JP2003042506A - Method and system for evaluating ventilation performance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and system for evaluating ventilation performance by which ventilation performance can be evaluated extremely easily and appropriately. SOLUTION: A plurality of ethanol concentration sensors 4 are set up in a space 2 to be evaluated for ventilation performance. An air supply system 10 is connected to an air supplying opening 6 provided in the lower part of the space 2, and the ethanol vapor generated by means of an ethanol vapor generating device 12 is sent to the space 2 from the air supplying opening 6 through the air supply system 10. Each sensor 4 measures the ethanol concentration in the air in real time and outputs the measured results to an accumulating computer system 14. The system 14 forms the state of ventilation in the space 2 one after another by analyzing the measured results and expressing the state of ventilation in the forms of graphs, tables, distribution charts, etc., based on the state of ventilation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and system for evaluating ventilation performance in an indoor space or the like, and more particularly to a technique for appropriately evaluating ventilation performance with a very simple method.

[0002]

2. Description of the Related Art In recent years, health problems caused by indoor chemical substances such as sick buildings, sick houses, and chemical hypersensitivity have become a problem, and the interest in indoor air quality is increasing. In order to improve the indoor air quality, it is necessary to take measures against pollutant sources such as building materials, finishing materials, interior materials, etc., and to properly understand the proper ventilation performance and appropriately improve indoor ventilation. is important. Conventionally, there have been the following methods for evaluating ventilation performance.

1) Step-up method Ventilation performance is evaluated. A tracer gas having a known concentration is mixed into the space to be evaluated through an air supply port, and the time-dependent change in the tracer gas concentration at the exhaust port is measured to raise the tracer gas concentration. The average ventilation performance in the evaluation target space is evaluated based on the characteristics.

2) Step-down method Ventilation performance is evaluated. When tracer gas is mixed and agitated so as to have a constant known concentration in the space to be evaluated, and when air supply is started, the time-dependent change in tracer gas concentration at the exhaust port. Is measured, and the average ventilation performance in the evaluation target space is evaluated based on the falling characteristics of the tracer gas concentration.

3) Pulse Method Ventilation Performance Evaluation When a tracer gas of known concentration is mixed in a pulse shape into the space to be evaluated from the air supply port, the time change of the concentration at the exhaust port is measured, and the tracer gas is measured. The average ventilation performance in the evaluation target space is evaluated from the rising and falling characteristics of the concentration.

[0006]

However, in these evaluation methods, toxic, suffocating and flammable gases such as sulfur hexafluoride, nitrous oxide, ethane and methane are used as tracer gas. Therefore, there was a problem that it was very difficult to handle at the actual site.
Further, in measuring the concentrations of these gases, samples must be taken at regular intervals and analyzed individually for each sample. In that analysis, GC (GasChromatograp
Since it is necessary to use an analyzer such as h) or IGA (Infrared Gas Analyzer), it takes a great deal of time, labor and cost. Moreover, only the average ventilation performance could be evaluated, and it was very difficult to investigate even the distribution of ventilation performance (stagnation and short path).

[0007] The present invention has been made in view of the above circumstances, and its purpose is to provide excellent on-site handleability, to save a great deal of labor and labor for analysis, and to improve ventilation performance. It is to provide a ventilation performance evaluation method and system that can be appropriately evaluated by a very simple method.

[0008]

In order to achieve such an object, in the ventilation performance evaluation method according to the present invention, a tracer gas is fed into the evaluation space for evaluating the ventilation performance, and the evaluation space is evaluated. The concentration of the tracer gas contained in the air inside or the air discharged from the exhaust port of the evaluation target space is measured, and data for evaluating the ventilation performance in the evaluation target space is obtained based on the measurement result. In the ventilation performance evaluation method, ethanol vapor is used as the tracer gas (claim 1).

[0009] Here, ethanol is less contained in the general environment except for hospitals, pharmaceuticals, breweries, etc., has a specific gravity close to that of air, is highly responsive to airflow, and is highly adsorbed on the wall surface. Has characteristics such as
Satisfy the conditions as tracer gas sufficiently. Moreover, it has almost no toxicity, suffocation, or flammability, has less effect on the human body than conventional sulfur hexafluoride, nitrous oxide, ethane, methane, etc., and is very easy to handle. Moreover, it can be easily vaporized by natural evaporation or ultrasonic vibration, and vapor can be easily generated.

In the ventilation performance evaluation method according to the present invention, by using such ethanol vapor as the tracer gas, it is possible to perform the measurement extremely safely and smoothly at the site. Ventilation performance in etc. can be evaluated very easily.

Further, in the ventilation performance evaluation system according to the present invention, an ethanol vapor generator for generating ethanol vapor to be sent into the evaluation target space for evaluating the ventilation performance and the ethanol vapor generation device installed in the evaluation target space or near the exhaust port. The ethanol concentration sensor for measuring the concentration of ethanol contained in the air in the evaluation target space or the air discharged from the exhaust port of the evaluation target space, and the measurement result obtained from the ethanol concentration sensor And a computer device that creates data for evaluating the ventilation performance of the evaluation target space based on the above (claim 2).

