JP2021025730A - Heat exchanger - Google Patents

Abstract

To provide a heat exchanger enabling expansion pressure generated when a heating medium in a heating medium flow passage is frozen to be easily released from an inflow port or an outflow port to outside.SOLUTION: A heating medium flow passage R2 of a heat exchanger 10 is formed to have a U-shape comprising an inflow passage 14a having an inflow port 15a, an outflow passage 14b having an outflow port 15b and a communication passage 13 communicating the inflow passage 14a with the outflow passage 14b. The heat exchanger includes a partition wall 12d that partitions a space between the inflow passage 14a and the outflow passage 14b and constitutes a wall part of the communication passage 13. Each of a flow passage cross sectional area A1 of the inflow passage 14a and a flow passage cross sectional area A2 of the outflow passage 14b is set larger than a flow passage cross sectional area A3 of the communication passage 13.SELECTED DRAWING: Figure 5

Description

本発明は、セラミック製の熱交換器に関する。 The present invention relates to a ceramic heat exchanger.

特許文献１に開示される熱交換器は、ガス流通路と、熱媒体流通路と、ガス流通路及び熱媒体流通路を区画する区画壁とを備えるセラミック製のハニカム構造体により構成され、ガス流通路を流通するガスと、熱媒体流通路を流通する液状の熱媒体との間で熱交換を行う。特許文献１の熱交換器の熱媒体流通路は、外部に開口する流入路及び流出路と、流入路と流出路とを連通する複数のセルとから構成されている。 The heat exchanger disclosed in Patent Document 1 is composed of a gas honeycomb structure including a gas flow passage, a heat medium flow passage, and a partition wall for partitioning the gas flow passage and the heat medium flow passage, and is composed of a gas. Heat exchange is performed between the gas flowing through the flow passage and the liquid heat medium flowing through the heat medium flow passage. The heat medium flow path of the heat exchanger of Patent Document 1 is composed of an inflow path and an outflow path that open to the outside, and a plurality of cells that communicate the inflow path and the outflow path.

特開２０１５−１４０２７３号公報JP-A-2015-140273

ところで、特許文献１の熱交換器を、内部に熱媒体が溜まった状態として熱媒体が凍結する条件に曝した場合、流入路と流出路とを連通する各セル内の熱媒体が凍結した際の膨張圧によって、流入路と流出路とを連通する各セルを区画する区画壁が損傷する虞があった。上記問題を解決する熱交換器として、図１３〜１５に示す構造の熱交換器４０を作製したところ、以下に記載する問題が新たに生じた。 By the way, when the heat exchanger of Patent Document 1 is exposed to a condition in which the heat medium is frozen with the heat medium accumulated inside, when the heat medium in each cell communicating the inflow path and the outflow path is frozen. There was a risk that the partition wall partitioning each cell communicating the inflow path and the outflow path would be damaged by the expansion pressure of. When the heat exchanger 40 having the structure shown in FIGS. 13 to 15 was manufactured as a heat exchanger to solve the above problems, the following problems were newly generated.

熱交換器４０の熱媒体流通路Ｒ２は、熱媒体を貯留する貯留部４１と、流入口４２と貯留部４１とを連通する流入路４３と、流出口４４と貯留部４１とを連通する流出路４５とを備えている。この場合、流入路４３と流出路４５とを連通する狭いセルが存在しないため、貯留部４１内の熱媒体が凍結した際に生じる膨張圧を流入路４３又は流出路４５に容易に逃がすことができる。しかしながら、貯留部４１内の熱媒体が凍結する前に、流入路４３内及び流出路４５内の熱媒体が凍結して流入路４３及び流出路４５が共に塞がれた閉塞状態になり、貯留部４１内の熱媒体が凍結した際の膨張圧を流入路４３又は流出路４５を通じて外部へ逃がすことができなくなってしまった。 The heat medium flow passage R2 of the heat exchanger 40 has a storage unit 41 that stores the heat medium, an inflow passage 43 that communicates the inflow port 42 and the storage unit 41, and an outflow that communicates the outflow port 44 and the storage unit 41. It has a road 45. In this case, since there is no narrow cell communicating the inflow passage 43 and the outflow passage 45, the expansion pressure generated when the heat medium in the storage portion 41 freezes can be easily released to the inflow passage 43 or the outflow passage 45. it can. However, before the heat medium in the storage unit 41 freezes, the heat medium in the inflow passage 43 and the outflow passage 45 freezes, and both the inflow passage 43 and the outflow passage 45 are blocked and stored. The expansion pressure when the heat medium in the section 41 freezes cannot be released to the outside through the inflow passage 43 or the outflow passage 45.

本発明は、こうした事情に鑑みてなされたものであり、その目的は、熱媒体流通路内の熱媒体が凍結した際に生じる膨張圧が流入口又は流出口から外部へ逃げやすい熱交換器を提供することにある。 The present invention has been made in view of these circumstances, and an object of the present invention is to provide a heat exchanger in which the expansion pressure generated when the heat medium in the heat medium flow path freezes easily escapes to the outside from the inlet or outlet. To provide.

上記課題を解決する熱交換器は、ガス流通路と、熱媒体流通路と、上記ガス流通路及び上記熱媒体流通路を区画する区画壁とを備え、上記ガス流通路を流通するガスと、上記熱媒体流通路を流通する液状の熱媒体との間で熱交換が行われるセラミック製の熱交換器であって、上記熱媒体流通路は、流入口を有する流入路と、流出口を有する流出路と、上記流入路と上記流出路とを連通する連通路とを備えるＵ字状に形成され、上記区画壁は、上記流入路と上記流出路との間を仕切るとともに上記連通路の壁面を構成する仕切壁を備え、上記流入路の熱媒体流通方向における断面積及び上記流出路の熱媒体流通方向における断面積の少なくとも一方は、上記連通路の熱媒体流通方向における断面積よりも大きい。 A heat exchanger that solves the above problems includes a gas flow passage, a heat medium flow passage, and a partition wall that partitions the gas flow passage and the heat medium flow passage, and the gas flowing through the gas flow passage and the gas. A ceramic heat exchanger in which heat is exchanged with a liquid heat medium flowing through the heat medium flow path, and the heat medium flow path has an inflow path having an inflow port and an outflow port. It is formed in a U shape including an outflow passage and a communication passage that connects the inflow passage and the outflow passage, and the partition wall partitions the inflow passage and the outflow passage and is a wall surface of the communication passage. At least one of the cross-sectional area of the inflow path in the heat medium flow direction and the cross-sectional area of the outflow path in the heat medium flow direction is larger than the cross-sectional area of the communication passage in the heat medium flow direction. ..

上記構成の熱交換器を、熱媒体流通路内に液状の熱媒体が溜まった状態として熱媒体が凍結する条件に曝すと、熱媒体流通路内の熱媒体が徐々に凍結していく。このとき、流路断面積が大きい流入路及び流出路では、内部の熱媒体が完全に凍結するまでに要する時間が長くなり、流路断面積が小さい連通路では、内部の熱媒体が完全に凍結するまでに要する時間が短くなる。これにより、連通路内の熱媒体に占める、流入路内及び流出路内の熱媒体が凍結して流入路及び流出路が共に塞がれた閉塞状態になる前に凍結する部分の割合（以下、凍結割合という。）が高くなる。 When the heat exchanger having the above configuration is exposed to a condition in which the heat medium is frozen with the liquid heat medium accumulated in the heat medium flow path, the heat medium in the heat medium flow path is gradually frozen. At this time, in the inflow and outflow passages having a large flow path cross-sectional area, the time required for the internal heat medium to completely freeze becomes long, and in the continuous passage having a small flow path cross-sectional area, the internal heat medium is completely frozen. The time required to freeze is shortened. As a result, the proportion of the heat medium in the communication passage that freezes before the heat medium in the inflow passage and the outflow passage freezes and the inflow passage and the outflow passage are both blocked and blocked (hereinafter referred to as , The freezing rate) becomes high.

流入路及び流出路が上記閉塞状態になる前であれば、連通路内の熱媒体が凍結する際の膨張圧は、流入路内又は流出路内に残る未凍結部分を通じて、流入口又は流出口から外部へ逃げることができる。したがって、上記構成によれば、流入路及び流出路が上記閉塞状態になる前における連通路内の熱媒体の凍結割合を高めることによって、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる。 Before the inflow passage and the outflow passage are in the blocked state, the expansion pressure when the heat medium in the communication passage is frozen is applied to the inflow port or the outflow port through the unfrozen portion remaining in the inflow passage or the outflow passage. Can escape from. Therefore, according to the above configuration, by increasing the freezing ratio of the heat medium in the communication passage before the inflow passage and the outflow passage are in the blocked state, the expansion pressure when the heat medium in the communication passage freezes flows. It can escape to the outside from the inlet or outlet.

上記熱交換器において、上記流入路の熱媒体流通方向における断面積及び上記流出路の熱媒体流通方向における断面積の少なくとも一方は、上記連通路の熱媒体流通方向における断面積の５倍以上であることが好ましい。 In the heat exchanger, at least one of the cross-sectional area of the inflow path in the heat medium flow direction and the cross-sectional area of the outflow path in the heat medium flow direction is at least five times the cross-sectional area of the communication passage in the heat medium flow direction. It is preferable to have.

