KR102413066B1 - Shell and tube type heat exchanger including dual tube - Google Patents

Abstract

The present invention relates to a cylindrical shell-and-tube heat exchanger, and more particularly, in order to solve the phenomenon that the outer tube is frozen when cryogenic fluid flows into the tube, a heated fluid is provided with an inner tube inside the tube and the tube It relates to a cylindrical shell-and-tube heat exchanger of the dual tube type that allows flow between the inlet tubes.
To this end, the present invention provides a shell through which a high temperature first fluid flows, a plurality of tubes provided inside the shell and a cryogenic second fluid flowing through, and a plurality of baffles alternately installed inside the shell. As a cylindrical shell-and-tube heat exchanger including a baffle, it has a tube shape with a smaller diameter than a tube, and further includes an inner tube that is provided inside the inlet of the tube and into which the second fluid flows, the inner tube is , It is composed of a locking jaw formed at the front end so as to be caught on the inlet of the tube, a front end connected to the locking jaw, a center connected to the front end, and a rear end connected to the center, and the high-temperature agent flowing into the front end of the inner tube 2 The fluid flows out from the rear end, and the leaked second fluid is heated by the high-temperature first fluid flowing into the shell and flows into the space between the inner tube and the tube, characterized in that heat exchange is additionally performed.

Description

Dual tube type cylindrical shell heat exchanger {SHELL AND TUBE TYPE HEAT EXCHANGER INCLUDING DUAL TUBE}

The present invention relates to a cylindrical shell-and-tube heat exchanger, and more particularly, when a cryogenic fluid flows into a tube, in order to solve the phenomenon that the outer edge of the front end of the tube is frozen, a heated fluid is provided with an inner tube inside the tube It relates to a dual-tube type cylindrical shell-and-tube heat exchanger that flows between a tube and an inlet tube to further perform heat exchange.

In general, a shell and tube type heat exchanger is widely used for heat exchange of liquids.

In a cylindrical shell-and-tube heat exchanger, which is a typical type of heat exchanger, a plurality of metal tubes made of a copper alloy or the like are disposed in a shell in parallel to the shell. A high-temperature fluid flows inside the shell, that is, the outside of the tube, and a cryogenic fluid flows inside the tube, and heat exchange of the cryogenic fluid flowing through the tube is made.

As a cylindrical shell-and-tube heat exchanger, Korean Patent Publication No. 10-1512224 and Korean Patent Application Laid-Open No. 10-2007-0084401 have been disclosed. Such a conventional cylindrical shell-and-tube heat exchanger is shown in FIG. 1 . 1 is a cylindrical shell-and-tube heat exchanger according to the prior art.

1, the cylindrical shell-and-tube heat exchanger 200 includes a shell 210 through which the first fluid 70 flows, a plurality of tubes provided inside the shell 210 and through which the second fluid 80 flows ( tube; 220), and a plurality of baffles 230 alternately installed in the interior of the shell 210. The heat exchange of the second fluid 80 flowing into the tube 220 is performed by the first fluid 70 flowing inside the shell 210 .

However, in this conventional cylindrical shell-and-tube heat exchanger 200, the second fluid 80 flowing into the tube 220 is in a cryogenic state, and therefore, the wall surface temperature of the tube 220 is very low. In this state, when the flow rate and temperature of the first fluid 70 flowing inside the shell 210 are not sufficient, a freezing (freezing; A) phenomenon occurs on the outer wall surface of the tube 220 . A state in which the freezing phenomenon has occurred on the outer wall surface of the tube 220 is shown in FIG. 2 . 2 is a view showing a state in which the freezing phenomenon occurs in the cylindrical shell-and-tube heat exchanger according to the prior art.

As shown in Figure 2, when the freezing phenomenon (A) occurs on the outer wall surface of the tube 220, the first fluid 70 does not flow between the plurality of tubes 220, there is a problem in that the performance of the heat exchanger is eventually deteriorated. .

Republic of Korea Patent Publication No. 10-1512224 Republic of Korea Patent Publication No. 10-2007-0084401

The present invention has been devised to solve the above problems, and an object of the present invention is to provide a dual tube type cylindrical shell-and-tube heat exchanger that does not cause icing on the outer wall surface of the tube.

And an object of the present invention is to provide a dual tube type cylindrical shell-and-tube heat exchanger in which the problem of poor performance of the heat exchanger can be solved.

