KR20240082953A - Noise reduction duct - Google Patents

Abstract

The present invention includes a first duct that provides a space through which air inside the building flows, a second duct that is provided in communication with the first duct and provides a space through which air flowing in through the first duct flows out to the outside, and It relates to a noise reduction duct, which is provided inside the second duct and includes a noise reduction unit that provides a flow path to prevent the air inside the second duct from vortexing.

Description

Noise reduction duct {NOISE REDUCTION DUCT}

The present invention relates to noise reduction ducts.

For example, a flue duct system installed in large buildings such as apartments or factories to discharge combustion gases generated from these buildings is schematically shown in FIG. 1.

Referring to FIG. 1, combustion gas (exhaust gas) generated by the operation of the boiler 7 in the building is generally discharged to the outside of the building through a plurality of connected duct assemblies 1 and 2.

These duct assemblies (1, 2) are divided into a horizontal duct assembly (1) and a vertical duct assembly (2) depending on the installation state. Typically, the horizontal duct assembly 1 and the vertical duct assembly 2 are combined to form a flue duct system as shown in FIG. 1.

In order to support the horizontal duct assembly (1) and the vertical duct assembly (2), the fixed supports (4,8) are fixed and installed in parallel to the horizontal duct assembly (1) and the vertical duct assembly (2). do.

Meanwhile, in FIG. 1, reference numeral 3 denotes a stack cap, reference numeral 5 denotes a check hole for inspecting the inside of the duct assembly 2, and reference numeral 9 denotes the duct assembly. The expansion valve installed on one side of the duct assembly (2) is shown to vary the length of (2).

The configurations of the horizontal duct assembly 1 and the vertical duct assembly 2 are almost identical, as will be described later.

Therefore, in FIG. 2, the configuration of the duct assemblies 1 and 2 is explained by taking the configuration of the vertical duct assembly 2 among the duct assemblies 1 and 2 in FIG. 1 as an example.

Referring to FIG. 2, the duct assembly 2 is used to fasten the upper and lower (or front and rear) inner pipes 2b and 2b' and the flange 2b1 of the inner pipes 2b and 2b'. A first connection band (2e), outer tubes (2a, 2a') surrounding the outer peripheral surface of the inner tubes (2b, 2b') and installed at regular intervals on the outside of the inner tubes (2b, 2b'), It is configured to include a second connection band (2d) installed to fasten the external pipes (2a, 2a').

In addition, spacers (2c, 2c') are installed between the outer tubes (2a, 2a') and the inner tubes (2b, 2b') to support them and at the same time keep the distance between them constant. At this time, an air layer of about 25 mm is formed between the outer diameter (O.D.) and the inner diameter (I.D.) by the spacers (2c, 2c').

Accordingly, the duct assembly 2 of FIG. 2 forms a kind of double pipe consisting of outer pipes 2a and 2a' and inner pipes 2b and 2b'.

And Figure 3 shows another embodiment of the duct assembly.

In the duct assembly 6 of FIG. 3, intermediate pipes 6g and 6g' are installed between inner pipes 2b and 2b' and outer pipes 6a and 6a', and spacers 2c and 2c are provided between them, respectively. ',6b,6b') are provided. In addition, a first connecting band (2e) for fastening the inner tubes (2b, 2b') and a second connecting band (6d) for fastening the outer tubes (6b, 6b') are provided.

At this time, by the spacers (2c, 2c', 6b, 6b'), about 25mm ( An air layer of approximately 50 mm is formed.

Accordingly, the duct assembly 6 of FIG. 3 forms a kind of triple pipe consisting of outer pipes 6a and 6a', middle pipes 6g and 6g', and inner pipes 2b and 2b'.

In the duct assemblies 2 and 6 configured as above, a portion A is formed around the first connection band 2e, which is a type of V-band that fastens the flanges 2b-1 of the inner pipes 2b and 2b', respectively. A detailed illustration is shown in Figure 4.

Referring to FIG. 4, before fastening the flanges 2b-1 of the inner tubes 2b and 2b', heat-resistant sealant 2f is filled inside the first connection band 2e to increase fastening force. Alternatively, exhaust gas passing (flowing) inside the duct assemblies (2, 6) does not leak, and condensate formed on the inner walls of the duct assemblies (2, 6) does not leak.

And the first connection band 2e is finally fastened with the bolt nut assembly 2h, so that the inner tubes 2b and 2b' are tightly coupled.

In addition, the outer pipe is fastened by the second connection band, thereby completing the assembly of the duct assemblies 2 and 6 of the double pipe or triple pipe.

The duct assemblies 2 and 6 constructed as described above are generally made of stainless steel with excellent corrosion resistance and are connected to the exhaust gas discharge port of the underground heat source equipment (e.g., boiler), and these assemblies 2 and 6 are connected to each other. Assemble multiple units vertically or horizontally and connect them to the rooftop so that exhaust gas is discharged.