上記構成によれば、流入路及び流出路が上記閉塞状態になる前に、連通路内の熱媒体の全て又は大部分を凍結させることができる。そのため、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる効果がより顕著に得られる。 According to the above configuration, all or most of the heat medium in the communication passage can be frozen before the inflow passage and the outflow passage are in the blocked state. Therefore, the effect that the expansion pressure when the heat medium in the communication passage freezes can be released to the outside from the inlet or outlet can be obtained more remarkably.

上記熱交換器において、上記仕切壁は、上記流入路と上記流出路との間を仕切る中実の壁部であることが好ましい。
上記構成によれば、連通路内の熱媒体が凍結した際の膨張圧によって、連通路の内部応力が過度に上昇して、仕切壁にクラックが生じたとしても、クラックが熱交換器の外部に達するまでの距離が長くなるため、外部への液漏れが生じ難い。 In the heat exchanger, the partition wall is preferably a solid wall portion that partitions between the inflow path and the outflow path.
According to the above configuration, even if the internal stress of the communication passage is excessively increased due to the expansion pressure when the heat medium in the communication passage is frozen and the partition wall is cracked, the crack is outside the heat exchanger. Since the distance to reach is long, it is difficult for liquid to leak to the outside.

上記熱交換器において、上記仕切壁の熱伝導率は、上記区画壁における上記流入路又は上記流出路を挟んで上記仕切壁の反対側に位置する部分の熱伝導率以上であることが好ましい。 In the heat exchanger, the thermal conductivity of the partition wall is preferably equal to or higher than the thermal conductivity of the portion of the partition wall located on the opposite side of the inflow path or the outflow path across the partition wall.

上記構成によれば、熱交換器の外部の温度が仕切壁を通じて連通路内の熱媒体に伝わりやすくなり、流入路及び流出路が上記閉塞状態になる前における連通路内の熱媒体の凍結割合が高くなりやすい。その結果、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる効果がより顕著に得られる。 According to the above configuration, the temperature outside the heat exchanger is easily transmitted to the heat medium in the communication passage through the partition wall, and the freezing ratio of the heat medium in the communication passage before the inflow passage and the outflow passage are in the blocked state. Is likely to be high. As a result, the effect that the expansion pressure when the heat medium in the communication passage freezes can be released to the outside from the inlet or outlet can be obtained more remarkably.

上記熱交換器において、上記区画壁は、炭化ケイ素を主成分として含有し、上記仕切壁の炭化ケイ素の体積含有率は、上記区画壁における上記流入路又は上記流出路を挟んで上記仕切壁の反対側に位置する部分の炭化ケイ素の体積含有率以上であることが好ましい。 In the heat exchanger, the partition wall contains silicon carbide as a main component, and the volume content of silicon carbide in the partition wall is the volume content of the partition wall across the inflow path or the outflow path in the partition wall. It is preferably equal to or greater than the volume content of silicon carbide in the portion located on the opposite side.

上記構成によれば、仕切壁の熱伝導率を容易に調整できる。
上記熱交換器において、上記仕切壁は、上記連通路の壁面を構成する上記仕切壁以外の上記区画壁よりも強度が低いことが好ましい。 According to the above configuration, the thermal conductivity of the partition wall can be easily adjusted.
In the heat exchanger, it is preferable that the partition wall has a lower strength than the partition wall other than the partition wall constituting the wall surface of the communication passage.

上記構成によれば、連通路内の熱媒体が凍結した際の膨張圧によって、連通路の内部応力が過度に上昇した際に、相対的に強度の低い仕切壁に優先的にクラックが生じる。これにより、連通路の内部応力の上昇が緩和されて、連通路を区画する仕切壁以外の区画壁にクラックが生じ難くなる。流入路及び流出路を仕切る中実の仕切壁は、クラックが生じたとしても液漏れが生じ難いため、仕切壁に優先的にクラックを生じさせて、連通路を区画する仕切壁以外の区画壁にクラックを生じ難くすることにより、熱交換器の外部及び連通路に隣接するガス流通路へのクラックを通じた熱媒体の漏れを抑制できる。 According to the above configuration, when the internal stress of the communication passage is excessively increased due to the expansion pressure when the heat medium in the communication passage is frozen, cracks are preferentially generated in the partition wall having a relatively low strength. As a result, the increase in internal stress of the communication passage is alleviated, and cracks are less likely to occur in the partition wall other than the partition wall that divides the communication passage. Since the solid partition wall that separates the inflow path and the outflow path is unlikely to leak liquid even if a crack occurs, the partition wall is preferentially cracked to form a partition wall other than the partition wall that partitions the continuous passage. By making it difficult for cracks to occur, it is possible to suppress leakage of the heat medium through cracks to the outside of the heat exchanger and the gas flow passage adjacent to the communication passage.

本発明の熱交換器によれば、熱媒体流通路内の熱媒体が凍結した際に生じる膨張圧が流入口又は流出口から外部へ逃げやすくなる。 According to the heat exchanger of the present invention, the expansion pressure generated when the heat medium in the heat medium flow path freezes easily escapes to the outside from the inflow port or the outflow port.

熱交換器の斜視図。Perspective view of the heat exchanger. 図１の２−２線断面図。2-2 sectional view of FIG. 図１の３−３線断面図。FIG. 1 is a sectional view taken along line 3-3 of FIG. 図１の４−４線断面図。FIG. 1 is a sectional view taken along line 4-4 of FIG. 図１の５−５線断面図。FIG. 5-5 is a sectional view taken along line 5-5 of FIG. 第１成形体の斜視図。The perspective view of the 1st molded article. 熱媒体流通路形成工程の説明図。The explanatory view of the heat medium flow path formation process. 第２成形体の斜視図。The perspective view of the 2nd molded article. 脱脂工程の説明図。Explanatory drawing of degreasing process. 含浸工程の説明図。Explanatory drawing of impregnation process. 変更例の熱交換器の斜視図。Perspective view of the heat exchanger of the modified example. 図１１のＸ−Ｘ線断面図。FIG. 11 is a sectional view taken along line XX of FIG. 熱交換器の斜視図。Perspective view of the heat exchanger. 図１３のＹ−Ｙ線断面図。FIG. 13 is a sectional view taken along line YY. 図１３のＺ−Ｚ線断面図。FIG. 13 is a cross-sectional view taken along the line ZZ of FIG.

以下、熱交換器の一実施形態を説明する。
図１〜５に示すように、熱交換器１０は、矩形筒状の周壁１１と、周壁１１の内部を複数のガス流通路Ｒ１と複数の熱媒体流通路Ｒ２に区画する区画壁１２とを備えている。 Hereinafter, an embodiment of the heat exchanger will be described.
As shown in FIGS. 1 to 5, the heat exchanger 10 has a rectangular tubular peripheral wall 11 and a partition wall 12 for partitioning the inside of the peripheral wall 11 into a plurality of gas flow passages R1 and a plurality of heat medium flow passages R2. I have.

図２に示すように、矩形筒状の周壁１１は、上下に対向する一対の横側壁１１ａと、左右に対向する一対の縦側壁１１ｂとを有し、周壁１１の軸方向に直交する断面形状が横長の長方形をなすように構成されている。以下では、周壁１１の軸方向を単に軸方向と記載する。 As shown in FIG. 2, the rectangular tubular peripheral wall 11 has a pair of lateral side walls 11a facing vertically and a pair of vertical side walls 11b facing left and right, and has a cross-sectional shape orthogonal to the axial direction of the peripheral wall 11. Is configured to form a horizontally long rectangle. Hereinafter, the axial direction of the peripheral wall 11 is simply referred to as the axial direction.

図２、３に示すように、区画壁１２は、横側壁１１ａに平行な第１区画壁１２ａと、第１区画壁１２ａ同士を接続するとともに、縦側壁１１ｂに平行な第２区画壁１２ｂとを備える。また、図２、３に示すように、区画壁１２は、所定の隣り合う第２区画壁１２ｂ同士の間を部分的に接続するように配置され、縦側壁１１ｂに平行な第３区画壁１２ｃ及び仕切壁１２ｄを備える。 As shown in FIGS. 2 and 3, the partition wall 12 connects the first partition wall 12a parallel to the lateral side wall 11a and the first partition wall 12a to each other, and also connects the second partition wall 12b parallel to the vertical side wall 11b. To be equipped. Further, as shown in FIGS. 2 and 3, the partition wall 12 is arranged so as to partially connect the predetermined adjacent second partition walls 12b to each other, and the third partition wall 12c parallel to the vertical side wall 11b. And a partition wall 12d.

