JP2000297960A - Duct for air conditioning piping - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance energy saving performance by constituting a tubular body of a heat insulating material internally having an air layer and a reinforcing body and covering the surface and rear surface of the tubular body with a sealing material thereby reducing heat loss from a duct. SOLUTION: A heat insulating material 21 is wound spirally in two layers and a reinforcing body 22 is wound spirally in the spiral gap of the heat insulating material 21 in order to ensure the strength of a duct. Inner and outer surfaces of a pipe wall constituted of the heat insulating material 21 and the reinforcing body 22 are covered with a sealing material 23 in order to isolate the inside and outside of the pipe from each other. The heat insulating material 21 is subjected to spot facing on the entire surfaces touching each other and an air layer 24 is formed. Preferably, the material of the heat insulating material 21 has low thermal conductivity and a foamed polyethylene is employed, for example. Preferably, the material of the reinforcing body 22 has such a strength as allowing bending but not allowing flexing and hard polyvinyl chloride is employed, for example. A soft vinyl tape is employed, for example, as the sealing material 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a duct. In particular, it relates to a heat insulating / muffling duct connected to a ventilation air conditioner.

[0002]

2. Description of the Related Art In recent years, highly airtight and highly insulated houses have become widespread in order to enhance the energy conservation of houses. In this highly airtight and highly insulated house, the high insulation
There is a case where a house is cooled or heated by a time cooling / heating / ventilation system. That is, as shown in FIG.
A ventilation air conditioner 3 is installed in the attic 2 of the house, and a ventilation duct 4 is provided from the ventilation air conditioner 3 to the attic 2
The pipes are piped to the floor behind the floor 6 and the like, fresh air and cooled / heated air are sent to each room, and the contaminated air returns to the ventilation air conditioner 3 again by the collection duct 7 and is exhausted outside the house.

As shown in FIG. 4, the ventilation air conditioner 3 includes a ventilation air supply fan 106, a ventilation exhaust fan 107, an indoor circulation ventilation fan 108, a total heat exchanger 109, and a cooling / heating heat exchanger 110. And fresh air is supplied to the outside air inlet 102.
Through a total heat exchanger 109 for exchanging heat with exhaust air, further cooled or heated by a cooling / heating heat exchanger 110, and by a ventilation duct 4 via a branch chamber 112. Supply air to each room. At this time, the fresh air that has passed through the total heat exchanger 109 is
The circulating air inlet 1 by the indoor circulating fan 108
The mixture is mixed with the circulating air coming from the air conditioner 05 and passes through the heat exchanger 110 for cooling and heating. The contaminated air supplied to the room is returned from each room to the exhaust inlet 103 via the collection duct 7 by the ventilation exhaust fan 107, and is discharged from the exhaust outlet 101 to the outside of the house through the total heat exchanger 109.

[0004] In the whole building cooling / heating / ventilating system using the ventilation duct and the collection duct, a certain amount of fresh air can be reliably sent to each room in the house by the ventilation duct, and the fresh air is Since heat is recovered by the total heat exchanger in the ventilation air conditioner from the contaminated air recovered by the recovery duct, heat energy loss in the house due to ventilation can be reduced. At the same time, the duct itself is required to have a heat insulating effect in order to prevent heat loss of cool air or hot air flowing in the ducts for blowing and collecting (hereinafter, referred to as ducts). Therefore, as shown in FIG. 5, for example, the heat insulating material 11 and the reinforcing body 12 are spirally wound to form a circular pipe, and the inner and outer walls of the pipe are sealed with the sealing material 13. Insulation material 11
As the reinforcing member 12, hard vinyl chloride is used, and as the sealing material 13, a soft vinyl chloride tape or the like is used.

[0005] Further, since the use of the duct leads to communication between the rooms in the house, the duct is also desired to have a sound deadening effect. Therefore, for example, as shown in FIG. 6, the heat insulating material 11 and the sound deadening material 14 are formed into a two-layer structure and the reinforcing body 12 is spirally wound to form a circular pipe, and the inner and outer walls of the pipe are sealed with the sealing material 13. Some things have been done. Foamed polyethylene is used as the heat insulating material 11, foamed polyurethane is used as the sound deadening material 14, hard vinyl chloride is used as the reinforcing member 12, and soft vinyl chloride tape is used as the sealing material.

