WO2018061155A1

WO2018061155A1 - Heat pipe

Info

Publication number: WO2018061155A1
Application number: PCT/JP2016/078904
Authority: WO
Inventors: 博治小林; 廣田　寿一
Original assignee: 日本碍子株式会社
Priority date: 2016-09-29
Filing date: 2016-09-29
Publication date: 2018-04-05
Also published as: JP6714090B2; JPWO2018061155A1

Abstract

Provided is a heat pipe wherein heat can be efficiently transferred to a liquid working fluid. A heat pipe (1) is provided with: an inner cylinder (6); a cylindrical wick (2) formed of a porous ceramic, said wick covering the outer circumferential surface of the inner cylinder (6); and a cylindrical case (3) covering the outer circumferential surface of the wick (2). A plurality of liquid flow channels (51) and a plurality of gas flow channels (52) are formed in the wick (2), said liquid flow channels and gas flow channels extending in the axis direction.

Description

heat pipe

The technology disclosed in this specification relates to a heat pipe.

A heat pipe disclosed in Patent Document 1 (Japanese Unexamined Patent Publication No. 2014-70871) covers an inner cylinder, a porous wick that covers the outer peripheral surface of the inner cylinder, and an outer peripheral surface of the wick. And a cylindrical case. A plurality of liquid flow paths extending in the axial direction are formed in the wick, and a liquid working fluid flows through these liquid flow paths. Further, a plurality of gas flow paths are formed between the inner cylinder and the wick and between the wick and the case, and a gas working fluid flows through these gas flow paths.

In the heat pipe of Patent Document 1, when the thermal fluid flows through the hollow portion inside the inner cylinder, the heat of the thermal fluid is transmitted to the wick. Further, in this heat pipe, when the liquid working fluid flows through the liquid flow path, the working fluid penetrates into the porous wick by capillary action. The liquid working fluid that has permeated the wick receives the heat transferred from the thermal fluid to the wick, evaporates, and changes its state to a gaseous working fluid. The evaporated working fluid flows into the gas channel from the wick and flows through the gas channel.

In the heat pipe, it is preferable to efficiently heat the liquid working fluid to change the state to a gaseous working fluid. For this purpose, it is preferable to efficiently transfer heat from the wick to the liquid working fluid. Conventional heat pipes are insufficient in this respect. Therefore, the present specification provides a technique capable of efficiently transferring heat to a liquid working fluid.

A heat pipe disclosed in the present specification includes an inner cylinder, a cylindrical wick formed of porous ceramics covering the outer peripheral surface of the inner cylinder, and a cylindrical case covering the outer peripheral surface of the wick. And. The wick is formed with a plurality of liquid channels and a plurality of gas channels extending in the axial direction.

According to such a configuration, when the thermal fluid flows through the hollow portion inside the inner cylinder, the heat of the thermal fluid is transmitted to the wick. The heat of the thermal fluid diffuses from the inner cylinder to the surroundings. Since the inner cylinder exists inside the wick, the heat of the thermal fluid diffusing around can be efficiently transferred to the wick. Further, according to the above configuration, when the liquid working fluid flows through the liquid flow path, the working fluid penetrates into the porous wick by capillary action. The liquid working fluid that has permeated the wick receives the heat transferred from the thermal fluid to the wick, evaporates, and changes its state to a gaseous working fluid. The evaporated working fluid flows into the gas channel and flows through the gas channel. According to the above configuration, since the liquid flow path and the gas flow path are formed in the wick, the working fluid that has penetrated from the liquid flow path into the wick and evaporated flows smoothly into the gas flow path. Since the working fluid flows smoothly from the wick liquid flow path to the gas flow path, heat can be efficiently transferred from the wick to the liquid working fluid.

Further, the above heat pipe may include a heat transfer member disposed inside the inner cylinder. The end of the heat transfer member may be fixed to the inner peripheral surface of the inner cylinder.

According to such a configuration, the heat of the thermal fluid flowing through the hollow portion inside the inner cylinder can be easily transmitted to the inner cylinder via the heat transfer member.

In the above heat pipe, the inner cylinder may be formed of a brazing material.

According to such a configuration, heat can be easily transferred from the inner cylinder to the wick.