図５に示すように、第３区画壁１２ｃは、縦側壁１１ｂの軸方向の両端部に位置する側縁に沿って上下方向に延びる一対の端壁部１２ｃ１と、縦側壁１１ｂの下縁に沿って軸方向に延びるとともに一対の端壁部１２ｃ１に接続される下壁部１２ｃ２とを備えるＵ字状に形成されている。仕切壁１２ｄは、Ｕ字状の第３区画壁１２ｃの内側に所定の間隔をあけて配置され、縦側壁１１ｂの上縁中央部から下方へ延びる矩形状に形成されている。 As shown in FIG. 5, the third partition wall 12c is formed on a pair of end wall portions 12c1 extending in the vertical direction along the side edges located at both ends in the axial direction of the vertical side wall 11b and the lower edge of the vertical side wall 11b. It is formed in a U shape including a lower wall portion 12c2 extending along the axial direction and being connected to a pair of end wall portions 12c1. The partition walls 12d are arranged inside the U-shaped third partition wall 12c at predetermined intervals, and are formed in a rectangular shape extending downward from the central portion of the upper edge of the vertical side wall 11b.

図２〜４に示すように、周壁１１の内部には、第１区画壁１２ａと第２区画壁１２ｂとによって、軸方向に延びる複数のガス流通セルＣが形成されている。ガス流通セルＣは、ガス流通路Ｒ１を構成する。 As shown in FIGS. 2 to 4, a plurality of gas flow cells C extending in the axial direction are formed inside the peripheral wall 11 by the first partition wall 12a and the second partition wall 12b. The gas distribution cell C constitutes the gas flow passage R1.

図２、５に示すように、周壁１１の内部には、第２区画壁１２ｂ、第３区画壁１２ｃ及び仕切壁１２ｄによって、軸方向に並ぶ一対の流入路１４ａ及び流出路１４ｂと、軸方向に延びるとともに流入路１４ａと流出路１４ｂとを連通する連通路１３とが形成されている。流入路１４ａ、流出路１４ｂ、及び連通路１３は、熱媒体流通路Ｒ２を構成する。したがって、流入路１４ａの周壁１１に開口する端部は、熱媒体流通路Ｒ２の流入口１５ａとなるとともに、流出路１４ｂの周壁１１に開口する端部は、熱媒体流通路Ｒ２の流出口１５ｂとなる。図１に示すように、本実施形態においては、３組の流入路１４ａ及び流出路１４ｂが軸方向に直交する方向に並ぶように形成されている。 As shown in FIGS. 2 and 5, inside the peripheral wall 11, a pair of inflow passages 14a and outflow passages 14b arranged in the axial direction by the second partition wall 12b, the third partition wall 12c, and the partition wall 12d, and the axial direction. A communication passage 13 that extends to the inflow path 14a and communicates with the outflow path 14b is formed. The inflow passage 14a, the outflow passage 14b, and the communication passage 13 form a heat medium flow passage R2. Therefore, the end opening to the peripheral wall 11 of the inflow passage 14a becomes the inflow port 15a of the heat medium flow passage R2, and the end opening to the peripheral wall 11 of the outflow passage 14b is the outflow outlet 15b of the heat medium flow passage R2. It becomes. As shown in FIG. 1, in the present embodiment, three sets of inflow passages 14a and outflow passages 14b are formed so as to be arranged in a direction orthogonal to the axial direction.

図５に示すように、仕切壁１２ｄは、流入路１４ａと流出路１４ｂとの間を仕切る壁部であり、流入路１４ａ及び流出路１４ｂにおける軸方向内側の壁面を構成するとともに、連通路１３における上側の壁面を構成している。第３区画壁１２ｃは、流入路１４ａ及び流出路１４ｂの軸方向外側の壁面を構成するとともに、連通路１３の下側の壁面を構成している。 As shown in FIG. 5, the partition wall 12d is a wall portion that partitions between the inflow passage 14a and the outflow passage 14b, constitutes an axially inner wall surface in the inflow passage 14a and the outflow passage 14b, and is a continuous passage 13 It constitutes the upper wall surface in. The third partition wall 12c constitutes an axially outer wall surface of the inflow passage 14a and the outflow passage 14b, and also constitutes a lower wall surface of the communication passage 13.

図２に示すように、第３区画壁１２ｃ及び仕切壁１２ｄの厚さＴは、第１区画壁１２ａ及び第２区画壁１２ｂよりも厚く構成され、ガス流通セルＣの幅方向（図中左右方向）の寸法と略等しくなるように構成されている。ここで、第３区画壁１２ｃ及び仕切壁１２ｄの厚さＴとは、ガス流通セルＣの幅方向における第３区画壁１２ｃ及び仕切壁１２ｄの寸法を意味するものとする。 As shown in FIG. 2, the thickness T of the third partition wall 12c and the partition wall 12d is configured to be thicker than that of the first partition wall 12a and the second partition wall 12b, and is formed in the width direction of the gas flow cell C (left and right in the figure). It is configured to be approximately equal to the dimension in the direction). Here, the thickness T of the third partition wall 12c and the partition wall 12d means the dimensions of the third partition wall 12c and the partition wall 12d in the width direction of the gas distribution cell C.

第３区画壁１２ｃ及び仕切壁１２ｄの厚さＴは、ガス流通セルＣの幅方向の寸法（流路幅）に対して、１．０〜５．０倍であることが好ましい。なお、第１区画壁１２ａ及び第２区画壁１２ｂの厚さは、例えば、０．１〜０．５ｍｍであり、第３区画壁１２ｃ及び仕切壁１２ｄの厚さＴは、例えば、０．５〜５．０ｍｍである。また、第３区画壁１２ｃ及び仕切壁１２ｄの厚さＴは、ガス流通セルＣの幅方向（図中左右方向）における、流入路１４ａ及び流出路１４ｂの寸法Ｕ（図３参照）と等しくなるように構成される。 The thickness T of the third partition wall 12c and the partition wall 12d is preferably 1.0 to 5.0 times the dimension in the width direction (flow path width) of the gas flow cell C. The thickness of the first partition wall 12a and the second partition wall 12b is, for example, 0.1 to 0.5 mm, and the thickness T of the third partition wall 12c and the partition wall 12d is, for example, 0.5. It is ~ 5.0 mm. Further, the thickness T of the third partition wall 12c and the partition wall 12d is equal to the dimensions U (see FIG. 3) of the inflow path 14a and the outflow path 14b in the width direction of the gas flow cell C (left-right direction in the figure). It is configured as follows.

次に、ガス流通路Ｒ１を構成するガス流通セルＣについて説明する。
図２〜４に示すように、ガス流通セルＣは、両端部が共に開放され、処理対象のガスを軸方向に沿って流通させることができるように構成されている。ガス流通セルＣは、周壁１１の縦側壁１１ｂに平行にガス流通セルＣが８個配列したセル列Ｃａを備える。セル列Ｃａは、周壁１１の横側壁１１ａに沿って４列設けられている。図２、３に示すように、４列のセル列Ｃａと４列のセル列Ｃａとの間に第３区画壁１２ｃ及び仕切壁１２ｄが配置されている。そして、４列のセル列Ｃａの隣であって、第３区画壁１２ｃ及び仕切壁１２ｄの間に流入路１４ａ、流出路１４ｂ及び連通路１３が配置されている。そして、これらの配置が繰り返された配置パターンが形成されている。 Next, the gas distribution cell C constituting the gas flow passage R1 will be described.
As shown in FIGS. 2 to 4, the gas flow cell C is configured so that both ends are open and the gas to be processed can be circulated along the axial direction. The gas distribution cell C includes a cell row Ca in which eight gas distribution cells C are arranged in parallel with the vertical side wall 11b of the peripheral wall 11. Four cell rows Ca are provided along the lateral side wall 11a of the peripheral wall 11. As shown in FIGS. 2 and 3, a third partition wall 12c and a partition wall 12d are arranged between the four rows of cell rows Ca and the four rows of cell rows Ca. Next to the four rows of cell rows Ca, an inflow passage 14a, an outflow passage 14b, and a communication passage 13 are arranged between the third partition wall 12c and the partition wall 12d. Then, an arrangement pattern in which these arrangements are repeated is formed.

ガス流通セルＣを流通させる処理対象のガスとしては、例えば、内燃機関の排気ガスが挙げられる。ガス流通セルＣのセル構造は特に限定されるものではないが、例えば、第１区画壁１２ａ及び第２区画壁１２ｂの壁厚が０．１〜０．５ｍｍであり、セル密度が、周壁１１の軸方向に直交する断面１ｃｍ^２あたり１５〜９３セルであるセル構造とすることができる。 Examples of the gas to be processed in which the gas distribution cell C is distributed include the exhaust gas of an internal combustion engine. The cell structure of the gas flow cell C is not particularly limited, but for example, the wall thickness of the first partition wall 12a and the second partition wall 12b is 0.1 to 0.5 mm, and the cell density is the peripheral wall 11. It is possible to have a cell structure having 15 to 93 cells per ^{1 cm 2} in cross section orthogonal to the axial direction of.

