JP2003194675A - Gas aspiration device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas aspiration device capable of solving the problems of a conventional device that a large number of members are required for water level adjustment of a gas aspiration pod for generating an inspiration negative pressure and that measurement accuracy is owered because of aged material deterioration or dust clogging, concerning the gas aspiration device for aspirating airflow into a measuring device for measuring the trace gas concentration in the airflow flowing on a topography model in a wind tunnel. <P>SOLUTION: This gas aspiration device is provided with pairs of cylindrical gas aspiration pods installed in liquid vessels with bottom faces separated respectively from the bottom faces of the two liquid vessels and with closed upper faces to which piping for connecting respectively to a test tube is connected, and a passage switching mechanism interposed in the piping, for communicating the gas aspiration pods in the liquid vessel on the liquid level lowering side with the test tube, and discharging the air in the pods in the liquid vessel on the liquid level rising side to the outside. Hereby, the secular deterioration of members and the member exchange frequency can be reduced, and the material cost and the working time can be reduced with a simple structure, the small number of members and excellent maintainability. In addition, a passage resistance change in a measuring system caused by dust residence or the like can be reduced, and flow unbalance of the air aspirated into the test tube is reduced, to thereby keep the measurement accuracy and to perform accurate measurement for a long time. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diffusion wind tunnel, etc., and is emitted into the wind tunnel from a chimney model simulating a chimney, etc.
To detect the concentration of trace gas diffused in the air flow flowing in the wind tunnel and investigate the trace gas diffusion condition in the air flow, a gas sampling hole drilled at a measurement point set at a predetermined position on the floor surface of the wind tunnel. The present invention relates to a gas suction device for sucking an air stream from the air and introducing it into a test tube filled with a gas absorbing liquid.

[0002]

2. Description of the Related Art When constructing a power plant, etc., it is released into the atmosphere from a chimney erected at the power plant due to the topography around the site where the power plant is to be constructed and the natural environment that changes seasonally, especially the wind direction and wind speed. Preliminary research will be conducted on how the exhaust gas will flow around the planned construction site, and what kind of concentration it will have in the surrounding specific area, and how it will affect the environment around the planned construction site. Has been.

For this purpose, a terrain model including buildings around the planned construction site is manufactured and installed in a wind tunnel capable of simulating natural phenomena such as wind direction and wind speed around the planned construction site. In a wind tunnel that is producing an air flow that simulates the wind that is generated, a trace gas that simulates exhaust gas is emitted from a chimney model provided on a terrain model, and the state of diffusion of the emitted trace gas in the air flow or By investigating the trace gas concentration at the measurement points set on the terrain model, how the exhaust gas actually emitted from the chimney of the power plant into the atmosphere affects the environment around the construction site I try to predict that.

FIG. 7 shows that, in order to investigate the trace gas concentration in the airflow flowing on such a terrain model, the airflow is sucked from a measurement point set in the wind tunnel and diffused into the airflow. It is a figure which shows the wind tunnel and gas suction device conventionally used for introducing in the test tube provided in order to detect trace gas concentration. As shown in the figure, wind tunnel 0
A terrain model (not shown) (not shown) is provided on the floor surface inside 1, and a chimney model 02 is erected on the floor surface, and a trace gas 03 simulating exhaust gas emitted from the chimney, The chimney model 02 is designed to emit the wind into the air flow 04 that simulates the wind. The trace gas 03 released into the air flow 04 flows toward the leeward side of the chimney model 02 while diffusing in the air flow 04.

The chimney model 02 The wind tunnel on the leeward side 01 The trace gas 03 is located at the measurement point on the floor where the gas concentration measurement is required.
A gas sampling hole 05 for sucking the air flow 04 flowing while being diffused is previously opened. Also,
One end of a sampling tube 06 is connected to the gas sampling hole 05, and the other end side is a test tube 0.
No. 7, and the test tube 07 is immersed in the gas absorbing liquid 08 for measuring the gas concentration. In addition, in the test tube 07, one end of the gas absorption liquid 0
A pipe 09 having an opening above 8 and having the other end connected to the flow path switching mechanism 010 is provided, and the test tube 07 is also connected to the flow path switching mechanism 010.

Further, the flow path switching mechanism 010 has two
One ends of the pipes 011a and 011b made of a book are connected to each other, and the other ends of the pipes 011a and 011b are connected to the upper portions of the gas suction pods 012a and 012b that are paired with each other, and the flow path switching mechanism 010 The test tube 07 and the gas suction pods 012d and 012
It communicates with either of b. Further, one ends of pipes 014a and 014b are connected to the respective bottom surfaces of the gas suction pods 012a and 012b, and the other ends of the pipes 014a and 014b are connected to the gas suction pod 01.
2a, chamber 015a installed at the bottom of 012b,
015b, respectively.

Further, one ends of pipes 016a and 016b are connected to the lower ends of the chambers 015a and 015b, and the other ends of the pipes 016a and 016b are quantitative feeders as shown in FIG. 7B. (roller)
The pump 017 is connected to a silicon tube 018 arranged in a part of the roller. Further, the gas suction pod 012 described above is provided with the same number of sets as the number of gas sampling holes 05 drilled on the floor surface of the wind tunnel 01 in order to suck the required gas suction point, in other words, the air flow 04. Water 013 is filled in the same amount as the volume of one gas suction pod 012, and can be further poured and discharged.

In the gas suction device having such a configuration, as one initial condition, one gas suction pod 012a is filled with water 013 in an amount such that the water level is set at the upper end, and the flow path is switched. By operating the mechanism 010, the flow path from the pipe 09 to the suction pod 012a is opened, and on the other hand, the pipe 011b provided above the suction pod 012b bypasses the inside of the flow path switching mechanism 010 to make the suction pod. The air accumulated in 012b is set to flow to the outside.