In the above heat pipe, the heat transfer member may be formed of Si-impregnated SiC.

According to such a configuration, the heat of the thermal fluid can be further easily transmitted to the inner cylinder.

In the above heat pipe, the wick includes a porous cylindrical body, and a plurality of porous wall bodies that extend in the axial direction of the cylindrical body in the internal space of the cylindrical body and partition the internal space. May be. A liquid channel and a gas channel that extend in the axial direction may be formed in the internal space by partitioning the internal space with a plurality of wall bodies. The liquid channel may be open at one end in the axial direction and sealed at the other end. The gas flow path may be sealed at one end in the axial direction and open at the other end.

According to such a configuration, since the porous wall body that forms the liquid flow path and the gas flow path is provided in the internal space of the wick cylinder, the liquid working fluid flowing in the liquid flow path is subjected to capillary action. Infiltrate the wall from the liquid flow path. The liquid working fluid that has permeated the wall body receives heat from the wall body, evaporates, and changes its state to a gaseous working fluid. The evaporated working fluid flows from the wall into the gas flow path and flows through the gas flow path. According to such a configuration, since the wick includes the wall body, the portion where the liquid working fluid comes into contact with the wick increases, and the portion that can receive heat from the wick increases. Therefore, heat can be efficiently transferred to the liquid working fluid. By combining the configuration in which the inner cylinder is present inside the wick and the configuration in which the wick includes a wall body, heat can be more efficiently transferred to the liquid working fluid.

It is a figure which shows schematic structure of an Example heat pipe. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a sectional view taken along the line III-III in FIG. 2. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. It is a figure which shows schematic structure of a loop heat pipe. It is sectional drawing corresponding to FIG. 4 of another Example. Furthermore, it is sectional drawing corresponding to FIG. 4 of another Example. It is sectional drawing of the liquid flow path and gas flow path of another Example. Furthermore, it is sectional drawing corresponding to FIG. 4 of another Example. Furthermore, it is sectional drawing corresponding to FIG. 4 of another Example.

Hereinafter, examples will be described with reference to the accompanying drawings. As shown in FIGS. 1 to 3, the heat pipe 1 according to the embodiment includes an inner cylinder 6, a wick 2, and a case 3. The heat pipe 1 is a device that transfers heat using a working fluid.

The inner cylinder 6 is formed from a brazing material. Examples of the brazing material include gold brazing, silver brazing, copper brazing, and aluminum brazing. A method for forming the inner cylinder 6 made of brazing material is, for example, by applying a paste brazing material mixed with a mixed powder of Ag—Cu—In alloy powder and Ti powder, an organic solvent and a resin to the inner peripheral surface of the wick 2. There is a method of drying later. The specific composition of the brazing material is preferably Ag 30 to 60%, Cu 20 to 45%, In 20 to 40%, and Ti 0.5 to 5%. As an element constituting the brazing material, one or more of Sn, Al, Zn, Cd, Ni, P and Mn may be contained in addition to Ag and Cu. The thermal fluid flows through the hollow portion 61 inside the inner cylinder 6. The thermal fluid is exhaust gas discharged from the automobile. The heat of the thermal fluid is transmitted to the wick 2 through the inner cylinder 6.

The heat transfer member 8 is disposed in the hollow portion 61 inside the inner cylinder 6. The end of the heat transfer member 8 is fixed to the inner peripheral surface of the inner cylinder 6. Examples of the material of the heat transfer member 8 include metals and ceramics. The heat transfer member 8 is preferably formed from Si-impregnated SiC (silicon-impregnated silicon carbide).

The heat transfer member 8 includes a plurality of wall bodies 82. The plurality of wall bodies 82 are disposed in the hollow portion 61 inside the inner cylinder 6. As shown in FIG. 2, in a cross section orthogonal to the axial direction (x direction) of the inner cylinder 6, a plurality of wall bodies 82 arranged at equal intervals in the horizontal direction (y direction) and the vertical direction (z direction). There are a plurality of wall bodies 82 arranged at equal intervals. In the cross section orthogonal to the axial direction (x direction) of the inner cylinder 6, both end portions of each wall body 82 are fixed to the inner peripheral surface of the inner cylinder 6. The plurality of wall bodies 82 and the inner cylinder 6 are integrally formed to form a honeycomb structure. The plurality of wall bodies 82 arranged in the horizontal direction and the vertical direction are combined in a lattice shape and are integrally formed. The plurality of wall bodies 82 partitions the hollow portion 61 inside the inner cylinder 6 in directions (y direction and z direction) orthogonal to the axial direction (x direction) of the inner cylinder 6.