次に、熱媒体流通路Ｒ２について説明する。
図５に示すように、熱媒体流通路Ｒ２は、周壁１１に開口する流入口１５ａを有する流入路１４ａと、周壁１１に開口する流出口１５ｂを有する流出路１４ｂと、流入路１４ａ及び流出路１４ｂの下側の端部に連通される連通路１３とを備えるＵ字状に形成されている。流入路１４ａ及び流出路１４ｂは、軸方向における中央に配置される仕切壁１２ｄを挟んで軸方向に並設されている。また、流入路１４ａ及び流出路１４ｂは、軸方向に直交する方向に平行に延びるように形成されている。 Next, the heat medium flow path R2 will be described.
As shown in FIG. 5, the heat medium flow passage R2 includes an inflow passage 14a having an inflow port 15a opening in the peripheral wall 11, an outflow passage 14b having an outflow outlet 15b opening in the peripheral wall 11, an inflow passage 14a, and an outflow passage. It is formed in a U shape including a communication passage 13 communicating with the lower end of 14b. The inflow path 14a and the outflow path 14b are arranged side by side in the axial direction with the partition wall 12d arranged at the center in the axial direction interposed therebetween. Further, the inflow path 14a and the outflow path 14b are formed so as to extend in parallel in a direction orthogonal to the axial direction.

熱交換効率を高める観点において、流入路１４ａの軸方向の長さと流出路１４ｂの軸方向の長さとの合計は、ガス流通セルＣの軸方向の長さの１／２以上であることが好ましい。また、流入路１４ａ及び流出路１４ｂの上下方向の長さは、流入路１４ａ及び流出路１４ｂの下端が熱交換器１０の中心よりも下側に位置する長さであることが好ましい。 From the viewpoint of increasing the heat exchange efficiency, the total of the axial length of the inflow path 14a and the axial length of the outflow path 14b is preferably 1/2 or more of the axial length of the gas flow cell C. .. Further, the vertical lengths of the inflow path 14a and the outflow path 14b are preferably such that the lower ends of the inflow path 14a and the outflow path 14b are located below the center of the heat exchanger 10.

図２、３に示すように、ガス流通セルＣの幅方向（図中左右方向）において、熱媒体流通路Ｒ２の両側にガス流通セルＣが設けられ、熱媒体流通路Ｒ２は、第２区画壁１２ｂを介してガス流通セルＣに隣接している。 As shown in FIGS. 2 and 3, gas flow cells C are provided on both sides of the heat medium flow passage R2 in the width direction of the gas flow cell C (left-right direction in the figure), and the heat medium flow passage R2 is the second section. It is adjacent to the gas flow cell C via the wall 12b.

図５に示すように、熱媒体流通路Ｒ２は、熱媒体流通方向における断面積として規定される流路断面積が、流入路１４ａ及び流出路１４ｂと連通路１３との間で異なっている。詳述すると、流入路１４ａの流路断面積Ａ１は、連通路１３の流路断面積Ａ３よりも大きく、好ましくは連通路１３の流路断面積Ａ３の５倍以上であり、より好ましくは連通路１３の流路断面積Ａ３の１０倍以上である。 As shown in FIG. 5, in the heat medium flow passage R2, the flow path cross-sectional area defined as the cross-sectional area in the heat medium flow direction is different between the inflow passage 14a and the outflow passage 14b and the communication passage 13. More specifically, the flow path cross-sectional area A1 of the inflow passage 14a is larger than the flow path cross-sectional area A3 of the continuous passage 13, preferably 5 times or more the flow path cross-sectional area A3 of the continuous passage 13, and more preferably continuous. It is 10 times or more the flow path cross-sectional area A3 of the passage 13.

流出路１４ｂの流路断面積Ａ２は、連通路１３の流路断面積Ａ３よりも大きく、好ましくは連通路１３の流路断面積Ａ３の５倍以上であり、より好ましくは連通路１３の流路断面積Ａ３の１０倍以上である。また、流入路１４ａの流路断面積Ａ１と流出路１４ｂの流路断面積Ａ２は同じである。連通路１３の流路断面積Ａ３は、例えば、３ｍｍ^２以上であることが好ましい。 The flow path cross-sectional area A2 of the outflow passage 14b is larger than the flow path cross-sectional area A3 of the communication passage 13, preferably 5 times or more the flow path cross-sectional area A3 of the communication passage 13, and more preferably the flow of the communication passage 13. It is 10 times or more the road cross-sectional area A3. Further, the flow path cross-sectional area A1 of the inflow path 14a and the flow path cross-sectional area A2 of the outflow path 14b are the same. The flow path cross-sectional area A3 of the communication ^{passage 13 is preferably, for example, 3 mm 2 or more.}

なお、流入路１４ａの流路断面積Ａ１は、流入口１５ａである一端側から連通路１３に連通される他端側までの全範囲で一定である。流出路１４ｂの流路断面積Ａ２は、流出口１５ｂである一端側から連通路１３に連通される他端側までの全範囲で一定である。連通路１３の流路断面積Ａ３は、流入路１４ａに連通される一端側から流出路１４ｂに連通される他端側までの全範囲で一定である。 The flow path cross-sectional area A1 of the inflow passage 14a is constant over the entire range from one end side of the inflow port 15a to the other end side communicating with the communication passage 13. The flow path cross-sectional area A2 of the outflow passage 14b is constant over the entire range from one end side of the outflow port 15b to the other end side communicating with the communication passage 13. The flow path cross-sectional area A3 of the communication passage 13 is constant over the entire range from one end side communicating with the inflow passage 14a to the other end side communicating with the outflow passage 14b.

図５に示すように、熱交換器１０に供給された熱媒体は、周壁１１に開口する流入口１５ａから熱交換器１０内に流入し、流入路１４ａを通って連通路１３へと流通する。連通路１３へ流通した熱媒体は、軸方向に沿って流入路１４ａ側から流出路１４ｂ側へと流れる。そして、流出路１４ｂを通って、周壁１１に開口する流出口１５ｂから熱交換器１０外へ流出する。 As shown in FIG. 5, the heat medium supplied to the heat exchanger 10 flows into the heat exchanger 10 from the inflow port 15a opening in the peripheral wall 11, and flows to the communication passage 13 through the inflow passage 14a. .. The heat medium flowing through the communication passage 13 flows from the inflow passage 14a side to the outflow passage 14b side along the axial direction. Then, the heat flows out of the heat exchanger 10 from the outflow port 15b that opens to the peripheral wall 11 through the outflow passage 14b.

熱媒体流通路Ｒ２を流通する熱媒体としては、水を用いることができる。
上記構成の熱交換器１０は、ガス流通セルＣを流れるガスと、熱媒体流通路Ｒ２を流れる熱媒体との間で、区画壁１２を介して熱交換を行うことができる。 Water can be used as the heat medium flowing through the heat medium flow passage R2.
The heat exchanger 10 having the above configuration can exchange heat between the gas flowing through the gas flow cell C and the heat medium flowing through the heat medium flow passage R2 via the partition wall 12.

また、熱交換器１０の周壁１１及び区画壁１２は、セラミック材料により構成されている。上記セラミック材料は、特に限定されるものではなく、公知のセラミック製の熱交換器に用いられる材料を用いることができる。上記セラミック材料としては、例えば、炭化ケイ素、炭化タンタル、炭化タングステン等の炭化物、窒化ケイ素、窒化ホウ素等の窒化物が挙げられる。これらの中でも、炭化ケイ素を主成分として含む材料は、他のセラミック材料に比べて熱伝導率が高く、熱交換効率を高くすることができるため好ましい。ここで、主成分とは、５０質量％以上を意味するものとする。炭化ケイ素を主成分として含む材料としては、例えば、炭化ケイ素の粒子と金属ケイ素を含む材料が挙げられる。なお、周壁１１及び区画壁１２は、同じセラミック材料により構成されており、周壁１１及び区画壁１２の各部位の熱伝導率は全て同じである。 Further, the peripheral wall 11 and the partition wall 12 of the heat exchanger 10 are made of a ceramic material. The ceramic material is not particularly limited, and a material used in a known ceramic heat exchanger can be used. Examples of the ceramic material include carbides such as silicon carbide, tantalum carbide and tungsten carbide, and nitrides such as silicon nitride and boron nitride. Among these, a material containing silicon carbide as a main component is preferable because it has a higher thermal conductivity than other ceramic materials and can increase the heat exchange efficiency. Here, the principal component is assumed to mean 50% by mass or more. Examples of the material containing silicon carbide as a main component include materials containing silicon carbide particles and metallic silicon. The peripheral wall 11 and the partition wall 12 are made of the same ceramic material, and the thermal conductivity of each part of the peripheral wall 11 and the partition wall 12 is the same.

図６〜１０に基づいて、熱交換器１０の一製造方法について説明する。
熱交換器１０は、以下に記載する成形工程、熱媒体流通路形成工程、脱脂工程、含浸工程を順に経ることにより製造される。 A method for manufacturing the heat exchanger 10 will be described with reference to FIGS. 6 to 10.
The heat exchanger 10 is manufactured by going through the molding step, the heat medium flow path forming step, the degreasing step, and the impregnation step described below in this order.

