JP6823488B2 - Wind tunnel experimental equipment - Google Patents

Description

The present invention relates to a wind tunnel experimental device that models the building height and topographical undulations around a construction structure.

The characteristics of the wind (airflow properties) change due to the effects of friction on the ground surface such as buildings and trees, unevenness, and undulations of the terrain. Therefore, in the wind tunnel experiment of the construction structure, the wind flow (air flow) that simulates the characteristics of the natural wind is reproduced as the target. The airflow in the wind tunnel experiment is the average wind speed and turbulence intensity (the ratio of the standard deviation of the wind speed to the average wind speed) according to the "ground surface roughness classification" specified in the "Building Load Guideline / Explanation" of the Japan Society for Architecture. ), The scale of turbulence (the average size of the wind vortex), etc. are generally set with reference to the vertical distribution. The airflow in the wind tunnel experiment is adjusted by arranging a roughness block, a horizontal grid, a spyer, or the like on the windward side of the wind tunnel measurement unit. However, since the vertical distribution of the wind speed is determined by the roughness condition on the windward side of the construction site, the ground surface roughness classification changes depending on the wind direction. On the other hand, in a wind tunnel experiment, it takes time and cost to adjust the roughness block, horizontal grid or spyer arranged on the windward side of the wind tunnel measurement unit for each wind direction.
Therefore, in Patent Document 1, the terrain undulations are reproduced by moving a plurality of base plates arranged side by side in the mainstream direction of the air passage up and down, and the roughness material is raised from the through holes formed in the base plate. As a result, a terrain model for wind tunnel experiments that reproduces the terrain roughness is disclosed.
Further, Patent Document 2 discloses a wind tunnel experimental device capable of changing the total length of a model exposed above the floor member by moving the pedestal installed below the floor member installed inside the wind tunnel up and down. Has been done.
Further, in Patent Document 3, a large number of needle-shaped members are installed on a table for an urban model, a dot machine is provided below the table, and the dot machine is moved in the XY and Y directions. An urban model making device for a wind tunnel experiment that raises and lowers a needle-shaped member is disclosed.

Japanese Unexamined Patent Publication No. 8-240511 JP-A-2000-221103 Japanese Unexamined Patent Publication No. 9-134119

In the conventional wind cave experimental device, the terrain roughness is adjusted according to the ground surface roughness classification, but strictly speaking, the vertical distribution of the wind speed specified in the ground surface roughness classification is around the construction site. It cannot be said that the airflow accurately reproduces the roughness situation. In addition, the ground surface roughness classification is 5 levels (IV to V), but it is qualitatively defined and is selected by the designer, etc. according to the condition of the ground surface of the construction site. , Judgment may differ from person to person.
Therefore, the present invention makes it possible to obtain the wind value and wind velocity acting on the construction structure as wind information reflecting the actual situation by reproducing the height of the building and the undulations of the terrain around the construction structure in detail. An object of the present invention is to provide a wind tunnel experimental device.

In order to reproduce the height of the building and the undulations of the terrain around the construction structure in relatively detail, the present inventors raise and lower the wind model block representing the roughness shape of the ground surface based on the three-dimensional shape data. He came to invent the wind tunnel experimental device.
In order to solve the above problems, the present invention presents a measurement area in which a construction structure and a construction site where the construction structure is constructed are reproduced, a blower that blows wind toward the measurement area, and the measurement area. A wind tunnel experimental device including an upwind model block region formed between the wind tunnel and the blower. A measuring tool for measuring wind information is arranged in the measurement region, and the upwind model block region is provided. Then, a plurality of model blocks that can be raised and lowered according to three-dimensional shape data representing the roughness shape of the ground surface reproduce the building height and terrain undulations in the upwind range, and also reproduce the road or open space. Tei Te, below the wind tunnel floor level of the upwind model block area, the vertical movement motor, and the rotational movement motor is characterized that you have installed.
According to this wind tunnel experimental device, the height of the building and the undulations of the terrain around the construction structure are reproduced by raising and lowering the model block based on the three-dimensional shape data, so that the wind value acting on the construction structure is reproduced. And wind speed can be obtained as wind information that reflects the actual situation. The height of the building and the undulations of the terrain around the construction structure can be reproduced in relatively detailed and easy manner by raising and lowering the model block. The ascending / descending height of the model block is the ratio of the building height and terrain undulations, the projected area of the road or open space, etc. for each plan view of each model block in the range obtained by multiplying the upwind model block area by the scale of the model block. It is based on their three-dimensional shape height. In addition, by obtaining wind information that reflects the actual situation, it is possible to accurately estimate the wind load acting on the construction structure, and by extension, study the degree of wind influence and the wind reduction structure before construction. .. In addition, the judgment of the ground surface roughness classification differs depending on the person, and the wind tunnel airflow does not differ, so that an accurate airflow for each wind direction can be easily (automatically) created.

