JPH0258546B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for setting the opening degree of an indoor air outlet in a so-called ductless air conditioning system in which a duct is removed from the ceiling.

<Conventional technology> Ductless air conditioning systems supply conditioned air from a blower to the space in the attic through an outlet in the ceiling, use the space in the attic as an air supply chamber, and supply conditioned air from the indoor outlet installed in the ceiling. It blows out conditioned air into the room. This ductless air conditioning system has the following advantages and is therefore widely used as an air conditioning system for large spaces such as large stores.

Since there is no duct work other than the main duct or insulation work, construction time can be shortened and construction costs can be reduced.

By significantly simplifying the ducts in the ceiling, the dimensions of the bottom end of the beam and the ceiling surface can be reduced compared to conventional duct systems, and the floor height can be reduced.

Since there is no connection between the main duct and the indoor air outlet, the indoor air outlet can be arranged freely. Therefore, flexibility in the design of the ceiling surface is ensured,
It will be easier to respond to remodeling after construction is completed. That is, flexibility in the arrangement of the indoor air outlet can be obtained.

Since the space under the attic is used as an air supply chamber, it is possible to utilize the radiation effect of the ceiling and floor surfaces and the heat storage effect of the floor surface, which has a large heat capacity.

However, in the ductless air conditioning system mentioned above,
For the following reason, the air volume from the indoor air outlet cannot be predicted, and the opening degree of the indoor air outlet must be set by trial and error by actually operating the indoor air outlet, which takes time and effort. There is a problem. That is, as shown in FIGS. 13 and 14, the blower 10
The conditioned air sent from 0 is air outlet 1 in the ceiling.
01, it is blown out into the space 102 in the attic, and convection occurs in the space 102 in the attic as shown by arrows A and B. Then, conditioned air is supplied from the space 102 under the attic to the air-conditioned room 115 through the indoor air outlets 103, 104, 105, and 106. By the way, the direction of flow of conditioned air shown by arrows A and B convecting in the space 102 under the attic, and the indoor air outlet 103,
Arrows X blown out from 104, 105, 106
There is a perpendicular relationship with the direction of air flow shown by arrows A and B, and the air flowing in convection shown by arrows A and B has a direction X of the indoor air outlet 103, 104, 105, and
has no velocity component. Therefore, the amount of air blown from the indoor air outlets 103, 104, 105, 106 is
It is determined by the static pressure difference between the inside and outside of the ceiling. On the other hand, according to Bernoulli's theorem, (dynamic pressure) + (static pressure) = constant, so the static pressure distribution in the space 102 in the attic is determined by the flow velocity distribution of convection in the attic. However, the flow velocity distribution in the attic space is complicated and changes depending on the structure of the attic space, and it changes just by changing the opening degree of one indoor air outlet, so it is difficult to predict in practice.
Therefore, indoor air outlets 103, 104, 10
It is difficult to predict the air volume from 5,106.

For this reason, in the past, the opening degree of the indoor air outlet had to be set by trial and error using the actual machine, as described above, which posed the problem of requiring a lot of man-hours and time. Furthermore, since the amount of air from the indoor air outlet cannot be predicted, there is a problem in that the opening degree of the indoor air outlet cannot be automatically adjusted.

<Object of the Invention> Therefore, an object of the present invention is to enable the opening degree of an indoor air outlet to be accurately set for a desired air volume without trial and error.