After setting the initial conditions in this way, the air flow is reduced to zero.
When the trace gas 03 is discharged from the chimney model 02 into the air flow 04 and the pump 017 is rotated in the state where the number 4 is generated, the water level of the water 013 in the gas suction pod 012a is lowered and the water level in the suction pod 012b is decreased. Rises and the water level drops accordingly.
Negative pressure is generated in 2a, the air in the test tube 07 communicating with the gas suction pod 012a is sucked, and is introduced into the gas suction pod 012a, so that negative pressure is generated in the test tube 07 and the test tube In the gas absorption liquid 08 of 07, the air flow 04 in the wind tunnel 01 is sucked in a constant amount through the sampling tube 06, and the trace gas 0 diffused in the air flow 04
3 melts.

At this time, the trace gas 03 diffused in the air flow 04 is completely dissolved in the gas absorbing liquid 08, and the electric conductivity of the gas absorbing liquid 08 is changed by this dissolution, so that the gas absorbing liquid 08 is changed. The concentration of the trace gas 03 in the gas absorbing liquid 08 can be obtained by measuring the electric conductivity of the test tube 08, and by further obtaining the flow rate of the air flow 04 sucked in the test tube 07, the test tube It is possible to detect the concentration of the trace gas 03 in the air flow 04 flowing over the measurement point in the wind tunnel 01 where the gas sampling hole 05 communicating with 07 is provided.

In addition, this gas suction device is designed so that an equal amount of air flow 04 is sucked into any of the test tubes 07 and can be continuously used. That is, when the water level in the gas suction pod 012a of the same size (volume) drops to the lower end in order to generate the same negative pressure in the test tube 07 as described above, the other gas Since the water level in the suction pod 012b rises to the upper end, at this time, the flow passage from the pipe 09 to the suction pod 012b is opened, and the pipe 011a provided above the gas suction pod 012a is When the test tube 07 is bypassed in the switching mechanism 010 to make the test tube 07 a negative pressure, the test tube 07
The switching operation of the flow path switching mechanism 010 is performed so that the air sucked from the inside and flowing into the gas suction pod 012a flows to the outside.

Thus, after switching the flow path switching mechanism 010, if the pump 017 is rotated in the opposite direction to the above, the water level in the suction pod 012b is lowered, and the gas suction pod 0
Since the water level in 12a rises, a negative pressure is again generated in the test tube 07, which communicates with the gas suction pod 12b whose water level is lowered, so that the gas absorbing liquid 08 in the test tube 07 again has the wind tunnel 01 inside. This is because the airflow is melting.

However, in the conventional gas suction device,
There were the following defects.

The silicon tube 018 disposed in the pump 017 needs to be replaced periodically because the material deteriorates due to aging, and moreover, it is installed on the floor surface as described above. To perform the wind tunnel test to measure the trace gas 03 concentration at the measurement point of
Since it is necessary to use as many as 00 silicon tubes 018, the material cost and the working time become large.

From the test tube 07 to the pump 017, the flow path switching mechanism 010 and the pipes 09, 011, 014, 01
6, the gas suction pod 012, the chamber 015, and many other members are provided, and the resistance in the flow path is likely to change due to aging deterioration or clogging due to water stains, dust, etc. There is a difference in the negative pressure that can be generated by the pod 012, and this negative pressure causes a flow rate imbalance of the air flow 04 that is sucked into the test tube 07, so that it is included in the air flow 04 at the position of each gas sampling hole 05. The accurate concentration of the trace gas 03 can no longer be measured.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the conventional gas suction device, the present invention can reduce the frequency of replacement with less deterioration of the material due to aging, and the structure is simple and the member Since the number of points can be reduced, maintenance is excellent, material costs and work time can be reduced, and fluctuations in the flow path resistance of the measurement system due to aging deterioration or clogging with dust etc. are reduced, and suction from the wind tunnel to the test tube is possible. An object of the present invention is to provide a gas suction device that reduces the flow rate unbalance of the generated air flow to maintain the measurement accuracy and enables more accurate measurement.

[0017]

Therefore, the gas suction device of the present invention has the following means.

(1) From a chimney model installed in a wind tunnel generating an air flow that simulates the wind generated in a specific area,
The trace gas that simulates the exhaust gas is released into the air flow, and the concentration of the trace gas that diffuses in the air flow that flows through multiple measurement points, which is set at a predetermined position in the wind tunnel, is simulated by simulating a specific position in the area. In order to perform each measurement, in the gas suction device that suctions the air flow into the test tube provided in correspondence with the number of measurement points to perform the trace gas concentration measurement from the gas sampling holes provided in each of the multiple measurement points, the liquid in both directions Two liquid tanks that are connected by a pipe with a pump that can transfer water, and that allows the liquid discharged from one to be injected into the other by the pump operation, and the opened bottom surface is separated from the bottom surface of the liquid tank into the liquid tank. The pipes for connecting the test tubes are connected to the upper surfaces of the installed and closed pipes, respectively, and a pair of cylindrical gas suction pods are interposed between the pipes to lower the liquid level. The gas suction pod installed in the liquid tank is connected to the test tube, and the liquid level is rising as the liquid level in one liquid tank is lowered. Bypass the air in the gas suction pod installed in the other liquid tank. And a flow path switching mechanism for discharging to the outside.

