The present invention relates to a heat exchanger.
Conventional heat exchangers used in an air conditioner or the like include a small-diameter heat transfer tube unit that is formed by stacking heat transfer fin plates (see, for example, Patent Literature 1 (Japanese Unexamined Patent Application Publication No. 2006-90636) and the like).
When a heat exchanger is used as an evaporator in a low temperature environment, frosting may concentratedly occur in a part of the heat exchanger due to internal heat flux distribution. Then, blockage of an air passage may occur in the part where frosting has concentratedly occurred, and the performance of the heat exchanger may decrease.
A heat exchanger according to one or more embodiments includes a heat transfer unit in which a heat transfer channel portion and auxiliary heat transfer portions, each of which extends in a first direction, are formed so as to be arranged in a second direction that intersects with or is perpendicular to the first direction. In the heat transfer unit, when seen in the first direction, a first auxiliary heat transfer portion that is one of the auxiliary heat transfer portions is formed at an end portion in the second direction. A first length of the first auxiliary heat transfer portion to a heat transfer channel portion that is adjacent in the second direction is larger than a distance between heat transfer channel portions that are adjacent to each other in the second direction in a case where a plurality of heat transfer channel portions exist in the heat transfer unit, or is larger than a distance between heat transfer units that are adjacent to each other in a third direction that is different from both of the first direction and the second direction in a case where a plurality of the heat transfer units are arranged in the third direction. Such a configuration can optimize the heat exchange performance of the entirety of the heat exchanger.
In a heat exchanger according to a one or more embodiments, the heat transfer unit is a unit in which the heat transfer channel portion and the auxiliary heat transfer portions are integrally formed by extrusion of aluminum. Such a heat exchanger can be easily manufactured.
In a heat exchanger according to one or more embodiments, when seen in the first direction, a thickness of each of the auxiliary heat transfer portions is smaller than twice a thickness of the heat transfer channel portion. Such a heat exchanger can be designed to be compact.
In a heat exchanger according to one or more embodiments, the first length S satisfies a condition of formula (1) below, where t is a thickness of the first auxiliary heat transfer portion when seen in the first direction. Heat exchange performance can be optimized when such a condition is satisfied.
s>11√{square root over (t)} (1)
In a heat exchanger according to one or more embodiments, in the case where a plurality of the heat transfer units are arranged in the third direction, when seen in the first direction, a position of the heat transfer channel portion of one of the heat transfer units in the second direction and a position of the auxiliary heat transfer portion of an adjacent one of the heat transfer units in the second direction are arranged so as to overlap. Such a configuration can increase the heat exchange performance of the entirety of the heat exchanger.
In a heat exchanger according to one or more embodiments, a thickness t of the first auxiliary heat transfer portion when seen in the first direction is smaller than ½ of an imaginary outside diameter D of the heat transfer channel portion. The distance FP between the heat transfer units that are adjacent to each other in the third direction in the case where a plurality of the heat transfer units is arranged in the third direction satisfies a condition of formula (2) below. Heat exchange performance can be optimized when such a condition is satisfied.
In a heat exchanger according to one or more embodiments, the heat transfer channel portion includes an airflow-upstream portion, a middle portion, and an airflow-downstream portion from the end portion side in the second direction. A thickness of the heat transfer channel portion increases from the airflow-upstream portion toward the middle portion, and the thickness decreases from the middle portion toward the airflow-downstream portion. Such a configuration can make the heat flow rate distribution of air that passes through the inside of heat transfer unit uniform.
In a heat exchanger according to one or more embodiments, the heat transfer channel portion includes a plurality of pipes. Such a configuration enables a channel having an optimal channel cross-sectional area to be easily formed.
In a heat exchanger according to one or more embodiments, in the heat transfer channel portion, a cross-sectional area of a pipe formed in the airflow-upstream portion and/or the airflow-downstream portion is smaller than a cross-sectional area of a pipe formed in the middle portion.
In a heat exchanger according to one or more embodiments, in the second direction, a length of the airflow-upstream portion is smaller than a length of the airflow-downstream portion. Such a configuration can reduce a dead water zone.
In a heat exchanger according to one or more embodiments, in a case where a plurality of the heat transfer units are arranged in the third direction, a distance between a position of an end portion of one of the heat transfer units in the second direction and a position of an end portion of another of the heat transfer units in the second direction is larger than or equal to FP/4, where FP is the distance between the heat transfer units in the third direction. Such a configuration can make the heat flow rate distribution of air that passes through the inside of heat transfer unit uniform.