<Structure of the Invention> In order to achieve the above object, the present invention uses an air blower and an indoor air outlet as connection points, and assumes a wind path that connects them. Set up the net model,
In addition, by blowing out conditioned air from the in-ceiling outlet to prevent specific convection from occurring in the above-mentioned attic space as much as possible, Kirchhoff's law for electrical circuits can be applied analogously to the above-mentioned ventilation circuit network. , Calculate the airflow volume using Kirchhoff's law from the resistivity corresponding to the assumed opening degree of the indoor air outlet, and set the opening degree of the indoor air outlet by repeating the assumption of resistivity until the desired airflow volume is obtained. Its basic feature is that it is made to do so. More specifically, in the present invention, the in-ceiling outlet is configured such that the conditioned air blown out from the in-ceiling outlet flows uniformly in substantially all directions along the ceiling plane, and the above-mentioned blower and the above-mentioned indoor blower We set up a model of the ventilation network that assumes the outlet as a connection point and a wind duct that connects the connection points. Next, we calculate the target air volume of the wind duct, V ₂ ′, which is the desired air volume from the indoor air outlet.
In addition to setting V ₃ ′, V ₄ ′, and V ₅ ′, set the specific resistance R ₁ , R ₆ , R ₇ , R ₈ , and R ₉ determined by the structure of the building, and then set the specific resistance of the indoor air outlet. Assuming specific resistances R ₂ , R ₃ , R ₄ , and R ₅ of the air duct determined by the degree of opening, next, the pressure drop amount Fi in each mesh forming the closed circuit in the ventilation circuit network is calculated by It is expressed as a function of the flowing air volume Vi and the specific resistance Ri, and assuming that each of the above pressure drop amounts Fi is zero, the air volume V ₂ of the wind duct, which is an unknown quantity,
Calculate V ₃ ,...,V ₉ , then calculate the calculated air volume
V ₂ , V ₃ , V ₄ , V ₅ are the target air volumes V ₂ ′, V ₃ ′, V ₄ ′,
It is determined whether or not V ₅ ' is within a certain tolerance range, and the air volume V ₂ , V ₃ , V ₄ , V ₅ calculated above is determined.
is not within the above-mentioned allowable range,
Specific resistance R ₂ determined by the opening degree of the indoor air outlet,
Assuming R ₃ , R ₄ , and R ₅ again, the air volume of the wind duct V ₂ ,
The calculations for calculating V ₃ , V ₄ , and V ₅ are performed using the calculated air volume.
V ₂ , V ₃ , V ₄ , V ₅ are the target air volumes V ₂ ′, V ₃ ′, V ₄ ′,
Repeat until V ₅ ′ falls within a certain tolerance range.
The opening degree of the indoor air outlet is set from the resistivity R ₂ , R ₃ , R ₄ , R ₅ when the calculated air volume V ₂ , V ₃ , V ₄ , V ₅ falls within the above-mentioned certain tolerance range. It is characterized by the fact that

<Examples> The present invention will be described in detail below with reference to illustrated examples.

In Figure 1, 11 is an air-conditioned room, 12 is a ceiling plane, 13 is an upper slab, 15 is a space under the attic, 1
6 is a beam.

Further, 6 is a blower for supplying conditioned air, 21 is an air supply duct, and 22 is an in-ceiling outlet provided at the tip of the air supply duct 21. This ceiling air outlet 2
2 blows the conditioned air in an upward direction perpendicular to the ceiling plane 12, that is, toward the upper slab 13,
The rebounded air is made to flow uniformly in substantially all directions along the ceiling plane 12. The specific structure of this in-ceiling outlet (hereinafter referred to as a fountain-type in-ceiling outlet) 22 is as shown in FIG.
Conditioned air is gradually blown upward evenly from the entire surface of the perforated plate 201 through the plurality of holes 202, 202, .

In addition, 1, 2, 3, and 4 are indoor air outlets provided in the ceiling plane 12 (indoor air outlets 3 and 4 are indoor air outlets 1,
2, it is located far away from the paper. ), 5 is a return port.

Next, the blower 6 and the indoor air outlets 1, 2,
3 and 4 as connection points, a model of the ventilation circuit network as shown in FIGS. 3 and 4 is set up. As shown by the lines in Figures 3 and 4, each connection point 1, 2,
Assume a wind path connecting 3, 4, and 6. This air passage is assumed to be an air path that passes under a beam, through an indoor air outlet, etc.