(A) As a result, the concentration of the trace gas diffused in the air flow flowing through a large number of measuring points in the wind tunnel simulating a specific position can be continuously measured, and the exhaust gas discharged from the power plant or the like can be measured. The impact on the installation area can be predicted, the deterioration of the component materials due to aging is small, the frequency of member replacement can be reduced, and the structure is simple and the number of members can be reduced, resulting in excellent maintainability and material cost. And the working time can be reduced. In addition, fluctuations in the flow path resistance of the measurement system due to aging deterioration, dust retention, etc. can be reduced, so flow rate imbalance of the air flow sucked from the sampling holes into the test tube is less likely to occur, measurement accuracy is maintained, and long-term measurement is maintained. You will be able to measure accurately.

Further, the gas suction device of the present invention has the above-mentioned (1).
In addition to the above means, the following means were adopted.

(2) The gas suction pod closes the escape control valve for releasing the air flowing into the gas suction pod to the outside when the liquid level in the liquid tank is lowered. It should be provided on the upper end of the suction pod.

(B) As a result, in addition to the above (a), as the liquid level in the gas suction pod rises as the liquid level in the liquid tank rises, the air flowing into the interior is released to the outside. At this time, it is possible to reduce that air adheres to and remains on the inner peripheral side of the upper end of the gas suction pod, and the gas suction pod is filled with water that does not contain air, and is generated in the test tube when the liquid level of the gas suction pod drops. The magnitude of the negative pressure that can be generated can correspond to the liquid level accurately, and an accurate suction amount into the test tube can be set, allowing accurate measurement.

Further, the gas suction device of the present invention has the above-mentioned (1).
In addition to the above means, the following means were adopted.

(3) The gas suction pod is provided so as to project upward from the upper end, the pipe is connected to the upper end, and the tapered portion in which a conical space is formed and the inside of the gas suction pod are vertically moved. A float having a conical portion provided above to rise and fall in response to the moving liquid level and to fit into the tapered portion when sealing and to close the pipe is provided.

(C) As a result, in addition to the above (a), when the liquid level is raised by injecting the liquid into the liquid tank, the liquid level in the gas suction pod suddenly rises due to an erroneous operation or the like. Even if there is, since the conical part of the float fits the taper part and closes the pipe, it is possible to prevent the backflow of the fluid into the test tube and reduce the loss due to the re-preparation of the experiment that may occur due to the backflow. Can perform efficient tests.

Further, the gas suction device of the present invention has the above-mentioned (1).
In addition to the above means, the following means were adopted.

(4) The gas suction pod is made of at least two types having different inner diameters.

(D) As a result, in addition to the above (a), when measuring the gas concentration in the air flow flowing through a plurality of measurement points in the wind tunnel having different trace gas concentrations, it is possible to measure at the measurement point with a high gas concentration. Uses a gas suction pod with a small inner diameter,
A test using a gas suction pod with a large inner diameter can be performed for measurement at a measurement point with a low gas concentration, which allows an air flow proportional to the cross-sectional area of the gas suction pod to be sucked into the test tube from the wind tunnel, Even if the volume of the gas absorbing liquid filled in the tube is constant, the concentration of the trace gas absorbed in the gas absorbing liquid can be kept within the measurement range of the concentration measuring device, and the air flow suction into the test tube is repeated. Alternatively, the time for diluting the gas absorbing liquid is not required, and an efficient test can be performed.

Further, the gas suction device of the present invention has the above-mentioned (4).
In addition to the above means, the following means were adopted.

(5) The gas suction pod is made of at least two types having different inner diameters, and a film-like member capable of adjusting the contact angle with the liquid is spread on the inner peripheral surface of at least the small diameter gas suction pod. I was supposed to.

(E) As a result, in addition to the above (d), when gas suction pods having different inner diameters are used due to the surface tension of the liquid flowing into the inside, a gas suction pod that causes a difference in liquid level is used. Also in the test performed by selecting the membrane member, the liquid level can be kept constant regardless of the inner diameter of the gas suction pod, the accurate suction amount can be set in the test tube, and the test accuracy can be improved. It will also be possible to perform a test in which a high concentration gas is diffused using a gas suction pod with an extremely small inner diameter.

Further, the gas suction device of the present invention has the above-mentioned (1).
In addition to the above means, the following means were adopted.

(6) The gas suction pod is made of at least two types having the same diameter and different lengths, and the lowered internal liquid level reaches the lower end of the lower end of the gas suction pod having a short length. At this time, an automatic opening / closing mechanism for closing the opening provided on the bottom surface is provided.

(F) As a result, in addition to the above (a), the air suction speed at all measurement points into the test tube is kept constant,
Moreover, since the suction amount can be set according to the gas concentration at the measurement point, the test time can be shortened and the test accuracy can be improved.

Further, since the automatic opening / closing mechanism is provided, even if the liquid level in the liquid tank is lowered below the lower end of the short gas suction pod, the liquid remains in the short gas suction pod and the internal pressure fluctuation is prevented. Along with being able to reduce the number, a long suction pod can suction a large amount of air flow.

Further, the gas suction device of the present invention has the above-mentioned (1).
In addition to the means of (6) to (6), the following means were adopted.

(7) The liquid poured into the liquid tank and discharged is water or a liquid having a viscosity higher than that of water.

(G) As a result, in addition to the above (a), when water is used as the liquid, the test preparation is simplified, the test cost can be reduced, and a liquid having a viscosity higher than that of water is used as the liquid. When used, the intermittent change of the liquid level caused by the pulsation of the pump that changes the liquid level of the liquid tank can be minimized, and the test accuracy can be further improved.

