CN111380068B

CN111380068B - Smoke tube structure for improving heat efficiency

Info

Publication number: CN111380068B
Application number: CN201911035003.8A
Authority: CN
Inventors: 郑柱和; 金钟勋; 金治官
Original assignee: Daelim Royal EnP Co Ltd
Current assignee: Daelim Royal EnP Co Ltd
Priority date: 2018-12-31
Filing date: 2019-10-29
Publication date: 2022-06-07
Anticipated expiration: 2039-10-29
Also published as: CN111380068A; KR101995576B1

Abstract

The present invention relates to a smoke tube structure for improving heat efficiency, comprising: a tube that exchanges heat with an external heat medium by flowing combustion gas inside; and a turbulator installed inside the tube and formed in a spiral shape to guide a turbulent flow of the combustion gas; wherein the turbulator is further provided with a secondary promoting body formed in a streamline direction to diffuse a turbulent flow of the combustion gas for preventing a pressure loss of the combustion gas; the auxiliary promoting body of the turbulator comprises a vent hole and an expansion sheet, wherein the vent hole is formed along the streamline direction, and the expansion sheet is connected to the rear end of the vent hole to form an incline and gradually increase the surface area along the streamline direction. The smoke tube structure for improving thermal efficiency of the present invention is to facilitate heat exchange with a heat medium outside the tube by the flow of combustion gas, install a spiral turbulator inside the tube, and particularly introduce a sub-promotion body formed along a streamline direction into the turbulator, thereby not only diffusing the turbulent flow of combustion gas, but also preventing pressure loss.

Description

Smoke tube structure for improving heat efficiency

Technical Field

The present invention relates to a smoke tube structure for improving thermal efficiency, in which a spiral turbulator is installed inside a tube in order to promote heat exchange with a heat medium outside the tube by a flow of combustion gas, and in particular, a sub-promotion body formed in a streamline direction is introduced into the turbulator, thereby not only diffusing a turbulent flow of combustion gas, but also preventing a pressure loss.

Background

Generally, boilers may be classified into various types according to the material or structure of a body, a water circulation method, and the like. Among them, the steel boiler can be divided into a cylindrical boiler and a water tube boiler according to the structure, and the cylindrical boiler is a boiler in which a furnace tube or a smoke tube and the like are arranged inside a large-diameter cylindrical pressure vessel to increase the heat conduction area so as to increase the evaporation capacity.

A shaft boiler is a fire-resistant boiler in which a shaft (flow) having a relatively small diameter is installed inside a large-diameter casing, and a combustion device is provided in the shaft.

The flue tube boiler has a structure in which a plurality of flue tubes (fire tubes) having small diameters are provided and connected between flat plate-shaped end plates located at both ends of a casing, and has a large heat transfer area and a large evaporation capacity as compared with a boiler drum type boiler. The tube-flue boiler is manufactured by combining a tube boiler and a flue boiler, and has a structure in which a large-diameter corrugated tube and a plurality of flues are continuously arranged in a casing.

The boiler with corrugated tube has a structure with corrugated tube and multiple smoke tubes arranged side by side, and a burner is arranged in front of the boiler. High-temperature combustion gas combusted in the combustion chamber inside the furnace tube flows into the smoke tube, then passes through the vertically arranged smoke tube through a plurality of flues, and then is discharged to the chimney. A safety valve, a steam valve, etc. are installed at the upper part of the boiler.

The conventional smoke tube formed of a spiral round tube is configured to press the outside of the smoke tube to have a spiral protrusion inside the smoke tube, and is a scheme for forming a boundary layer of fluid in the smoke tube into a turbulent state in the process of flowing gas burned by the burner 12 inside the smoke tube to promote heat transfer. In addition to this, a solution of supplying the baffle gas to the inside of the smoke tube or inserting a spring-guided turbulent flow formed by winding an iron wire in a spiral inside the smoke tube is also disclosed.

However, in the case of the conventional smoke tube, if the spiral protrusion is formed in the tube by externally pressing the smoke tube itself, there is a problem of high manufacturing cost, and there are also problems such as: when machining round spiral pipes, scratches, one of the machining defects, frequently occur on the inside and outside, so that there is a risk of holes being formed due to the occurrence of localized corrosion, and the holes thus formed cause fluid leakage and thus a non-operational state.