However, depending on the structure of the house, there is a difference in the distance from the ventilating air conditioner to each room. Therefore, in a room far from the ventilating air conditioner, the duct length becomes longer, and heat loss is shorter than that of a short duct. growing. In other words, there is a problem that when cold air flows in the duct, the blowout temperature in the room is high in a long duct, and when hot air flows, the blowout temperature in the room is low in a long duct.

[0007] As a solution to this problem, an air flow of 6
There is a method of using a large air volume of about 00 m ³ / h to secure the heat transfer amount even in a long duct, but a large fan that generates a large air volume is required, and the ventilation and air conditioning equipment itself becomes large and heavy. As a result, there was a problem that the workability was reduced and the burden on the housing structure was increased.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems, and an object of the present invention is to provide a heat-insulating structure for a pipe duct used in a ventilation air conditioner. An object of the present invention is to provide an air layer having a small thermal conductivity in a portion to reduce heat loss from a duct and enhance energy saving performance.

[0009]

In order to solve the above-mentioned problems, a duct according to the present invention comprises a tubular body made of a heat insulating material having an air layer therein and a reinforcing body, and seals both sides of the tubular body. The first feature is that it is covered with a material.

Further, the duct of the present invention comprises a heat insulating material having an air layer therein, a sound deadening material, and a reinforcing member, and the front and back surfaces of the tubular body are covered with sealing materials. The feature is.

According to the first feature, heat loss from the duct pipe wall can be reduced in a duct connected to a ventilation air-conditioning system of a house or the like, so that a space in which a long duct is piped and air-conditioned is short. The difference in room temperature from the space in which the duct is piped and air-conditioned can be reduced, and the living space can be made comfortable.

Alternatively, when there is no difference in the duct length of the duct,
Due to the reduction of heat loss from the duct pipe wall, the amount of heat supplied to each room will be oversupplied if the blowing volume remains the same,
The amount of air that has been conditioned can be reduced. This makes it possible to reduce the size of the fan for indoor circulation ventilation built into the ventilation and air conditioning system, which makes it possible to reduce the size and weight of the ventilation and air conditioning system body, and at the same time to improve the workability, and at the same time, burden the residential structure. It is possible to improve the durability of the house by reducing it.

Further, according to the second feature, in a duct connected to a ventilation air conditioner of a house or the like, heat loss from a duct pipe wall can be reduced. Since the difference in room temperature from the space in which a short duct is piped and air-conditioned can be reduced, and the noise transmission effect between the rooms can be reduced by the noise reduction effect of the noise reduction material, the living space can be made comfortable.

Alternatively, when there is no difference in the duct length of the duct,
If the amount of air blown from the duct tube wall remains the same, the amount of heat supplied to each room becomes excessive, so that the amount of air blown by the conditioned air can be reduced. This makes it possible to reduce the size of the fan for indoor circulation ventilation built into the ventilation and air conditioning system, which makes it possible to reduce the size and weight of the ventilation and air conditioning system body, and at the same time to improve the workability, and at the same time, burden the residential structure. It is possible to improve the durability of the house by reducing it.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a duct according to a first embodiment of the present invention. The heat insulating material 21 is spirally wound in two layers, and a reinforcing body 22 is spirally wound in a spiral gap of the heat insulating material 21 to secure the strength of the duct. The inner and outer surfaces of the tube wall composed of the heat insulating material 21 and the reinforcing body 22 are covered with a sealing material 23 to isolate the inside and outside of the tube. The two layers of heat insulating material 21 are counterbore processed on the entire surface in contact with each other to form an air layer 24.

The heat insulating material 21 is preferably made of a material having a small thermal conductivity, for example, foamed polyethylene. As a material of the reinforcing member 22, a material having a strength that is curved but not bent is preferable, and for example, hard vinyl chloride is used. As the material of the sealing material 23, a material having excellent flexibility is preferable, and for example, a soft vinyl chloride tape is used.

