KR20040074263A - Heat exchanger having multiful heat pipe - Google Patents

Abstract

PURPOSE: A multiple heat pipe type heat exchanger is provided to improve heat exchange efficiency by repeatedly evaporating and condensing plural kinds of actuating fluid with different boiling points in multiple heat pipes, and to manufacture the heat exchanger with compact structure. CONSTITUTION: A heat exchanger(100) is composed of a core pipe(110) formed with the specific diameter and length; plural pipes(120,130) formed to be shorter than the core pipe to contain the core pipes according to the diameter in regular sequence, and sealed and fixed to prevent the outer periphery of the pipe contained inside from being contacted to the inner periphery of the pipe for containing; and actuating fluid with different boiling points contained in plural fluid storage spaces of the pipes. The actuating fluid is arranged from the inner fluid storage space to the outer fluid storage space according to the boiling point. Wicks are formed in the outer periphery of the heat pipe, and cooling fins(140) are formed in the outer periphery of the outermost heat pipe to improve cooling efficiency.

Description

Multi Heat Pipe Type Heat Exchanger {HEAT EXCHANGER HAVING MULTIFUL HEAT PIPE}

The present invention relates to a heat pipe type heat exchanger, and more particularly, to a heat exchanger capable of compactly manufacturing heat exchange efficiency by using a multi-pipe heat pipe containing a working fluid having different boiling points.

HEAT PIPE is a working tube with a low boiling point and high latent heat of evaporation injected into a sealed vacuum metal tube. The heat pipe absorbs heat when the working fluid is vaporized and releases heat when it is liquefied. It is a device for transferring heat efficiently.

6 is a schematic view for explaining the operation principle of the heat pipe. As shown in FIG. 6, the heat pipe generally consists of a hollow metal tube 10 sealed at both ends, and a wick 11 (WICK) covers the inner surface of the tube 10. As shown in FIG. In addition, the inside of the tube is vacuum and a working fluid 20 such as distilled water is injected. When one end of the pipe is heated (Qin), the working fluid 20 evaporates at the heated end and moves to a cold end that is not heated to condense. At this time, the working fluid condenses at the cold end and releases heat (Qout). The heat dissipated and condensed working fluid is circulated to the heating end by the capillary phenomenon or gravity of the wick 11. That is, a cycle of absorbing heat while evaporating at the heating end and releasing heat while condensing at the cooling end is repeated, and this cycle becomes a basic principle of heat transfer of the heat pipe.

In the heat pipe, a metal such as Cu, Ni, or stainless steel having a high thermal conductivity is used as the tube, and a liquid having a low boiling point and a large latent heat of evaporation, such as distilled water or methanol, is used as the working fluid.

In the case of cooling fluids such as oil used in various hydraulic machines, injection machines, transformers, semiconductor equipment, and various heated liquids in chemical processes, water or air is often forcedly circulated to cool. In particular, when cooling by circulating the cooling water, the installation of piping for cooling water circulation was complicated and consumed a lot of power. In addition, if the pipe is damaged due to corrosion or freezing of the pipe, there is a problem that the operation of the equipment must be stopped for the pipe repair. In addition, when temperature control of the cooling water is required, additional equipment such as a cooling tower and a control device are required in order to adjust the amount of circulation and the temperature of the water, which causes the device to be more complicated.

The present invention is to solve the above problems, by using the principle of heat pipes with good heat transfer efficiency, a plurality of working fluids having different boiling points are repeatedly evaporated and condensed continuously to efficiently cool the fluid to be cooled It is an object of the present invention to provide a multiple heat pipe type heat exchanger.

Another object of the present invention is to provide a multiple heat pipe type heat exchanger having a wick formed on the outer circumferential surface of a plurality of heat pipes in order to increase the evaporation efficiency of the working fluid.

Another object of the present invention is to provide a multiple heat pipe type heat exchanger having cooling fins formed on the outer circumference of the outermost heat pipe in order to efficiently discharge heat to the atmosphere.

1 is a perspective view of one embodiment of a multiple heat pipe type heat exchanger in the present invention

2 is a cross-sectional view taken along the line A-A of FIG.

Figure 3a is a cross-sectional view taken along the line A-A of another embodiment of the present invention

3B is a schematic perspective view showing a state in which a groove is formed on a surface of a pipe according to another embodiment of the present invention.

4 is a state diagram used when using a multi-heat pipe type heat exchanger connected in series in accordance with the present invention

5 is a temperature-pressure diagram of a working fluid for explaining the principle of the multiple heat pipe type heat exchanger of the present invention.