An air conditioner according to one or more embodiments includes the heat exchanger according to the above embodiments.
Hereafter, embodiments of a heat exchanger and an air conditioner will be described with reference to the drawings.
(1) Overview of Heat Exchanger
A heat exchanger 10 performs heat exchange between a fluid that flows inside and air that flows outside. For example, as conceptually illustrated in
(2) Details of Heat Exchanger
(2-1) Overall Configuration
As illustrated in
The heat transfer unit group 15 includes a plurality of heat transfer units 30. The heat transfer unit group 15 is disposed so that airflow generated by the fan 6 passes through spaces between the heat transfer units 30. Details of the arrangement of these members will be described below.
(2-2) Header
As illustrated in
As illustrated in
(2-3) Heat Transfer Unit
(2-3-1)
As illustrated in
For convenience of description, it is assumed that the first direction D1, the second direction D2, and the third direction D3 are perpendicular to each other. However, these directions D1 to D3 need not be completely perpendicular to each other, and it is possible to realize the heat exchanger 10 according to one or more embodiments as long as these directions intersect with each other.
The heat transfer unit 30 is connected to the first header 21 and the second header 22 at the connection surfaces 21S and 22S of the first header 21 and the second header 22. To be specific, as illustrated in
The heat transfer channel portion 31 enables a refrigerant to move between the first header 21 and the second header 22. To be specific, a substantially cylindrical passage is formed in the heat transfer channel portion 31, and the refrigerant moves in the passage. The heat transfer channel portion 31 according to one or more embodiments has a linear shape in the first direction D1.
The auxiliary heat transfer portion 32 accelerates heat exchange between a refrigerant that flows in adjacent heat transfer channel portions 31 and ambient air. Here, as with the heat transfer channel portion 31, the auxiliary heat transfer portion 32 is formed so as to extend in the first direction D1 and is disposed so as to be in contact with the adjacent heat transfer channel portions 31. The auxiliary heat transfer portion 32 may be integrally formed with or may be independently formed from the heat transfer channel portions 31.
(2-3-2)
Referring to
In the heat transfer unit 30 according to one or more embodiments, when seen in the first direction D1, a first auxiliary heat transfer portion 32g (including 32ag and 32bg), which is one of the auxiliary heat transfer portions 32, is formed at an end portion in the second direction D2. The first auxiliary heat transfer portion 32g is configured so that a first length S to a heat transfer channel portion 31g (including 31ag and 31bg) that is adjacent in the second direction D2 is larger than the distance PP between other heat transfer channel portions 31 of the heat transfer unit 30 that are adjacent to each other in the second direction D2 (see
The first length S in one heat transfer unit 30a is larger than the distance FP between heat transfer units 30a and 30b that are adjacent in the third direction D3.
When seen in the first direction D1, the position of a heat transfer channel portion 31a of one of the heat transfer units 30a in the second direction and the position of an auxiliary heat transfer portion 32b of an adjacent heat transfer unit 30b in the second direction D2 are arranged so as to overlap. In other words, as illustrated in
As illustrated in
When seen in the first direction D1, the thickness t1 of the auxiliary heat transfer portion 32 is smaller than twice the thickness of an outer wall member w of the heat transfer channel portion 31 (see
(2-4) Refrigerant Channel
When the heat exchanger 10 is used as an evaporator, airflow W that is generated by the fan 6 flows in the second direction D2 as illustrated in
When the heat exchanger 10 is used as a condenser, the refrigerant F flows in a direction opposite from that when the heat exchanger 10 is used as an evaporator. That is, the refrigerant F in a gas phase flows through the first pipe 41 to the heat exchanger 10, and the refrigerant F in a liquid phase flows through the second pipe 42 out from the heat exchanger 10.
(3) Method of Manufacturing Heat Exchanger 10
The heat transfer unit 30 is manufactured from, for example, a metal material such as aluminum or an aluminum alloy. To be specific, first, extrusion of a metal material is performed by using a die corresponding to the cross-sectional shape of
The first header 21 and the second header 22 are manufactured by processing a metal material into a tubular shape. Coupling holes for inserting the end portions 31e of the heat transfer channel portions 31 are formed in the first header 21 and the second header 22. The coupling holes are circular through-holes that are formed by using, for example, a drill.