（成形工程）
熱交換器の成形に用いる原料として、炭化ケイ素粒子と、有機バインダーと、分散媒とを含有する粘土状の混合物を調製する。 (Molding process)
A clay-like mixture containing silicon carbide particles, an organic binder, and a dispersion medium is prepared as a raw material used for molding the heat exchanger.

有機バインダーとしては、例えば、ポリビニルアルコール、メチルセルロース、エチルセルロース、カルボキシメチルセルロースが挙げられる。これらの有機バインダーの中でも、メチルセルロース、カルボキシメチルセルロースが特に好ましい。また、上記の有機バインダーのうちの一種のみを用いてもよいし、二種以上を併用してもよい。 Examples of the organic binder include polyvinyl alcohol, methyl cellulose, ethyl cellulose, and carboxymethyl cellulose. Among these organic binders, methyl cellulose and carboxymethyl cellulose are particularly preferable. Further, only one of the above organic binders may be used, or two or more of them may be used in combination.

分散媒としては、例えば、水、有機溶剤が挙げられる。有機溶剤としては、例えば、エタノールが挙げられる。また、上記の分散媒のうちの一種のみを用いてもよいし、二種以上を併用してもよい。 Examples of the dispersion medium include water and an organic solvent. Examples of the organic solvent include ethanol. Further, only one of the above dispersion media may be used, or two or more of them may be used in combination.

また、混合物中にその他の成分を更に含有させてもよい。その他の成分としては、例えば、炭化ケイ素以外の材質からなるセラミック粒子、可塑剤、潤滑剤が挙げられる。炭化ケイ素以外の材質からなるセラミック粒子としては、炭化タンタル、炭化タングステン等の炭化物、窒化アルミニウム、窒化ケイ素、窒化ホウ素等の窒化物からなるセラミック粒子が挙げられる。可塑剤としては、例えば、ポリオキシエチレンアルキルエーテル、ポリオキシプロピレンアルキルエーテル等のポリオキシアルキレン系化合物が挙げられる。潤滑剤としては、例えば、グリセリンが挙げられる。 In addition, other components may be further contained in the mixture. Examples of other components include ceramic particles made of a material other than silicon carbide, a plasticizer, and a lubricant. Examples of the ceramic particles made of a material other than silicon carbide include carbides such as tantalum carbide and tungsten carbide, and ceramic particles made of nitrides such as aluminum nitride, silicon nitride and boron nitride. Examples of the plasticizer include polyoxyalkylene compounds such as polyoxyethylene alkyl ether and polyoxypropylene alkyl ether. Examples of the lubricant include glycerin.

図６に示すように、この粘土状の混合物を用いて、ガス流通セルＣが縦方向に８個配列したセル列を備え、このセル列が横方向に４列設けられた矩形筒状の成形体（第１成形体２０）を成形する。必要に応じて、得られた第１成形体２０に対して乾燥処理を行う。乾燥処理の具体的方法としては、例えば、マイクロ波乾燥機、熱風乾燥機、誘電乾燥機、減圧乾燥機、真空乾燥機、凍結乾燥機等を用いた乾燥処理が挙げられる。 As shown in FIG. 6, this clay-like mixture is used to form a rectangular cylinder in which eight gas flow cells C are arranged in the vertical direction and four rows of the cell rows are provided in the horizontal direction. The body (first molded body 20) is molded. If necessary, the obtained first molded product 20 is subjected to a drying treatment. Specific methods of the drying treatment include, for example, a drying treatment using a microwave dryer, a hot air dryer, a dielectric dryer, a vacuum dryer, a vacuum dryer, a freeze dryer and the like.

（熱媒体流通路形成工程）
熱媒体流通路形成工程は、成形工程で得られた複数の成形体の間に層間材を用いて熱媒体流通路を形成する工程である。 (Heat medium flow path forming process)
The heat medium flow path forming step is a step of forming a heat medium flow path between a plurality of molded bodies obtained in the molding step by using an interlayer material.

図７に示すように、第１成形体２０の側面におけるガス流通セルＣの延びる方向の両端部、及び第１成形体２０の側面における下端部に、層間材２１、２２として、第１成形体２０の原料と同じ粘土状の混合物を塗布する。層間材２１は、後の工程を経て第３区画壁１２ｃとなる部分であり、開放部が上方を向いたＵ字状に塗布される。層間材２２は、後の工程を経て仕切壁１２ｄとなる部分であり、第１成形体２０の側面の中央上端部から下方に延びる矩形状に塗布される。 As shown in FIG. 7, the first molded body is formed as interlayer materials 21 and 22 at both ends in the extending direction of the gas flow cell C on the side surface of the first molded body 20 and at the lower end portion on the side surface of the first molded body 20. The same clay-like mixture as the 20 raw materials is applied. The interlayer material 21 is a portion that becomes a third partition wall 12c through a later step, and is applied in a U shape with the open portion facing upward. The interlayer material 22 is a portion that becomes a partition wall 12d through a later step, and is applied in a rectangular shape extending downward from the central upper end portion of the side surface of the first molded body 20.

層間材２１、２２を塗布した第１成形体２０には、必要に応じて乾燥処理が行われる。層間材２１、２２の厚さは、特に限定されないが、ガス流通セルＣの流路幅に対して、１．０〜５．０倍であることが好ましい。 The first molded body 20 coated with the interlayer materials 21 and 22 is subjected to a drying treatment as necessary. The thickness of the interlayer materials 21 and 22 is not particularly limited, but is preferably 1.0 to 5.0 times the flow path width of the gas flow cell C.

図８に示すように、層間材２１、２２を塗布した第１成形体２０を重ね合わせることにより、４個の第１成形体２０の間に、層間材２１、２２が配置された成形体（第２成形体２３）を作製する。ここで、第１成形体２０の側面に層間材２１、２２を塗布する方法に代えて、予め、層間材２１、２２をコ字状等の形状に成形した後、複数の第１成形体２０間に配置してもよい。 As shown in FIG. 8, by superimposing the first molded bodies 20 coated with the interlayer materials 21 and 22, the molded bodies 21 and 22 are arranged between the four first molded bodies 20 ( The second molded body 23) is produced. Here, instead of the method of applying the interlayer materials 21 and 22 to the side surface of the first molded body 20, the interlayer materials 21 and 22 are previously molded into a U-shaped shape, and then a plurality of first molded bodies 20 are formed. It may be placed in between.

（脱脂工程及び含浸工程）
脱脂工程は、第２成形体２３を加熱することによって、第２成形体２３に含まれる有機分を焼失させる工程である。図９に示すように、脱脂工程を経ることにより、炭化ケイ素粒子同士が接触した状態で配置された骨格部分を有する多孔質の脱脂体３０が得られる。 (Degreasing process and impregnation process)
The degreasing step is a step of burning off the organic matter contained in the second molded body 23 by heating the second molded body 23. As shown in FIG. 9, by going through the degreasing step, a porous degreasing body 30 having a skeleton portion arranged in a state where the silicon carbide particles are in contact with each other can be obtained.

含浸工程は、脱脂体３０の各壁の内部に金属ケイ素を含浸させる工程である。含浸工程においては、脱脂体３０に対して金属ケイ素の塊を接触させた状態として、金属ケイ素の融点以上（例えば、１４５０℃以上）に加熱する。これにより、図１０に示すように、溶融した金属ケイ素が毛細管現象によって、脱脂体の骨格部分を構成する粒子間の隙間へ入り込み、同隙間に金属ケイ素が含浸される。 The impregnation step is a step of impregnating the inside of each wall of the degreasing body 30 with metallic silicon. In the impregnation step, the degreased body 30 is brought into contact with the lump of metallic silicon and heated to a temperature equal to or higher than the melting point of the metallic silicon (for example, 1450 ° C. or higher). As a result, as shown in FIG. 10, the molten metallic silicon enters the gaps between the particles constituting the skeleton portion of the degreased body by the capillary phenomenon, and the metallic silicon is impregnated in the gaps.

含浸工程の加熱処理は、脱脂工程の加熱処理から連続して行ってもよい。例えば、加工成形体に対して金属ケイ素の塊を接触させた状態として、金属ケイ素の融点未満の温度で加熱することにより有機分を除去して脱脂体とした後、加熱温度を金属ケイ素の融点以上に上昇させ、溶融した金属ケイ素を脱脂体に含浸させる。上記の含浸工程を経ることにより、筒状の周壁１１と、周壁１１の内部に複数のガス流通セルＣ及び複数の熱媒体流通路Ｒ２を区画する区画壁１２とを備える熱交換器１０が得られる。 The heat treatment of the impregnation step may be performed continuously from the heat treatment of the degreasing step. For example, in a state where a lump of metallic silicon is in contact with a processed molded body, the organic component is removed by heating at a temperature lower than the melting point of metallic silicon to form a degreased body, and then the heating temperature is set to the melting point of metallic silicon. It is raised above and the degreased body is impregnated with the molten metallic silicon. Through the above impregnation step, a heat exchanger 10 including a tubular peripheral wall 11 and a partition wall 12 for partitioning a plurality of gas flow cells C and a plurality of heat medium flow passages R2 inside the peripheral wall 11 is obtained. Be done.