Here, the heat insulating duct of the present invention is maintained at the entrance.
How much heat can be transferred to the exit
Calculate theoretically. The entire length of the duct was divided into n equal parts with a certain length L
When the air in the duct of the first length L from the inlet
The quantity of heat q ₁(Kcal) is
Desired. q₁= Πr^TwoL × C_v× (t₁-T₀) ... (1) Formula r: Duct inner diameter (m) L: Duct length (m) C_v : Constant volume specific heat of air (kcal / m^Three℃) t₁: Air in the first length L (m) duct divided equally
Temperature (° C) t₀: Air temperature around duct (° C) In addition, air in duct with length L (m) per unit time
Heat quantity q released to surrounding fluid_a(Kcal / h) isL: Duct length (m) α₁: Heat transfer coefficient between the inner surface of duct and air (kcal / m^Two
h ° C) r₁: Thickness of first heat insulation layer (m) r_i: Thickness of the i-th heat insulation layer (m) λ_i: Thermal conductivity (kcal / mh) of the i-th heat insulating layer
℃) α_Two: Heat transfer coefficient (kcal / m) between duct outer surface and air^Two
h ° C), and the time T during which air passes through this duct_s(H)
Is T_s= (Πr^TwoL) / Q ... Equation (3) Q: Air volume (m^Three/ H) Therefore, the time T_sAnd from the duct entrance divided into n equal parts
Heat loss q of the first length L duct_a1(Kca
l) is q_a1= Q_a× T_s... It is obtained by equation (4). Next, from the duct entrance, 2 divided into n equal parts
To the surrounding air per second duct L (m)
Heat q_Two(Kcal) is q_Two= Q₁-Q_a1= Πr^TwoL × C_v× (t_Two-T₀)… (5)
Equation t_Two: Inside the second length L (m) duct equally divided into n
It is expressed in air temperature (° C). From equation (5), t_TwoCan be sought,
In equation (2), t₁To t_TwoBy dividing by n
Surrounding fluid in a second length L (m) duct from the closed inlet
Quantity of heat released to_b(Kcal / h)
Wear. Further, from the equation (4), the time T_sWhere n is equally divided
Heat lost by the second length L duct from the entrance
_a2(Kcal) can be obtained. Again in equation (5)
And t_TwoTo t_ThreeThen, the third length L equally divided into n
(M) The air temperature (° C.) in the duct can be obtained.
By repeating the above calculations, the length L (m)
Air in the n-th length L (m) with the duct divided into n equal parts
In other words, the amount of heat retained at the duct outlet air can be determined.
You.

Next, using actual numerical examples, the heat insulation performance of the case where the present invention is not used and the case where the present invention is not used are compared, and the effect of the duct of the present invention is estimated. Now, in FIG. 5, the duct inner diameter is 100 mm, the duct length is 15 m, and the material of the heat insulating material 11 is foamed polyethylene (λ = 0.038 kc).
al / mh ° C.) It is assumed that only one layer has a thickness of 20 mm. Heat transfer coefficient between air inside and outside of duct is 10kc
al / m ² h ℃, ducts ambient temperature 10 ° C., warm air at 60 ° C. from the duct inlet is sent by air volume of 120 m ³ / h, the duct length is formed with a heat insulating material is, the length of the reinforcement portion Sufficiently larger than. If this duct is divided into, for example, 150 equal parts and the calculations of the above-described equations (1) to (5) are repeated for every 0.1 m in length, the retained heat of the air in the duct outlet of 0.1 m in length is 8.67. × 10 ^-3 kcal.

Now, regarding the duct of FIG.
100mm, duct length 15m, heat insulation material is foamed polyethylene for both layers (λ = 0.038kcal / mh ° C)
It is assumed that the thickness of one layer is 10 mm. However, each foamed polyethylene is subjected to a counterbore process, that is, a groove process, with a depth of 5 mm, and an air layer (λ
= 0.019 kcal / mh ° C). In other words, foamed polyethylene 5 mm from the inner surface of the duct, air layer 1
A total of 20 mm of 0 mm and again 5 mm of foamed polyethylene is the thickness of the duct tube wall. The heat transfer coefficient between the inner and outer surfaces of the duct and air is 10 kcal / m ² h ° C, the ambient temperature of the duct is 10 ° C, and hot air at 60 ° C from the duct entrance is 120 m ³ / h.
The duct length, which is sent at the air volume of
It is assumed that the length is sufficiently larger than the length of the duct portion where the air layer is not formed, that is, the portion of the foamed polyethylene that is not counterbored and the reinforcing portion. When this duct is divided into, for example, 150 equal parts and the calculation of the above-described equations (1) to (5) is repeated for every 0.1 m in length, the heat capacity of the air in the duct outlet of 0.1 m in length is 9.43. × 10 ^-3 kcal, compared with the case where only the foamed polyethylene is 20 mm thick as the heat insulating material.
The heat transfer amount is increased by about 9%. Alternatively, the air volume required to secure the same heat transfer amount as in the case where only the foamed polyethylene is 20 mm in the heat insulating material is 82 m ³ / h,
The air volume is reduced by 32% for 120 m ³ / h.