Therefore, there is a need for a smoke tube structure that promotes turbulent flow of smoke tube gas inside the smoke tube, prevents the increase of manufacturing cost, and prevents the damage of the smoke tube.

(Prior art document)

(patent document)

(patent document 0001) Korean laid-open patent publication No. 2000-0013776 (2000.03.06-publication)

Disclosure of Invention

(problem to be solved)

The present invention has been made to solve the above-described problems.

One of the objects of the present invention is as follows: in order to promote heat exchange with the heat medium outside the pipe by the flow of the combustion gas, a spiral-shaped turbulator is installed inside the pipe, and particularly, a sub-promotion body formed in the streamline direction is introduced into the turbulator, thereby not only diffusing the turbulent flow of the combustion gas, but also preventing pressure loss.

Another object of the invention is as follows: the auxiliary boost body has vent holes formed in the streamline direction, and includes an expansion piece that is inclined in succession to the vent holes to gradually increase the surface area in the streamline direction, thereby not only maximizing turbulent flow while not obstructing the flow of combustion gas, but also minimizing pressure loss inside the pipe.

Other objects of the invention are as follows: a fixing piece is formed at the turbulator to contact with the inner surface of the pipe and support the turbulator, thereby stably supporting the turbulator inside the pipe, and at the same time, a micro protrusion is formed at the contact surface of the fixing piece contacting with the inner surface of the pipe, increasing the friction force between the inner surface of the pipe and the fixing piece, and doubling the fixing force.

Other objects of the invention are as follows: the pitch of the turbulator is formed narrowly at the outlet side of the combustion gas, increasing the thermal contact area between the combustion gas and the external heat medium, extending the residence time of the combustion gas, and uniformly maintaining the heat exchange distribution.

(means for solving the problems)

The smoke tube structure for improving heat efficiency of the present invention comprises: a tube that exchanges heat with an external heat medium by flowing combustion gas inside; and a turbulator installed inside the tube and forming a spiral shape to guide a turbulent flow of the combustion gas; wherein the turbulator further has a secondary promoting body formed along a streamline direction to diffuse a turbulent flow of the combustion gas for preventing a pressure loss of the combustion gas.

The secondary facilitator includes: a vent hole formed along a streamline direction; and the expansion piece is connected to the rear end of the vent hole to form an incline, and the surface area of the expansion piece is gradually increased along the streamline direction.

The vent hole and the expansion piece of the auxiliary promotion body are formed by a plurality of lines along the streamline direction; and the expansion pieces of each line are alternately arranged in a protruding manner in the front direction and the rear direction by taking the spiral surface of the turbulator as the center.

The turbulator of the present invention also has a fixing plate formed at an edge position and contacting an inner face of the tube to support the turbulator.

The fixing sheet of the present invention further has a minute protrusion on a contact surface contacting the inner surface of the tube to increase a frictional force.

The present invention forms the helical pitch of the turbulator narrower at the outlet side of the combustion gas.

(Effect of the invention)

The smoke tube structure for improving thermal efficiency of the present invention is to facilitate heat exchange with a heat medium outside the tube by the flow of combustion gas, to install a spiral turbulator inside the tube, and particularly to introduce a sub-promotion body formed along a streamline direction into the turbulator, thereby not only diffusing the turbulent flow of combustion gas, but also preventing pressure loss.

The present invention has, as a sub-promoting body, a vent hole formed in a streamline direction, and includes an expansion piece that is inclined in succession to the vent hole to gradually increase a surface area in the streamline direction, thereby not only maximizing turbulent flow while not obstructing combustion gas flow, but also minimizing pressure loss inside the tube.

The invention forms a fixing piece on the turbulator to contact the inner surface of the tube and support the turbulator, so as to stably support the turbulator in the tube, and forms a tiny bulge on the contact surface of the fixing piece contacting with the inner surface of the tube, thereby increasing the friction force between the inner surface of the tube and the fixing piece, and doubling the fixing force.