As shown in FIG. 3, the plurality of wall bodies 82 extend in the axial direction (x direction) in a cross section parallel to the axial direction (x direction) of the inner cylinder 6. The plurality of wall bodies 82 extend from one end portion in the axial direction (x direction) of the inner cylinder 6 to the other end portion.

The cylindrical wick 2 covers the outer peripheral surface of the inner cylinder 6 and is fixed to the outer peripheral surface of the inner cylinder 6. The outer peripheral surface of the inner cylinder 6 is in close contact with the inner peripheral surface of the wick 2. The wick 2 includes a wick cylinder 21 and a plurality of wall bodies 22. The wick cylinder 21 is made of a porous material such as ceramics. An internal space 70 is formed inside the wick cylinder 21. The wick cylinder 21 is formed in a cylindrical shape.

The plurality of wall bodies 22 are formed of a porous material such as ceramics, for example, similarly to the wick cylinder 21. The plurality of wall bodies 22 are arranged in the cylindrical internal space 70 of the wick cylinder 21. As shown in FIG. 2, in the cross section orthogonal to the axial direction (x direction) of the wick cylinder 21, a plurality of wall bodies 22 arranged at equal intervals in the horizontal direction (y direction) and the vertical direction (z direction) There are a plurality of wall bodies 22 arranged at equal intervals. In the cross section orthogonal to the axial direction (x direction) of the wick cylinder 21, both end portions of each wall body 22 are fixed to the inner peripheral surface of the wick cylinder 21. The plurality of wall bodies 22 and the wick cylinder 21 are integrally formed to form a honeycomb structure. The plurality of wall bodies 22 arranged in the horizontal direction and the vertical direction are combined in a lattice shape and are integrally formed.

The plurality of wall bodies 22 divide the internal space 70 of the wick cylinder 21 in directions (y direction and z direction) orthogonal to the axial direction (x direction) of the wick cylinder 21. The plurality of wall bodies 22 divide the internal space 70, so that a plurality of liquid flow paths 51 and a plurality of gas flow paths 52 are formed in the internal space 70. In the example shown in FIG. 2, eight liquid channels 51 and 20 gas channels 52 are formed. A plurality of liquid flow paths 51 are formed at the center of the internal space 70, and a plurality of gas flow paths 52 are formed at the peripheral edge of the internal space 70. A plurality of liquid flow paths 51 are formed inside the plurality of gas flow paths 52. In the example shown in FIG. 2, each of the eight inner spaces constitutes a liquid flow path 51, and each of the twenty outer spaces constitutes a gas flow path 52. A liquid working fluid flows through the liquid channel 51, and a gas working fluid flows through the gas channel 52.

In the cross section orthogonal to the axial direction of the wick cylinder 21, the liquid flow path 51 is surrounded by the plurality of wall bodies 22 and is in contact with the plurality of wall bodies 22. The liquid flow path 51 is not in contact with the wick cylinder 21. The gas flow path 52 is surrounded by the plurality of wall bodies 22 and the wick cylinder body 21, and is in contact with the plurality of wall bodies 22 and the wick cylinder body 21. Of the plurality of wall bodies 22, the wall body 22 arranged in the central portion of the internal space 70 is referred to as a central wall body 22 a. The central wall 22a passes through the central portion of the internal space 70.