[0039]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a gas suction device of the present invention will be described below with reference to the drawings. The same or similar members as those used in the conventional gas suction device described with reference to FIG. 7 and the same or similar members as those used in the above-described embodiment are the same. The reference numerals are given and the description is omitted as much as possible.

FIG. 1 is a side view of a gas suction device showing a first embodiment of the present invention. As shown in the figure, in the gas suction device of the present embodiment, a water tank 19 as two liquid tanks is provided.
a and 19b are provided, and instead of the conventional gas suction pod 12, a plurality of gas suction pods 20 having an opening at the lower end and having the same inner diameter and the same length are arranged in each of the water tanks 19a and 19b.

In other words, the gas suction pod 20 includes a set of gas suction pods 20a and 20b arranged in the water tanks 19a and 19b, respectively.
5, the same number of gas suction pods 20 are provided.
a and 20b are pipes 01 at the upper end similar to those shown in FIG.
1 are connected to the same flow path switching mechanism 010. Further, from the bottom of the water tank 19, the pipe 23
Is provided, and the two water tanks 19a and 19b are connected by the pipe 23 via a pump 24 provided on the way.

In the gas suction device of the present embodiment having such a configuration, as an initial condition, the water level 22 of the water 21 in one water tank 19a is set to the upper end of the gas suction pod 20a arranged in this water tank 19a. Up to. Further, since the water level 25 of the other water tank 19b needs to be set at a position where the lower end of the gas suction pod 20b arranged in the water tank 19b is immersed, an appropriate amount of water 21 is poured.

Further, the flow passage switching mechanism 010 opens the flow passage from the pipe 09 to the above-mentioned gas suction pod 20a, and the pipe provided above the gas suction pod 20b arranged in the other water tank 19b. 11b is bypassed in the flow path switching mechanism 10 so that the air flowing into the gas suction pod 20b flows out as the water level 25 in the gas suction pod 20b rises.

In the gas suction device in which such initial conditions are set, the pump 24 is operated to move the water 21 in the water tank 19a and the water tank 19b to lower the water level 22 of the water tank 19a at a constant speed. As the water level 22 descends, the pressure inside the gas suction pod 20a becomes negative, and the pipe 0
11a, the flow path switching mechanism 010, and the air above the gas absorbing liquid 08 filled in the test tube 07 connected through the pipe 09 are sucked into the gas suction pod 20a, so that the inside of the test tube 07 Becomes negative pressure, and the air flow 04 flowing above the gas sampling hole 05 is sucked into the test tube 07 through the sampling tube 06 and diffused into the air flow 04 in the gas absorbing liquid 08 filled in the test tube 07. The trace gas 03 that is flowing dissolves at a constant flow rate.

Further, this gas suction device can be continuously used like the conventional gas suction device. That is, as described above, the water tank 19 is operated by the operation of the pump 24.
In the process of lowering the water level 22 of a, the water 21 discharged from the pump 24 is flowing into the other water tank 19b.
When the water level 22 of 9a falls to a required position, the water level 25 of one water tank 19b rises to the upper end of the gas suction pod 20b.

At this point, the flow path switching mechanism 010
This time, the flow path from the pipe 09 to the gas suction pod 20b is opened, and the pipe 01 provided at the upper part of the suction pod 20a
1a performs an operation of bypassing in the flow path switching mechanism 010 and lowers the water level 22 in the gas suction pod 20a so that the air that has flowed into the inside is discharged to the outside, and then the pump 24 is returned to the previous state. Is operated in the opposite direction, the water level 25 of the suction pod 20b is lowered, so that gas suction is performed through the pipe 011b, the flow path switching mechanism 010, and the pipe 09, and the inside of the test tube 07 is again sucked by the negative pressure. The trace gas 03 diffused in the air flow 04 of the wind tunnel 01 is melted into the inside of 08, and the concentration of the trace gas 03 in the continuous air flow 04 can be measured.

As described above, in the gas suction device of the present embodiment, the gas suction pod 01 including the gas suction pods 012a and 012b with the lower ends opened in the two water tanks 19 is provided.
2 are arranged in the same number as the number of gas sampling holes 05, in other words, the same number of measurement points for measuring the concentration of the tracer gas 03, and the upper end of each of the one set of suction pods 012a and 012b is flow path switching. Pipe 0 through mechanism 010
11a and 011b are connected, and further, a pipe 23 is provided from the bottom surface of the water tank 19, and two water tanks 19a and 19b are connected via a pump 24. Compared to a suction device, the structure is simpler and the maintainability can be improved.

Furthermore, since the number of members from the gas suction pod 20 to the test tube 07 can be reduced, the test tube 07 for measuring the gas concentration in the air flow 04 due to deterioration over time and clogging with water stains and dust is sucked. The flow rate imbalance of the generated air flow 04 is unlikely to occur, and the concentration of the gas diffused in the air flow 04 can be measured with high accuracy.

Next, FIG. 2 is a side view of a gas suction device showing a second embodiment of the present invention. As shown in the figure, in addition to the configuration of the gas suction device of the first embodiment described above, the gas suction device of the present embodiment has the gas suction pods 20a, 2
A relief control valve 26 for bleeding air is installed at the upper end of each 0b.

As described above, in the gas suction device of the first embodiment, the water level 22 of the water 21 in one of the water tanks 19a is set at the upper end of the gas suction pod 20a installed in the water tank 19a as the initial gas condition. At that time, air tends to adhere to and remain on the inner peripheral surface of the upper end portion of the gas suction pod 20a, and the negative pressure that can be generated in the test tube 07 by lowering the water level 22 accordingly. The size of the air flow becomes smaller, so the air flow sucked into the test tube 07 becomes 0.
It is expected that the flow rate of No. 4 will become small and will cause an error in the accurate suction amount setting.