In Fig. 4, V ₁ to _{V 9} are the air volume (m ³ /s) flowing through each air duct, and R ₁ to R ₉ are the specific resistance (Kgf・
s ² /m ⁸ ), and q ₂ to _{q 5} are the air volume (m ³ /s) of each mesh (closed circuit in the ventilation network). The above specific resistance R ₁ is the resistance of the air supply duct 21, and the specific resistance R ₆ , R ₇ ,
R ₈ and R ₉ are determined by the structure of the attic space, such as the dimensions under the beams 16 and 16 in the attic space 15, and the specific resistances R ₂ , R ₃ , R ₄ , and R ₅ are mainly determined by the indoor It is determined by the opening degree of the air outlets 1, 4, 3, and 2. On the other hand, the relationship between the dimension under the beam and the local resistance in the attic space 15 is as shown in Figure 5, and by adding the specific resistance of the walls in the ceiling to the local resistivity under the beam found from this, the ceiling is determined. The specific resistances R ₆ , R ₇ , R ₈ , and R ₉ of the air ducts in the back space are determined. Also,
From the graph in Figure 6 showing the opening degree and pressure loss of indoor air outlets 1, 2, 3, 4, indoor air outlets 1, 2, 3,
The specific resistance for the opening degree of 4 is determined, and by adding the known specific resistance of the return port 5 and the air passage in the air-conditioned room 11 to this value, the air duct downstream of the indoor air outlet 1, 4, 3, and 2 is calculated. The specific resistances R ₂ , R ₃ , R ₄ , and R ₅ are determined. Therefore, the specific resistances R ₂ , R ₃ , R ₄ , and R ₅ are uniquely determined with respect to the opening degrees of the indoor air outlets 1, 4, 3, and 2.

Now, the following equation holds true for the air volumes V ₁ to V ₉ and the air volumes q ₁ to _{q 5} of the mesh.

V ₁ = q ₁ , V ₂ = q ₁ − q ₂ , V ₃ = q ₂ − _{q 3} V ₄ = q ₃ − q ₄ , V ₅ = q ₄ , V ₆ = q ₂ − q ₅ V ₇ = q ₅ , _V8 = _q5 - _q4 , _V9 = _q3 - _q5 ... (1) On the other hand, the pressure loss h when the unit air volume passes in the unit time is h = R· ^V2 .

h: Pressure loss (mmAq or Kgf/m ² ) V: Air volume (m ³ /s) R: Specific resistance (Kgf・s ² /m ⁸ ) Therefore, for each mesh, air flows in the direction of the arrow in Figure 4. flows, and the amount of pressure drop in the process (F)
The following equation holds true as functions F ₁ to F ₅ .

F ₁ = R ₁・V ₁・|V ₁ |+R ₂・V ₂・|V ₂ |−Pf F ₁ =R ₁・V ₁・|V ₁ |+R ₂・V ₂・|V ₂ |−Pf F ₂ = −R ₂・V ₂・｜V ₂ ｜＋R ₆・V ₆・｜V ₆ ｜＋R ₃・V ₃・｜V ₃
| F ₁ = R ₁・V ₁・|V ₁ |+R ₂・V ₂・|V ₂ |−Pf F ₂ =−R ₂・V ₂・|V ₂ |+R ₆・V ₆・|V ₆ | +R ₃・V ₃・｜V ₃
｜ F ₃ = −R ₃・V ₃・｜V ₃ ｜+R ₉・V ₉・｜V ₉ ｜+R ₄・V ₄・｜V ₄
| F ₁ = R ₁・V ₁・|V ₁ |+R ₂・V ₂・|V ₂ |−Pf F ₂ =−R ₂・V ₂・|V ₂ |+R ₆・V ₆・|V ₆ | +R ₃・V ₃・｜V ₃
｜ F ₃ = −R ₃・V ₃・｜V ₃ ｜+R ₉・V ₉・｜V ₉ ｜+R ₄・V ₄・｜V ₄
｜ F ₄ = −R ₄・V ₄・｜V ₄ ｜−R ₈・V ₈・｜V ₈ ｜＋R ₅・V ₅・｜V ₅
| F ₁ = R ₁・V ₁・|V ₁ |+R ₂・V ₂・|V ₂ |−Pf F ₂ =−R ₂・V ₂・|V ₂ |+R ₆・V ₆・|V ₆ | +R ₃・V ₃・｜V ₃
｜ F ₃ = −R ₃・V ₃・｜V ₃ ｜+R ₉・V ₉・｜V ₉ ｜+R ₄・V ₄・｜V ₄
｜ F ₄ = −R ₄・V ₄・｜V ₄ ｜−R ₈・V ₈・｜V ₈ ｜＋R ₅・V ₅・｜V ₅
｜ F ₅ = −R ₆・V ₆・｜V ₆ ｜+R ₇・V ₇・｜V ₇ ｜+R ₈・V ₈・｜V ₈
｜−R ₉・V ₉・｜V ₉ ｜……(2) Since each mesh constitutes a closed circuit,
F ₁ =F ₂ =...=F ₅ =0. Note that Pf is the discharge pressure of the blower.