However, in the past, the temperature of the exhaust gas flowing inside the duct assembly was used at around 200°C to 250°C or lower, resulting in very little internal condensation. However, current heat source equipment (e.g., boilers) is equipped with a waste heat recovery device. As the exhaust gas temperature reaches 100℃~150℃, a large amount of condensate is generated.

In addition, if a waste heat recovery device is not applied to diesel generator or gas turbine generator equipment, the temperature of the exhaust gas will be discharged over 300℃~600℃, and at the same time, the pressure inside the duct assembly (2,6) will increase due to high-speed forced exhaust, and airtightness will be compromised. is being emphasized.

In response to this, as mentioned above, airtightness is simply maintained with a heat-resistant sealant (2f) in the first connection band (2e), which is a V-band, and no improvement plan suitable for the current conditions has been proposed, resulting in serious problems such as leakage and water leakage. It represents.

Specifically, even in the state where the first connection band 2e is fastened, there is a gap C between the flanges 2b-1 as shown in FIG. 4, so that several duct assemblies 2 and 6 are assembled. In this state, a gap opens inside the groove of the first connection band (2e) at the moment of air expansion inside the pipe at the moment of vibration, external impact, or ignition of equipment (e.g., boiler, etc.).

As this phenomenon progresses repeatedly, the adhesive strength of the heat-resistant sealant (2f) is reduced, and the heat-resistant sealant (2f) hardens and crumbles due to the high-temperature exhaust gas, thereby reducing airtightness. At this time, problems with exhaust gas smoke and condensate leakage occur.

Currently, even when the above problems (sequential smoke, water leakage) can be predicted, there is a lack of effort to improve the problems, so construction is proceeding in the existing way.

Accordingly, after completion of construction, defect repairs for noise, vibration, heat generation, smoke fumes, and water leakage are being carried out several times during test operation or use. In addition, due to equipment defects, the constructed duct assembly is dislodged during an explosion, resulting in re-construction and defects. There are significant economic losses due to repairs and many customer complaints.

On the other hand, although not shown in the drawing, in the past, in order to solve the sound absorption problem, a stainless steel plate was perforated regularly, made into a circular tube, and then the outer surface was first wrapped with glass cloth fiber, and then glass was placed on top of it. Sound-absorbing pipes secondaryly wrapped with wool or serac wool insulation were installed inside the duct assemblies (2,6) manufactured as above to increase sound absorption.

However, sound-absorbing pipes made of glass wool or serac wool insulation as described above have increased sound-absorbing performance for noise and vibration transmission, but water is absorbed by condensation or condensation, causing the insulating material to clump together in the direction of gravity, causing sound absorption. and the insulation performance is reduced.

In addition, as time passes, the fiber insulation material wears out and becomes torn, causing the problem that it is discharged into powder that is fatal to the human body and blown into the air.

The present invention was devised to solve the above-mentioned problems. When exhaust gas flows to the outside through a duct, a vortex is generated inside the duct, and the aim is to provide a noise reduction duct that reduces the resulting noise. Make it a task.

In addition, the present invention aims to solve the problem of providing a noise reduction duct that prevents water from flowing into the interior through the duct from the outside during rainy weather and damaging the internal air flow device.

In order to solve the above-described problem, the present invention provides a first duct that provides a space through which air inside the building flows, and is provided to communicate with the first duct, and the air flowing in through the first duct flows out to the outside. Providing a noise reduction duct comprising a second duct providing a space and a noise reduction unit provided inside the second duct and providing a flow path to prevent the air inside the second duct from swirling. It is used as a means of solving problems.

In addition, the noise reduction part includes a collection part that is provided in a cylindrical shape and collects external rainwater, a vortex formation prevention part that is in communication with the collection part and has a cross-sectional area that narrows downward, and a lower end of the vortex formation prevention part that communicates with the bottom of the vortex formation prevention part. A means of solving the problem is to provide a noise reduction duct, which is characterized in that it includes a drainage unit provided so as to drain rainwater collected in the collection unit toward the first duct.

In addition, a means of solving the problem is to provide a noise reduction duct, wherein the diameter of the end of the second duct is smaller than the diameter of the end of the collection part.

In addition, a means of solving the problem is to provide a noise reduction duct, characterized in that the ratio of the diameter of the end of the second duct to the diameter of the end of the collection part is 5:6.

In addition, a means of solving the problem is to provide a noise reduction duct, wherein the distance between the inner surface of the second duct and the outer peripheral surface of the noise reduction unit becomes wider in the direction of the first duct.

The present invention was developed to solve the above-mentioned problems, and can provide a noise reduction duct that reduces the noise generated by eddy currents generated inside the duct when exhaust gas flows out through the duct to the outside.

In addition, the present invention can provide a noise reduction duct that prevents water from flowing into the interior through the duct from the outside during rainy weather and damaging the internal air flow device.