In assembling the heat exchanger 10, the end portions 31e of the heat transfer channel portions 31 of the heat transfer units 30 are inserted into the coupling holes of the first header 21 and the second header 22. Thus, the end portions 32e of the auxiliary heat transfer portions 32 are brought into contact with the connection surfaces 21S and 22S of the first header 21 and the second header 22. At the contact portions, the heat transfer units 30, the first header 21, and the second header 22 are fixed by, for example, brazing.
(4) Features
(4-1)
As heretofore described, the heat exchanger 10 according to one or more embodiments includes the heat transfer unit 30 in which the heat transfer channel portions 31 and the auxiliary heat transfer portions 32, each of which extends in the first direction D1, are formed so as to be arranged in the second direction D2 that intersects with or is perpendicular to the first direction D1. Here, a plurality of heat transfer units 30 are arranged in the third direction D3 that is different from both of the first direction D1 and the second direction D2, and form the heat transfer unit group 15.
In the heat transfer unit 30, when seen in the first direction D1, the first auxiliary heat transfer portion 32g, which is one of the auxiliary heat transfer portions 32, is formed at an end portion in the second direction D2. The first auxiliary heat transfer portion 32g is configured so that the first length S to the heat transfer channel portion 31g that is adjacent in the second direction D2 is larger than the distance PP between the heat transfer channel portions 31 of the heat transfer unit 30 that are adjacent to each other in the second direction D2. The heat transfer unit 30 is configured so that the first length S is larger than the distance FP between the heat transfer units 30 that are adjacent to each other in the third direction D3.
With such a heat exchanger 10, because the distance (the first length S), in the heat transfer channel portion 31g on the most airflow-upstream side, to the adjacent auxiliary heat transfer portion 32g is large, the amount of heat that is transferred from the heat transfer channel portions 31g on the most airflow-upstream side to the auxiliary heat transfer portion 32g can be reduced. Thus, heat flux distribution on the surface of the heat transfer unit 30 can be made uniform. As a result, when the heat exchanger 10 is used as an evaporator in a low temperature environment (for example, 7° C. or lower), occurrence of frosting locally at an inlet portion of the air passage can be suppressed or avoided.
The heat exchanger 10 according to one or more embodiments is not limited to the configuration described here. For example, the heat exchanger 10 may have a configuration according to any of modifications described below.
(4-2)
In the heat exchanger 10 according to one or more embodiments, when seen in the first direction D1, the position of the heat transfer channel portion 31a of one heat transfer units 30a in the second direction D2 and the position of the auxiliary heat transfer portion 32b of an adjacent heat transfer unit 30b in the second direction D2 are arranged so as to overlap. In short, in the heat exchanger 10 having such a configuration, as illustrated in
To be more specific, with the heat transfer unit group 15 having a configuration illustrated in
However, the heat exchanger 10 according to one or more embodiments does not exclude the heat transfer unit group 15X illustrated in
(4-3)
In the heat exchanger 10 according to one or more embodiments, as illustrated in
With such a configuration, the heat flux distribution of air that passes through the inside of the heat transfer unit group 15 can be made uniform. Moreover, because the end portions of the first auxiliary heat transfer portions 32g are arranged in a staggered pattern, a portion having a large cross-sectional area is formed at an inlet part of the air passage. Accordingly, when the heat exchanger 10 is used as an evaporator, the generation amount of frost can be suppressed. As a result, blockage of the air passage due to frosting can be avoided.
(4-4)
The heat exchanger 10 according to one or more embodiments further includes the first header 21 (upper header) and the second header 22 (lower header) that are connected to the heat transfer units 30 from above and below in the first direction D1 and that form a part of the refrigerant channel. With such a configuration, the longitudinal direction of the heat transfer units 30 can be directed in the vertical direction, and water adhered to the heat transfer units 30 (due condensation water and the like) can be easily discharged. Moreover, ease of assembling and processing can be also increased.
However, the heat exchanger 10 according to one or more embodiments does not exclude a configuration such that the first header 21 and the second header 22 are arranged in the left-right direction instead of the up-down direction.
(4-5)
In the heat exchanger 10 according to one or more embodiments, each heat transfer unit 30 can be formed from a single member by extrusion of a metal material. The plurality of cutouts 33 can be simultaneously formed by punching. Accordingly, it is possible to provide the heat exchanger 10 that can be easily assembled and processed. For example, as such a heat transfer unit 30, a unit in which the heat transfer channel portions 31 and the auxiliary heat transfer portions 32 are integrally formed by extrusion of aluminum can be used.