It is desirable that the elevating height of the model block of the wind tunnel experimental device is determined by the height of the structure having the largest ratio of the dominant projected area within the range reproduced by the model block.
According to such a wind tunnel experimental device, even when the influence range of the airflow is expanded or reduced, it can be evaluated as a consistent region.
When estimating the wind load acting on the outer peripheral surface of a construction structure, in order to faithfully simulate the actual phenomenon, fix the model block of the structure and enlarge the turntable on which the model block is installed. It is possible to measure the wind load for each wind direction by increasing the model reproduction range, but this is not realistic because a huge wind tunnel experimental device is required.
In the wind tunnel experimental device, a vertical movement motor and a rotary movement motor are installed below the wind tunnel floor level of the upwind model block region, so that the blower is fixed and corresponds to each wind direction. By swinging (changing) the angle of the model block, the wind load of each wind direction acting on the outer surface of the construction structure is estimated (measured).

According to the wind tunnel experimental device of the present invention, the wind value and the wind velocity acting on the construction structure can be obtained as wind information reflecting the actual situation by reproducing the height of the building and the undulations of the terrain around the construction structure in detail. It becomes possible.

It is a perspective view which shows the wind tunnel experimental apparatus of this embodiment. It is a perspective view which shows typically the measurement cavity. (A) is an elevational view schematically showing the model block and the driving means of the first embodiment, and (b) is a schematic view showing the details of the driving means of (a). (A) is a diagram showing an example of three-dimensional shape data, and (b) is a diagram showing an example of extracted data. (A) is a perspective view showing a reproduction state of the windward district of the measurement cave, and (b) is an explanatory view showing a method of determining the height of the model block. (A) is an elevation view schematically showing the model block and the driving means of the second embodiment, (b) is a schematic view showing the details of the driving means of (a), and (c) is a plan view of (a). Is.

The present invention is a wind tunnel experimental device for measuring (estimating) the wind load acting on the outer surface of a construction structure, and is based on three-dimensional shape data, and the buildings and terrain undulations around the construction site of the construction structure. By reproducing the above with a model block, wind information that reflects the actual situation is acquired.
In the wind tunnel experimental device of the present invention, a plurality of model blocks are provided for each wind direction without providing a gap between the blocks in the first embodiment, targeting the wind tunnel model block region located on the wind side of the construction structure. It is raised and lowered to reproduce the height of buildings, undulations of terrain, roads, and open spaces. By raising and lowering the model block for each wind direction, the building and terrain are reproduced to match the actual situation. In other words, it is formed by model blocks in which the windward model block regions are raised and lowered without gaps (FIGS. 1 to 5).
On the other hand, in the second embodiment, the windward model block region is formed by a plurality of model blocks in which gaps are provided in advance between the blocks. In detail, first, the model block is moved up and down with respect to the reference wind direction to reproduce the height of the building and the undulations of the terrain, and the angle of the model block is changed to correspond to each wind direction for each wind direction. It reproduces the height of buildings, undulations of terrain, roads, and open spaces. For example, the reference wind direction is 0 degree, 90 degree, 180 degree, 270 degree, and the angle of the model block is increased or decreased by 45 degrees with respect to the model block in the 0 degree direction. It reproduces the building height and topographical shape for each wind direction in a pseudo manner (Fig. 6).

(First Embodiment)
The first embodiment of the present invention is shown in FIG. Hereinafter, embodiments of the wind tunnel experimental device 1 according to the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, the wind tunnel experimental device 1 of the present embodiment includes a tubular main body 2 having an air supply port 21 at one end and an exhaust port 22 at the other end. Inside the main body 2, a blower 3, an upwind model block area 4, and a measurement area 5 are provided in order from one end side. The main body 2 of the present embodiment has a linear shape, and is configured to discharge the air taken in from the air supply port 21 from the exhaust port 22. The shape of the main body 2 is not limited, and for example, the main body 2 may be formed in a plan view port shape to enable air circulation. Further, the material of the main body 2 is not limited, but it may be formed by processing a metal plate, for example.
A filter is installed in the air supply port 21. This filter prevents dust, dust, etc. from entering when air is taken into the main body 2. The method of mounting the filter and the materials constituting the filter are not limited.
The exhaust port 22 is opened so that air does not stay in the main body 2. The wind tunnel experimental device 1 discharges the air blown from the air supply port 21 from the exhaust port 22 to prevent the wind from convection at the end of the main body 2 to cause turbulence. A filter or the like is installed in the exhaust port 22 as needed.
The main body 2 of the present embodiment is a so-called Eiffel-type wind tunnel in which a blower cave 23, a diffusion cave 24, a rectifying cave 25, a contraction cave 26, and a measurement cave 27 are formed in this order from the air supply port 21 side (windward side). Is. The configuration and shape of the main body 2 are not limited.

