JPS61139740A - Wind tunnel - Google Patents

Abstract

PURPOSE:To make it possible to freely set wind velocity to the wind in a tunnel not only in an up-and-down direction but also in a right-and-left direction, by providing a blower for sending a wind toward one tunnel end part mounted in each tunnel divided by a dividing plate and the controller for controlling the blow amount of the blower. CONSTITUTION:Horizontal dividing plates 14 and vertical dividing plates 15 are assembled in a grid pattern at one end side of a tunnel 11 and attached to the wall of the tunnel 11. Blowers 16 are arranged to the sections formed by the dividing plates 14, 15. A variable speed motor is used as the motor of each blower 16 and the number of rotations of the motor can be freely set by a controller. The number of rotations of each blower is determined so as to be set to shear 10 having to be reproduced and, in the same way, by determining the number of rotations of the blowers 16 adjacent in the horizontal direction, non-uniform shear is reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wind tunnel, and particularly to a wind tunnel that is optimal for use in smoke diffusion tests and the like.

[Conventional technology]

In order to prevent air pollution caused by exhaust gases emitted from power plants, chemical factories, etc., it is necessary to qualitatively and quantitatively understand the diffusion status of these polluted exhaust gases in the atmosphere and on the ground surface, and to analyze location conditions, scale, etc. It is necessary to obtain data to determine the most effective and economical chimney installation location, height, exhaust gas emission rate, etc.

Methods for obtaining such data include calculation methods, on-site testing methods, and model testing methods.

As a calculation method, Salaton (5utton)
Theoretical formulas, board formulas, and the British Met Office's empirical formulas have been published, but none of them take into account the influence of topography. In addition, there have recently been cases in which the effects of topography on these two areas have been determined through numerical analysis using computers, but in both cases verification through experiments is required.

The field test method cannot be tested until after the actual chimney has been constructed, and conducting tests in a wide area with complex topography would be extremely costly and labor intensive.

Moreover, the chimney height.

It is difficult to freely choose the wind direction, etc.

− Data can only be obtained at the location.

Tests using models include discharging gas from a chimney model and observing the gas diffusion situation with the naked eye to understand qualitatively, or quantitatively measuring the concentration by suctioning the gas. Is going.

FIG. 4 shows an outline of this type of experiment using a conventional wind tunnel.

The wind 2 generated by the blower 1 is once diffused by the diffusion cylinder 8 and then condensed by the contraction cylinder 4, and is discharged into the measurement cylinder 5 as a parallel flow. Inside the measuring cylinder 5.

Roughness 6 to control ground friction and chimney model to discharge tracer gas 7. Building model 8. So-called terrain models such as a ground surface model 9 are arranged.

Although the details are omitted, the state of the diffusion of the tracer gas can be determined by applying a color-changing reagent to the surface of the ground, and after each meeting, the concentration is determined by suctioning the gas. There is.

In tests carried out in this way, the wind acting on the terrain model must be reproduced in the same way as the natural wind. The wind speed of natural wind is almost zero at the ground due to ground friction, slightly higher at higher places, and faster at higher places. This wind speed distribution in the vertical direction is called a shear, and is shown at 10 in the wind tunnel. Although the shape of this shear changes depending on weather conditions, the shape of the shear 10 within the measurement cylinder 5 determines the diffusion situation and is extremely important in model tests.

Furthermore, depending on the topography upwind of a chimney or the like, the horizontal shape of the windshield may not be uniform.

[Problem that the invention seeks to solve]

Conventionally, the shape of the shear 10 in the wind tunnel has been controlled using only roughness 6. In other words, in order to give the same shear shape as natural wind to the wind that has been made uniform at the wind contraction cylinder 4, it was necessary to reduce the wind speed near the ground to zero at an early point, and then wait for the boundary layer to develop. . Therefore, it is necessary to make the measuring cylinder 5 longer.