As shown in FIG. 3, the plurality of wall bodies 22 extend in the axial direction (x direction) in a cross section parallel to the axial direction (x direction) of the wick cylinder 21. The plurality of wall bodies 22 extend from one end portion in the axial direction (x direction) of the wick cylinder 21 to the other end portion. The plurality of liquid channels 51 and the plurality of gas channels 52 extend in the axial direction (x direction). The plurality of liquid channels 51 and the plurality of gas channels 52 extend from one end of the wick cylinder 21 in the axial direction (x direction) to the other end. The liquid flow channel 51 is open at one end in the axial direction of the wick cylinder 21 and is sealed at the other end by the first sealing body 41. In the gas flow path 52, one end portion in the axial direction of the wick cylinder 21 is sealed by the second sealing body 42, and the other end portion is opened. As shown in FIG. 4, a plurality of liquid flow paths 51 are closed at the other axial end of the wick cylinder 21 (the liquid working fluid outlet side). On the other hand, although not shown, the plurality of gas flow paths 52 are closed at one end of the wick cylinder 21 in the axial direction (the inlet side of the liquid working fluid). The first sealing body 41 and the second sealing body 42 are integrated with the wick cylinder 21 and the plurality of wall bodies 22.

As shown in FIG. 3, the case 3 includes a case cylinder 32 and a pair of lids 31. The case cylinder 32 and the pair of lid bodies 31 are made of a metal material such as copper (Cu), for example. The case cylinder 32 is formed in a cylindrical shape. The case cylinder 32 may be formed in a square cylinder shape. The shape of the case cylinder 32 in the cross section orthogonal to the axial direction (x direction) of the case cylinder 32 is not particularly limited. The case cylinder 32 is disposed outside the wick cylinder 21. The case cylinder 32 covers the wick cylinder 21. The inner peripheral surface of the case cylinder 32 is in close contact with the outer peripheral surface of the wick cylinder 21. The pair of lids 31 are fixed to both ends of the case cylinder 32. The pair of lids 31 seals the case cylinder 32.

Next, the loop heat pipe 101 including the heat pipe 1 will be described. As shown in FIG. 5, the loop heat pipe 101 includes an evaporator 111, a steam pipe 122, a condenser 112, and a liquid pipe 121. The evaporator 111, the steam pipe 122, the condenser 112, and the liquid pipe 121 are connected so as to form a loop. The loop heat pipe 101 includes a reservoir 125 and an exhaust gas pipe 126.

The evaporator 111 is constituted by the heat pipe 1 described above. In the evaporator 111, the liquid working fluid is heated and evaporated, and the state changes to a gaseous working fluid. The working fluid receives heat in the evaporator 111. The evaporator 111 is a device that heats the working fluid.

An exhaust gas pipe 126 is connected to the evaporator 111 (heat pipe 1). The exhaust gas pipe 126 guides the exhaust gas discharged from the automobile to the evaporator 111. Exhaust gas discharged from automobiles is used as a thermal fluid. Thermal fluid (exhaust gas) flows in the exhaust gas pipe 126. The exhaust gas pipe 126 is connected to the inner cylinder 6 (not shown in FIG. 5) of the heat pipe 1. The thermal fluid (exhaust gas) that has flowed through the exhaust gas pipe 126 flows into the hollow portion 61 inside the inner cylinder 6.

In the condenser 112, the gaseous working fluid is cooled and condensed, and the state changes to a liquid working fluid. The working fluid dissipates heat in the condenser 112. The condenser 112 is a device that receives heat from the working fluid.

The liquid pipe 121 guides the liquid working fluid from the condenser 112 to the evaporator 111. The upstream end of the liquid pipe 121 is connected to the condenser 112, and the downstream end is connected to the evaporator 111. A liquid working fluid flows in the liquid pipe 121.

The steam pipe 122 guides the gaseous working fluid from the evaporator 111 to the condenser 112. The upstream end of the steam pipe 122 is connected to the evaporator 111, and the downstream end is connected to the condenser 112. A gaseous working fluid flows in the vapor pipe 122.

The reservoir 125 is installed in the liquid pipe 121. A part of the liquid working fluid flowing through the liquid pipe 121 is stored. Thus, the flow rate of the liquid working fluid flowing from the liquid pipe 121 to the evaporator 111 is adjusted.

