JPS60142196A - Lamination type heat exchanger - Google Patents

Abstract

PURPOSE:To form the lamination type heat exchanger high in heat transfer by a method wherein protuberances are provided in a flow path and the tip end of the protuberance is separated from corresponding wall surface to restrict the development of laminar boundary layer and secure thin liquid film on the whole of the wall surface of flow path. CONSTITUTION:A heat exchanger is provided with protuberances 9 and recesses 10 to provide the flow direction thereof with an angle whereby a secondary flow is generated and the development of the laminar boundary layer is precluded. In the two phase flow of gas and liquid, liquid phase 11 is collected by a surface tension at a narrow clearance between wall surfaces corresponding to the protuberance 9 and the corner of the recess 10, liquid film is secured widely on the wall surface upon boiling and dry surface is not generated so much, therefore, a high heat transfer may be obtained as a whole. On the other hand, the thin liquid film is secured on the whole of the wall since the liquid is dispersed upon condensing, heat resistance due to the liquid film is reduced, a high heat transfer may be obtained and heat transfer area may be increased.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、複数の流体間での熱交換に用いる熱交換器に
関するものであり、平板を摺曲させることなく平板上に
機械加工や工、チング等により溝を掘り、積層して形成
される空間を流体の流路とし、臨接する平板を流れる他
流体と熱交換を行なう熱交換器に関するものである。例
えば空調機の水冷式凝縮器やチラー用蒸発器に利用され
る。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat exchanger used for heat exchange between a plurality of fluids. This relates to a heat exchanger that uses a space formed by digging a groove and stacking layers as a fluid flow path to exchange heat with another fluid flowing through an adjacent flat plate. For example, it is used in water-cooled condensers for air conditioners and evaporators for chillers.

従来例の構成とその問題点 図面を参照しながら、従来の積層式熱交換器について説
明する。The structure of a conventional example and its problems A conventional laminated heat exchanger will be explained with reference to the drawings.

第１図は積層式熱交換器の全体の斜視図である。FIG. 1 is a perspective view of the entire stacked heat exchanger.

溝加工した平板１を多数重ね、その両側に端板２を重ね
、溝から流体が漏れないように平板１および端板２を密
着させ、流体の出入管３を取り付けた構造を有している
。第２図は平板１の従来例を示す斜視図である。なお、
これは２流体間の熱交換に用いられる例である。出入管
３より流入した流体はヘッダー４に入り、溝部らに分か
れて流出する。そしてもう一方のヘッダー４で集められ
熱交換器より流出する。６は他流体のヘッダーであり、
平板１を９００ｆつ回転させて積み重ねることにより一
枚ごとに異なる流体が流れる構造になる。It has a structure in which a large number of grooved flat plates 1 are stacked, end plates 2 are stacked on both sides, the flat plates 1 and end plates 2 are brought into close contact to prevent fluid from leaking from the grooves, and a fluid inlet/outlet pipe 3 is attached. . FIG. 2 is a perspective view showing a conventional example of the flat plate 1. In addition,
This is an example used for heat exchange between two fluids. Fluid flowing in through the inlet/outlet pipe 3 enters the header 4, is divided into grooves, and then flows out. Then, it is collected at the other header 4 and flows out from the heat exchanger. 6 is a header for other fluids;
By rotating the flat plates 1 by 900 f and stacking them, a structure is created in which a different fluid flows through each plate.

したがって溝部６が熱交換部となり、上下双方の他流体
と熱交換する形式となる。Therefore, the groove portion 6 becomes a heat exchange portion, which exchanges heat with other fluids both above and below.

第３図は組立て時の流路断面と気液二相流が流れる場合
の流動形態を示している。このような流路では流路の大
部分が境界層の十分発達した流れとなる。したがってあ
１り高い熱伝達率は得らハない。寸だ気液二相流が流れ
る」烏合には、表面張力により第３図に示す流動形態に
なる。っまり液相７が端部に集中し、気相８は中火部に
位置する。FIG. 3 shows the flow path cross section during assembly and the flow form when a gas-liquid two-phase flow flows. In such a flow path, most of the flow path becomes a flow with a well-developed boundary layer. Therefore, it is not possible to obtain a very high heat transfer coefficient. In the case where a gas-liquid two-phase flow flows, the flow pattern shown in FIG. 3 occurs due to surface tension. The liquid phase 7 is concentrated at the end, and the gas phase 8 is located in the middle heat section.

例えば流路内で沸騰させる場合、流路中央部の壁面は乾
いてし寸い伝熱に寄与しなくなる。流路壁面全体の平均
熱伝達率も低下する。特にボイド等が太きい流れでこの
低下は著しい。また高熱負荷時においても同様な傾向が
表われる。一方凝縮させる場合も、流路両端部に厚い液
膜が形成されるだめ熱抵抗が増加し、凝縮熱伝達が極め
て低下する。特に低ボイド率の領域で著しい。For example, when boiling occurs in a flow channel, the wall surface in the center of the flow channel becomes dry and no longer contributes to heat transfer. The average heat transfer coefficient of the entire channel wall also decreases. This decrease is particularly noticeable in flows with large voids. A similar tendency also appears under high heat loads. On the other hand, in the case of condensation, thick liquid films are formed at both ends of the flow path, resulting in increased thermal resistance and extremely reduced condensation heat transfer. This is especially noticeable in areas with low void ratios.

発明の目的 本発明の目的は、境界層の発達を抑制するとともに、気
液二相流体が流れる場合に、流路壁面全体に薄い液膜を
確保し、沸騰時の乾き面の発生および凝縮時の液膜によ
る熱抵抗抑制し、高熱伝達の積層式熱交換器を可能にす
るものである。Purpose of the Invention The purpose of the present invention is to suppress the development of a boundary layer and to ensure a thin liquid film on the entire channel wall surface when a gas-liquid two-phase fluid flows, thereby preventing the occurrence of dry surfaces during boiling and condensation. This technology suppresses thermal resistance due to the liquid film and enables a laminated heat exchanger with high heat transfer.

発明の構成 本発明は、流路内に凸部を設は境界層の発達を抑制する
とともに、凸部先端を対応する壁面から離間させること
により、液相を凸部と対応する壁面間の狭いすきまおよ
び凹部の角部に保持させることにより壁全体にわたり薄
い液膜を確保するものである。Structure of the Invention The present invention suppresses the development of a boundary layer by providing a convex portion in a flow path, and also separates the tip of the convex portion from the corresponding wall surface, thereby directing the liquid phase to the narrow space between the convex portion and the corresponding wall surface. A thin liquid film is maintained over the entire wall by holding it in gaps and corners of recesses.

実施例の説明 図面を参照しながら、本発明の積層式熱交換器について
説明する。DESCRIPTION OF EXEMPLARY EMBODIMENTS A stacked heat exchanger of the present invention will be described with reference to the drawings.

第４図は本発明の一実施例の熱交換器の流路を示すもの
で同−積層板内の１つの流路を拡大したものである。第
６図はそれを組立てた時の第４図のＡ断面と気液二相流
の流動形態を示している。FIG. 4 shows the flow paths of a heat exchanger according to an embodiment of the present invention, and is an enlarged view of one flow path within the laminate. FIG. 6 shows cross-section A in FIG. 4 and the flow form of the gas-liquid two-phase flow when it is assembled.

第４図中９が凸部で１０が四部である。流路の方向に対
して角度をつけることにより二次流れが生じ境界層の発
達を阻害している。第６図中の１１は液相で１２は気相
である。二相流では表面張力により液相は凸部９と対応
する壁面間の狭いすき１および凹部１０の角部に集まる
。しだがって沸騰時には液膜が壁面上に広く確保され、
乾き面があまり生じないことから全体的に高い熱伝達を
得ることができる。In FIG. 4, 9 is a convex portion and 10 is a four part. By setting an angle to the direction of the flow path, a secondary flow is generated and the development of the boundary layer is inhibited. In FIG. 6, 11 is a liquid phase and 12 is a gas phase. In the two-phase flow, the liquid phase gathers in the narrow gap 1 between the convex portion 9 and the corresponding wall surface and at the corner of the concave portion 10 due to surface tension. Therefore, during boiling, a large liquid film is maintained on the wall surface,
High overall heat transfer can be obtained since there are few dry surfaces.

一方凝縮時にも、液が分散することから壁全体にわたり
薄い液膜が確保され、液膜による熱抵抗が減少し高い熱
伝達を得ることができる。−！た伝熱面積が増加するこ
とも伝熱的に有利といえる。On the other hand, during condensation, the liquid disperses, ensuring a thin liquid film over the entire wall, reducing thermal resistance due to the liquid film, and achieving high heat transfer. -! It can also be said that an increase in the heat transfer area is advantageous in terms of heat transfer.

この実施例では凸部９はすべて対応する壁面との間にす
き寸を作るとしたが、耐圧を強化する意味で部分的にす
き寸を作らない構造にしても、伝熱性能が極度に低下す
ることはない。In this embodiment, all the convex parts 9 have gaps between them and the corresponding wall surfaces, but even if the structure is designed so that no gaps are created in some areas in order to strengthen the pressure resistance, the heat transfer performance will be extremely reduced. There's nothing to do.

第６図に本発明の他の実施例を示す、第４図と同様に１
つの流路の拡大平面図である。凸部１３を切断し、捷た
流路方向に対する角度を変化させることにより、よシニ
次流れの効果を犬きくした例である。なお１４は凹部、
１５は側壁である。FIG. 6 shows another embodiment of the present invention.
FIG. 3 is an enlarged plan view of two channels. This is an example in which the effect of a narrow flow is enhanced by cutting the convex portion 13 and changing the angle with respect to the direction of the twisted flow path. Note that 14 is a concave portion,
15 is a side wall.

第７図は本発明の他の実施例の１つの流路の拡大平面図
である。凸部１６の形状をだ円形にしたものでより強い
２次流れの効果を生む。また流体の圧力損失を低減した
い場合には、だ円の縦横比を変化させ流れ方向により細
長くしてもよく、さらに流線形状としても、二相状態に
おける前記液膜の確保は十分効果がある。なお、１７は
凹部、１８は端部である。FIG. 7 is an enlarged plan view of one flow path of another embodiment of the invention. The elliptical shape of the convex portion 16 produces a stronger secondary flow effect. In addition, if you want to reduce the pressure loss of the fluid, you can change the aspect ratio of the ellipse to make it more slender in the flow direction, and even a streamlined shape is sufficiently effective in securing the liquid film in the two-phase state. . Note that 17 is a recess and 18 is an end.

なお、実施例では凸部の断面形状を矩形としているが先
端部に丸みを持たせても同様な効果が期待できる。寸だ
凸部は側壁に接したものばかりでも構成できる。In the embodiment, the cross-sectional shape of the convex portion is rectangular, but the same effect can be expected even if the tip is rounded. The convex portion can also be formed by only being in contact with the side wall.

発明の効果 以上のことから、本発明により境界層の発達を抑制する
とともに、気液二相流において流路壁面全体に薄い液膜
を確保し、沸騰時の乾き面の発生および凝縮時の液膜に
よる熱抵抗抑制し、高熱伝達の積層式熱交換器を得るこ
とができる。From the above effects of the invention, the present invention suppresses the development of a boundary layer, secures a thin liquid film on the entire channel wall surface in a gas-liquid two-phase flow, and prevents the formation of a dry surface during boiling and the liquid during condensation. It is possible to obtain a laminated heat exchanger with high heat transfer by suppressing thermal resistance due to the membrane.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は積層式熱交換器の全体の斜視図、第２図は第１
図の熱交換器を構成する平板の斜視−、第３図は善≠第
１図における＋？１層式熱式熱交換器路断面および気液
二相流の流動形態の説明図、第４図は本発明の一実施例
の積層式熱交換器における流路平面図、第６図は第４図
Ａ−Ａ面流路断面図、第６図および第７図は各本発明の
他の実施例の積層式熱交換器における流路平面図である
。 ９・・・・凸部、１ｏ・・・・・凹部、１１・・・・・
液層、１２・・・・・気相。 代理人の氏名　弁理士　中　尾　敏　男　ほか１老躯１
図 鶏３図 第　６　図 ／３／４ Ｉ３　／４Figure 1 is a perspective view of the entire stacked heat exchanger, Figure 2 is the
A perspective view of the flat plate constituting the heat exchanger shown in the figure -, Figure 3 is good ≠ + in Figure 1? An explanatory diagram of the passage cross-section of a single-layer thermal heat exchanger and the flow form of the gas-liquid two-phase flow, FIG. 4 is a plan view of the flow passage in a stacked heat exchanger according to an embodiment of the present invention, FIG. 4 is a cross-sectional view of the flow path taken along the line A-A, and FIGS. 6 and 7 are flow path plan views in laminated heat exchangers according to other embodiments of the present invention. 9...Convex part, 1o...Concave part, 11...
liquid phase, 12... gas phase. Name of agent: Patent attorney Toshio Nakao and 1 other person
Figure 3 Figure 6 Figure/3/4 I3/4

Claims (3)

【特許請求の範囲】[Claims] （１）平板を摺曲させるととなく平板表面に溝部を設は
気液混合熱交換流体の流路とし、こｔを多数積層一体化
し、海部に一個または複数個の任意の形状の凸部を設け
、その一部またはすべての凸部の先端が積層される平板
の相対する面と離間させた積層式熱交換器。(1) Instead of sliding the flat plate, grooves are provided on the surface of the flat plate to serve as flow paths for the gas-liquid mixed heat exchange fluid, and a large number of these grooves are laminated and integrated, and one or more protrusions of arbitrary shape are formed in the sea area. A laminated heat exchanger in which the tips of some or all of the convex portions are separated from the opposing surfaces of the laminated plates. （２）凸部は流ガ方向に却１長い形状を鳴シ、流路方向
に平行またはある角度を持つごとく配置した特許請求の
範囲第１項記載の積層式熱交換器。(2) The stacked heat exchanger according to claim 1, wherein the convex portion has a relatively elongated shape in the direction of the flow path, and is arranged so as to be parallel to the direction of the flow path or at a certain angle. （３）凸部が流路方向に対する角度を流路に沿って変化
させた特許請求の範囲第１項記載の積層式熱交換器。(3) The laminated heat exchanger according to claim 1, wherein the convex portion has an angle with respect to the flow path direction that changes along the flow path.