The blower cavity 23 is a cylindrical portion formed at one end of the main body 2, and the blower 3 is arranged inside. The shape of the blower cavity 23 is not limited, and may be, for example, a square cylinder having a constant cross section.
The blower 3 faces the air supply port 21, and blows the air taken in from the air supply port 21 to the exhaust port 22 side. The blower 3 is configured so that the wind force can be adjusted. The blower 3 is connected to a computer (not shown) via a control means, and the drive and the wind force are controlled by a signal from the computer. The blower 3 may be manually controlled.

The diffusion cave 24 is a portion connected to the exhaust port 22 side (leeward side) of the blower cave 23, and the inner diameter increases (inner air area increases) from the air supply port 21 toward the exhaust port 22. It is configured as follows. That is, the diffusion cave 24 is an air passage that aims to make the wind uniform by once diffusing the wind of the blower 3 in which the wind tends to be irregular (the distribution of the wind generated in the cross section, etc.).
The rectifying cavity 25 is a portion connected to the exhaust port 22 side (leeward side) of the diffusion cavity 24, and is a tubular portion having a constant inner air shape. The rectifying cavity 25 of the present embodiment has a square tubular shape, but the shape of the rectifying cavity 25 is not limited, and may be, for example, a cylindrical shape. In the rectifying cavity 25, the rectifying grid 28 and the rectifying net 29 are arranged in order from the air supply port 21 side in a direction orthogonal to the axial direction of the main body 2. The rectifying cave 25 is an air passage that regulates the flow of wind (turbulent flow) turbulent due to diffusion in the diffusing cave 24, and rectifies the wind flowing from the diffusing cave 24 by passing it through the rectifying grid 28 and the rectifying network 29 cities. To do. The number (number of sheets) of the rectifying grid 28 and the rectifying net 29 arranged in the rectifying cavity 25 is not limited and may be appropriately determined. Further, the rectifying grid 28 and the rectifying net 29 may be arranged as needed, and for example, only one of the rectifying grid 28 and the rectifying net 29 may be arranged.
The contraction cavity 26 is a portion connected to the exhaust port 22 side (leeward side) of the rectifying cavity 25, and the inner diameter is reduced from the air supply port 21 toward the exhaust port 22 (inner space cross section). Is configured to match the inner sky cross section of the measuring cave 27). The contraction cave 26 is an air passage that blows stable wind to the measurement cave 27 by the rectifying cave 25.

The measuring cave 27 is a square tubular portion formed at the other end of the main body 2, and is connected to the condensing cave 26. An exhaust port 22 is formed at the other end of the measurement cavity 27. The shape of the measurement cavity 27 is not limited, and may be, for example, a cylindrical shape.
As shown in FIG. 2, the measurement cave 27 is provided with a measurement area 5 and an upwind model block area 4.

The measurement area 5 is arranged on the exhaust port 22 side (leeward side) of the measurement cave 27. The measurement area 5 is provided with a model of the construction structure (hereinafter referred to as “structure model”) and a model of the construction site where the construction structure is constructed (hereinafter referred to as “peripheral model”). That is, in the measurement area 5, the construction structure and the structures and terrain around the construction structure are reproduced in more detail than in the windward model block area 4. Further, in the measurement area 5, a measuring tool for measuring wind information is arranged. The measuring tool uses a wind pressure sensor attached to the structure model and a wind speed sensor installed around the road or the leg of the building to measure the action of the wind blown into the measurement cave 27 on the structure model. The measuring instrument is connected to a computer (not shown). The measurement result of the measuring instrument is saved in the computer.
A turntable 51 is arranged in the measurement area 5 of the present embodiment. The structure model and the peripheral model (not shown) are provided on the turntable 51, and their orientations can be changed according to the experimental wind direction. The turntable 51 may be arranged as needed. The turntable 51 is connected to a computer (not shown) via a control means. The turntable 51 is rotated by a signal transmitted from the computer. The turntable 51 may be manually rotated.