From the above equations (1) and (2), if the specific resistances R ₁ to R ₉ are set, the air volumes V ₁ to _{V 9} can be determined. Based on this, the computer sets the opening degrees of the indoor air outlets 1, 2, 3, and 4 as shown in FIG.

First, in step S ₁ , the known air volume V ₁ of the blower 6 and the target air volume of the indoor air outlets 1, 4, 3, and 2 are determined.
V ₂ ′, V ₃ ′, V ₄ ′, V ₅ ′, known attic space 15
The specific resistance R ₆ to R ₉ of the air duct and the specific resistance R ₁ of the air duct including the air supply duct 21 and the attic space 15 are input.

Next, proceed to step _S2 and open the indoor air outlet 1,
Assume specific resistances R ₂ to R ₅ of 4,3,2.

Next _, proceeding to steps _{S 3 and} S ₄ , _the air volume _{V 2} to V Calculate ₉ .

Next, the process proceeds to step _S5 , where the previously calculated air volume from the indoor air outlets 1, 4, 3, and 2 is calculated from V ₂ to _{V 5 .}
is within the allowable range, that is, |Vi−Vi′|/Vi≦0.01, with respect to the target air volume V ₂ ′ to _{V 5} ′. If it is within the allowable range, the The opening degrees of the indoor air outlets 1, 4, 3, and 2 are determined from the specific resistances R ₂ to R ₅ assumed to be appropriate values. On the other hand, the calculated blowout air volume V ₂ ~ _{V 5} is the target air volume V ₂ ′ ~
If it is not within the tolerance range for V ₅ ′,
Proceed to step _S6 .

In step _S6 , the previously assumed specific resistances _R2 to _R5 are determined to be inappropriate, and new specific resistances _R2 to _R5 are set using the following equations, and the process returns to step _S3 .

Ri←Ri×√′ In this way, the air volume V ₂ ~ V ₅ calculated by applying Kirchhoff's law without convection is compared with the target air volume V ₂ ′ ~ V ₅ ′ to reach the desired air volume. until it becomes
Opening degree of indoor air outlet (i.e. specific resistance of air outlet)
By changing and setting , it is possible to easily and accurately determine the optimal opening degree of the indoor air outlet without relying on trial and error using the actual machine.

The ventilation circuit network shown in Figures 1, 3, and 4 is as follows:
Although the case is shown in which the conditioned air coming out of the blower 6 returns directly to the blower 6 via the attic space 15 and the conditioned room 11, the present invention is not limited to this, and the air in the conditioned room 11 is When going outdoors, the blower 6 sucks in that amount of outdoor air and sends it to the attic space 15. Figures 3 and 4 show the ventilation circuit network in this case. Become.

Figures 8 and 9 show a first experimental example set up using the method of the present invention. In this experimental example, a fountain-type ceiling air outlet 6 shown in FIG. 2 is used as the ceiling air outlet, and there is a beam in the attic space.

As can be seen from the arrows indicating the wind direction in Figure 8, no convection is occurring in the attic space. Furthermore, as can be seen from FIG. 9, the calculated values of air volume enclosed in parentheses and the measured values of air volume not enclosed in parentheses are in good agreement. This is considered to be because no convection is occurring in the attic space 15.

Figures 10 and 11 show the second
An experimental example is shown. In this experimental example, a fan-shaped or diffused-type in-ceiling outlet 35 shown in Fig. 12 that blows out conditioned air in all directions parallel to the ceiling plane is used as the in-ceiling outlet, and there is a beam in the ceiling space. , and there are obstacles 36 that are not air-conditioned, such as elevators.