Therefore, in the gas suction device according to the present embodiment, when the water level in the water tank 19b is lowered to raise the water level in the water tank 19a, the relief control valve 26a is set to the oven and air is sucked into the gas suction pod 20a. I tried not to leave as much as possible. That is, when lowering the water level in the water tank 19a for gas suction, the escape control valve 26a is closed and the test tube 0
In order not to hinder the generation of negative pressure in 7, the relief valve 26b installed on the other water tank 19b side is opened so that air does not remain in the gas suction pod 20b.

Thus, in addition to the gas suction device of the first embodiment, the gas suction device of the embodiment has an escape control valve 26 for bleeding air at the upper end of the gas suction pod 20.
By installing the, the air does not remain on the outer peripheral side of the upper end when water is injected into the gas suction pod 20, and a more accurate suction amount can be set by the negative pressure generated by the gas suction pod 20 during drainage. become.

Next, FIG. 3 is an enlarged side view of the upper part of the gas suction pod used in the gas suction device of the third embodiment of the present invention. As shown in the figure, the upper portion of the gas suction pod 27, which is provided in the gas suction device of the present embodiment, has a tapered shape in which the diameter is reduced upward, and the tapered portion 27a has a tapered shape. Pipe 01 described above at the top
1 is connected. Also, the gas suction pod 2
A float 28 including a bottom plate portion 28a having a diameter substantially equal to the inner diameter of the gas suction pod 27 and a conical portion 28b having the same tapered shape as the taper portion 27a is disposed in the inside of the gas suction pod 27.

Air flow to test tube 07 by gas suction device 0
At the time of suction of No. 4, the water level in the gas suction pod 27 is set to a required height as an initial condition. At that time, if the water injection into the gas suction pod 27 does not stop for some reason, the water 21 is piped. It may flow back to the test tube 07 through 011 and 09, and the experiment preparation is redone, resulting in a great loss. However, since the gas suction device of the present embodiment is configured as described above, the float 28 rises as the water level rises due to water injection, but the bottom plate portion 28a of the float 28 has the upper end of the gas suction pod 27. Is reached, the conical portion 28b fits into the tapered portion 27a,
Since it serves as a mechanical stopper at the upper part of the gas suction pod 27, it is possible to prevent the water 21 from mistakenly flowing back to the test tube 07, and it is possible to eliminate the loss such as the repetition of the experiment preparation. Become.

Next, FIG. 4 is a side view showing a gas suction device according to a fourth embodiment of the present invention. As shown in the figure, a gas suction pod 29 having a large inner diameter is provided in each of the water tanks 19a and 19b.
Large-diameter gas suction pod 2 consisting of 1a and 291b
9 and the small-diameter gas suction pods 30 each of which has a small inner diameter and each of which has a small inner diameter are arranged in plural sets. The gas suction pods 29 and 30 may be installed in a desired number of groups with the required inner diameter instead of the two inner diameters.

As described in the prior art, when measuring the diffusion concentration of the trace gas 03 that is emitted from the model chimney 02 into the airflow 04 in the wind tunnel 01 and diffuses in the airflow 04, the model chimney 02 will naturally be measured. The closer it is, the higher the concentration,
As the distance becomes longer, the trace gas 03 is diffused in the air flow 04 and the concentration becomes smaller. Further, the diffusion concentration of the trace gas 03 in the air flow 04 is 0 when the trace gas 0 diffused in the gas absorption liquid 08 in the test tube 07 in the air flow 04.
After dissolving 3, the electric conductivity of the gas absorption liquid 08 is measured and obtained. When the concentration of the trace gas 03 is small, gas suction is repeated until a large amount falls within the measurement range of the electric conductivity meter. The air flow 04 needs to be sucked into the test tube 07.

On the other hand, when gas suction is repeated until the concentration at the measurement point provided with the gas sampling hole 05 provided far from the model chimney 02 is measured, the gas is sucked at the measurement point near the model chimney 02. On the contrary, the concentration of the trace gas 03 becomes too high, so that it does not fall within the measurement range of the conductivity meter.

In such a case, the test tube 0 in which the trace gas 03 in the air flow 04 sucked from the gas sampling hole 05 installed at the measurement point near the chimney model 02 is dissolved
It is necessary to dilute the gas absorbing liquid 08 in 7 to the measurable range of the conductivity meter. That is, depending on the experimental condition or the measurement point for measuring the concentration of the trace gas 03, the experiment time may be longer than usual because the gas absorption liquid 08 is required to be diluted in addition to the gas suction repetition time.

The gas suction device of the present embodiment is intended to eliminate such a problem, and trace gas 03
In the measurement of a measurement point where the gas concentration in the air flow 04 far from the chimney model 03 having a low concentration is low, the large-diameter gas suction pod 29 having a large suction amount per time is used, and the vicinity of the chimney model 02 where the gas concentration becomes high. In the measurement at the measurement point of, the small-diameter gas suction pod 3 has a small suction amount per time.
0 is used to suck the amount of the air flow 04 according to the installation position of the measurement point into the test tube 07 and dissolve the trace gas 03 into the gas absorption liquid 08 so that the concentration is within the measurement range of the conductivity meter. In this way, it is possible to shorten the repetition time of the trace gas 03 suction and the thinning time of the absorbing liquid 08.