By arranging the air layer in the duct as described above, the heat insulating performance is enhanced, and thus the comfort of air conditioning in the space where the long duct is piped can be enhanced. Alternatively, when the heat supply is excessively supplied due to the improvement of the heat insulation performance, the amount of the blown air can be reduced. Can be downsized,
Improves workability and reduces load on housing structures.

FIG. 2 is a view showing a duct according to a second embodiment of the present invention. The heat insulating material 31 and the sound deadening material 32 are spirally wound in two layers, and in order to secure the strength of the duct, the reinforcing member 3 is provided in the spiral gap between the heat insulating material 31 and the sound deadening material 32.
3 is spirally wound. The inner and outer surfaces of the tube wall composed of the heat insulating material 31, the sound deadening material 32, and the reinforcing body 33 are covered with a sealing material 35 to isolate the inside and outside of the tube. The heat insulating material 31 and the sound deadening material 32 are counterbore-worked on the entire surface in contact with each other, and form an air layer 34.

The heat insulating material 31 is preferably made of a material having a small thermal conductivity, for example, foamed polyethylene. The material of the silencing material 32 is preferably one having an excellent silencing effect. For example, foamed polyurethane is used. As a material of the reinforcing member 33, a material having a strength which is curved but not bent is preferable, and for example, hard vinyl chloride is used.
As a material of the sealing material 35, a material having excellent flexibility is preferable, and for example, a soft vinyl chloride tape is used.

Similar to the first embodiment of the present invention, the heat insulation performance of a case where the present invention is not used and a case where the present invention is used are compared using actual numerical examples, and the effect of the duct of the present invention is estimated. I do. Now, in FIG.
mm, duct length 15 m, the material of the heat insulating material 11 is foamed polyethylene (λ = 0.038 kcal / mh ° C.), and the material of the sound deadening material 14 is foamed polyurethane (λ = 0.043 kca).
1 / mh ° C.), and each has a thickness of 10 mm. Heat transfer coefficient between air inside and outside of duct is 10kc
al / m ² h ℃, ducts ambient temperature 10 ° C., warm air at 60 ° C. from the duct inlet is sent by air volume of 120 m ³ / h, the duct length is formed with a heat insulating material is, the length of the reinforcement portion Sufficiently larger than. If this duct is divided into, for example, 150 equal parts and the calculations of the above-described equations (1) to (5) are repeated for every 0.1 m in length, the amount of heat retained in air within 0.1 m in the length of the duct outlet is 8. It becomes 62 × 10 ⁻³ kcal.

The duct of FIG. 2 has a duct inner diameter of 100 mm, a duct length of 15 m, a heat insulating material of foamed polyethylene (λ = 0.038 kcal / mh ° C.), and a sound deadening material of foamed polyurethane (λ = 0.043 kcal / m).
mh ° C.) and each thickness is 10 mm.
However, the foamed polyethylene which is a heat insulating material has been subjected to a counterbore processing with a depth of 5 mm, and an air layer (λ = 5 mm) having a thickness of 5 mm.
0.019 kcal / mh ° C). In other words, foamed polyethylene 5 mm, air layer 5
The total thickness of the duct tube wall is 20 mm, i.e., mm and 10 mm of the polyurethane foam. The heat transfer coefficient between the inner and outer surfaces of the duct and the air is 10 kcal / m ² h ° C, and the temperature around the duct is 10
The hot air of 60 ° C is sent from the duct inlet at a flow rate of 120m ³ / h, and the length of the duct forming the air layer is determined by the duct part without the air layer, that is, spot facing with foamed polyethylene It is assumed that it is sufficiently larger than the length of the part without the reinforcement and the part of the reinforcing body. This duct is divided into 150 equal parts,
When the calculations of the above equations (1) to (5) are repeated for every 0.1 m in length, the amount of heat retained in air with a duct outlet of 0.1 m in length is 9.09 × 10 ⁻³ kcal, and heat insulation is performed. The heat transfer amount is increased by about 6% as compared with the case where the thickness of the foamed polyethylene is only 20 mm. Alternatively, the air volume required to secure the same heat transfer amount as when the thickness of the heat insulating material is only 20 mm for foamed polyethylene is 97 m ³ / h.
The air volume is reduced by 19% for 20 m ³ / h.