Also, the so-called "power law" states that the wind is faster upwards.
I could only obtain a shear shape that suited my needs.

Furthermore, cases in which horizontally non-uniform shear shapes must be obtained have rarely been reproduced.

[Means for solving problems]

The present invention has a long trunk installed substantially horizontally.

A dividing plate arranged horizontally and vertically at one end of the compatriot and dividing the inside of the cylinder into a plurality of upper, lower, left and right parts, and a blower installed in each of the cylinders divided by the dividing plate and blowing air toward the other end of the cylinder. This wind tunnel is equipped with a controller that adjusts the amount of air blown by the blower.

[Effect]

The wind tunnel body of the present invention is installed horizontally.

One end is divided into multiple sections by a dividing plate into upper, lower, left, and right sections. There are 2 blowers whose air volume is adjusted by the controller.
It is installed inside each divided torso, and is designed to send air toward the other end of the torso.

Therefore, it is possible to create wind at different speeds in the vertical and horizontal directions within the shell.

〔Example〕

The present invention will now be described with reference to an embodiment of the apparatus shown in FIGS. 1 to 3.

11 is a long body installed approximately horizontally, and has a bell mouth 12. at one end (left end in the figure) for suction. A duct 13 with an enlarged diameter for discharge is connected to the other end. Reference numeral 14 denotes a horizontal dividing plate, and numeral 15 denotes a vertical dividing plate, which are arranged in a grid pattern at one end of the body 11 and are attached to the wall. Reference numeral 16 denotes a blower, which is arranged in each section formed by the dividing plates 14 and 15.

Incidentally, each of the motors of the blower 16 has a variable speed, and the rotation speed can be freely set by a controller (not shown). Furthermore, anemometers 17 are placed in front of the blowers 16, and the blowers 16 are controlled via the controller 18 so that the wind speed reaches a specified speed.

Now, tests are conducted in the wind tunnel constructed in this manner in the same way as in the past. That is, similar to FIG.

Chimney model inside the shell 117. Building model 8. A so-called terrain model such as the ground surface model 9 is placed, and a test is performed by discharging tracer gas.

By changing the rotational speed of the blower 16 in the vertical direction, the wind 2 acting on the model differs in the vertical direction, so the rotational speed of the blower 16 is determined so as to obtain the shear 10 to be reproduced. Similarly, non-uniform shear can be reproduced by determining the rotational speeds of horizontally adjacent blowers 16.

In other words, given the "non-uniform shear" which is the local weather condition to be reproduced, the wind speed that each fan 7 should generate in the vertical and horizontal directions is set (this is called the set wind speed). Ru. Since the pressure distribution inside the wind tunnel measurement body 11 becomes non-uniform, the speed of the generated wind differs even if the rotational speed of the blower 16 is the same. For this reason, the wind speed is detected by the anemometer 17 so as to reach the "set wind speed", and the motor is controlled by the controller 18 to increase or decrease the rotation speed of the blower 16 so that the difference from the set wind speed disappears.

Since it can be set freely, it is effective for tests that require shear adjustment, such as diffusion tests.

[Brief explanation of drawings]

FIG. 1 is a diagram of a wind tunnel showing one embodiment of the present invention. FIG. 2 is a sectional view taken along I[-I in FIG. 1, FIG. 3 is an enlarged view of the main part of FIG. 1, and FIG. 4 is a diagram of a conventional wind tunnel. 11...Body, 14...Horizontal dividing plate, 15...Vertical dividing plate. 16...Blower, 18...75H in controller tube 2

Claims (1)

[Claims] A long torso installed approximately horizontally, a dividing plate placed horizontally and vertically at one end of the torso to divide the inside of the torso into multiple parts, top, bottom, left and right, and equipment inside each torso divided by the dividing plate. A wind tunnel characterized by comprising: a blower that sends air toward the other end of the body; and a controller that adjusts the amount of air blown by the blower.