Together with this, other objects and advantages of the present invention will be described below, which are further provided by means and combinations within the scope that can be easily derived therefrom, as well as the disclosure of the matters described in the claims of the present invention and examples thereof. It is added that it will be covered in a wide range.

The present invention for achieving the above object is a shell through which a high-temperature first fluid flows, a plurality of tubes provided inside the shell and through which a cryogenic second fluid flows, alternately inside the shell A cylindrical shell-and-tube heat exchanger including a plurality of baffles installed as Further comprising a tube, wherein the inner tube (inner tube), a locking jaw formed at the front end to be caught on the inlet of the tube, a front end connected to the locking jaw, a center connected to the front end, and the center It consists of a rear end connected to, the high-temperature second fluid flowing into the front end of the inner tube flows out from the rear end, and the leaked second fluid flows into the shell in the high-temperature first fluid. It is heated by the flow into the space between the inner tube and the tube, characterized in that the heat exchange is additionally made.

And according to a preferred embodiment of the present invention, the inlet tube is characterized in that it is provided with a length from the inlet of the tube to any one point between the 1/3 point and the 2/3 point.

In addition, according to a preferred embodiment of the present invention, the inlet tube is characterized in that the length can be adjusted in the center.

And according to a preferred embodiment of the present invention, the inner tube, characterized in that the engaging jaw is coupled by expansion or welding at the inlet of the tube.

As described above, according to the present invention, the following effects can be expected.

By providing a dual tube type cylindrical shell-and-tube heat exchanger by providing an inner tube inside the tube into which the cryogenic second fluid flows, additional heat exchange is made between the tube and the inner tube, thereby preventing the freezing phenomenon occurring on the outer wall of the tube. There is an effect that can be done.

That is, the second fluid flowing out from the inner tube flows between the tube and the inner tube. At this time, since it is heated by the first fluid flowing out of the tube, heat exchange is performed by the first fluid that was originally flowing and heating is performed at the same time. Additional heat exchange is achieved by the flow of the second fluid. Accordingly, it is possible to prevent the freezing phenomenon occurring on the outer wall surface of the tube.

And, due to this, there is an effect that the problem that the performance of the heat exchanger is deteriorated can be solved.

Along with this, other effects of the present invention are not only the matters described in the above-described embodiments and claims of the present invention, but also effects that can occur within the range that can be easily followed from them, and the possibility of potential advantages contributing to industrial development It is added that they will be covered in a wider range by the

1 is a view showing a cylindrical shell-and-tube heat exchanger according to the prior art.
2 is a view showing a state in which the freezing phenomenon occurs in the cylindrical shell-and-tube heat exchanger according to the prior art.
3 is a view showing a dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.
4 is a view showing the inner tube of the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.
5 is a view showing the flow of the inner tube and fluid in the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.
6 is an enlarged view showing a state in which additional heat exchange is performed at the rear end of the inner tube in the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.
7 is a photograph showing the front side of a state in which the inner tube is installed in the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.
8 is a graph showing the temperature change of the outer tube in the cylindrical shell-and-tube heat exchanger according to the prior art and the dual-tube type cylindrical shell-and-tube heat exchanger according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention and methods of achieving them before the description will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. And the terms used in this specification are for describing embodiments and are not intended to limit the present invention, and among these terms, the singular form also includes the plural unless specifically stated in the phrase, and is a word indicating a direction in the description Note that this is to help the understanding of the description and can be changed depending on the time point.

Hereinafter, a dual tube type cylindrical shell-and-tube heat exchanger according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. 3 is a view showing a dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.

Referring to FIG. 3 , the dual tube type cylindrical shell-and-tube heat exchanger 100 according to the present invention includes a shell 10 , a tube 20 , a baffle (not shown), and an inner tube 50 .

In the shell 10, the first fluid 70 flows. The first fluid 70 has a high temperature and flows for heat exchange of the second fluid 80 flowing into the tube 20 . As indicated by arrows, the shell 10 is provided with an inlet (not shown) and an outlet, so that the first fluid 70 can be introduced and discharged. In this embodiment, although the outlet of the shell 10 is shown as an example that is provided in the upper portion of the front side, it is not limited to this form. And, although the shell 10 has been illustrated as an example of a cylindrical shape having a circular longitudinal cross-section, it is not limited to this shape and may have other shapes.

A plurality of baffles (not shown) are alternately installed inside the shell 10 . The baffle changes the flow of the first fluid 70 flowing into the shell 10 . That is, the baffles are disposed to be spaced apart from each other at a predetermined distance with respect to the transverse direction of the shell 10 in order to guide the flow of the first fluid 70 to meander with respect to the longitudinal direction of the shell 10 . The number and spacing of the baffles may be variously changed according to the capacity and shape of the shell 10 .