The upwind model block region 4 is arranged on the air supply port 21 side (upwind side) of the measurement cave 27. That is, the upwind model block region 4 is formed between the blower 3 and the measurement region 5 (see FIG. 1). A plurality of model blocks 41 are aligned and arranged in the windward model block region 4. In the upwind model block area 4, as shown in FIG. 3A, the model block 41 is moved up and down according to the three-dimensional shape data to raise and lower the building height, road, and vacant lot in the upwind range of the measurement area 5. In addition to the above, the terrain undulations are reproduced. That is, the roughness shape of the windward range of the measurement area 5 is reproduced. Each model block 41 is a square in a plan view and exhibits a vertically long rectangular parallelepiped. The width and height dimensions of the model block 41 are not limited. Further, the model block 41 may be a rectangular shape in a plan view. In this embodiment, the model blocks 41 are arranged without gaps. It should be noted that a gap may be formed between the model blocks 41 so that the adjacent model block surfaces do not come into contact with each other when the model blocks 41 move up and down.

A driving means 42 is arranged below the wind tunnel floor level FL (model block 41) of the windward model block region 4 corresponding to each model block 41. As shown in FIG. 3B, the drive means 42 of the present embodiment includes a vertical movement motor 43 and a movement shaft 44, respectively. The moving shaft 44 is held so as to be vertically movable by the vertical moving motor 43. Further, the upper end of the moving shaft 44 is fixed to the lower end of the model block 41. That is, each model block 41 moves up and down in the vertical direction via the moving shaft 44 by driving the vertical movement motor 43. The moving shaft 44 of the present embodiment is composed of a ball screw and is screwed into the ball screw nut 45. The height position of the ball screw nut 45 is fixed. When the vertical movement motor 43 is driven, a rotational force is applied to the moving shaft 44. When the moving shaft 44 rotates, it moves up and down with respect to the ball screw nut 45. The material constituting the moving shaft 44 is not limited as long as it is a rod-shaped member. Further, the drive means 42 may have a hydraulic control device instead of the motor.

The configuration of the drive means 42 is not limited as long as the model block 41 can be moved up and down at least in the vertical direction. The drive means 42 is connected to a computer (not shown) via a control means. In the upwind model block area 4, the situation of the upwind district of the construction structure is reproduced by raising and lowering the model block 41 based on the three-dimensional shape data input to the computer.

Hereinafter, a measurement method using the wind tunnel experimental device 1 of the present embodiment will be described.
First, the scale A of the length of the structure model is input to the computer.
Next, the shape data (three-dimensional shape data) around the construction site of the construction structure is input. The three-dimensional shape data is data (for example, STL data) representing the position and size of a building or the like, the shape and altitude of a road or a vacant lot, terrain undulations, etc. (see FIG. 4A). As the three-dimensional shape data, publicly available or commercially available data may be used. The required minimum radius R of the shape data to be input is calculated by dividing the length L (see FIG. 2) from the center position of the turntable 51 to the windward end of the measurement area 5 by the scale A. For example, when the scale A is 1/500 and the length L is 10 m, the required minimum radius R is 10 m ÷ (1/500) = 5 km. The leeward district range is included in the circle with the minimum required radius R.

After inputting the shape data, input the definition of the experimental wind direction for the shape data and input the experimental wind direction to be measured. The wind direction with respect to the X coordinate direction or the Y coordinate direction of the shape data is defined, and the rotation direction of the turntable 51 is specified.
Next, determine the range of the windward district. The range of the windward district is determined in a direction corresponding to the experimental wind direction, and the range of the windward district is extracted according to the size of the device (width and length L of the measurement cave 27) (see FIG. 4B). The range of the windward district may be automatically extracted by the computer based on the input data of the experimental wind direction and the three-dimensional shape data.