The invention forms the screw pitch of the turbulator at the outlet side of the combustion gas narrowly, increases the heat contact area between the combustion gas and the external heat medium, prolongs the retention time of the combustion gas, and uniformly maintains the heat exchange distribution.

Drawings

FIG. 1 is a partially cut-away perspective view showing a smoke tube structure for improving thermal efficiency of the present invention;

FIG. 2 is a perspective view and an enlarged view showing a turbulator of a smoke tube structure for enhancing heat efficiency of the present invention;

FIG. 3 is a sectional side view and an enlarged view showing another embodiment of the smoke tube structure for improving thermal efficiency according to the present invention;

fig. 4 is a sectional side view showing another embodiment of the smoke tube structure for improving thermal efficiency of the present invention.

(description of reference numerals)

FL: streamline direction OS: an outlet side

F: front direction B: rear direction

10: pipe

20: turbulent device

21: spiral surface 23: auxiliary promoter

23 a: vent hole 23 b: expansion sheet

25: the fixing piece 25 a: micro-convex part

Detailed Description

For the purpose of illustrating the invention, its operational advantages and objects attained by practice of the invention, preferred embodiments of the invention are illustrated below, and the invention is described with reference to the preferred embodiments.

First, the terms used in the present application are used for the purpose of describing particular embodiments only, and there is no intention to limit the present invention, and a singular expression may include a plural expression unless it is explicitly defined in the text. In the present application, the terms "including" or "having" and the like should be understood to specify the presence of the features, numerals, steps, actions, components, parts, or combinations thereof described in the specification, and do not exclude the presence or addition of one or more other features, numerals, steps, actions, components, parts, or combinations thereof in advance.

In describing the present invention, it is determined that specific descriptions of related well-known structures or functions may obscure the gist of the present invention, and the detailed descriptions thereof will be omitted.

As shown in fig. 1 and 2, the smoke tube structure for improving thermal efficiency of the present invention includes a tube 10 for exchanging heat with an external heat medium by flowing combustion gas inside, and a turbulator 20 installed inside the tube 10 to form a spiral shape for guiding turbulent flow of the combustion gas.

First, as shown in fig. 1 and 2, the combustion gas from the burner of the boiler flows into the tube 10 of the present invention and exchanges heat with the heat medium outside the tube 10, wherein the heat medium is water.

Therefore, the tubes 10 are arranged in a plurality of rows in the boiler drum, and function to transfer heat of the combustion gas to water to exchange heat with the water inside the boiler drum. Further, as shown, the tube 10 may be formed of a simple cylindrical tube body, but a spiral-shaped tube 10 may also be used in order to improve heat exchange efficiency.

Then, as shown in fig. 1 and 2, the turbulator 20 of the present invention is formed by twisting a plate-shaped member into a spiral shape, thereby promoting a turbulent flow of the combustion gas flowing inside the tube 10 and improving heat exchange efficiency with the heat medium outside the tube 10.

That is, the turbulator 20 of the present invention turbulates the flow of the combustion gas to improve the heat transfer efficiency, and at this time, in order to further promote the turbulent flow of the combustion gas generated by the turbulator 20 and to prevent the pressure loss inside the pipe 10, the sub-promoter 23 is introduced in the present invention. Hereinafter, the turbulator 20 having the secondary promoting body 23 will be described in more detail.

As shown in fig. 1 and 2, the sub-promoting body 23 of the turbulator 20 of the present invention is composed of a vent hole 23a and an expansion piece 23b, the vent hole 23a is formed along the flow direction of the combustion gas, i.e., the streamline direction FL, and the expansion piece 23b is connected to the vent hole 23 a.

The sub-promoting body 23 of the turbulator 20 of the present invention is formed along the streamline direction FL, and first the vent holes 23a of the sub-promoting body 23 are formed along the streamline direction FL, and the combustion gas is guided to flow from the front side space to the rear side space or from the rear side space to the front side space with reference to the spiral surface 21 of the turbulator 20. That is, the vent holes 23a of the sub-promoting body 23 function to prevent excessive pressure loss due to friction increase by the flow of the turbulent combustion gas.