6 is an explanatory diagram showing a principle of operation of a general heat pipe;

<Short description of symbols>

100 Chiller 110 Tube

111 Through Hole 112 Inlet

113 Exit 114 First Week

120 First heat pipe 121 First working fluid

124 Second Week 130 Second Heat Pipe

131 Second working fluid 140 Cooling fin

150, 160 support

The multi-heat pipe type heat exchanger according to the present invention includes a core pipe having a constant length and diameter and a core which is not larger in length than the core pipe and sequentially accommodates the core pipe in order of larger diameter, and is housed therein. A plurality of pipes sealed at both ends so that the outer circumference of the pipe and the inner circumference of the receiving pipe do not contact each other, and a working fluid having different boiling points contained in the plurality of fluid receiving spaces formed inside the plurality of pipes, The plurality of working fluids are sequentially arranged from the inner fluid receiving space to the outer fluid receiving space in the order of high boiling point.

According to the present invention, while the high-temperature fluid flows into the core pipe, the working fluid (first working fluid) contained in the fluid receiving space surrounding the outer circumference of the core pipe evaporates to cool the core pipe, and the fluid receiving The pipe (first heat pipe) surrounding the core pipe is heated while condensing in contact with the inner surface of the pipe surrounding the outside of the space. In addition, the working fluid (second working fluid) accommodated in the fluid receiving space surrounding the heated first heat pipe evaporates to cool the first heat pipe, the pipe surrounding the first heat pipe (second heat pipe Heating the second heat pipe while condensing on the inner circumferential surface of the At this time, since the boiling point of the second working fluid is lower than the boiling point of the first working fluid, the core pipe, the first heat pipe, and the second heat pipe can maintain the temperature near the boiling point when they are designed to have a suitable heat dissipation area. That is, in the case of using the heat exchanger of the present invention, evaporation and condensation occur continuously in each pipe, thereby enabling efficient heat exchange.

In addition, the multi-heat pipe type heat exchanger according to the present invention is characterized in that the centerlines of the plurality of pipes are positioned at a predetermined distance from the same direction with respect to the centerline of the core pipe on the same plane.

According to the present invention, a plurality of pipes are installed so as to be eccentric in the same direction, when the heat exchanger is installed horizontally so that the pipes are all submerged slightly in the working fluid to enable heat exchange by conduction and evaporation at the same time, The design of the capacity can be facilitated.

In addition, the multi-heat pipe type heat exchanger according to the present invention, the working fluid accommodated in the plurality of fluid receiving space is distilled water, the plurality of fluid receiving space is characterized in that the fluid receiving space located outside the core pipe has a higher vacuum pressure It is done.

5 is a pressure-temperature plot for the phase change of any material to illustrate the basic concepts of the present invention. As shown in FIG. 5, when the temperature of a liquid substance is raised under a constant pressure, a phase change from a liquid to a gas is made on the boundary of the evaporation curve v. At this time, if the pressure is high, the phase change at a higher temperature in the case of the same material. That is, if the temperature is increased at the pressure of P1, the liquid evaporates from the liquid state to the gas state along the a-a line, and the boiling temperature is T1. In addition, if the temperature is increased at the pressure of P2, the phase changes from the liquid state to the gas state along the b-b line, and the boiling temperature is T2. That is, in the case of the same material, the higher the absolute pressure, the higher the boiling temperature, and the lower the absolute pressure, the lower the boiling temperature. Therefore, according to the present invention, when the same material is used as the working fluid, the boiling temperature can be changed by appropriately adjusting the vacuum degree of the heat pipe.

In the multiple heat pipe type heat exchanger according to the present invention, a plurality of grooves having a constant depth around the circumference are formed on the outer circumference of the core pipe and the outer circumferential surface of the pipe accommodated therein among the plurality of pipes, or the core pipe The outer periphery of the, characterized in that it further comprises a porous pipe fitted to the outer peripheral surface of the pipe accommodated inside of the plurality of pipes.

According to the present invention, the working fluid is evenly moved to the circumferential surface of the pipe by the capillary phenomenon by the rolled portion or the porous pipe formed on the outer circumference of the pipe, thereby widening the evaporation area, thereby enabling more efficient heat exchange.

In addition, the multi-heat pipe type heat exchanger according to the present invention is characterized in that it further comprises a cooling fin is fixed to protrude in the radial direction on the outer circumferential surface of the pipe with the largest diameter among the plurality of pipes.

According to the present invention, it is possible to more efficiently conduct heat transfer by conduction and convection to the atmosphere by the cooling fins formed on the outer circumferential surface of the pipe having the largest diameter.

In addition, the multiple heat pipe type heat exchanger according to the present invention is characterized in that the diameter of the core pipe is 1/2 or less of the diameter of the plurality of pipes.

If the diameter of the heat pipe surrounding the core pipe is too small, the proper amount of the working fluid cannot be accommodated, and the condensation area cannot be sufficiently secured, thereby reducing the efficiency of heat exchange. Therefore, in order to properly receive the working fluid and secure the condensation area, the diameter of the plurality of pipes is preferably at least twice the diameter of the core pipe.

