JPS591940A - Control for intake of atmospheric air by difference of absolute humidity - Google Patents

Abstract

PURPOSE:To control the intake of atmospheric air most properly by a method wherein the amounts of variations in the absolute humidifies of blow-off air and indoor air are utilized in an air-conditioning equipment. CONSTITUTION:A dew point meter 3, provided at the blow-off port 2 of a room 1, and an atmosphere intake control damper 5, provided in an atmosphere intake duct 4, are connected by an instrument wiring 7 through an operator 6. The absolute humidity of blow-off air upon designing, the absolute humidity at the set indoor temperature, the airflow amount characteristics of the atmosphere intake damper and the air intake of atmosphere upon designing are preset into the operator 6 and the absolute humidity is detected by the dew point meter 3 to change the opening degree of the atmosphere intake damper 5 by the difference of the absolute humidities between the blow-off air and the indoor air and feed atmospheric air by a fan 11.

Description

[Detailed Description of the Invention] The present invention relates to a method for controlling the amount of outside air intake in air conditioning equipment,
In particular, the present invention relates to a method for controlling the amount of outside air intake based on the absolute humidity difference, which controls the amount of outside air intake based on the absolute humidity difference between blown air and indoor air.

Conventional air conditioning equipment has been configured to control the amount of outside air taken in using a carbon dioxide detector attached to the intake port. However, such a configuration has the following drawbacks.

(1) Carbon dioxide detectors are expensive.

(2) Several carbon dioxide detectors are installed near the suction port, so they easily get dirty and must be cleaned thoroughly.

(3) Detectors installed near the inlet tend to take in a large amount of outside air because the carbon dioxide from all the indoor air is combined, and the carbon dioxide concentration is higher than near the center of the space where people are.

The object of the present invention is to overcome the drawbacks of the prior art.

It is inexpensive, does not require much cleaning, and can take in an appropriate amount of outside air. An object of the present invention is to provide a method for controlling the amount of outside air intake based on an absolute humidity difference.

The present invention is designed to control the amount of outside air intake based on the amount of change in the absolute humidity of the blown air and indoor air, after confirming through experiments that there is a strong correlation between the indoor carbon dioxide concentration and the amount of moisture generated. Figure 1 shows the experimental results of the relationship between indoor moisture generation and carbon dioxide concentration.

It can be seen that there is a correlation between the amount of water generated and the carbon dioxide concentration.

The present invention was made based on the results of this experiment.

In other words, the main factors that change the absolute humidity in an indoor environment are humans and leakage air. The absolute humidity of leaked air is considered to be approximately constant, and the amount of leaked air is also approximately constant, so changes in the absolute humidity in the room □ can be considered to be changes in the number of personnel. On the other hand, humans are the main cause of changes in indoor carbon dioxide concentrations.

Therefore, a strong correlation appears between the amount of change in indoor absolute humidity and the amount of change in carbon dioxide concentration.

FIG. 2 shows a system diagram of an embodiment of the method for controlling the amount of outside air intake based on the absolute humidity difference according to the present invention.

Dew point meter 3 installed at air outlet 2 of room 1 and outside air intake system 4
An outside air intake amount control damper 5 installed in the system is connected via an arithmetic unit 6 to an instrumentation wiring 7. Air supply duct8. Return air duct9. Air conditioning equipment 10. Install the blower 11.

The absolute humidity of the blown air at the time of design, the absolute humidity of the indoor set value, the air volume characteristics of the outside air intake damper, and the amount of outside air intake at the time of design are input into the calculator 6 in advance.

Air is supplied by the blower 11 while changing the opening degree of the outside air intake damper 5 depending on the ratio of (absolute air humidity minus indoor setting absolute humidity) (design absolute humidity of air blowing out - absolute indoor setting absolute humidity). This invention has confirmed through experiments that there is a correlation between the indoor carbon dioxide concentration and the amount of moisture generated, and detects absolute humidity with a dew point meter instead of a carbon dioxide detector. Since the outside air is regulated by humans based on the absolute humidity difference between the

[Brief explanation of drawings]

Fig. 1 is a diagram showing the experimental results of the relationship between indoor moisture generation amount and carbon dioxide concentration, and Fig. 2 is a system diagram of an embodiment of the method for controlling the amount of outside air intake based on the absolute humidity difference according to the present invention. It is. 2...Blowout outlet 3...Dew point meter 4...Air intake duct 5...Outside air intake amount control damper 6...Arithmetic unit 7...Instrumentation wiring.

Claims (1)

[Claims] The dew point meter installed at the indoor air outlet and the outside air control damper installed in the outside air intake duct are connected via instrumentation wiring via a computing unit, and the amount of outside air intake is determined based on the difference in absolute humidity between the blown air and the indoor air. How to control.