As described above, by arranging the air layer in the duct, the heat insulating performance is enhanced. Therefore, it is possible to enhance the comfort of air conditioning in the space where the long duct is piped, while maintaining the noise reduction effect. Or, by improving the heat insulation performance,
In the case of excessive supply of heat, the amount of air blow can be reduced, so that the size of the fan or motor, that is, the size of the main body of the ventilation air-conditioning system, can be reduced while maintaining the silencing effect and heat transfer capacity equivalent to those of the conventional technology. It becomes possible to improve the workability and reduce the load on the housing structure.

In the above-described embodiment, the air layer is formed by subjecting the heat insulating material or the sound deadening material to the counterbore processing and overlapping them, but the hollow layer may be formed by one layer of the heat insulating material or the sound deadening material. . In the first and second embodiments, the reinforcing members are described as being spiral. However, the present invention is not limited to the spiral, and annular reinforcing members may be arranged at equal intervals.

[0027]

As described above, the duct for air-conditioning piping of the present invention, as described above, has an improved air-insulating performance by arranging an air layer in the duct, so that the comfort of air-conditioning in a space where a long duct is piped can be improved. In addition, the size of the ventilation fan or the motor, that is, the size of the main body of the ventilating air conditioner can be reduced while the heat transfer capacity is equal to that of the conventional technology, and the workability can be improved and the load on the house structure can be reduced.
Alternatively, it is possible to enhance the comfort of air conditioning in a space in which a long duct is piped, while maintaining the noise reduction effect.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a heat insulating duct with an air layer according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a heat insulating / muffling duct with an air layer according to an embodiment of the present invention.

FIG. 3 is a diagram showing the configuration of a 24-hour cooling / heating / ventilation system installed in a house.

FIG. 4 is a diagram showing a configuration of a ventilation / air-conditioning apparatus main body of the whole building 24-hour air conditioning / ventilation system.

FIG. 5 is a diagram showing an example of a configuration of a heat insulating duct according to the related art.

FIG. 6 is a diagram showing an example of a configuration of a heat insulating / muffling duct according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 House 3 Ventilation air-conditioner 4 Ventilation duct 7 Collection duct 8 Insulation material 9 Reinforcement body 10 Seal material 11 Sound-absorbing material 21 Insulation material 22 Reinforcement body 23 Seal material 24 Air layer 101 Exhaust outlet 102 External air inlet 103 Exhaust inlet 105 Circulating air inlet 106 Ventilation air supply fan 107 Ventilation exhaust fan 108 Indoor circulation ventilation fan 109 Total heat exchanger 110 Cooling / heating heat exchanger 112 Branch chamber

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenichi Yamaguchi 93 Edocho, Chuo-ku, Kobe, Hyogo Prefecture Inside the Noritz Co., Ltd. F term (reference) 3H111 AA02 BA15 CA03 CB05 CB24 CC07 DA13 DA15 DB11 DB18 3L080 AD00 AE01 AE02

Claims (2)

[Claims] 1. A duct for air-conditioning piping, wherein a tubular body is formed by a heat insulating material having an air layer therein and a reinforcing body, and both front and back surfaces of the tubular body are covered with sealing materials. 2. A duct for an air-conditioning pipe, wherein a tubular body is formed by a heat insulating material having an air layer therein, a sound deadening material, and a reinforcing body, and both front and back surfaces of the tubular body are covered with sealing materials.