Hereinafter, with reference to the drawings will be described in detail a preferred embodiment of the present invention.

1 is a perspective view of one embodiment of a multiple heat pipe type heat exchanger according to the present invention, and FIG. 2 is a cross-sectional view taken along line A-A of FIG.

As shown in FIG. 1, the heat exchanger 100 according to the present embodiment includes a core pipe 110 having a predetermined length and diameter, and a plurality of pipes 120 that receive and wrap the core pipe 110 therein. 130 and a working fluid 121 and 131 accommodated in the plurality of pipes 120 and 130.

In the present embodiment, the plurality of pipes 120 and 130 have the same length, and the core pipe 110 is larger than the plurality of pipes 120 and 130. Therefore, the core pipe 110 has an inlet portion 111 and an outlet portion 113 to be connected to an external pipe, and a male screw 112 is formed on the outer circumference of the inlet portion 111 and the outlet portion 113. Therefore, it is easy to connect to external pipes. In addition, in the present exemplary embodiment, the plurality of pipes 120 and 130 may include a first heat pipe 120 surrounding the core pipe 110 and a second heat pipe 130 surrounding the first heat pipe 120. It consists of. In this embodiment, two heat pipes are used, but the number of heat pipes can be added according to the heat exchange capacity. In addition, the first and second heat pipes 120 and 130 are hermetically fixed at both ends so as not to contact the outer circumference of each pipe housed therein. In particular, the center lines of the core pipe 110, the first and second heat pipes 120 and 130 are coplanar and fixed at both ends so as to be spaced a predetermined distance in the same direction with respect to the center line of the core pipe 120. Is installed. Therefore, as shown in Figure 2, a plurality of pipes are installed so as to be eccentric in the same direction, when installing the heat exchanger horizontally the pipes are all submerged slightly in the working fluid, by the conduction and evaporation effect by the working fluid Heat exchange can be performed simultaneously between the core pipe and the heat pipe, and the evaporation area can be easily calculated, making it easy to design the heat exchange capacity.

In particular, the heat exchanger according to the present invention accommodates working fluids having different boiling points in a plurality of fluid receiving spaces formed in the plurality of pipes, and the plurality of working fluids have an inner fluid receiving space in a high boiling point order. It is characterized in that arranged sequentially from the outer side to the fluid receiving space. That is, the boiling point of the first working fluid 121 uses a working fluid higher than the boiling point of the second working fluid 131. Therefore, at the temperature at which the second working fluid evaporates, the first working fluid releases heat while condensing, thereby allowing heat exchange while simultaneously condensing and evaporating. In addition, by using a multi-pipe it is possible to manufacture a heat exchanger more compact than when using a double pipe, there is an advantage that can reduce the installation space. Distilled water, hydrocarbons, halogenated hydrocarbons, and the like are used as working fluids, but distilled water with less environmental impact is used in this embodiment. The injection amount of the working fluid varies depending on the diameter of the heat pipe, but it is usually desirable to determine that the center line portion of the heat pipe is not submerged within the range of 10% to 40% of the fluid receiving space.

In addition, in the heat exchanger 100 of the present embodiment, the cooling fins 140 are fixed to the outer circumferential surface of the second heat pipe 130 in a radial direction. Cooling fin 140 is preferably formed so as to be spiral along the longitudinal direction at regular intervals as shown in Figure 1 can be improved heat transfer efficiency.

3A is a cross-sectional view taken along line A-A of another embodiment of the present invention, and FIG. 3B is a schematic perspective view showing a state in which a groove is formed on the surface of a pipe according to another embodiment of the present invention.

The heat exchanger illustrated in FIG. 3A is characterized in that the porous pipe 124 of the porous material is fitted in close contact with the outer circumference of the core pipe 110 and the first heat pipe 120. The heat exchanger illustrated in FIG. The outer periphery of the pipe 110 and the first heat pipe 120 is characterized in that a plurality of grooves 115 having a constant depth around the circumference along the axial direction is formed. Therefore, the working fluid is evenly moved to the outer circumferential surface of the pipe by a capillary phenomenon by the rolled portion 115 or the porous pipe 124 formed on the outer circumference of the pipe, so that the evaporation area is widened, thereby enabling more efficient heat exchange. In particular, when the porous pipe 120 is installed, even if the heat exchanger is installed to be inclined to some extent, there is an advantage of preventing performance degradation of the heat exchanger.

4 is a state diagram used when using a multi-heat pipe type heat exchanger connected in series in accordance with the present invention. As shown in Figure 4, by using a plurality of heat exchangers of the present embodiment connected in series it is possible to increase the heat exchange capacity while saving space.