Figure 1 schematically shows the configuration of a typical flue duct system.
FIG. 2 shows the configuration of one embodiment of the general flue duct assembly of FIG. 1.
FIG. 3 shows the configuration of another embodiment of FIG. 1.
Figure 4 shows an enlarged configuration of part A of Figures 2 and 3.
Figure 5 shows a cross-section of a noise reduction duct according to an embodiment of the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in more detail with reference to the accompanying drawings.

Prior to describing the present invention, the following specific structural and functional descriptions are merely illustrative for the purpose of explaining embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention may be implemented in various forms. It should not be construed as limited to the embodiments described herein.

In addition, since the embodiments according to the concept of the present invention can make various changes and have various forms, specific embodiments will be illustrated in the drawings and described in detail in this specification. However, this is not intended to limit the embodiments according to the concept of the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Figure 5 shows a cross-section of a noise reduction duct according to an embodiment of the present invention.

Referring to FIG. 5, the noise reduction duct according to an embodiment of the present invention is a first duct 100 that provides a space through which air inside the building flows, and is provided to communicate with the first duct 100, A second duct 200 provides a space through which air introduced through the first duct 100 flows out to the outside, and is provided inside the second duct 200, and the air inside the second duct 200 It may be provided to include a noise reduction unit 300 that provides a flow path to prevent eddy currents.

More specifically, the noise reduction unit 300 is provided in a cylindrical shape and includes a collection unit 310 that collects external rainwater, and a vortex that is provided in communication with the collection unit 310 and has a cross-sectional area that narrows downward. A drainage unit provided in communication with the formation prevention unit 330 and the lower end of the vortex formation prevention unit 330 to drain rainwater collected in the collection unit 310 toward the first duct 100. It may be provided to include (350).

In Figure 5, the drain unit 350 is provided toward the inner wall of the first duct 100, so that the rainwater collected in the collection unit 310 flows along the inner wall of the first duct 100. However, this is an example for convenience of explanation, and the user may optionally allow the drain unit 350 to penetrate the first duct 100 so that the collected rainwater is discharged to the outside of the first duct 100. It may be provided so that it can be done.

Meanwhile, the end diameter (OD1) of the second duct 200 may be smaller than the end diameter (OD2) of the collection unit 310.

More preferably, the ratio of the end diameter (OD1) of the second duct 200 and the end diameter (OD2) of the collection part 310 is preferably 5:6.

Since the end diameter (OD1) of the second duct 200 is smaller than the end diameter (OD2) of the collection unit 310, all rainwater flowing in from the outside through the second duct 200 is Since it can be collected inside the collection unit 310, rainwater flowing in from the outside flows into the center of the first duct 100 and an air discharge pump (not shown) discharges air into the first duct 100. It has the effect of preventing damage to the city.

Meanwhile, the distance between the inner surface of the second duct 200 and the outer peripheral surface of the noise reduction unit may be provided to widen toward the first duct 100.

As a result, the high-speed air flowing in from the first duct 100 can be prevented from creating a vortex inside the second duct 200, which has the effect of reducing noise inside the exhaust duct by more than 90%. .

More specifically, the air flowing into the first duct 100 moves to the area between the second duct 200 and the noise reduction unit 300. At this time, the second duct 200 and the noise reduction unit 300 move. As the cross-sectional area of the area between the noise reduction units 300 rapidly decreases, the speed of the fluid increases.

That is, according to Bernoulli's law, the air flowing in from the first duct 100 increases in speed as it passes between the second duct 200 and the noise reduction unit 300, creating a condition in which the fluid vortexes. Because of the offset, the exhaust duct of the present invention has a significant noise reduction effect.

Although the present invention has been shown and described with respect to specific embodiments, it is known in the art that the present invention can be variously improved and changed without departing from the gist or scope of the invention as provided by the following claims. It will be self-evident to those with ordinary knowledge.

Claims (5)

A first duct providing a space through which air inside the building flows;
a second duct provided in communication with the first duct and providing a space through which air introduced through the first duct flows out to the outside; and
A noise reduction duct provided inside the second duct and comprising a noise reduction unit that provides a flow path to prevent the air inside the second duct from vortexing. According to claim 1,
The noise reduction unit,
A collection unit provided in a cylindrical shape to collect external rainwater;
A vortex formation prevention unit provided in communication with the collection unit and provided with a cross-sectional area that narrows downward; and
A noise reduction duct comprising: a drain unit provided in communication with the lower end of the vortex formation prevention unit to drain rainwater collected in the collection unit toward the first duct. According to claim 2,
A noise reduction duct, characterized in that the diameter of the end of the second duct is smaller than the diameter of the end of the collection part. According to claim 3,
A noise reduction duct, characterized in that the ratio of the diameter of the end of the second duct and the diameter of the end of the collection part is 5:6. According to claim 3,
A noise reduction duct, characterized in that the distance between the inner surface of the second duct and the outer peripheral surface of the noise reduction unit widens in the direction of the first duct.