Then, the expansion pieces 23b of the sub promoting body 23 gradually increase the surface area along the streamline direction FL. For this, as shown in fig. 2, the expansion piece 23B is formed in a triangular shape in which one vertex of the triangle is connected to the helicoid 21 of the turbulator 20 by the vent hole 23a to be formed to protrude in the front direction F, the rear direction B, or all the front and rear directions of the helicoid 21.

The sub promoting body 23 is formed into a plurality of lines along the streamline direction FL, and as shown in fig. 2 (a), the extension pieces 23b arranged at the upper and lower portions of the extension pieces 23b of the sub promoting body 23 are each constituted by extension pieces positioned at three positions. Meanwhile, as shown in fig. 2 (a) and (B), when the first and third expansion pieces 23B protrude in the rear direction B of the spiral surface 21 from the left among the expansion pieces 23B arranged in the upper line, the second expansion piece 23B protrudes in the front direction F of the spiral surface 21.

As shown in fig. 2 (a) and (B), when the first and third expanding pieces 23B of the expanding pieces 23B arranged on the lower line project in the front direction F of the spiral surface 21 from the left side, the second expanding piece 23B projects in the rear direction B of the spiral surface 21. That is, the expansion pieces 23B arranged on the upper and lower lines alternately protrude in the front and rear directions B.

In the case of the above-described configuration, the combustion gas promoted by the extension piece 23b of the sub-promoter 23 is promoted to be turbulent in a form diffused through the extension piece 23b, and the combustion gas flowing into the vent hole 23a based on one extension piece 23b and the combustion gas passing through the extension piece 23b are mixed with each other to obtain a more turbulent effect, whereby the heat exchange efficiency can be doubled.

The reason why the expansion piece 23B of the sub promoting body 23 is alternately projected in the front face direction F and the rear face direction B with reference to the spiral face 21 is as follows: since the combustion gas flowing into the pipe 10 flows along the front and rear surfaces of the helicoid 21 with reference to the helicoid 21, the expansion pieces 23b protrude in both directions from the front and rear surfaces of the helicoid 21, and the combustion gas is guided to be uniformly and turbulently fluidized in the entire flow passage.

In fig. 2, the vent holes 23a and the expansion pieces 23b disposed in the upper and lower lines of the sub-promoting bodies 23 are disposed at three positions, respectively, but the positions of installation may be increased or decreased by considering the sizes of the pipe 10 and the turbulators 20, the types of fluids, the internal pressure, and the like, and reflecting the design.

As shown in fig. 3, the present invention may have fixing plates 25 at the turbulator 20, the fixing plates 25 stably fixing the turbulator 20 in the state where the turbulator 20 is installed inside the pipe 10.

Fixing plates 25 of the turbulator 20 are formed at the upper and lower ends of the spiral and contact the inner surface of the tube 10 to support the turbulator 20. In this case, the fixing pieces 25 disposed at the upper and lower ends of the spiral are alternately disposed, respectively, and the upper and lower ends of the spiral contact the inner surface of the pipe 10 alternately with the fixing pieces 25. Accordingly, a predetermined space through which the combustion gas can flow may be formed in a portion where the fixing piece 25 contacts the inner surface of the pipe 10 because the height spiral of the fixing piece 25 is spaced apart from the inner surface of the pipe 10. However, since the next flow path is closed by being spirally brought into contact with the inner surface of the pipe 10, the combustion gas can be caused to flow in the streamline direction.

Further, it is preferable that the minute protrusions 25a are formed on the contact surface of the fixing pieces 25 of the turbulator 20 contacting the inner surface of the pipe 10 to increase the frictional force between the fixing pieces 25 and the inner surface of the pipe 10, and further to increase the supporting force of the fixing pieces 25 supporting the turbulator 20, so that the turbulator 20 can be stably mounted inside the pipe 10.

On the other hand, as shown in fig. 4, in order to further improve the heat efficiency, the turbulator 20 of the present invention forms a narrow flow path of the combustion gas on the outlet side OS, and enlarges the thermal contact area on the outlet side OS, thereby further improving the heat exchange efficiency.