FIG. 10 shows the static pressure distribution in the attic space, and it can be seen that the static pressure is uniformly and entirely lowered from the in-ceiling air outlet 35, and no convection is occurring. Furthermore, from FIG. 11, it can be seen that the measured values and calculated values agree well.

<Effects of the Invention> As is clear from the above, this invention prevents convection from occurring in the space behind the ceiling, assumes a ventilation network, and calculates the indoor air outlet using Kirchhoff's law. By comparing the air volume of The optimal opening degree of the indoor air outlet can be easily and accurately set. In addition, since the air volume from the indoor air outlet can be predicted, in a ductless air conditioning system, the blower discharge volume and the opening degree of the indoor air outlet can be adjusted according to changes in the indoor heat load or seasonal changes. Automatic adjustment can be made accordingly.

[Brief explanation of drawings]

Fig. 1 is a sectional view of one embodiment of the present invention;
Figure 12 is a perspective view of the air outlet in the ceiling, 3rd and 4th figures.
The figure shows the ventilation circuit network, Figures 5 and 6 show the resistance under the beam and characteristics of the indoor air outlet, Figure 7 shows the flowchart, and Figures 8, 9, 10, and 11 show the experimental data. 13 and 14 are a longitudinal sectional view and a horizontal sectional view of a conventional example. 1, 2, 3, 4...Indoor air outlet, 6...Blower, 11...Air conditioned room, 15...Space in the attic,
22, 35...In-ceiling air outlet.

Claims (1)

[Scope of Claims] 1. Conditioned air from a blower is supplied to the space in the attic from an outlet in the ceiling, the space in the attic is used as an air supply chamber, and the conditioned air is supplied to the air-conditioned room from a plurality of indoor outlets attached to the ceiling. In a ductless air conditioning system that supplies conditioned air to A model of the ventilation circuit network is set up assuming a wind duct that connects the connection points with the above indoor air outlet as the connection point, and then a target air volume of the wind duct that is the desired air volume from the indoor air outlet is set. In addition to setting V ₂ ′, V ₃ ′, V ₄ ′, and V ₅ ′, the specific resistances R ₁ , R ₆ , and
Set R ₇ , R ₈ , R ₉ , then assume the specific resistance of the air passage determined by the opening degree of the indoor air outlet R ₂ , R ₃ , R ₄ , R ₅ , and then The amount of pressure drop Fi in each mesh forming a closed circuit in the circuit network is expressed as a function of the air volume Vi flowing through the air duct and the specific resistance Ri, and assuming each pressure drop amount Fi is zero, the air volume V ₂ of the air duct, which is an unknown quantity, is , V ₃ , ..., V ₉ are calculated, and then the calculated air volumes V ₂ , V ₃ , V ₄ , V ₅ are compared to the target air volumes V ₂ ′, V ₃ ′, V ₄ ′, V ₅ ′. If the air volume V ₂ , V ₃ , V ₄ , V ₅ calculated above is not within the certain allowable range, the indoor air outlet is Assuming _{again the} specific resistances _{R 2} , R ₃ , R ₄ , and _{R 5 corresponding} to the opening degrees of V ₂ , V ₃ , V ₄ , and V ₅ are the target air volume V ₂ ′,
Repeat until V ₃ ′, V ₄ ′, and V ₅ ′ are within a certain tolerance range, and calculate the ratio when the calculated air volume V ₂ , V ₃ , V ₄ , and V ₅ are within the above-mentioned tolerance range. Resistance R ₂ ,
A method for setting the opening degree of an indoor air outlet in a ductless air conditioning system, characterized in that the opening degree of the indoor air outlet is set from R ₃ , R ₄ , and R ₅ . 2 The in-ceiling outlet is oriented in a direction perpendicular to the ceiling plane, and after the air blown out from the in-ceiling outlet collides with the slab or ceiling surface, it flows uniformly in substantially all directions along the ceiling plane. A method for setting the opening degree of an indoor air outlet in a ductless air conditioning system according to claim 1.