Next, FIG. 5 is a side view showing a gas suction device according to a fifth embodiment of the present invention. As shown in the figure, in the gas suction device according to the present embodiment, as in the gas suction device according to the fourth embodiment, one set of large-diameter gas suction pods 291a and 291b having large inner diameters is provided in the water tanks 19a and 19b. A plurality of gas suction pods 29 and a plurality of small-diameter gas suction pods 30 each of which has a small inner diameter are formed.

Incidentally, these gas suction pods 30 are also, if necessary, in other words, the air flow 04 sucked into the test tube 07.
It is also possible to provide a plurality of types having inner diameters determined according to the suction amount of
It is similar to that of the form. In addition, in the gas suction device of the present embodiment, the film-shaped member 34 is formed on the inner peripheral surface of the small-diameter gas suction pod 33, in which the inner diameter is particularly small and the influence of the capillary phenomenon (surface tension) on the water level 32 is large. I try to put it on.

That is, when the gas suction side plate of the fourth embodiment is used, when the water 21 in the water tank 19 is drained and the water level 31 is lowered to perform gas suction, if the gas suction pods 29, 30 have different inner diameters. As shown in FIG. 5B, the water levels 31 in the large-diameter gas suction pod 29 and the small-diameter gas suction pod 30,
It may happen that 32 is different during aspiration. This is due to the capillary phenomenon between the inner surface of the gas suction pod and the water 21,
In the large-diameter gas suction pod 30, the small-diameter gas suction pod 30 has a greater effect on the water level of the capillarity in the case of the small-diameter gas suction pod 30, so that the water level 32 of the small-diameter gas suction pod 30 becomes It becomes higher than the water level 31 of the large-diameter gas suction pod 29.

In this way, when there is a difference in the water levels 31, 32 between the large-diameter gas suction pod 29 and the small-diameter gas suction pod 30, the large-diameter gas suction pod 29 passes through the pipe 011.
Since the negative pressures generated in the test tubes 07 connected to the small-diameter gas suction pod 30 have different magnitudes, the gas that is normally set by the magnitude of the negative pressure and the inner diameter of the gas suction pod 30 is set. There is a possibility that the suction volume cannot be set accurately.

Therefore, in the gas suction device of this embodiment, as shown in FIG. 5 (a), a film-shaped film is formed on the inner peripheral portion of the small-diameter gas suction pod 33 where the effect of the capillary action on the water level is particularly large. By spreading the member 34 and adjusting the surface tension and the contact angle of the water 21 and the member 34, there is no difference in the water level caused by the capillary phenomenon, and even when the gas suction pods 30 having different inner diameters are used, the gas suction is performed. The water level inside the gas suction pod 30 at the time (drainage) can be kept constant.

As a result, an appropriate amount of gas is sucked into the test tube 07. Therefore, even when the test is performed by mixing the large-diameter gas suction pod 29 and the small-diameter gas suction pod 33, the water level 31, gas The magnitude of the negative pressure generated in the test tube 07 can be made constant regardless of the diameter of the suction pod, the amount of gas suction can be set accurately, and the experimental accuracy can be improved.

Next, FIG. 6 is a side view showing a gas suction device according to a sixth embodiment of the present invention. As shown in the figure, in the gas suction device of the present embodiment, as in the gas suction devices of the first and second embodiments, the gas suction pods having the same inner diameter are arranged in the water tanks 19a and 19b. However,
The length of this gas suction pod is different from that of the first and second embodiments, and is changed according to the measurement point position.

As described above, in the fourth embodiment, by disposing the gas suction pods 29 and 30 having arbitrary inner diameters in the water tank 19 in accordance with the position of the measuring point, it is possible to obtain the appearance near the chimney model 02. And trace gas 03 into airflow 04
At a measurement point position where the diffusion concentration is low, a large amount of air flow 04 is sucked into the test tube 07, and as described above, the amount of trace gas mixed in the air flow 04 that can be measured by the conductivity meter is used as the gas absorption liquid 08. The time required for repeated suction can be shortened by eliminating the repeated suction, and conversely, a small amount of the air flow 04 is passed through the test tube 07 when measuring the measurement point position where the trace gas 03 has a high diffusion concentration. The amount of the trace gas 03 that is sucked into and absorbed by the gas absorbing liquid 08 is reduced, and the trace gas concentration of the gas absorbing liquid 08 is too high, which hinders diffusion concentration measurement. The working time is shortened by shortening the thinning time of the gas absorbing liquid 08.

However, in such an embodiment, it is expected that a problem different from the problem described in the fifth embodiment will occur because the gas suction pods 29, 30 have different inner diameters. In other words, by uniformly lowering the water level 31 by the pump 24, the gas suction pod 29,
The air flow 04 sucked into the test tube 07 by the negative pressure generated in the air is exhausted from the inside of the test tube 07 which has the same inner diameter as the inner diameters of the gas suction pods 29 and 30. Since the amount of the air flow is different, the suction flow rate of the air flow 04 sucked into the test tube 07 is different, and the suction speed of the air flow 04 changes depending on the measurement point.

As described above, when the ratio of the airflow suction speed to the speed of the wind tunnel 01 airflow 04 is increased to some extent, the accurate diffusion concentration at the measurement point may not be measured. That is, if the suction speed is too high with respect to the speed of the air flow 04, the air flow 04 sucked into the test tube 07
Sucks not only the airflow 04 flowing on the floor surface (topographic model) above the sampling holes 05 but also the airflow mixed with the trace gas 03 diffused in the space away from the floor surface, This is because the concentration of the trace gas 03 mixed with the air flow 04 at the measurement point position on the surface cannot be measured.