Even in this system, the use of ethanol vapor as the tracer gas enables extremely safe and smooth measurement at the site, which makes the ventilation performance in the indoor space very simple. Can be evaluated.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a ventilation performance evaluation method and system according to the present invention will be described below with reference to the accompanying drawings.

The ventilation performance evaluation method according to the present invention uses ethanol vapor as a tracer gas for evaluating ventilation performance. This ethanol vapor is less contained in the general environment except for hospitals, pharmaceuticals, breweries, etc., and more toxic than sulfur hexafluoride, nitrous oxide, ethane, methane, etc. that have been used as tracer gas. It has excellent characteristics such as low suffocation and low impact on the human body, and also has low flammability, which is an advantage that it is much easier to handle than the aforementioned gases. Also, ethanol vapor
Its specific gravity is close to that of air, its ability to follow the air flow is high, and its adsorption to the wall surface is extremely small, which makes it fully applicable as a tracer gas.

Ethanol vapor is applied to various conventional ventilation performance evaluation methods using tracer gas, for example, the above-mentioned step-up method, step-down method, pulse method and the like. That is, ethanol vapor is sent to the evaluation target space for evaluating ventilation performance, the concentration in the air in the evaluation target space or in the air discharged from the exhaust port of the evaluation target space is measured, and the measurement result is Based on this, data for evaluating the ventilation performance in the evaluation target space is created.

By using such ethanol vapor as the tracer gas, the measurement can be performed very safely and smoothly at the site, and therefore the ventilation performance in the indoor space can be evaluated very easily. it can.

Further, the ventilation performance evaluation system according to the present invention includes an ethanol vapor generator for generating ethanol vapor to be sent into the evaluation target space for evaluating ventilation performance, and air in the evaluation target space or exhaust gas of the evaluation target space. An ethanol concentration sensor that measures the concentration of ethanol contained in the air discharged from the mouth, and data for evaluating the ventilation performance of the evaluation target space based on the measurement results obtained from this ethanol concentration sensor are obtained. It is a system provided with a computer device to be created.

The ethanol vapor generation device vaporizes liquid ethanol by a method such as ultrasonic vibration to generate ethanol vapor. This device is installed, for example, in the vicinity of the air supply port in the evaluation target space for evaluating the ventilation performance, or in the air supply port or air supply system of the evaluation target space.

The ethanol concentration sensor measures the concentration of the ethanol vapor thus fed into the space to be evaluated at various places. The ethanol concentration sensor is installed in each place in the evaluation target space or in the vicinity of its exhaust port, and measures the concentration of ethanol contained in the air in the evaluation target space or the air discharged from the exhaust port of the evaluation target space. To do. Then, the measurement result is output to a computer device that collects and analyzes the measurement result.

Especially for this ethanol concentration sensor, it is preferable to use a semiconductor sensor. This semiconductor sensor was recently developed due to the progress of semiconductor technology in recent years.It has excellent reproducibility and responsiveness, enables real-time measurement and continuous measurement, and has extremely high performance and high ethanol concentration. It can be detected accurately. Also, since this semiconductor sensor is small and lightweight,
It is possible to perform on-site measurement very easily. Compared with the conventional method, the labor and cost of the concentration analysis can be dramatically reduced, and it is possible to measure and evaluate ventilation performance in the field and evaluate the distribution state of ventilation performance, which was difficult until now.

Regarding the method for measuring the ethanol concentration using this ethanol concentration sensor, a plurality of sensors may be prepared and each measurement point set in the space to be evaluated may be set to measure the concentration at the same time. The concentration may be measured at a plurality of measurement points while moving one sensor over a plurality of locations.

On the other hand, the computer device is easy for the user to understand based on the measurement results obtained from the ethanol concentration sensor, data for evaluating the ventilation performance of the space to be evaluated, such as tables, graphs and distribution charts. Create data to inform in shape. The computer device is configured by a personal computer or the like. The computer device sequentially acquires the measurement results from the ethanol concentration sensor and collectively collects them in real time. This makes it possible to evaluate the distribution state of ventilation performance, which was difficult until now. The computer device is loaded with a computer program that implements these.

FIG. 1 shows an embodiment of a ventilation performance evaluation system according to the present invention. In this system, a plurality of ethanol concentration sensors 4 are installed in the evaluation target space 2 defined in a rectangular parallelepiped shape. The ethanol concentration sensors 4 are installed at intervals from each other, and measure the concentration of ethanol vapor in air at each location of the evaluation target space 2 individually.