In the present embodiment, the fluid to be cooled flows through the inner through hole of the core pipe 110, but according to another aspect of the present invention, the external pipe is heated and the fluid flowing in the core pipe 110 is heated. You can also use it in reverse.

When the heat exchanger according to the present invention is used for heating the fluid flowing through the core pipe, the arrangement of the working fluid is arranged in the reverse order to that of the present embodiment, that is, in the order of low boiling point. In addition, the groove or the porous pipe may also be formed on the inner circumferential surface instead of the outer circumferential surface of the plurality of pipes, thereby increasing heat transfer efficiency from the external heat pipe to the internal core pipe by capillary action.

According to the present invention, by using the principle of heat pipe with good heat transfer efficiency, it is possible to provide a multiple heat pipe type heat exchanger including a plurality of working fluids having different boiling points, so that the evaporation and condensation can be repeated and efficiently cooled. It is possible to cool the fluid.

In addition, according to the present invention, it is possible to increase the efficiency of heat exchange by providing a multiple heat pipe type heat exchanger having a wick formed on the outer circumferential surface of the plurality of heat pipes.

In addition, according to the present invention, it is possible to further increase the cooling efficiency to the atmosphere by providing a multiple heat pipe type heat exchanger having a cooling fin formed on the outer circumference of the outermost heat pipe.

An embodiment of the present invention described above and illustrated in the drawings should not be construed as limiting the technical idea of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention, as will be apparent to those skilled in the art.

Claims (13)

Core pipe having a constant length and diameter, The plurality of cores are not larger than the core pipe, and the core pipes are sequentially accommodated in order of increasing diameter, and each of the plurality of seals fixed at both ends so that the outer circumference of the pipe accommodated therein and the inner circumference of the receiving pipe do not contact each other. With pipes, A working fluid having different boiling points contained in the plurality of fluid receiving spaces formed inside the plurality of pipes, The plurality of working fluid is a multiple heat pipe type heat exchanger, characterized in that arranged sequentially from the inner fluid receiving space to the outer fluid receiving space in the order of high boiling point. The method of claim 1, The center line of the plurality of pipes on the same plane, multiple heat pipe type heat exchanger, characterized in that spaced apart a predetermined distance in the same direction with respect to the center line of the core pipe. The method of claim 2, The working fluid accommodated in the plurality of fluid receiving spaces is distilled water, The plurality of fluid receiving space is a multiple heat pipe type heat exchanger, characterized in that the fluid receiving space located outside the core pipe has a higher vacuum pressure. The method according to any one of claims 1 to 3, And a plurality of grooves having a constant depth around the circumference of the core pipe and the outer circumferential surface of the pipe accommodated therein among the plurality of pipes. The method according to any one of claims 1 to 3, And a porous pipe fitted to an outer circumference of the core pipe and an outer circumferential surface of a pipe housed therein among the plurality of pipes. The method of claim 4, wherein Multiple heat pipe type heat exchanger characterized in that it further comprises a cooling fin is fixed to protrude in the radial direction on the outer peripheral surface of the pipe of the largest diameter of the plurality of pipes. The method of claim 5, Multiple heat pipe type heat exchanger characterized in that it further comprises a cooling fin is fixed to protrude in the radial direction on the outer peripheral surface of the pipe of the largest diameter of the plurality of pipes. The method according to claim 6 or 7, The diameter of the core pipe is a multiple heat pipe type heat exchanger, characterized in that less than 1/2 of the diameter of the plurality of pipes. Core pipe having a constant length and diameter, The plurality of cores are not larger than the core pipe, and the core pipes are sequentially accommodated in order of increasing diameter, and each of the plurality of seals fixed at both ends so that the outer circumference of the pipe accommodated therein and the inner circumference of the receiving pipe do not contact each other. With pipes, A working fluid having different boiling points contained in the plurality of fluid receiving spaces formed inside the plurality of pipes, The plurality of working fluid is a multiple heat pipe type heat exchanger, characterized in that arranged sequentially from the inner fluid receiving space to the outer fluid receiving space in the order of low boiling point. The method of claim 9, The center line of the plurality of pipes on the same plane, multiple heat pipe type heat exchanger, characterized in that spaced apart a predetermined distance in the same direction with respect to the center line of the core pipe. The method of claim 10, The working fluid accommodated in the plurality of fluid receiving spaces is distilled water, The plurality of fluid receiving space is a multiple heat pipe type heat exchanger, characterized in that the fluid receiving space located outside the core pipe has a lower vacuum pressure. The method according to any one of claims 9 to 11, And a plurality of grooves having a constant circumference around a circumference of the core pipe and an inner circumferential surface of the pipe accommodated therein among the plurality of pipes. The method according to any one of claims 9 to 11, Multiple heat pipe type heat exchanger further comprises a porous pipe fitted to the inner circumferential surface of the plurality of pipes.