Therefore, in the gas suction device of the present embodiment, as described above, the long gas suction pod 35 having the same inner diameter and the long length and the short gas suction pod 36 having the short length are used.
Are arranged in the water tanks 19a and 19b. That is, one set of long gas suction pods 35a, 35b or short gas suction pods 36a, 36b respectively arranged in the water tanks 19a, 19b is used as a set, and the length is determined in consideration of the trace gas 03 concentration at the measurement point position. These are arranged in a plurality of sets of water tanks 19a and 19b. An automatic opening / closing mechanism 37 is installed at the lower end of the short gas suction pod 36 having a short length.

The gas suction device of the present embodiment has the above-mentioned structure, and the pump 24 is operated to operate the water tank 1.
The water 21 of 9a is drained and gas suction is started. At this time, when the water level 22 reaches the lower end of the short gas suction pod 36a, the automatic opening / closing mechanism 37 is closed to stop the gas suction by the short gas suction pod 36a. In the long gas suction pod 35a, the gas suction is continued as it is, and the gas suction is performed until the water level 22 reaches the lower end of the long pod 35a.

When the water level reaches the lower end of the short gas suction pod 36a, the water 21 discharged from the water tank 19a is injected into the other water tank 19b, and the water level 25 reaches the lower end of the short gas suction pod 36b. Therefore, the automatic opening / closing mechanism 37 provided at the lower end of the short gas suction pod 36b is opened to start water injection into the short gas suction pod 36b. In this way, the gas suction pod 3
Since 5 and 36 suck the air in the test tube 07 having the same flow rate, in the gas suction device of the present embodiment, the gas suction speed at the measurement point can be arbitrarily set with the suction amount being constant. As a result, the experiment time can be shortened and the experiment accuracy can be improved.

Next, a gas suction device according to the seventh embodiment of the present invention will be described. The gas suction device of the present embodiment has substantially the same configuration as the gas suction device of the first embodiment shown in FIG. 1, and the liquid filled in the water tank 19 is the same as the gas suction device of the first embodiment.
In the form, it is water 013, whereas in the present embodiment, it is filled with a highly viscous liquid.
By doing so, the intermittent change of the water level 22 due to the pulsation of the pump 24 described in the tenth embodiment can be minimized by viscous action.

The use of such a highly viscous liquid can be applied not only to the first embodiment but also to the gas suction devices of the second to tenth embodiments.
By using such a highly viscous liquid, more accurate gas concentration measurement can be performed.

[0075]

As described above, according to the gas suction device of the present invention, the air flow in the test tube for measuring the concentration of the trace gas diffused in the air flow flowing through the plurality of measurement points provided at the predetermined positions in the wind tunnel is achieved. In a gas suction device that sucks
Two liquid tanks connected by a pipe with a pump so that they can be poured and drained from one side to the other by its operation, and the bottom surface of the opening is installed in the liquid tank separately from the bottom surface of the liquid tank. Cylindrical gas suction pods that form a set by connecting the pipes to be connected to the test tubes respectively, and the gas suction pods installed in the liquid tank on the liquid level lowering side that are interposed in the pipes are connected to the test tubes and the liquid level rises. A flow path switching mechanism that bypasses the air in the gas suction pod installed in the liquid tank on the side and discharges it outside is provided.

As a result, it is possible to reduce the deterioration of members over time, reduce the frequency of member replacement, simplify the structure, reduce the number of members, maintainability, and reduce the material cost and working time. Further, it is possible to reduce fluctuations in the flow path resistance of the measurement system due to deterioration over time, accumulation of dust, and the like, reduce the flow rate imbalance of the air flow sucked into the test tube, maintain the measurement accuracy, and perform accurate measurement for a long time.

Further, in the gas suction device of the present invention, the escape control valve for discharging the air flowing into the gas suction pod to the outside when the gas suction pod rises in the liquid level in the liquid tank is provided on the upper lid.

As a result, it is possible to reduce the adherence and residue on the inner circumference of the upper end portion when air is released to the outside due to the rise in the liquid level in the gas suction pod, and the magnitude of the negative pressure that can be generated in the gas suction pod corresponds to the liquid level. It is possible to set the exact amount of suction into the test tube and perform accurate measurement.

Further, in the gas suction device of the present invention, the gas suction pod projects from the upper surface and has a pipe connected to the upper end thereof, and the tapered portion in which a conical space is formed therein and the liquid level inside the gas suction pod are moved up and down. Correspondingly, a float with a conical portion that rises and falls and that fits into the tapered portion when closing and closes the pipe is provided.

As a result, when the liquid in the liquid tank rises, even if the liquid level in the gas suction pod suddenly rises, the float fits into the taper part and closes the pipe, preventing backflow of the liquid into the test tube. Efficient tests can be performed without loss due to re-preparation.

Further, in the gas suction device of the present invention, the gas suction pod is made of at least two types having different inner diameters.

As a result, when measuring the gas concentration in the air flow at a plurality of measurement points in the wind tunnel with different trace gas concentrations, a small-diameter gas suction pod is used for measurement at a measurement point with a high gas concentration, and measurement with a low gas concentration is performed. A large-diameter gas suction pod can be used for measurement at the point, and the trace gas concentration absorbed by a certain amount of the test tube gas absorption liquid falls within the measurement range of the concentration measuring instrument, and air flow suction is repeated. , Or the time for diluting the gas absorbing solution is not required, and efficient tests can be performed.

Further, in the gas suction device of the present invention, the gas suction pod is made of two or more kinds having different inner diameters, and a film-shaped member capable of adjusting the contact angle with the liquid is spread on the inner peripheral surface of the small diameter one. I made it.

As a result, even in a test using gas suction pods having different inner diameters, the liquid level can be kept constant by selecting the film member regardless of the inner diameter size, and an accurate suction amount into the test tube can be set. The test accuracy can be improved.