An air supply port 6 (on the left side in the figure) is provided in the lower part of the space 2 to be evaluated, and an exhaust port 8 (on the right side in the figure) is provided in the upper part. An ethanol vapor generation device 12 is connected in the middle of an air supply system 10 that sends external air into the evaluation target space 2 through the air supply port 6.
The ethanol vapor generation device 12 sends the generated ethanol vapor to the air supply system 10 and the air supply port 6 into the evaluation target space 2 via the air supply system 10. The ethanol vapor sent into the evaluation target space 2 is diffused in the evaluation target space 2 and detected by the ethanol concentration sensor 4. The measurement results of each ethanol concentration sensor 4 are sequentially output to the computer device 14 in real time, analyzed by the computer device 14, and the evaluation target space 2
The ventilation status inside is informed in real time by the computer device 14. The ethanol concentration sensor 4 may be installed near the exhaust port 8 to measure the ethanol concentration contained in the air discharged to the outside through the exhaust port 8.

FIG. 2 is a system configuration diagram showing an embodiment of the semiconductor sensor 20. This semiconductor sensor 20
Is a device driven by a commercially available battery 22 mounted inside, and includes a temperature sensor 24, a semiconductor sensor element 26,
A sensor module 30 including a heater 28,
A measurement control microcomputer 32, a crystal oscillator 21, a liquid crystal display unit 34, a mode switching switch module 36,
Vref module 38 and RS232C driver 40
, RS232C / USB conversion module 42, RS
And a 485 driver 44. The ethanol concentration is detected by the semiconductor sensor element 26. Temperature sensor 24
The sensor output from the semiconductor sensor element 26 is input to the measurement control microcomputer 32 through the A / D converters 46 and 48. And the sensor output is RS232C.
As RS232C signal through driver 40 and R
USB via S232C / USB conversion module 42
RS as a signal and via the RS485 driver 44
It is output as a 485 signal to the counting computer device 14. The heater 28 is drive-controlled by the measurement control microcomputer 32 via the PWM module 50. On the liquid crystal display unit 34, various information such as the measurement result of the ethanol concentration and the measurement status are displayed on the screen.

FIG. 3 shows this semiconductor sensor (Developed).
It is the result of examining the detectable range and its linearity by comparison with the detector tube. The detection range of the detector tube for comparison is 0.05
Since it was in the range of 0.5% to 0.5%, only data in that range was obtained, but it was found that with the semiconductor sensor (Developed), sufficient linearity is obtained in this concentration range. On the other hand, the result of another commercially available ethanol concentration sensor (Commercial) also shown in FIG. 3 could not detect the low concentration range. It can be seen that the semiconductor sensor has better measurement capability than other ethanol concentration sensors.

FIG. 4 shows the response characteristics of the semiconductor sensor (Developed). With the semiconductor sensor, a response characteristic within 500 ms was obtained with respect to the rising of the concentration, but it was found that there was a time delay of about 20 seconds with respect to the falling. It is considered that this is due to the evaporation time of ethanol adhering to the surface of the sensor element. From this, it seems that this semiconductor sensor is suitable for use in the step-up method.

[0028]

EFFECTS OF THE INVENTION According to the ventilation performance evaluation method and system of the present invention, ethanol vapor is used as the tracer gas, so that it can be compared with conventionally used sulfur hexafluoride, nitrous oxide, ethane, methane, etc. It has excellent characteristics such as low toxicity and suffocation, and very little effect on human body, and also has low flammability, which is very easy to handle compared with the above-mentioned gases. . In addition, ethanol vapor has characteristics such as a specific gravity close to that of air, high followability to airflow, and very little adsorption on the wall surface, and it is sufficiently satisfied as a tracer gas. . By using such ethanol vapor as the tracer gas, the ventilation performance can be investigated very safely in the actual field (Claims 1 and 2).

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing an embodiment of a ventilation performance evaluation system according to the present invention.

FIG. 2 is a system configuration diagram showing an embodiment of an ethanol concentration sensor used in the ventilation performance evaluation method or system according to the present invention.

FIG. 3 is a graph showing a detectable range of an example of an ethanol concentration sensor used in the ventilation performance evaluation method or system according to the present invention.

FIG. 4 is a graph showing a response characteristic of an example of an ethanol concentration sensor used in the ventilation performance evaluation method or system according to the present invention.

[Explanation of symbols]

2 Evaluation target space 4 Ethanol concentration sensor 6 Air supply port 8 exhaust port 10 Air supply system 12 Ethanol vapor generator 14 Computation computer device

Claims (2)

[Claims] 1. A tracer gas is fed into an evaluation target space for evaluating ventilation performance, and the concentration of the tracer gas contained in the air in the evaluation target space or the air discharged from the exhaust port of the evaluation target space is measured. Then, in the ventilation performance evaluation method for obtaining the data for evaluating the ventilation performance in the evaluation target space based on the measurement result, an ethanol vapor is used as the tracer gas. 2. An ethanol vapor generation device for generating ethanol vapor to be fed into the evaluation target space for evaluating ventilation performance, and an air in the evaluation target space or the evaluation target installed in the evaluation target space or near the exhaust port. An ethanol concentration sensor that measures the concentration of ethanol contained in the air discharged from the exhaust port of the space, and to obtain the measurement results from this ethanol concentration sensor and evaluate the ventilation performance of the evaluation space based on the measurement results. A ventilation performance evaluation system, comprising: