane is a triangle. The triangular plate unit 121 has three vertices, and the coordinates of the centroid of the triangular plate unit 121 are N. ij (x) ij y ij , z ij ), where x ij = (x1 + x2 + x3) / 3, y ij =(y1+y2+y3) / 3,z ij = (z1+z2+z3) / 3.
[0066] Specifically, in this embodiment, referring to Figure 11 As shown, eight adjacent plate elements 121 are selected to form a force-bearing element, and the eight plate elements 121 are respectively P ij P i（j+1） P i（j+2） P i（j+3） P （i-1）j P （i-1）（j+1） P （i-1）（j+2） P （i-1）（j+3） The centroids of the eight plate elements 121 are projected onto the XY plane, and the standard values of the wind loads on the eight plate elements 121 are respectively... , , , , , , , .
[0067] Specifically, by connecting the centroids of the areas of the eight plate units 121 with the midpoints of their adjacent sides, eight quadrilaterals can be obtained, with areas of A1, A2, A3, A4, A5, A6, A7, and A8, respectively.
[0068] Concentrated loads at the nodes of a load-bearing element consisting of eight plate elements 121: Q Ni = + + + + + + .
[0069] Apart from this, there are no other differences between Example 2 and Example 1, so they will not be described in detail.
[0070] Example 3 The difference between Example 3 and Example 1 is that: (Refer to...) Figure 12 and Figure 13As shown, some of the plate elements 121 are projected onto the XY plane and the resulting polygons are triangles, while others are projected onto the XY plane and the resulting polygons are quadrilaterals.
[0071] Specifically, in this embodiment, four adjacent plate units 121 are selected to form a force-bearing unit, wherein the projections of two plate units 121 onto the XY plane are triangles, and the projections of the other two plate units 121 onto the XY plane are quadrilaterals. The four plate units 121 are respectively P ij P i（j+1） P （i-1）j P （i-1）（j+1） The standard values of wind load for the four plate units 121 are as follows: , , , .
[0072] Specifically, by connecting the centroids of the areas of the four plate units 121 with the midpoints of their adjacent sides, four quadrilaterals can be obtained, with areas of A1, A2, A3, and A4 respectively.
[0073] Concentrated loads at the nodes of a load-bearing element consisting of four plate elements 121: Q Ni = + + + .
[0074] Apart from this, there are no other differences between Example 3 and Example 1, so they will not be described in detail.
[0075] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.
Claims
1. A method of applying loads to a cooling tower model, characterized by, Including the following steps: Step S1: Determine the plate unit (121) of the enclosure structure (12), and there are multiple plate units (121); Step S2: Using the bottom center of the cooling tower model (10) as the reference origin, establish an XYZ three-dimensional coordinate system to obtain the vertex coordinates of each plate unit (121) in the cooling tower model (10); Step S3: Determine the area centroid coordinates of each plate unit (121) in the cooling tower model (10) based on the vertex coordinates of the plate unit (121); Step S4: Based on the area centroid coordinates of the plate unit (121), determine the projection quadrant of the area centroid of each plate unit (121) on the XY plane, and obtain the plane angle between each plate unit (121) and the direct blowing direction condition. Step S5: Based on the area centroid coordinates of each plate unit (121) and the plane angle between each plate unit (121) and the direct wind direction, the standard value of the wind load of each plate unit (121) is obtained. Step S6: Adjacent plate units (121) are combined to form a force-bearing unit, and the standard value of the unit wind load on the surface of the multiple plate units (121) is converted into the nodal concentrated load of the force-bearing unit. Step S7: Calculate the concentrated loads at the nodes of all stressed elements, apply the calculated concentrated loads at the nodes of all stressed elements to the calculation model, and complete the generation of the cooling tower model (10).
2. The cooling tower model load application method according to claim 1, characterized by, The plane angle between the plate unit (121) and the direct airflow condition is θ. In step S4, the method for obtaining the plane angle between each plate unit (121) and the direct airflow condition is as follows: When the centroid of the area is projected into the first quadrant. = ; When the area centroid is projected into the second quadrant. = ; When the centroid of the area is projected into the third quadrant = ; When the centroid of the area is projected into the third quadrant = ; when When θ = 0, θ is 90°; in, The x-axis coordinate of the centroid of the area. The Y-axis coordinate is the coordinate of the centroid of the area.
3. The method for applying load to a cooling tower model according to claim 1, characterized in that, Step S5 specifically includes: Step S51: Determine the wind pressure height variation coefficient based on the area centroid coordinates of each plate unit (121); Step S52: Determine the average wind pressure distribution coefficient based on the plane angle between each plate unit (121) and the direct wind direction. Step S53: Based on the wind pressure height variation coefficient and the average wind pressure distribution coefficient, the standard value of wind load for each plate unit (121) is obtained.
4. The method for applying load to a cooling tower model according to claim 3, characterized in that, The standard value of the wind load is In step S53, the method for obtaining the standard value of wind load for each of the plate units (121) is as follows: ； in, For wind gust coefficient, Inter-tower interference coefficient, This is the basic wind pressure; The average wind pressure distribution coefficient; This is the wind pressure height variation coefficient.
5. The method for applying load to a cooling tower model according to claim 4, characterized in that, In step S51, the method for determining the wind pressure height variation coefficient is as follows: ； in, The Z-axis coordinate is the coordinate of the centroid of the area.
6. The method for applying load to a cooling tower model according to claim 4, characterized in that, In step S52, the method for determining the average wind pressure distribution coefficient is as follows: = ； Where θ is the plane angle between the plate element (121) and the direct airflow condition. is a coefficient.
7. The method for applying load to a cooling tower model according to any one of claims 1-6, characterized in that, In step S6, converting the standard values of the element wind loads on the surfaces of the plurality of plate elements (121) into the nodal concentrated loads of the stressed elements includes the following steps: By sequentially connecting the centroids of the areas of multiple plate units (121) with the midpoints of their adjacent sides, each plate unit (121) is projected onto the XY plane to form a polygon. The area of each polygon is obtained by using the vertex coordinates and area centroid coordinates of the plate unit (121); The concentrated loads at the nodes of a stressed element can be obtained using the following expressions: ； Among them, Q Ni For the concentrated load at the nodes of the load-bearing element, m is the number of plate elements (121) that make up the load-bearing element, and A i The area of the polygon obtained within each plate element (121), Standard wind load values for each plate unit (121).
8. The method for applying load to a cooling tower model according to claim 7, characterized in that, The polygons obtained by the projection of each plate unit (121) onto the XY plane are triangles and / or quadrilaterals.
9. The method for applying load to a cooling tower model according to any one of claims 1-6, characterized in that, The plate unit (121) has multiple vertices. In step S3, the method for determining the area centroid coordinates of each plate unit (121) in the cooling tower model (10) is to take the arithmetic mean of the three-dimensional coordinates of all vertices of each plate unit (121).
10. The method for applying load to a cooling tower model according to claim 1, characterized in that, The cooling tower model (10) includes a purlin structure (11) and an enclosure structure (12). The laying direction of the enclosure structure (12) is perpendicular to the extension direction of the purlin structure (11). In step S1, the plate unit (121) of the enclosure structure (12) is determined according to the actual span and spacing of the purlin structure (11).