次に、本実施形態の作用及び効果について記載する。
（１）熱交換器は、ガス流通路と、熱媒体流通路と、ガス流通路及び熱媒体流通路を区画する区画壁とを備えている。熱媒体流通路は、流入口を有する流入路と、流出口を有する流出路と、流入路と流出路とを連通する連通路とを備えるＵ字状に形成されている。区画壁は、流入路と流出路との間を仕切るとともに連通路の壁部を構成する仕切壁を備え、流入路の流路断面積及び流出路の流路断面積は、連通路の流路断面積よりも大きい。 Next, the operation and effect of this embodiment will be described.
(1) The heat exchanger includes a gas flow passage, a heat medium flow passage, and a partition wall for partitioning the gas flow passage and the heat medium flow passage. The heat medium flow path is formed in a U shape including an inflow path having an inflow port, an outflow path having an outflow port, and a communication path communicating the inflow path and the outflow path. The partition wall is provided with a partition wall that separates the inflow passage and the outflow passage and constitutes the wall portion of the communication passage, and the flow path cross-sectional area of the inflow passage and the flow path cross-sectional area of the outflow passage are the flow paths of the communication passage. Larger than the cross-sectional area.

上記構成の熱交換器を、熱媒体流通路内に液状の熱媒体が溜まった状態として熱媒体が凍結する条件に曝すと、熱媒体流通路内の熱媒体が徐々に凍結していく。このとき、流路断面積が大きい流入路及び流出路では、内部の熱媒体が完全に凍結するまでに要する時間が長くなり、流路断面積が小さい連通路では、内部の熱媒体が完全に凍結するまでに要する時間が短くなる。これにより、連通路内の熱媒体に占める、流入路内及び流出路内の熱媒体が凍結して流入路及び流出路が共に塞がれた閉塞状態になる前に凍結する部分の割合（以下、凍結割合という。）が高くなる。 When the heat exchanger having the above configuration is exposed to a condition in which the heat medium is frozen with the liquid heat medium accumulated in the heat medium flow path, the heat medium in the heat medium flow path is gradually frozen. At this time, in the inflow passage and the outflow passage having a large flow path cross-sectional area, the time required for the internal heat medium to completely freeze becomes long, and in the continuous passage having a small flow path cross-sectional area, the internal heat medium is completely frozen. The time required to freeze is shortened. As a result, the proportion of the heat medium in the communication passage that freezes before the heat medium in the inflow passage and the outflow passage freezes and the inflow passage and the outflow passage are both blocked and blocked (hereinafter referred to as , The freezing rate) becomes high.

流入路及び流出路が上記閉塞状態になる前であれば、連通路内の熱媒体が凍結する際の膨張圧は、流入路内又は流出路内に残る未凍結部分を通じて、流入口又は流出口から外部へ逃げることができる。したがって、上記構成によれば、流入路及び流出路が上記閉塞状態になる前における連通路内の熱媒体の凍結割合を高めることによって、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる。 Before the inflow passage and the outflow passage are in the blocked state, the expansion pressure when the heat medium in the communication passage is frozen is applied to the inflow port or the outflow port through the unfrozen portion remaining in the inflow passage or the outflow passage. Can escape from. Therefore, according to the above configuration, by increasing the freezing ratio of the heat medium in the communication passage before the inflow passage and the outflow passage are in the blocked state, the expansion pressure when the heat medium in the communication passage freezes flows. It can escape to the outside from the inlet or outlet.

（２）流入路の断面積及び流出路の断面積は、連通路の断面積の５倍以上である。
上記構成によれば、流入路及び流出路が上記閉塞状態になる前に、連通路内の熱媒体の全て又は大部分を凍結させることができる。そのため、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる効果が顕著に得られる。 (2) The cross-sectional area of the inflow passage and the cross-sectional area of the outflow passage are five times or more the cross-sectional area of the continuous passage.
According to the above configuration, all or most of the heat medium in the communication passage can be frozen before the inflow passage and the outflow passage are in the blocked state. Therefore, the effect that the expansion pressure when the heat medium in the communication passage freezes can be released to the outside from the inlet or outlet can be remarkably obtained.

（３）仕切壁は、流入路と流出路との間を仕切る中実の壁部である。
上記構成によれば、連通路内の熱媒体が凍結した際の膨張圧によって、連通路の内部応力が過度に上昇して、仕切壁にクラックが生じたとしても、クラックが熱交換器の外部に達するまでの距離が長くなるため、外部への液漏れが生じ難い。また、仕切壁に生じたクラックが達した先が、流入路又は流出路であれば、実質的に熱媒体流路の外に熱媒体が漏れることはない。 (3) The partition wall is a solid wall portion that separates the inflow path and the outflow path.
According to the above configuration, even if the internal stress of the communication passage is excessively increased due to the expansion pressure when the heat medium in the communication passage is frozen and the partition wall is cracked, the crack is outside the heat exchanger. Since the distance to reach is long, it is difficult for liquid to leak to the outside. Further, if the destination where the crack generated in the partition wall reaches the inflow path or the outflow path, the heat medium does not substantially leak out of the heat medium flow path.

（４）仕切壁は、流入路と流出路との間を仕切る中実の壁部であり、仕切壁の熱伝導率は、区画壁における流入路又は流出路を挟んで仕切壁の反対側に位置する部分である第３区画壁の端壁部の熱伝導率と同じである。 (4) The partition wall is a solid wall portion that separates the inflow path and the outflow path, and the thermal conductivity of the partition wall is on the opposite side of the partition wall across the inflow path or the outflow path in the partition wall. It is the same as the thermal conductivity of the end wall portion of the third partition wall, which is the located portion.

上記構成によれば、熱交換器の外部の温度が仕切壁を通じて連通路内の熱媒体に伝わりやすくなり、流入路及び流出路が上記閉塞状態になる前における連通路内の熱媒体の凍結割合が高くなりやすい。その結果、連通路内の熱媒体が凍結する際の膨張圧を流入口又は流出口から外部へ逃がすことができる効果が顕著に得られる。 According to the above configuration, the temperature outside the heat exchanger is easily transmitted to the heat medium in the communication passage through the partition wall, and the freezing ratio of the heat medium in the communication passage before the inflow passage and the outflow passage are in the blocked state. Is likely to be high. As a result, the effect that the expansion pressure when the heat medium in the communication passage freezes can be released to the outside from the inlet or outlet can be remarkably obtained.

（５）熱交換器は、炭化ケイ素を主成分として含有する。仕切壁の炭化ケイ素の体積含有率は、第３区画壁の端壁部の炭化ケイ素の体積含有率と同じである。
上記構成によれば、仕切壁の熱伝導率を容易に調整できる。 (5) The heat exchanger contains silicon carbide as a main component. The volume content of silicon carbide in the partition wall is the same as the volume content of silicon carbide in the end wall portion of the third partition wall.
According to the above configuration, the thermal conductivity of the partition wall can be easily adjusted.

本実施形態は、次のように変更して実施することも可能である。また、上記実施形態の構成や以下の変更例に示す構成を適宜組み合わせて実施することも可能である。
・流入路の流路断面積と流出路の流路断面積とを異ならせてもよい。この場合、流入路の流路断面積及び流出路の流路断面積のいずれか一方のみが連通路の流路断面積よりも大きい構成としてもよい。 This embodiment can also be modified and implemented as follows. It is also possible to appropriately combine the configurations of the above-described embodiment and the configurations shown in the following modified examples.
-The cross-sectional area of the flow path of the inflow path and the cross-sectional area of the flow path of the outflow path may be different. In this case, only one of the flow path cross-sectional area of the inflow path and the flow path cross-sectional area of the outflow path may be larger than the flow path cross-sectional area of the continuous passage.

・流入路及び流出路は、流路断面積が一定でない形状であってもよい。この場合、流入路及び流出路のそれぞれの流路断面積の平均値を流路断面積とする。
・連通路は、流路断面積が一定でない形状であってもよい。この場合、連通路の流路断面積の平均値を流路断面積とする。 -The inflow path and the outflow path may have a shape in which the cross-sectional area of the flow path is not constant. In this case, the average value of the channel cross-sectional areas of the inflow path and the outflow path is taken as the channel cross-sectional area.
-The continuous passage may have a shape in which the cross-sectional area of the flow path is not constant. In this case, the average value of the flow path cross-sectional area of the continuous passage is taken as the flow path cross-sectional area.

・仕切壁の熱伝導率を、区画壁における流入路又は流出路を挟んで仕切壁の反対側に位置する部分、即ち第３区画壁の端壁部の一方又は両方の熱伝導率よりも高くしてもよい。この場合、上記（４）の効果が更に顕著に得られる。仕切壁の熱伝導率を調整する方法は特に限定されるものではなく、公知の調整方法を採用できる。 -The thermal conductivity of the partition wall is higher than that of the portion of the partition wall located on the opposite side of the partition wall across the inflow path or outflow path, that is, the thermal conductivity of one or both of the end wall portions of the third partition wall. You may. In this case, the effect of (4) above can be obtained more remarkably. The method for adjusting the thermal conductivity of the partition wall is not particularly limited, and a known adjustment method can be adopted.