Therefore, as shown in fig. 4, if the helical pitch of the combustion gas outlet side OS turbulator 20 is formed to be narrow, the flow path of the combustion gas is narrowed to the same extent. Accordingly, the stay of the combustion gas is extended on the outlet side OS, and the thermal contact area between the external heat medium and the combustion gas is increased.

Accordingly, the temperature at the time of inflow of the combustion gas is relatively higher than that at the time of outflow, but the temperature of the combustion gas flowing along the turbulator 20 gradually decreases while moving toward the outlet side OS by heat transfer with the external heat medium.

Therefore, if the spiral pitch is formed to be narrow in the outlet side OS where the temperature is reduced to form a narrow flow path, the thermal contact area between the external heat medium and the combustion gas in the outlet side OS is increased to the same extent while the residence time of the combustion gas is extended, and thus uniform heat exchange distribution can be secured by the entire length of the turbulator 20.

The turbulator 20 of the present invention configured as described above is installed inside the pipe 10 to promote heat exchange with the heat medium outside the pipe 10 by the flow of the combustion gas, and particularly, the sub-promoting body 23, i.e., the extension piece 23b, formed in the turbulator 20 in the streamline direction can not only diffuse the turbulent flow of the combustion gas, but also prevent pressure loss by the vent hole 23a of the sub-promoting body.

In addition, the turbulator 20 of the present invention can be stably fixed inside the tube 10 by the fixing pieces 25, and the helical pitch of the turbulator 20 is narrowly formed at the outlet side OS of the combustion gas, thereby having a uniform heat exchange distribution through the entire length of the turbulator 20, and thus being capable of maximizing heat exchange efficiency.

As described above, the present invention has been described with reference to one embodiment shown in the drawings, but this is merely exemplary, and those having ordinary skill in the art will understand that various modifications and equivalent other embodiments can be implemented by the embodiment.

Therefore, the true technical scope of the present invention should be determined by the technical idea of the claims.

Claims

1. A smoke tube structure for improving heat efficiency, comprising:

a pipe (10) for exchanging heat with an external heat medium by flowing combustion gas inside; and

a turbulator (20) mounted inside the tube (10) and forming a spiral shape to guide a turbulent flow of combustion gas;

wherein a secondary promoting body (23) is further provided at the turbulator (20), the secondary promoting body (23) being formed along a streamline direction (FL) to diffuse a turbulent flow of the combustion gas for preventing a pressure loss of the combustion gas;

the secondary promoter (23) comprises:

a vent hole (23a) formed along the streamline direction (FL);

an expansion piece (23b) which is connected to the rear end of the air vent (23a) and is inclined, and the surface area of which is gradually increased along the streamline direction (FL),

the air vent (23a) and the expansion piece (23b) of the auxiliary promotion body (23) are composed of a plurality of lines along the streamline direction (FL),

the expansion tabs (23B) arranged at the upper line and the expansion tabs (23B) arranged at the lower line of the plurality of lines are alternately arranged convexly in a front direction (F) and a rear direction (B) along the respective lines with the spiral face (21) of the turbulator as a center,

the expansion tabs (23B) arranged at the upper line and the expansion tabs (23B) arranged at the lower line of the plurality of lines are arranged corresponding to each other on the helicoid (21) of the turbulator and the expansion tabs (23B) corresponding to each other are arranged alternately protruding from each other in a front direction (F) and in a rear direction (B),

further having a fixing plate (25) at the turbulator (20), the fixing plate (25) being formed at an edge position and contacting an inner face of the tube (10) to support the turbulator (20),

the fixing pieces (25) are alternately arranged at upper and lower ends of a spiral of the turbulator (20), and the upper and lower ends of the spiral contact the inner surface of the pipe (10) alternately with the fixing pieces (25).

2. The smoke tube structure for improving thermal efficiency according to claim 1,

the fixing piece (25) further has a minute protrusion (25a) on a contact surface contacting with the inner surface of the tube (10) to increase a frictional force.

3. The smoke tube structure for improving thermal efficiency according to claim 1,

the helical pitch of the turbulator (20) is formed narrowly on the Outlet Side (OS) of the combustion gas.