Since the baffles are alternately arranged in a zigzag form on the upper and lower portions inside the shell 10, the flow of the first fluid 70 introduced into the inlet of the shell 10 is shown in Figs. As shown in), it flows while forming a curve, and flows out to the outlet of the shell 10 . In this way, the first fluid 70 flowing in a curve by the baffle can make a lot of contact with the tube 20, so that heat exchange performance is improved.

A plurality of tubes 20 are provided inside the shell 10 . The tube 20 has a hollow cylindrical shape, and is inserted through the shell 10 in the longitudinal direction. A second fluid 80 of cryogenic temperature flows into the tube 20 . The second fluid 80 flowing into the tube 20 exchanges heat with the first fluid 70 flowing into the shell 10 . In the drawings, the tube 20 is shown as an example provided with four, but this is not limited to this form as a simplified illustration for the sake of explanation.

The inner tube (50) is a tube shape having a smaller diameter than the tube (20). The inlet tube 50 is provided inside the inlet of the tube 20 , and the second fluid 80 is introduced thereinto. Inlet tube 50 is provided inside the tube 20 to form a dual tube (dual tube). The inlet tube 50 may be provided with a length from the inlet of the tube 20 to any point between the 1/3 point and the 2/3 point. Since the conventional problem was the freezing phenomenon occurring at the inlet of the tube 20 , the inner tube 50 provided to solve this problem to generate additional heat exchange is 1/3 point from the inlet of the tube 20 . It is preferable to be provided with a length to any point between the 2/3 point.

The internal tube 50 will be described in more detail with reference to FIGS. 4 and 5 .

4 is a view showing the inner tube of the dual tube type cylindrical shell and tube heat exchanger according to the present invention, Figure 5 is a view showing the flow of the internal tube and fluid in the dual tube type cylindrical shell and tube heat exchanger according to the present invention to be.

Referring to FIGS. 4 and 5 , the inner tube 50 includes a locking jaw 51 , a front end 53 , a central portion 55 , and a rear end 57 . The locking jaw 51 is formed at the front end of the inner tube 50 so as to be caught on the inlet of the tube 20 . The locking jaw 51 is provided so as to be caught on the front end of the tube 20, as shown in FIG. The first and second fluids 70 and 80 do not flow between the front end of the inlet tube 50 and the front end of the tube 20 . For example, as shown in FIG. 7 , the interlocking jaw 51 of the internal tube 50 and the front end of the tube 20 are coupled by a method such as pipe expansion or welding, so that there is a gap between the internal tube 50 and the tube 20 . make sure not to 7 is a photograph showing the front of a state in which the inner tube is installed in the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.

The inner tube 50 is provided with a front end 53 connected to the locking protrusion 51 , a center 55 is provided at the rear end of the front end 53 , and a rear end 57 is provided at the rear end of the center 55 . ) is provided. The front end 53 , the center 55 , and the rear end 57 are provided with a predetermined distance from the tube 20 so that the second fluid 80 can flow between the tube 20 and the tube 20 . That is, the diameters of the front end 53 , the center 55 , and the rear end 57 are smaller than the diameter of the tube 20 , and a gap through which the second fluid 80 can flow is formed.

Here, the diameter of the front end 53 and the rear end 57 is the same, it is characterized in that the diameter of the front end 53 and the rear end 57 is larger than the diameter of the center (55). Due to the configuration of the internal intake tube 50 , it is easy for the second fluid 80 to flow between the internal intake tube 50 and the tube 20 , and heat exchange may also be performed in addition. That is, in addition to the heat exchange by the first fluid 70 flowing out of the tube 20, additional heat exchange is made by the second fluid 80 flowing out from the inner tube 50 and flowing between the tube 20 and , the problem that the freezing phenomenon occurs at the front end of the tube 20 can be solved.

In addition, due to the difference in diameter, that is, due to the central portion 55 having a smaller diameter than the front end portion 53, the flow rate of the second fluid 80 in the central portion 55 is increased, so that the cryogenic second fluid ( Since 80) flows quickly, there is an effect of minimizing the occurrence of freezing due to the temperature difference between the inside and the outside of the tube 20 .

And due to the difference in diameter, the inner tube 50 through which the cryogenic second fluid 80 flows, for example, the center 55 and the outside of the tube 20 are separated from each other, and freezing occurs due to the temperature difference. There is also an effect that can minimize the phenomenon.