例えば、炭化ケイ素を主成分として含有する区画壁を採用する場合、仕切壁における炭化ケイ素の体積含有率を第３区画壁の端壁部における炭化ケイ素の体積含有率よりも高くすることによって、仕切壁の相対的な熱伝導率を容易に高めることができる。仕切壁における炭化ケイ素の体積含有率は、例えば、仕切壁の炭化ケイ素の組成比が相対的に高くなるように、又は仕切壁の気孔率が相対的に低くなるように、熱媒体流通路形成工程において、層間材として用いる粘土状の混合物の組成を適宜、変更することにより、調整できる。例えば、仕切壁の炭化ケイ素の組成比が相対的に高くなるように、炭化ケイ素粒子の配合比率を変化させた混合物とする。また、仕切壁の気孔率が低くなるように、金属ケイ素に対する濡れ性を調整する添加剤を含有させた混合物とする。 For example, when a partition wall containing silicon carbide as a main component is adopted, the volume content of silicon carbide in the partition wall is made higher than the volume content of silicon carbide in the end wall portion of the third partition wall. The relative thermal conductivity of the wall can be easily increased. The volume content of silicon carbide in the partition wall is such that, for example, the composition ratio of silicon carbide in the partition wall is relatively high, or the porosity of the partition wall is relatively low. In the step, it can be adjusted by appropriately changing the composition of the clay-like mixture used as the interlayer material. For example, the mixture is prepared by changing the mixing ratio of silicon carbide particles so that the composition ratio of silicon carbide on the partition wall is relatively high. In addition, the mixture contains an additive that adjusts the wettability to metallic silicon so that the porosity of the partition wall is low.

・上記実施形態では、区画壁は、同じセラミック材料により構成されており、区画壁の強度は全て同じであったが、区画壁の部位毎に強度を異ならせてもよい。例えば、仕切壁の強度を、連通路の壁面を構成する仕切壁以外の区画壁、即ち第３区画壁の下壁部、及び第２区画壁の強度よりも低くする。 -In the above embodiment, the partition wall is made of the same ceramic material, and the strength of the partition wall is the same, but the strength may be different for each part of the partition wall. For example, the strength of the partition wall is made lower than the strength of the partition wall other than the partition wall constituting the wall surface of the continuous passage, that is, the lower wall portion of the third partition wall and the second partition wall.

この場合、連通路内の熱媒体が凍結した際の膨張圧によって、連通路の内部応力が過度に上昇した際に、相対的に強度が低い仕切壁に優先的にクラックが生じる。これにより、連通路の内部応力の上昇が緩和されて、連通路を区画する仕切壁以外の区画壁にクラックが生じ難くなる。上記（３）において述べた通り、流入路及び流出路を仕切る中実の仕切壁は、クラックが生じたとしても液漏れが生じ難い。そのため、仕切壁に優先的にクラックを生じさせて、連通路を区画する仕切壁以外の区画壁にクラックを生じ難くすることにより、熱交換器の外部及び連通路に隣接するガス流通路へのクラックを通じた熱媒体の漏れを抑制できる。 In this case, when the internal stress of the communication passage is excessively increased due to the expansion pressure when the heat medium in the communication passage is frozen, cracks are preferentially generated in the partition wall having a relatively low strength. As a result, the increase in internal stress of the communication passage is alleviated, and cracks are less likely to occur in the partition wall other than the partition wall that divides the communication passage. As described in (3) above, the solid partition wall that separates the inflow path and the outflow path is unlikely to leak even if a crack occurs. Therefore, by preferentially causing cracks in the partition wall and making it difficult for cracks to occur in the partition walls other than the partition wall that partitions the communication passage, the outside of the heat exchanger and the gas flow passage adjacent to the communication passage can be reached. Leakage of heat medium through cracks can be suppressed.

また、仕切壁の強度を、流入路又は流出路の壁面を構成する仕切壁以外の区画壁、即ち第３区画壁の端壁部、及び第２区画壁の強度よりも低くしてもよい。この場合にも、同様のメカニズムにより、熱交換器の外部、及び流入路又は流出路に隣接するガス流通路へのクラックを通じた熱媒体の漏れを抑制できる。 Further, the strength of the partition wall may be lower than the strength of the partition wall other than the partition wall constituting the wall surface of the inflow path or the outflow path, that is, the end wall portion of the third partition wall and the second partition wall. In this case as well, the same mechanism can suppress leakage of the heat medium through cracks to the outside of the heat exchanger and to the gas flow path adjacent to the inflow path or the outflow path.

仕切壁の強度を調整する方法は特に限定されるものではなく、公知の調整方法を採用できる。例えば、炭化ケイ素を主成分として含有する区画壁を採用する場合、仕切壁における炭化ケイ素の体積含有率を下壁部及び縦側壁における炭化ケイ素の体積含有率よりも低くすることによって、仕切壁の相対的な強度を容易に低下させることができる。仕切壁における炭化ケイ素の体積含有率は、例えば、仕切壁の炭化ケイ素の組成比が相対的に低くなるように、又は仕切壁の気孔率が相対的に高くなるように、熱媒体流通路形成工程において、層間材として用いる粘土状の混合物の組成を適宜、変更することにより、調整できる。 The method for adjusting the strength of the partition wall is not particularly limited, and a known adjustment method can be adopted. For example, when a partition wall containing silicon carbide as a main component is adopted, the volume content of silicon carbide in the partition wall is made lower than the volume content of silicon carbide in the lower wall portion and the vertical side wall, thereby forming the partition wall. The relative strength can be easily reduced. The volume content of silicon carbide in the partition wall is such that, for example, the composition ratio of silicon carbide in the partition wall is relatively low, or the porosity of the partition wall is relatively high. In the step, it can be adjusted by appropriately changing the composition of the clay-like mixture used as the interlayer material.

・本実施形態では、熱交換器は、幅方向（図２の左右方向）の寸法が、上下方向の寸法よりも大きく構成されていたが、この態様に限定されない。上下方向の寸法の方が、幅方向の寸法よりも大きく構成されていてもよいし、上下方向と幅方向が同じ寸法で構成されていてもよい。 -In the present embodiment, the heat exchanger has a width direction (horizontal direction in FIG. 2) larger than the vertical dimension, but is not limited to this embodiment. The dimensions in the vertical direction may be larger than the dimensions in the width direction, or the dimensions in the vertical direction and the width direction may be the same.

・本実施形態では、ガス流通セルは、周壁の縦側壁に平行にガス流通セルが８個配列し、このセル列が、周壁の横側壁に沿って４列設けられた配置パターンが、熱媒体流通路を介して繰り返されていたが、この態様に限定されない。ガス流通セルの配置パターンは、適宜選択することができる。 -In the present embodiment, in the gas flow cell, eight gas flow cells are arranged parallel to the vertical side wall of the peripheral wall, and the arrangement pattern in which four rows of the cell rows are provided along the horizontal side wall of the peripheral wall is a heat medium. It was repeated through the flow path, but is not limited to this aspect. The arrangement pattern of the gas distribution cell can be appropriately selected.

例えば、図１１、１２に示すように、第３区画壁１２ｃの下壁部１２ｃ２の側方に位置するガス流通セルＣを省略して、熱交換器１０の下側に、下壁部１２ｃ２に相当する厚さの中実の壁が設けられる構成としてもよい。この場合には、熱交換器１０の強度が向上する。 For example, as shown in FIGS. 11 and 12, the gas flow cell C located on the side of the lower wall portion 12c2 of the third partition wall 12c is omitted, and the lower wall portion 12c2 is on the lower side of the heat exchanger 10. A solid wall having a corresponding thickness may be provided. In this case, the strength of the heat exchanger 10 is improved.

・周壁は、矩形筒状に限定されない。円筒状や、断面が楕円形の筒状に構成されていてもよい。また、ガス流通セル及び熱媒体流通路の断面形状は断面矩形状に限定されない。矩形状以外の多角形状であってもよいし、円形や楕円形であってもよい。多角形状の角部が面取りされた形状であってもよい。熱媒体流通路の流入路と流出路とで形状が異なっていてもよい。 -The peripheral wall is not limited to a rectangular cylinder. It may be formed in a cylindrical shape or a tubular shape having an elliptical cross section. Further, the cross-sectional shape of the gas flow cell and the heat medium flow path is not limited to the rectangular cross section. It may be a polygonal shape other than a rectangular shape, or may be a circular shape or an elliptical shape. The corners of the polygonal shape may be chamfered. The shape of the inflow path and the outflow path of the heat medium flow path may be different.

以下、上記実施形態をさらに具体化した実施例について説明する。
流入路、流出路、及び連通路の流路断面積を異ならせた実施例１〜４及び比較例１の熱交換器を作製し、充填した熱媒体を凍結させた際の挙動を観察した。 Hereinafter, an example in which the above embodiment is further embodied will be described.
The heat exchangers of Examples 1 to 4 and Comparative Example 1 having different flow path cross-sectional areas of the inflow path, the outflow path, and the communication passage were prepared, and the behavior when the filled heat medium was frozen was observed.