Further, in the gas suction device of the present invention, the gas suction pod is composed of a plurality of gas suction pods having the same diameter and different lengths, and the lowered internal liquid level reaches the lower end of the gas suction pod having a short length. An automatic opening / closing mechanism for closing the opening is provided.

As a result, the suction speed of the air flow from all the measurement points into the test tube can be made constant, and the suction amount can be set according to the measurement points, so that the test time can be shortened and the test accuracy can be improved.

Further, in the gas suction device of the present invention, the liquid level poured into and discharged from the liquid tank is water or a liquid having a viscosity higher than that of water.

As a result, when water is used as the liquid, the test preparation is simplified, the test cost can be reduced, and when a liquid having a viscosity higher than that of water is used, the pulsation of the pump that changes the liquid level in the liquid tank can be reduced. The amount of intermittent change in the liquid level can be minimized, and the test accuracy can be further improved.

[Brief description of drawings]

FIG. 1 is a side view of a gas suction device showing a first embodiment of the present invention,

FIG. 2 is a side view of a gas suction device showing a second embodiment of the present invention,

FIG. 3 is an enlarged side view of a gas suction pod used in the gas suction device according to the third embodiment of the present invention,

FIG. 4 is a side view of a gas suction device showing a fourth embodiment of the present invention,

FIG. 5 is a side view of a gas suction device showing a fifth embodiment of the present invention,

FIG. 6 is a side view of a gas suction device showing a sixth embodiment of the present invention,

FIG. 7 is a side view showing a wind tunnel and a gas suction device that have been conventionally used to measure a trace gas concentration in an airflow flowing on a terrain model.

[Explanation of symbols]

01 Wind tunnel 02 Chimney model 03 Trace gas 04 Air flow 05 Gas sampling hole 06 Sampling tube 07 Test tube 08 Gas absorbing liquid 09 Pipe 010 Flow path switching mechanism 011, 011a, 011b Pipe 012, 012a, 012b Gas suction pod 013 Water 014a, 014b Piping 015, 015a, 015b Chamber 016, 016a, 016b Piping 017 (roller) Pump 018 Silicon tube 19, 19a, 19b Water tank 20, 20a, 20b Gas suction pod 21 Water 22 Water level 23 Piping 24 Pump 25 Water level 26, 26a, 26b Relief control valve 27 Gas suction pod 27a Tapered portion 28 Float 28a Bottom plate portion 28b Conical portion 29, 291a, 291b Large-diameter gas suction pod 30, 301a, 301b Small-diameter gas suction pod 31, 32 Water Position 33 Small-diameter gas suction pod (with film member) 34 Membrane member 35, 35a, 35b Long gas suction pod 36, 36a, 36b Short gas suction pod 37 Automatic opening / closing mechanism

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takashi Uchino             5-717-1, Fukahori-cho, Nagasaki-shi Mitsubishi Heavy Industries             Business Nagasaki Institute (72) Inventor Isao Kurahashi             5-717-1, Fukahori-cho, Nagasaki-shi Mitsubishi Heavy Industries             Business Nagasaki Institute F-term (reference) 2G052 AA02 AB01 AC02 AC25 AD02                       AD22 AD46 BA03 BA14 CA04                       CA12 DA02 GA21 HC02 HC08                       HC27 JA07 JA09

Claims (7)

[Claims] 1. A trace gas that simulates exhaust gas is emitted from a chimney model installed in a wind tunnel that generates an air flow that simulates the wind in a specific area, and a trace gas that simulates a specific position in the area In order to measure the concentration of trace gas diffused in the air flow flowing through a plurality of measurement points set at predetermined positions, it is provided corresponding to the measurement point where the trace gas concentration is measured from the gas sampling hole provided at the measurement point. In a gas suction device for sucking an air flow into a test tube, two liquid tanks connected by a pipe having a pump capable of transferring a liquid in both directions and allowing the liquid discharged from one to be injected into the other by the operation of the pump. , The open bottom is separated from the bottom of the liquid tank and is installed in the liquid tank, and the closed upper surface is connected with pipes for connecting the test tubes, respectively.
A cylindrical gas suction pod forming a set and the gas suction pod interposed in the pipe and installed in one of the liquid tanks communicated with the test tube and were installed in the other liquid tank. A gas suction device provided with a flow path switching mechanism for communicating the gas suction pod to the atmosphere. 2. The gas suction device according to claim 1, wherein the gas suction pod is provided with a relief control valve at an upper end portion for discharging air flowing into the gas suction pod to the outside. 3. A gas suction pod is provided so as to project upward from an upper end portion, the top end is connected to the pipe, and a taper portion having a conical space formed therein and a vertical movement inside the gas suction pod. 2. The gas according to claim 1, further comprising: a float having a conical portion, which rises / falls according to the liquid level of the fluid and which is fitted to the tapered portion and closes the pipe when the fluid is raised, provided above. Suction device. 4. The gas suction device according to claim 1, wherein the gas suction pod is made of at least two types having different inner diameters. 5. The gas suction pod is made of at least two types having different inner diameters, and a film member capable of adjusting a contact angle with a liquid is spread on the inner peripheral surface of at least the small diameter pod. The gas suction device according to claim 4. 6. The gas suction pod is composed of at least two types having the same diameter and different lengths, and an automatic opening / closing mechanism for closing an opening provided on the bottom surface is provided at the lower end of the short one. The gas suction device according to claim 1, wherein 7. The gas suction device according to claim 1, wherein the liquid is water or a liquid having a viscosity higher than that of water.