JPH10206062A - Heat exchanger tube with internal groove - Google Patents
Heat exchanger tube with internal grooveInfo
- Publication number
- JPH10206062A JPH10206062A JP1292997A JP1292997A JPH10206062A JP H10206062 A JPH10206062 A JP H10206062A JP 1292997 A JP1292997 A JP 1292997A JP 1292997 A JP1292997 A JP 1292997A JP H10206062 A JPH10206062 A JP H10206062A
- Authority
- JP
- Japan
- Prior art keywords
- grooves
- groove
- pipe
- heat transfer
- tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は家庭用及び業務用エ
アコン等の冷凍空調機器に使用される空冷式熱交換器等
の凝縮器及び蒸発器に使用され、管内面に溝を形成した
内面溝付伝熱管に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for condensers and evaporators such as air-cooled heat exchangers used for refrigeration and air-conditioning equipment such as home and commercial air conditioners, and has an inner surface groove formed on the inner surface of a pipe. Heat transfer tube attached.
【０００２】[0002]
【従来の技術及びその問題点】空冷式熱交換器の凝縮器
には、管内面に螺旋状の溝を形成して熱伝達効率を向上
させた内面溝付伝熱管が使用されている。そして、この
内面溝付伝熱管の伝熱効率を向上させるために、溝の深
さを深くする深溝化、溝のリード角度を大きくする高リ
ード角化及び溝の数を増やす多溝化等の手段が採用され
ている。2. Description of the Related Art In a condenser of an air-cooled heat exchanger, a heat transfer tube with an inner surface groove having a spiral groove formed in the inner surface of the tube to improve heat transfer efficiency is used. In order to improve the heat transfer efficiency of the heat transfer tube with inner grooves, means for increasing the depth of the groove, increasing the lead angle of the groove, increasing the lead angle, and increasing the number of grooves, etc. Has been adopted.
【０００３】しかし、深溝化しようとすると、内面溝付
管の生産速度が低下してしまうと共に、工具寿命が短く
なるという欠点がある。また、伝熱管を熱交換器に組み
立てる際には、平行に配置した複数個のフィンの孔に、
伝熱管を挿通した後、この伝熱管を拡開してフィンと伝
熱管とを接合する。この拡開工程においては、伝熱管の
内側にマンドレルを配置して伝熱管を機械的に拡管す
る。このため、溝の深さを深くすると、山形状がつぶれ
やすく、熱交換器として期待する性能を得にくい。[0003] However, when the groove is to be deepened, there are disadvantages that the production speed of the inner grooved pipe is reduced and the tool life is shortened. Also, when assembling the heat transfer tube to the heat exchanger, the holes of a plurality of fins arranged in parallel,
After the heat transfer tube is inserted, the heat transfer tube is expanded to join the fin and the heat transfer tube. In this expanding step, a mandrel is arranged inside the heat transfer tube to mechanically expand the heat transfer tube. For this reason, if the depth of the groove is increased, the mountain shape is easily collapsed, and it is difficult to obtain the performance expected as a heat exchanger.
【０００４】また、高リード角化すると、凝縮性能は向
上するものの、圧力損失が著しく増大する。このため、
この熱交換器を組み込んだ空調機等の入力動力を増加さ
せたり、空気等の温度差が小さくなる。従って、熱交換
器としての性能も低下する。When the lead angle is increased, the condensation performance is improved, but the pressure loss is significantly increased. For this reason,
The input power of an air conditioner or the like incorporating the heat exchanger is increased, and the temperature difference between air and the like is reduced. Therefore, the performance as a heat exchanger also decreases.
【０００５】更に、多溝化は溝形状が複雑になるため、
製造が煩雑である。そして、極端に多溝化した場合に
は、溝間に形成される凝縮液滞留可能空間の断面積が小
さくなり、凝縮液の排出性が低下し、その結果、凝縮性
能が低下する。[0005] Further, since the multi-groove structure has a complicated groove shape,
The production is complicated. When the number of grooves is extremely increased, the cross-sectional area of the condensed liquid stagnation space formed between the grooves is reduced, and the condensed liquid dischargeability is reduced. As a result, the condensing performance is reduced.
【０００６】一方、多溝化は前記溝間に滞留する媒体液
の深さを深くする。このため、伝熱管を蒸発器に使用す
ると、蒸発時の媒体液の液膜が厚くなり、蒸発性能を低
下させる。On the other hand, the increase in the number of grooves increases the depth of the medium liquid retained between the grooves. For this reason, when the heat transfer tube is used for the evaporator, the liquid film of the medium liquid at the time of evaporation becomes thick, and the evaporation performance is reduced.