ガス流通セルが縦方向に２７個配列したセル列を備え、このセル列が横方向に４列設けられた矩形筒状の第１成形体を成形した。第１成形体の各壁の壁厚は、０．１５ｍｍとし、セルサイズは、縦０．９８ｍｍ×横０．９８ｍｍ×長さ８０ｍｍとした。第１成形体の材料として、含浸工程後、炭化ケイ素の体積含有率が６０％となる壁が形成される組成の材料を用いた。 A first molded body having a rectangular cylinder in which 27 gas flow cells were arranged in the vertical direction and four rows of the cell rows were provided in the horizontal direction was formed. The wall thickness of each wall of the first molded product was 0.15 mm, and the cell size was 0.98 mm in length × 0.98 mm in width × 80 mm in length. As the material of the first molded product, a material having a composition in which a wall having a volume content of silicon carbide of 60% was formed after the impregnation step was used.

第１成形体の側面に対して、表１に示す寸法の流入路、流出路、及び連通路を形成するように、厚さ３ｍｍの層間材を塗布した。なお、表１に記載する流入路及び流出路の各幅は、軸方向の長さであり、連通路の幅は、上下方向（縦方向）の長さである。層間材の材料として、含浸工程後、炭化ケイ素の体積含有率が表１に示す数値となる壁が形成される組成の材料を用いた。層間材を挟んで８個の第１成形体を重ね合わせた第２成形体を作製し、脱脂工程及び含浸工程を実施することにより実施例１〜４及び比較例１の熱交換器を得た。 An interlayer material having a thickness of 3 mm was applied to the side surface of the first molded body so as to form an inflow passage, an outflow passage, and a communication passage having the dimensions shown in Table 1. The widths of the inflow passage and the outflow passage shown in Table 1 are the lengths in the axial direction, and the widths of the communication passages are the lengths in the vertical direction (vertical direction). As the material of the interlayer material, a material having a composition in which a wall having a volume content of silicon carbide having a numerical value shown in Table 1 was formed after the impregnation step was used. A second molded body was prepared by superimposing eight first molded bodies with an interlayer material sandwiched between them, and the degreasing step and the impregnation step were carried out to obtain heat exchangers of Examples 1 to 4 and Comparative Example 1. ..

得られた実施例１〜４及び比較例１の熱交換器の熱媒体流路である流入路、流出路、及び連通路に熱媒体としての水を充填した状態とし、−１９℃の恒温槽に２時間放置した後に目視でクラックの有無を確認した。その結果を表１に示す。 The inflow passage, the outflow passage, and the communication passage, which are the heat medium passages of the heat exchangers of Examples 1 to 4 and Comparative Example 1, were filled with water as a heat medium, and a constant temperature bath at -19 ° C. After leaving it for 2 hours, the presence or absence of cracks was visually confirmed. The results are shown in Table 1.

表１に示すように、流入路の流路断面積及び流出路の流路断面積が連通路の流路断面積と同じである比較例１の場合、充填した熱媒体を凍結させることによりクラックが発生した。一方、流入路の流路断面積及び流出路の流路断面積が連通路の流路断面積よりも大きい実施例１〜４の場合、充填した熱媒体を凍結させてもクラックは発生しなかった。 As shown in Table 1, in the case of Comparative Example 1 in which the flow path cross-sectional area of the inflow path and the flow path cross-sectional area of the outflow path are the same as the flow path cross-sectional area of the continuous passage, cracks are caused by freezing the filled heat medium. There has occurred. On the other hand, in the cases of Examples 1 to 4 in which the flow path cross-sectional area of the inflow path and the flow path cross-sectional area of the outflow path are larger than the flow path cross-sectional area of the continuous passage, no crack occurs even if the filled heat medium is frozen. It was.

Ａ１…流入路の流路断面積、Ａ２…流出路の流路断面積、Ａ３…連通路の流路断面積、Ｒ１…ガス流通路、Ｒ２…熱媒体流通路、１０…熱交換器、１１…周壁、１２…区画壁、１２ａ…第１区画壁、１２ｂ…第２区画壁、１２ｃ…第３区画壁、１２ｃ１…端壁部、１２ｃ２…下壁部、１２ｄ…仕切壁、１３…連通路、１４ａ…流入路、１４ｂ…流出路、１５ａ…流入口、１５ｂ…流出口、２０…第１成形体、２１、２２…層間材、２３…第２成形体、３０…脱脂体、Ｒ１…ガス流通路、Ｒ２…熱媒体流通路。 A1 ... Flow path cross-sectional area of inflow path, A2 ... Flow path cross-sectional area of outflow path, A3 ... Flow path cross-sectional area of continuous passage, R1 ... Gas flow path, R2 ... Heat medium flow path, 10 ... Heat exchanger, 11 ... peripheral wall, 12 ... partition wall, 12a ... first partition wall, 12b ... second partition wall, 12c ... third partition wall, 12c1 ... end wall, 12c2 ... lower wall, 12d ... partition wall, 13 ... continuous passage , 14a ... Inflow path, 14b ... Outflow path, 15a ... Inflow port, 15b ... Outlet, 20 ... First molded body, 21, 22 ... Interlayer material, 23 ... Second molded body, 30 ... Degreased body, R1 ... Gas Flow passage, R2 ... Heat medium flow passage.

Claims (6)

ガス流通路と、熱媒体流通路と、前記ガス流通路及び前記熱媒体流通路を区画する区画壁とを備え、前記ガス流通路を流通するガスと、前記熱媒体流通路を流通する液状の熱媒体との間で熱交換が行われるセラミック製の熱交換器であって、
前記熱媒体流通路は、流入口を有する流入路と、流出口を有する流出路と、前記流入路と前記流出路とを連通する連通路とを備えるＵ字状に形成され、
前記区画壁は、前記流入路と前記流出路との間を仕切るとともに前記連通路の壁面を構成する仕切壁を備え、
前記流入路の熱媒体流通方向における断面積及び前記流出路の熱媒体流通方向における断面積の少なくとも一方は、前記連通路の熱媒体流通方向における断面積よりも大きいことを特徴とする熱交換器。 A gas flow passage, a heat medium flow passage, a partition wall for partitioning the gas flow passage and the heat medium flow passage, and a liquid flowing through the gas flow passage and the heat medium flow passage. A ceramic heat exchanger that exchanges heat with a heat medium.
The heat medium flow path is formed in a U shape including an inflow path having an inflow port, an outflow path having an outflow port, and a communication path communicating the inflow path and the outflow path.
The partition wall includes a partition wall that partitions the inflow passage and the outflow passage and constitutes a wall surface of the communication passage.
A heat exchanger characterized in that at least one of the cross-sectional area of the inflow path in the heat medium flow direction and the cross-sectional area of the outflow path in the heat medium flow direction is larger than the cross-sectional area of the communication passage in the heat medium flow direction. .. 前記流入路の熱媒体流通方向における断面積及び前記流出路の熱媒体流通方向における断面積の少なくとも一方は、前記連通路の熱媒体流通方向における断面積の５倍以上である請求項１に記載の熱交換器。 The first aspect of claim 1, wherein at least one of the cross-sectional area of the inflow path in the heat medium flow direction and the cross-sectional area of the outflow path in the heat medium flow direction is five times or more the cross-sectional area of the communication passage in the heat medium flow direction. Heat exchanger. 前記仕切壁は、前記流入路と前記流出路との間を仕切る中実の壁部である請求項１又は請求項２に記載の熱交換器。 The heat exchanger according to claim 1 or 2, wherein the partition wall is a solid wall portion that partitions the inflow path and the outflow path. 前記仕切壁の熱伝導率は、前記区画壁における前記流入路又は前記流出路を挟んで前記仕切壁の反対側に位置する部分の熱伝導率以上である請求項３に記載の熱交換器。 The heat exchanger according to claim 3, wherein the thermal conductivity of the partition wall is equal to or higher than the thermal conductivity of a portion of the partition wall located on the opposite side of the inflow path or the outflow path across the partition wall. 前記区画壁は、炭化ケイ素を主成分として含有し、
前記仕切壁の炭化ケイ素の体積含有率は、前記区画壁における前記流入路又は前記流出路を挟んで前記仕切壁の反対側に位置する部分の炭化ケイ素の体積含有率以上である請求項４に記載の熱交換器。 The partition wall contains silicon carbide as a main component and contains
The volume content of silicon carbide in the partition wall is equal to or greater than the volume content of silicon carbide in the partition wall located on the opposite side of the inflow path or the outflow path across the partition wall. The heat exchanger described. 前記仕切壁は、前記連通路の壁面を構成する前記仕切壁以外の前記区画壁よりも強度が低い請求項１〜３のいずれか一項に記載の熱交換器。 The heat exchanger according to any one of claims 1 to 3, wherein the partition wall has a strength lower than that of the partition wall other than the partition wall constituting the wall surface of the communication passage.