Next, the operation of the loop heat pipe 101 will be described. In the loop heat pipe 101, the exhaust gas flowing through the exhaust gas pipe 126 is introduced from the exhaust gas pipe 126 into the evaporator 111. That is, the thermal fluid is introduced from the exhaust gas pipe 126 into the heat pipe 1. The thermal fluid is introduced into the hollow portion 61 inside the inner cylinder 6 of the heat pipe 1. The heat of the thermal fluid introduced into the hollow portion 61 is transmitted to the wick 2 through the heat transfer member 8 and the inner cylinder 6 disposed in the hollow portion 61. The wick 2 is heated by the heat of the thermal fluid. The wick cylinder 21 and the wall 22 of the wick 2 are heated by the heat of the thermal fluid. In this state, the liquid working fluid that has flowed through the liquid pipe 121 is introduced from the liquid pipe 121 into the evaporator 111. That is, a liquid working fluid is introduced from the liquid pipe 121 to the heat pipe 1. The liquid working fluid introduced into the heat pipe 1 flows into the plurality of liquid flow paths 51 formed in the internal space 70 of the wick cylinder 21 and flows through the liquid flow path 51. The liquid working fluid flowing through the liquid channel 51 penetrates into the porous wall body 22 by capillary action.

When the liquid working fluid penetrates into the porous wall body 22, it receives heat from the wall body 22 and evaporates, and changes its state to a gaseous working fluid. The evaporated working fluid flows into the plurality of gas flow paths 52 from the porous wall body 22 and flows through the gas flow paths 52. The gaseous working fluid that has flowed through the gas flow path 52 flows out of the heat pipe 1 and flows into the steam pipe 122. That is, a gaseous working fluid flows into the vapor pipe 122 from the evaporator 111.

The gaseous working fluid that has flowed into the steam pipe 122 flows through the steam pipe 122 and is introduced into the condenser 112 from the steam pipe 122. The gaseous working fluid introduced into the condenser 112 is condensed by releasing heat in the condenser 112, and changes to a liquid working fluid. The condensed liquid working fluid flows into the liquid pipe 121 from the condenser 112 and flows through the liquid pipe 121 again. Then, the liquid working fluid that has flowed through the liquid pipe 121 is again introduced into the heat pipe 1 from the liquid pipe 121. In this way, the working fluid flows through the loop heat pipe 101 while changing its state between the liquid and the gas. Heat is transported by the working fluid.

As is clear from the above description, the heat pipe 1 according to the embodiment includes an inner cylinder 6, a cylindrical wick 2 formed of porous ceramics covering the outer peripheral surface of the inner cylinder 6, and a wick. And a cylindrical case 3 covering the outer peripheral surface of 2. A plurality of liquid flow paths 51 and a plurality of gas flow paths 52 extending in the axial direction are formed in the wick 2. According to such a configuration, since the inner cylinder 6 exists inside the wick 2, the heat of the thermal fluid diffusing from the inner cylinder 6 to the surroundings can be efficiently transmitted to the wick 2. Further, since the liquid flow path 51 and the gas flow path 52 are formed in the wick 2, the working fluid that has permeated from the liquid flow path 51 into the wick 2 and evaporated flows smoothly into the gas flow path 52. Since the working fluid smoothly flows from the liquid channel 51 of the wick 2 to the gas channel 52, heat can be efficiently transferred from the wick 2 to the liquid working fluid.

In the heat pipe 1 described above, the inner cylinder 6 is formed of a brazing material. Therefore, when the inner cylinder 6 is thermally expanded, the pressure of the inner cylinder 6 and the wick 2 becomes an appropriate pressure. Heat can be easily transferred to 2. The thermal resistance between the inner cylinder 6 and the wick 2 becomes an appropriate thermal resistance. If the inner cylinder 6 is formed of other materials, the pressure of the inner cylinder 6 and the wick 2 may be too high or too low when the inner cylinder 6 is thermally expanded.

Further, the heat pipe 1 includes a heat transfer member 8 arranged inside the inner cylinder 6. The end of the heat transfer member 8 is fixed to the inner peripheral surface of the inner cylinder 6. The heat of the thermal fluid flowing through the hollow portion 61 inside the inner cylinder 6 is transmitted to the inner cylinder 6 via the heat transfer member 8. The heat of the thermal fluid can be easily transferred to the inner cylinder 6 by the heat transfer member 8. Further, when the heat transfer member 8 is made of Si-impregnated SiC, the heat conductivity is high, and the heat transfer member 8 can be easily transferred to the inner cylinder 6. Moreover, the tolerance with respect to exhaust gas can be made high.