【０００７】更にまた、溝の山形状を特定してフィンの
潰れを抑制する方法がある（特開平４−２６０７９３号
公報）が、山頂幅が小さく、山頂角が小さい場合は、フ
ィンが倒れて所定の性能が得られない。一方、山頂幅を
広くした場合は、必然的に溝間の断面積が小さくなり、
凝縮性能及び蒸発性能が低下する。Furthermore, there is a method of suppressing the fin collapse by specifying the crest shape of the groove (Japanese Patent Laid-Open No. Hei 4-260793). However, when the crest width is small and the crest angle is small, the fin falls down. The specified performance cannot be obtained. On the other hand, when the peak width is widened, the cross-sectional area between the grooves inevitably decreases,
The condensation performance and the evaporation performance are reduced.
【０００８】本発明はかかる問題点に鑑みてなされたも
のであって、凝縮及び蒸発の双方において伝熱性能が優
れており、圧力損失が低く製造も容易である内面溝付伝
熱管を提供することを目的とする。The present invention has been made in view of the above problems, and provides a heat transfer tube with an inner surface groove which has excellent heat transfer performance in both condensation and evaporation, has low pressure loss, and is easy to manufacture. The purpose is to:
【０００９】[0009]
【課題を解決するための手段】本発明に係る内面溝付伝
熱管は、管内面に管軸方向に傾斜する螺旋状の複数の平
行溝を形成した内面溝付管において、溝の方向と軸方向
とがなすリード角が２０乃至４５°であり、管内面を管
円周方向にｍ（ｍは整数）等分した位置にそのｍ等分の
位置のうちのｎ（ｎは整数）個の位置を除いて前記溝の
山が形成されており、前記ｎは３以上であることを特徴
とする。An inner grooved heat transfer tube according to the present invention is an inner grooved tube in which a plurality of spiral parallel grooves inclined in the axial direction are formed on the inner surface of the tube. The lead angle formed by the direction is 20 to 45 °, and n (n is an integer) of the m equally divided positions are obtained by dividing the inner surface of the tube by m (m is an integer) in the circumferential direction of the tube. The crest of the groove is formed except for the position, and the n is 3 or more.
【００１０】本発明に係る内面溝付伝熱管は、リード角
を２０乃至４５°と大きくしたので、凝縮性能が優れて
いる。しかし、このようにリード角を大きくすると、管
内部を通流する媒体の圧力損失が大きくなるが、本発明
においては、ｍ個の位置のうち、ｎ個の位置を間引いて
溝の山が形成されている。従って、溝の数はｍ個の位置
の全てに溝を形成した場合に比して少なく、このため、
圧力損失は溝の数がｍ個の場合に比して軽減され、リー
ド角を大きくした場合の圧力損失の増大を相殺する。ま
た、本発明においては、単に、管内周面をｍ−ｎ等分し
たのではなく、ｍ等分した位置にｍ−ｎ個の溝を配置し
ている。このため、溝間に形成される媒体滞留可能空間
の断面形状は、管内周長をＬとすると、その底部の円周
方向長さがＬ／ｍのものと、底部の円周方向長さが２Ｌ
／ｍの部分とが混在している。この円周方向長さが短い
方の溝は凝縮性能は十分であるが、蒸発性能が低下す
る。しかし、円周方向の長さが長い方の溝は蒸発液を薄
く広く滞留させ、薄い液膜を形成する。このため、蒸発
性能は、この円周方向の長さが長い方の溝にて確保さ
れ、結局、凝縮性能及び蒸発性能の双方が優れたものと
なる。The heat transfer tube with an inner groove according to the present invention has a large lead angle of 20 to 45 °, and thus has excellent condensation performance. However, when the lead angle is increased in this manner, the pressure loss of the medium flowing through the inside of the tube increases. However, in the present invention, the n-points are thinned out of the m-positions to form the groove peaks. Have been. Therefore, the number of grooves is smaller than the case where grooves are formed in all of the m positions.
The pressure loss is reduced as compared with the case where the number of grooves is m, and offsets the increase in pressure loss when the lead angle is increased. Further, in the present invention, mn grooves are arranged at positions where the inner circumferential surface of the tube is not simply divided into mn equal parts, but at m equal parts. For this reason, as for the cross-sectional shape of the medium storable space formed between the grooves, assuming that the inner circumferential length of the tube is L, the circumferential length of the bottom at the bottom is L / m, and the circumferential length of the bottom at the bottom is L / m. 2L
/ M part is mixed. The groove having the shorter circumferential length has sufficient condensation performance, but the evaporation performance is reduced. However, the groove having a longer circumferential length allows the evaporating liquid to stay thin and wide, forming a thin liquid film. For this reason, the evaporation performance is ensured by the groove having the longer circumferential length, and as a result, both the condensation performance and the evaporation performance are excellent.
【００１１】[0011]
【発明の実施の形態】以下、本発明の実施例について添
付の図面を参照して具体的に説明する。図１は本発明の
実施例に係る内面溝付伝熱管の横断面を示す図である。
管内面に２種類の溝１、２が形成されている。溝の山高
さは全ての溝について共通である。管内周長をＬとする
と、管内周を円周方向にｍ等分した位置のうち、ｎ個の
位置を除いた位置に、溝の山３が形成されており、従っ
て、ｍ−ｎ個の山３が管内周に沿ってＬ／ｍのピッチで
形成されている。これにより、山３間に挟まれて形成さ
れる溝１は管内周方向に沿う長さでＬ／ｍのピッチで形
成され、溝２は２Ｌ／ｍのピッチで形成されている。即
ち、管内周面には、溝底部の管円周方向に沿う長さがＬ
／ｍの溝１と、２Ｌ／ｍの溝２とが形成される。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a view showing a cross section of a heat transfer tube with an inner groove according to an embodiment of the present invention.
Two types of grooves 1 and 2 are formed on the inner surface of the tube. The peak height of the groove is common to all the grooves. Assuming that the inner circumferential length of the pipe is L, the grooves 3 are formed at positions other than n positions among the positions obtained by equally dividing the inner circumference of the pipe by m in the circumferential direction. The peaks 3 are formed at a pitch of L / m along the inner circumference of the pipe. As a result, the grooves 1 formed between the peaks 3 are formed at a pitch of L / m along the inner circumferential direction of the pipe, and the grooves 2 are formed at a pitch of 2 L / m. That is, the length of the groove bottom along the pipe circumferential direction is L on the inner circumferential surface of the pipe.
/ M groove 1 and 2L / m groove 2 are formed.
【００１２】そして、溝１，２のリード角は２０乃至４
５°である。図２は横軸にリード角をとり、縦軸に凝縮
熱伝達率をとって、両者の関係を示すグラフ図である。
図２において、□は管内周を５０位置に等分し、この５
０位置のうちから４位置を除いて溝を配置した実施例で
ある。一方、●は従来と同様に管内周を５０位置に等分
し、各位置に溝を設けた比較例である。この図２に示す
ように、リード角が大きくなるほど、熱伝達率は高くな
る。当然、溝の数が多い比較例の方が、全てのリード角
で高い凝縮熱伝達係数を示すが、従来の内面溝付伝熱管
のリード角は１３乃至１８°程度である。この場合の凝
縮熱伝達係数に比して、本発明においては、リード角を
大きくすることにより凝縮熱伝達係数の上昇を図ってい
る。リード角が２０°未満では従来の５０個の溝を有す
る内面溝付管（比較例）より凝縮熱伝達率が劣り、リー
ド角が４５°を超えると、生産性が低下するという欠点
がある。このため、リード角は２０乃至４５°とする。The lead angles of the grooves 1 and 2 are 20 to 4
5 °. FIG. 2 is a graph showing the relationship between the lead angle on the horizontal axis and the heat transfer coefficient of condensation on the vertical axis.
In FIG. 2, □ equally divides the inner circumference of the pipe into 50 positions.
This is an embodiment in which grooves are arranged except for four positions from among zero positions. On the other hand, ● represents a comparative example in which the inner circumference of the pipe is equally divided into 50 positions and grooves are provided at each position as in the conventional case. As shown in FIG. 2, the heat transfer coefficient increases as the lead angle increases. Naturally, the comparative example having a larger number of grooves shows a higher condensation heat transfer coefficient at all lead angles, but the lead angle of the conventional heat transfer tube with an inner groove is about 13 to 18 °. In the present invention, the condensation heat transfer coefficient is increased by increasing the lead angle as compared with the condensation heat transfer coefficient in this case. When the lead angle is less than 20 °, the condensed heat transfer coefficient is inferior to that of the conventional inner grooved tube having 50 grooves (comparative example), and when the lead angle exceeds 45 °, the productivity is reduced. Therefore, the lead angle is set to 20 to 45 °.
【００１３】図３は横軸に溝深さをとり、縦軸に凝縮熱
伝達率をとって、溝深さと凝縮熱伝達率との関係を示す
グラフ図である。図中、●はリード角が２５°の場合の
実施例、□はリード角が１５°の場合の比較例である。
この図に示すように、溝深さが深くなるほど、凝縮熱伝
達率が高くなる。そして、リード角が２５°の場合の凝
縮熱伝達率は溝深さに対する依存性が低く、全ての溝深
さで安定して高い凝縮熱伝達率を有している。これは、
リード角を大きくとることにより、リード角が凝縮性能
に寄与する割合が溝深さが寄与する割合よりも大きくな
るため、図３に示すように、凝縮熱伝達率は溝深さに依
存しなくなるためである。このように、本実施例におい
ては、凝縮熱伝達率が溝深さに依存しないので、機械的
に拡管されたときに溝山が若干潰れて溝深さが浅くなっ
ても、凝縮性能には殆ど影響しない。FIG. 3 is a graph showing the relationship between the groove depth and the condensed heat transfer coefficient by taking the groove depth on the horizontal axis and the condensed heat transfer coefficient on the vertical axis. In the figure, ● represents an example in which the lead angle is 25 °, and □ represents a comparative example in which the lead angle is 15 °.
As shown in this figure, the deeper the groove depth, the higher the condensation heat transfer coefficient. When the lead angle is 25 °, the condensation heat transfer coefficient has a low dependence on the groove depth, and has a stable and high condensation heat transfer coefficient at all groove depths. this is,
By increasing the lead angle, the rate at which the lead angle contributes to the condensation performance becomes greater than the rate at which the groove depth contributes, and as shown in FIG. 3, the condensation heat transfer coefficient does not depend on the groove depth. That's why. As described above, in the present embodiment, since the condensation heat transfer coefficient does not depend on the groove depth, even if the groove hill is slightly collapsed and the groove depth becomes shallow when mechanically expanded, the condensation performance is not improved. Has little effect.
【００１４】また、溝の円周方向長さが長い溝の数ｎは
３以上であることが必要である。この間引く溝の数ｎが
３未満である場合は、薄い液膜を形成することによる蒸
発性能の向上効果が得られない。このため、ｎは３以上
とする。It is necessary that the number n of the grooves having a long circumferential length is 3 or more. If the number n of the thinned grooves is less than 3, the effect of improving the evaporation performance by forming a thin liquid film cannot be obtained. For this reason, n is set to 3 or more.
【００１５】本発明の実施例に係る内面溝付伝熱管にお
いては、リード角を高くしているので、凝縮性能が優れ
ていると共に、溝の山の一部を間引いているので、リー
ド角を高くしたことによる圧力損失の増大を相殺して、
圧力損失を軽減することができる。また、溝山の一部を
間引くことにより溝底の円周方向長さが長い溝を一部に
設けるので、溝内に液厚が薄い媒体膜を形成することが
でき、蒸発性能を向上させることができる。In the heat transfer tube with an inner surface groove according to the embodiment of the present invention, the lead angle is increased, so that the condensation performance is excellent. In addition, since a part of the groove is thinned out, the lead angle is reduced. Offset the increase in pressure loss due to the higher
Pressure loss can be reduced. In addition, since a groove having a long circumferential length at the bottom of the groove is partially provided by thinning out a part of the groove mountain, a medium film having a small liquid thickness can be formed in the groove, and the evaporation performance is improved. be able to.
【００１６】[0016]
【発明の効果】以上説明したように、本発明によれば、
リード角を大きくすると共に、溝の山ピッチが小さい溝
と、山ピッチの大きい溝とを混在させるので、凝縮性能
が優れていると共に、蒸発性能が優れており、製造が容
易である内面溝付伝熱管を得ることができる。As described above, according to the present invention,
Since the lead angle is increased and a groove with a small mountain pitch and a groove with a large mountain pitch are mixed, an inner groove with excellent condensation performance and excellent evaporation performance is easy to manufacture. Heat transfer tubes can be obtained.
【図１】本発明の実施例に係る内面溝付伝熱管の断面を
示す図である。FIG. 1 is a view showing a cross section of a heat transfer tube with an inner surface groove according to an embodiment of the present invention.
【図２】リード角と熱伝達率との関係を示すグラフ図で
ある。FIG. 2 is a graph showing a relationship between a lead angle and a heat transfer coefficient.
【図３】溝深さと凝縮熱伝達率との関係を示すグラフ図
である。FIG. 3 is a graph showing a relationship between a groove depth and a condensation heat transfer coefficient.