When the range of the windward district is determined, the computer calculates the ascent and descent of the model block 41 based on the information of the three-dimensional shape data corresponding to the range, and the plurality of model blocks 41 move up and down based on the result. As a result, the windward district is simulated three-dimensionally (see FIG. 5A). That is, the roughness shape in the windward district range is reproduced. Note that FIG. 5A shows a situation in which the leeward district is simulated three-dimensionally, so that only the leeward side of the leeward district is reproduced. The shape reproduced by the model block 41 is such that the device range (the shape of the windward model block area 4) and the range obtained by multiplying the windward block area by the scale A are superimposed in the computer. To do. The height of each model block 41 is the height obtained by multiplying the height by the scale A when there is one type of height information of the three-dimensional shape data within the range reproduced by one model block 41. On the other hand, when there are a plurality of height information within the range reproduced by one model block 41, the scale A is scaled to the height of the structure, road, open space, etc., which has the largest ratio of the dominant projected area within this range. The value multiplied by is adopted as the height of the model block 41. That is, as shown in FIG. 5B, when there are three types of height information of shapes B1 to B3 in the range reproduced by the model block 41, the height of shape B2 having the largest controlling area is adopted. .. When the shape of the windward district is reproduced by raising and lowering the model block 41, the blower 3 is driven to blow air, and the state of action of the wind on the structure model is measured.

According to the wind tunnel experimental device 1 of the present embodiment, the height of the building and the undulations of the terrain around the construction structure can be reproduced relatively in detail and easily by raising and lowering the model block 41 based on the three-dimensional shape data. Can be done. In other words, the roughness shape of the upwind district area can be reproduced, and the wind value and wind velocity acting on the construction structure (structure model) can be obtained as wind information that reflects the actual situation of the upwind district area. be able to. In addition, by obtaining wind information that reflects the actual conditions of the windward district area, the wind load acting on the construction structure can be estimated accurately, and by extension, the degree of influence of the wind (building wind, etc.) and the wind before construction. It is possible to study the reduction structure of.
Further, since the height of the model block 41 is determined by the height of the structure, road, open space, etc., which has the largest ratio of the dominant projected area within the range reproduced by the model block 41, the influence range of the air flow. Can be evaluated as a consistent area even when is enlarged or reduced.

(Second Embodiment)
The second embodiment is different from the first embodiment in that the windward model block region 4 is different from the first embodiment in that a gap 6 is formed between adjacent model blocks 41 and the angle of each model block 41 with respect to the wind direction is changed. Others are the same.
FIG. 6 shows a schematic view of the model block 41 and the driving means 42 according to the second embodiment. 6 (a) and 6 (c) are schematic views of the model block 41, and FIG. 6 (b) is a schematic view of the driving means 42.
The gap 6 between the model blocks 41 has a width of 0.71 times or more the plane viewing side length of the model block 41 so as not to come into contact with other adjacent model blocks 41 when the angle of the model block 41 is changed. It is necessary to secure it. The gap 6 can be used to recreate a road or open space.
As shown in FIG. 6B, the drive means 42 includes both a vertical movement motor 43 and a rotary movement motor 46. Since the model block 41 supported by the moving shaft 44 can move up and down and rotate, it can respond to changes in the wind direction acting on the construction structure. That is, by changing the direction (angle) of each model block 41 with respect to the windward side, the wind acting on the construction structure is reproduced from all directions by using the wind tunnel experimental device 1 in which the position of the blower 3 is fixed. be able to.
If there is a gap 6 between the model blocks 41, the rotary movement motor 46 can rotate the model block 41 without moving up and down by rotating the moving shaft 44 and the ball screw nut 45. The rotation range of the rotary movement motor 46 is, for example, ± 45 ° about the axis C of the moving shaft 44, as shown in FIG. 6C. The rotation angle of the rotary movement motor 46 is not limited.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and each of the above-mentioned components can be appropriately modified without departing from the spirit of the present invention.
A ground surface plate may be provided in the upwind model block region 4. At this time, the surface of the ground surface plate shall represent the ground surface (including the road surface, etc.) at the lowest altitude of the windward district.

1 Wind tunnel experimental device 2 Main body 3 Blower 4 Upwind model block area 41 Model block 42 Drive means 43 Vertical movement motor 46 Rotational movement motor 5 Measurement area 6 Gap

Claims (2)

A measurement area that reproduces the construction structure and the construction site where the construction structure is constructed,
A blower that blows wind toward the measurement area,
A wind tunnel experimental device including an upwind model block region formed between the measurement region and the blower.
In the measurement area, a measuring tool for measuring wind information is arranged.
In the upwind model block region, the building height and terrain undulations in the upwind range are reproduced by a plurality of model blocks that can be raised and lowered according to the three-dimensional shape data representing the roughness shape of the ground surface. The road or open space is reproduced ,
Wherein below the wind tunnel floor level upwind model block area, and wherein the Rukoto elevating motor, and the rotational movement motor has not been installed, wind tunnel was. The wind tunnel experiment according to claim 1, wherein the elevating height of the model block is determined by the height of the structure having the largest ratio of the dominant projected area within the range reproduced by the model block. apparatus.

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