As is clear from the above description, the wick 2 according to the embodiment includes the porous wall body 22 that forms the liquid channel 51 and the gas channel 52 in the internal space 70 of the wick cylinder 21. As a result, the liquid working fluid flowing through the liquid channel 51 permeates from the liquid channel 51 into the porous wall body 22 by capillary action. The liquid working fluid that has permeated the wall body 22 receives heat from the wall body 22 and evaporates, and changes its state to a gaseous working fluid. The evaporated working fluid flows into the gas channel 52 from the porous wall body 22 and flows through the gas channel 52. According to such a configuration, since the portion where the liquid working fluid is in contact with the wick 2 is increased by providing the wall body 22, the liquid working fluid can easily receive heat from the wick 2. Thereby, heat can be efficiently transferred from the wick 2 to the liquid working fluid. By combining the configuration in which the inner cylinder 6 exists inside the wick 2 and the configuration in which the wick 2 includes the wall body 22, heat can be more efficiently transferred to the liquid working fluid.

Further, according to the above configuration, the liquid flow path 51 is surrounded by the plurality of wall bodies 22 and is not in contact with the wick cylinder 21, so that the wall body against the liquid working fluid flowing through the liquid flow path 51. The heat can be efficiently transferred from 22.

As mentioned above, although one Example was described, a specific aspect is not limited to the said Example. In the following description, the same components as those described above are denoted by the same reference numerals and description thereof is omitted.

In the above embodiment, the plurality of liquid flow paths 51 are formed in the central portion of the internal space 70 and the plurality of gas flow paths 52 are formed in the peripheral edge of the internal space 70. However, the present invention is limited to this configuration. It is not something. In another embodiment, as shown in FIG. 6, the liquid channel 51 and the gas channel 52 may be alternately formed in a cross section orthogonal to the axial direction (x direction) of the wick cylinder 21. The plurality of liquid channels 51 and the plurality of gas channels 52 may be formed in a checkered pattern. Moreover, as shown in FIG. 7, in the cross section orthogonal to the axial direction (x direction) of the wick cylinder 21, a plurality of liquid flow paths 51 and a plurality of gas flow paths 52 are alternately formed for each row. Also good.

Further, as shown in FIG. 8, the cross-sectional area of each liquid channel 51 may be larger than the cross-sectional area of each gas channel 52 in a cross section orthogonal to the axial direction (x direction) of the wick cylinder 21. Further, the total cross-sectional area of the plurality of liquid flow paths 51 may be larger than the total cross-sectional area of the plurality of gas flow paths 52. According to such a configuration, the resistance when the liquid working fluid flows through the liquid channel 51 can be reduced. Since the liquid working fluid flows smoothly, the working fluid can be efficiently introduced into the wick 2.

In the above embodiment, the wick cylinder 21 is formed in a cylindrical shape, but is not limited to this configuration. The shape of the wick cylinder 21 in the cross section orthogonal to the axial direction (x direction) of the wick cylinder 21 is not particularly limited. In another embodiment, as shown in FIG. 9, the wick cylinder 21 may be formed in a square cylinder shape. In FIG. 9, the shape of the cross section orthogonal to the axial direction (x direction) of the wick cylinder 21 is a rectangle. In the cross section shown in FIG. 9, the wick cylinder 21 is formed so that the upper side and the lower side of the wick cylinder 21 are longer than the side. The upper side and the lower side of the wick cylinder 21 are long sides, and the side sides are short sides.

In the above embodiment, the inner cylinder 6 is formed in a cylindrical shape, but is not limited to this configuration. The shape of the inner cylinder 6 in the cross section orthogonal to the axial direction (x direction) of the inner cylinder 6 is not particularly limited. In another embodiment, as shown in FIG. 9, the inner cylinder 6 may be formed in a square cylinder shape. In FIG. 9, the cross-sectional shape orthogonal to the axial direction (x direction) of the inner cylinder 6 is a rectangle. In the cross section shown in FIG. 9, the inner cylinder 6 is formed such that the upper side and the lower side of the inner cylinder 6 are longer than the side sides. The upper side and the lower side of the inner cylinder 6 are long sides, and the side sides are short sides.