１、２：溝 ２：山 1, 2: groove 2: mountain
Claims (1)
数の平行溝を形成した内面溝付管において、溝の方向と
軸方向とがなすリード角が２０乃至４５°であり、管内
面を管円周方向にｍ（ｍは整数）等分した位置にそのｍ
等分の位置のうちのｎ（ｎは整数）個の位置を除いて前
記溝の山が形成されており、前記ｎは３以上であること
を特徴とする内面溝付伝熱管。An inner grooved tube having a plurality of helical parallel grooves inclined in the tube axis direction on the inner surface of the tube, wherein a lead angle between the groove direction and the axial direction is 20 to 45 °, At the position where the surface is equally divided in the pipe circumferential direction by m (m is an integer).
An inner grooved heat transfer tube characterized in that the groove peaks are formed except for n (n is an integer) positions among the equally divided positions, and the n is 3 or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01292997A JP3747974B2 (en) | 1997-01-27 | 1997-01-27 | Internal grooved heat transfer tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01292997A JP3747974B2 (en) | 1997-01-27 | 1997-01-27 | Internal grooved heat transfer tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10206062A true JPH10206062A (en) | 1998-08-07 |
| JP3747974B2 JP3747974B2 (en) | 2006-02-22 |
Family
ID=11819009
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01292997A Expired - Lifetime JP3747974B2 (en) | 1997-01-27 | 1997-01-27 | Internal grooved heat transfer tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3747974B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002005588A (en) * | 2000-06-22 | 2002-01-09 | Sumitomo Light Metal Ind Ltd | Inner helically grooved tube and its manufacturing method |
| JP2006162100A (en) * | 2004-12-02 | 2006-06-22 | Sumitomo Light Metal Ind Ltd | Heat transfer tube with inner helical groove for high pressure refrigerant |
| EP2213953A1 (en) * | 2007-11-28 | 2010-08-04 | Mitsubishi Electric Corporation | Air conditioning apparatus |
| CN103968699A (en) * | 2014-05-21 | 2014-08-06 | 合肥华凌股份有限公司 | Heat exchange tube, evaporator assembly, condenser assembly and refrigeration equipment |
-
1997
- 1997-01-27 JP JP01292997A patent/JP3747974B2/en not_active Expired - Lifetime
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002005588A (en) * | 2000-06-22 | 2002-01-09 | Sumitomo Light Metal Ind Ltd | Inner helically grooved tube and its manufacturing method |
| JP4632487B2 (en) * | 2000-06-22 | 2011-02-16 | 住友軽金属工業株式会社 | Internal grooved heat transfer tube and manufacturing method thereof |
| JP2006162100A (en) * | 2004-12-02 | 2006-06-22 | Sumitomo Light Metal Ind Ltd | Heat transfer tube with inner helical groove for high pressure refrigerant |
| JP4651366B2 (en) * | 2004-12-02 | 2011-03-16 | 住友軽金属工業株式会社 | Internal grooved heat transfer tube for high-pressure refrigerant |
| EP2213953A1 (en) * | 2007-11-28 | 2010-08-04 | Mitsubishi Electric Corporation | Air conditioning apparatus |
| EP2213953A4 (en) * | 2007-11-28 | 2014-01-08 | Mitsubishi Electric Corp | Air conditioning apparatus |
| US9651314B2 (en) | 2007-11-28 | 2017-05-16 | Mitsubishi Electric Corporation | Air conditioner with grooved inner heat exchanger tubes and grooved outer heat exchanger tubes |
| US9664455B2 (en) | 2007-11-28 | 2017-05-30 | Mitsubishi Electric Corporation | Air conditioner with internally grooved heat exchanger tubes optimized for an indoor heat exchanger and an outdoor heat exchanger |
| US9664456B2 (en) | 2007-11-28 | 2017-05-30 | Mitsubishi Electric Corporation | Air conditioner |
| US9714795B2 (en) | 2007-11-28 | 2017-07-25 | Mitsubishi Electric Corporation | Air conditioner |
| US9791218B2 (en) | 2007-11-28 | 2017-10-17 | Mitsubishi Electric Corporation | Air conditioner with grooved inner heat exchanger tubes and grooved outer heat exchanger tubes |
| CN103968699A (en) * | 2014-05-21 | 2014-08-06 | 合肥华凌股份有限公司 | Heat exchange tube, evaporator assembly, condenser assembly and refrigeration equipment |
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|---|---|
| JP3747974B2 (en) | 2006-02-22 |
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