JPS5879696A - Air flow control method - Google Patents

Abstract

PURPOSE:To control the air conditioning smoothly by operating a damper and controlling the air flow when the air condition has departed from the setting band of constant width around the setting. CONSTITUTION:Motor dampers 9, 10, 11 for controlling the outer air, return air and the exhaust are provided on an outer air duct 1, return duct 3 and an exhaust duct 2. Then the outer air condition is detected by an outer air condition detecting sensor 12 and compared with the setting by means of a setter 13 and when the outer air condition will increase, it is varied c d2 e1 f, while when it will drop, it is varied f e2 d1 c, thus to reduce the operating frequency of the dampers 9-11. consequently the condition of the mixed air will be vary smooth.

Description

[Detailed Description of the Invention] This invention relates to a method for controlling the air volume of air conditioning equipment in factories, department stores, computer rooms, etc., and in particular to a method for controlling the air volume of air conditioning equipment in factories, department stores, computer rooms, etc. The present invention relates to a method of controlling air volume according to Dan/Abo.

FIG. 1 shows the relationship between outside air conditions and changes in air volume, with the enthalpy of outside air expressed on the horizontal axis. Figure 2 shows the psychrometric diagram. Fig. fa1 and Fig. 2 show the correspondence between the change in air volume and the change in the state of the air when outside air is taken in.

Conventionally, when using outside air for cooling, the outside air condition W
4 (temperature, humidity, enthalpy, etc.) are constantly changing.

In the general outside air intake method, the minimum amount of outside air is taken in in the Zz zone, the appropriate amount is taken in in the z2 zone, the maximum amount is taken in in the zs zone, and the minimum amount is taken in in the Z4 zone.

Here, as shown by the arrow in Figure 2, when the outside air condition exceeds the set value R#, the damper changes from the minimum opening to the maximum opening, or vice versa, from the maximum opening to the minimum opening. Then, as shown in FIG. 1, the air volume is changed by de or θ→(lK).

When the outside air conditions change from moment to moment and go up and down as shown by the arrows in Figure 2, when it gets really hot, the air volume also changes from maximum to minimum or vice versa, which is undesirable because hunting occurs in air conditioning control. .

SUMMARY OF THE INVENTION An object of the present invention is to provide an air volume control method that eliminates the drawbacks of the prior art described above, eliminates hunting due to damping and ξ, and smoothly performs air conditioning control.

In this invention, instead of a set value for the state of the air passing through the damper, a set band having a constant width is set around this set value, and when the air condition goes out of the range of this set band, It is configured to control the air volume by operating a damper.

FIG. 3 shows the relationship between the outside air condition and the change in air volume in the air volume control method according to the present invention.

As shown in FIG. 3, this invention changes the setting of the switching point of the damper when the outside air condition rises and when it falls, and controls it with a width of Δt as a means to prevent control hunting. It is something.

Therefore, when the outside air condition (for example, en, tarbi) increases, the change is made from C→d2→θl−f in FIG.
Conversely, when descending, the frequency of opening and closing of the damper is reduced by changing f→θ2−(11→C).

FIG. 41 is a system diagram showing an example of air conditioning equipment to which the air volume control method according to the present invention is applied.

Outside air flows in from outside air duct 1, part of the exhaust air flows out from exhaust duct 2, is branched into return air duct 3, and is recirculated.After being mixed with return air in supply air duct 4, it is sent to the air conditioner. 5 and is sent to an air conditioning room 7 by a blower 6.

Exhaust air is discharged by an exhaust fan 8 through an exhaust duct 2.

An electric damper 9 for external air control is attached to the inlet of the outdoor air duct 1, an electric damper 10 for internal air control is attached to the return air duct 3, and an electric damper ξ11 for exhaust control is attached to the outlet of the exhaust duct 2.

The outside air condition is detected by the outside air condition detection sensor 12 attached to the inlet of the outside air tally 1, and compared with the value set by the setting device 13, the electric damper is controlled by the controller 14 so as to change as shown in FIG. 9.10 and 11 are controlled. By performing such control, the air supply duct 4
This is to stabilize the air condition inside the air conditioning room 7 and at the entrance of the air conditioning room 7.

FIG. 5 shows the relationship between the outside air condition and the change in air volume in another embodiment of the present invention.

In the embodiment described above, the damper is controlled using the enthalpy of the outside air, but in the embodiment shown in FIG. 5, the damper is controlled using the dry bulb temperature of the outside air.

According to this embodiment, it can be applied to outside air control that does not require air humidity control, and the effect of outside air cooling is improved.

Although the detailed description of this invention is based on a case where a constant state of air is created by taking in outside air and mixing it with other air, it is of course applicable to other similar cases.

In this invention, instead of a set value for the state of the air passing through the damper, a set band having a constant width is set around the set value, and when the air condition goes out of the range of this set band, the damper is damped.・Since the air volume is controlled by manipulating ξ, the frequency of damper operation is reduced, resulting in the effect of smoother changes in the state of the mixed air.

Figure 6 (4) shows the state of mixed air in the conventional system, Figure 6 (B
) shows the state of mixed air according to the air volume control method of the present invention, and is a smooth curve.

[Brief explanation of the drawing]

FIG. 1 shows the relationship between outside air conditions and changes in air volume in the conventional method, FIG. 2 shows an psychrometric diagram, FIG. 3 shows the relationship between outside air conditions and changes in air volume in the AT control method according to the present invention, and FIG. The figure is a system diagram showing an example of air conditioning equipment to which the air volume control method according to the present invention is applied. Condition of mixed air according to the conventional method FIG. 6(B) shows the condition of mixed air according to the air volume control method according to the present invention. ■...Outside air duct, 2...Exhaust, duct,
S3...Return air duct, 4...Air supply duct,
5...Air conditioner, 7...Air conditioning room, 9
...Electric damper for outside air control, 10...Electric damper for return air control, 11...Electric damper ξ for exhaust control, l2...Sensor for detecting outside air condition, 13...Setting device, 14 ...Controller.

Claims (1)

[Claims] (1) In an air volume control method for controlling air volume attached to a duct system of air conditioning equipment or an air conditioner, the damper is operated based on a set value for the state of air passing through the damper, the set value for the air condition. Instead, a set band having a certain width is set around the set value, and when the air condition falls outside of this set band, the damper is operated to control the air volume. A method of controlling the air volume.