In still another embodiment, as shown in FIG. 10, the plurality of wall bodies 22 may be arranged concentrically and radially in a cross section orthogonal to the axial direction of the wick cylinder 21. In the cross section shown in FIG. 10, the plurality of wall bodies 22 arranged concentrically are arranged concentrically with the wick cylinder 21. The plurality of wall bodies 22 extend in the circumferential direction of the wick cylinder 21. In the cross section shown in FIG. 10, the plurality of wall bodies 22 arranged radially extend from the center of the internal space 70 in the radial direction of the wick cylinder 21. In the plurality of radial walls 22, heat is quickly transmitted to the center of the internal space 70.

In yet another embodiment, as shown in FIG. 10, a plurality of wall bodies 82 may be arranged concentrically and radially in a cross section orthogonal to the axial direction of the inner cylinder 6. In the cross section shown in FIG. 10, the plurality of wall bodies 82 arranged concentrically are arranged concentrically with the inner cylinder 6. The plurality of wall bodies 82 extend in the circumferential direction of the inner cylinder 6. Further, in the cross section shown in FIG. 10, the plurality of radially arranged wall bodies 82 extend from the center portion of the hollow portion 61 in the radial direction of the inner cylinder 6.

Next, an example of a manufacturing method of the wick 2 will be described. When the wick 2 is manufactured, first, water and a binder are added to the ceramic raw material powder and kneaded to prepare a kneaded clay having plasticity. Next, the prepared dough is extruded to form a honeycomb structure. As a result, a honeycomb structure including the wick cylinder 21 and the plurality of wall bodies 22 is formed.

Next, a sheet is attached to one end face of the honeycomb structure, and a hole is made in a part of the sheet (a position corresponding to the end of the gas flow path 52). In this state, one end surface of the honeycomb structure is immersed in a slurry containing a material of the sealing body (the first sealing body 41 and the second sealing body 42 described above). Thereafter, the material of the sealing body is cured by drying and baking, whereby the second sealing body 42 that seals the end of the gas flow path 52 is formed. Similarly to the above, a sheet is attached to the other end surface of the honeycomb structure, and a hole is formed in a part of the sheet (a position corresponding to the end of the liquid flow channel 51). In this state, the other end surface of the honeycomb structure is immersed in a slurry containing the material of the sealing body. Then, the 1st sealing body 41 which seals the edge part of the liquid flow path 51 is formed by hardening the material of a sealing body by drying and baking. In addition, each of the one end surface and the other end surface of the honeycomb structure is immersed in a slurry containing the material of the sealing body, and then dried and fired, whereby the second sealing body 42 and the first sealing body. 41 may be formed simultaneously.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

1: Heat pipe 2: Wick 3: Case 6: Inner cylinder 8: Heat transfer member 21: Wick cylinder 22: Wall body 22a: Central wall body 31: Lid body 32: Case cylinder body 41: First sealing body 42: 2nd sealing body 51: Liquid flow path 52: Gas flow path 61: Hollow part 70: Internal space 82: Wall body 101: Loop heat pipe 111: Evaporator 112: Condenser 121: Liquid pipe 122: Steam Pipe 125: Reservoir 126: Exhaust gas pipe

Claims

An inner cylinder,
A cylindrical wick formed of porous ceramic covering the outer peripheral surface of the inner cylinder;
A cylindrical case covering the outer peripheral surface of the wick, and
A heat pipe in which a plurality of liquid flow paths and a plurality of gas flow paths extending in the axial direction are formed in the wick.
A heat transfer member disposed inside the inner cylinder;
The heat pipe according to claim 1, wherein an end portion of the heat transfer member is fixed to an inner peripheral surface of the inner cylinder.
The heat pipe according to claim 2, wherein the inner cylinder is formed of a brazing material.
The heat pipe according to any one of claims 1 to 3, wherein the heat transfer member is made of Si-impregnated SiC.
The wick includes a porous cylinder and a plurality of porous walls extending in the axial direction of the cylinder in the internal space of the cylinder and partitioning the internal space.
A liquid channel and a gas channel extending in the axial direction by the plurality of wall bodies partitioning the internal space are formed in the internal space,
The liquid channel has one end in the axial direction opened and the other end sealed.
The heat pipe according to any one of claims 1 to 4, wherein the gas flow path is sealed at one end in the axial direction and opened at the other end.