The additional heat exchange by the inlet tube 50 will be described in more detail with reference to FIG. 6 . 6 is an enlarged view showing a state in which additional heat exchange is performed at the rear end of the inner tube in the dual tube type cylindrical shell-and-tube heat exchanger according to the present invention.

5 and 6 , when the second fluid 80 is introduced, the second fluid 80 is introduced into the front end 53 of the inner tube 50 inside the tube 20 . At this time, the first fluid 70 is flowing inside the shell 10 .

The second fluid 80 passing through the inlet tube 50 flows out to the rear end 57 of the inlet tube 50 , and as shown in FIG. 6 , between the tube 20 and the inlet tube 50 . It flows back into space and flows. The second fluid 80 discharged from the intake tube 50 flows to the central portion 55 and the front end portion 53 of the intake tube 50 .

For this reason, since the second fluid 80 heated by the first fluid 70 flows to the outside of the inlet tube 50, additional heat exchange is performed. That is, as in the prior art, in a state where the first fluid 70 flows to the outside of the tube 20 and heat exchange with the second fluid 80 is performed, the second fluid with heat exchanged flowing out from the inner tube 50 is performed. As 80 is introduced between the tube 20 and the inlet tube 50 , heat exchange is additionally performed with the second fluid 80 . Accordingly, due to the cryogenic second fluid 80 , the freezing phenomenon occurring at the front end of the tube 20 does not occur.

8 is a graph showing the results of an experiment showing the temperature change of the outer tube in the dual tube type cylindrical shell and tube heat exchanger 100 according to the present embodiment and the conventional cylindrical shell and tube heat exchanger. 8 is a graph showing the temperature change outside the tube in the cylindrical shell-and-tube heat exchanger according to the prior art and the dual-tube type cylindrical shell-and-tube heat exchanger according to the present invention.

As shown in FIG. 8, looking at the temperature of the outer tube as time goes by, in the conventional heat exchanger, the temperature is extremely low in a short time and eventually freezing occurs, whereas the dual tube type cylinder according to the present embodiment In the tubular heat exchanger 100, it was confirmed that the heat exchange is carried out gradually.

On the other hand, the dual tube type cylindrical shell-and-tube heat exchanger 100 according to the present embodiment may have a shape in which the length can be adjusted in the central portion 55 of the inner tube 50 . For example, like a fishing rod, by configuring the central portion 55 of the inner tube 50 to adjust the length in a folded form, the length of the inner tube 50 inside the tube 20 may be easily adjusted.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains may make various modifications, changes and substitutions within the scope without departing from the essential characteristics of the present invention. will be. And as described above, the embodiments disclosed in the present invention and the accompanying drawings are intended to explain, not to limit the technical spirit of the present invention, and the scope of the technical spirit of the present invention is limited by these embodiments and the accompanying drawings it is not going to be The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100: dual tube type cylindrical shell-and-tube heat exchanger
10: shell
20: tube
50; inner tube
51; stumbling block
53; front end
55; center
57; rear end
70, 80; fluid

Claims (4)

A shell through which a high temperature first fluid flows, a plurality of tubes provided inside the shell and through which a cryogenic second fluid flows, a plurality of baffles alternately installed inside the shell In a cylindrical shell-and-tube heat exchanger comprising a,
It has a tubular shape with a smaller diameter than the tube, and is provided at a predetermined interval inside the inlet of the tube and further includes an inner tube into which the second fluid flows,
The inner tube (inner tube),
It consists of a locking jaw formed at the front end to be caught on the inlet of the tube, a front end connected to the locking jaw, a center connected to the front end, and a rear end connected to the center,
The diameter of the front end and the rear end is greater than the diameter of the central portion, and is provided with a length from the inlet of the tube to any one point between 1/3 and 2/3 points,
The locking jaw is coupled by expansion or welding at the inlet of the tube,
The second fluid flowing into the front end of the inlet tube flows out from the rear end, and the leaked second fluid is heated by the high-temperature first fluid flowing into the shell to form a space between the inner tube and the tube. moving into space,
Additional heat exchange is made by the second fluid flowing out from the inner tube and flowing between the tube,
A dual tube type cylindrical shell-and-tube heat exchanger, characterized in that the distance between the first and second fluids increases from the center of the inner tube.
delete According to claim 1, wherein the inlet tube,
A dual tube type cylindrical shell-and-tube heat exchanger, characterized in that the length can be adjusted at the center. delete

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