(4-6)
In the heat transfer unit 30 according to one or more embodiments, when seen in the first direction D1, the thickness t1 of the auxiliary heat transfer portion 32 is smaller than twice the thickness w of the heat transfer channel portion 31. For example, such a configuration can be realized by forming the heat transfer unit 30 by extrusion. When the thickness t1 of the auxiliary heat transfer portion 32 is smaller than twice the thickness w of the heat transfer channel portion 31, the first length S of the first auxiliary heat transfer portion 31g can be shortened, compared with other configurations. As a result, the size of the heat exchanger 10 can be reduced.
To be more specific, in a heat transfer unit that is formed by stacking two fin plates having a substantially uniform thickness, the thickness w of the auxiliary heat transfer portion 32 is twice the thickness t1 of the heat transfer channel portion 31. Therefore, in order to provide the heat transfer channel portion 31 with sufficient pressure resistance, the thickness t1 of the auxiliary heat transfer portions 32 increases. When the thickness t1 increases, frosting becomes more likely to occur at a distal end portion of the auxiliary heat transfer portion 32 on the airflow-upstream side (the first auxiliary heat transfer portion 32g). In order to avoid frosting, it is necessary to increase the first length S of the first auxiliary heat transfer portion 32. In contrast, when the heat transfer units 30 is formed by extrusion, sufficient pressure resistance can be provided even if the thickness of the heat transfer channel portions 31 is reduced. As a result, the first length S can be shortened, and the size of the heat exchanger can be reduced.
(5) Modifications
(5-1) Modification A
Although the heat exchanger 10 according to one or more embodiments includes the heat transfer unit group 15 having a configuration described above, the heat exchanger 10 is not limited to such a configuration.
The heat exchanger 10 according to one or more embodiments may have any configuration such that the first length S, in the first auxiliary heat transfer portion 32g, to a heat transfer channel portion 31g that is adjacent in the second direction D2 is larger than the distance PP between the heat transfer channel portions 32 that are adjacent to each other in the second direction D2, in a case where a plurality of heat transfer channel portions 31 exist in the heat transfer units 30. In other words, in the heat exchanger 10 according to one or more embodiments, the heat transfer units 30 need not be arranged in the third direction D3. Also with such a configuration, because the first length S of the heat transfer channel portion 31g on the most airflow-upstream side is large, the amount of heat transferred from the heat transfer channel portion 31g on the most airflow-upstream side to the auxiliary heat transfer portion 32g can be reduced.
The heat exchanger 10 according to one or more embodiments may have any configuration such that the first length S of the first auxiliary heat transfer portion 32g is larger than the distance FP between the heat transfer units 30a and 30b that are adjacent to each other in the third direction D3 in a case where a plurality of heat transfer units 30 are arranged in the third direction D3 that is different from both of the first direction D1 and the second direction D2. In other words, in the heat exchanger 10 according to one or more embodiments, a plurality of heat transfer channel portions 31 need not exist in the heat transfer unit 30. Also with such a configuration, because the distance between the heat transfer channel portion 31g on the most airflow-upstream side and an adjacent auxiliary heat transfer portion 32g (first length S) is large, the amount of heat transferred from the heat transfer channel portion 31g on the most airflow-upstream side to the auxiliary heat transfer portion 32g can be reduced.
(5-2) Modification B
In the heat exchanger 10 according to one or more embodiments, the first length S may satisfy the condition of formula (1) below, where t is the thickness of the first auxiliary heat transfer portion 32g when seen in the first direction D1. With the heat exchanger 10 that satisfies the condition of formula (1) below, heat exchange performance can be optimized. In particular, when the heat exchanger 10 is used as an evaporator, frosting can be suppressed, and air passage resistance can be optimized.
s>11√{square root over (t)} (1)
To be more specific, the inventors found that, when the condition of formula (1) is satisfied, heat flux at the distal end of the first auxiliary heat transfer portion 32g is lower than or equal to that at the vertex of the heat transfer channel portion 31g. The inventors also found that, when the condition of formula (1) is satisfied, even when the heat exchanger 10 is used as an evaporator in a low temperature environment (for example, 7° C. or lower), concentration of frosting on the distal end of the first auxiliary heat transfer portion 32g can be avoided.
For example, the inventors performed a simulation, on the assumption that the heat exchanger 10 is configured as follows: FP=2.05 mm, where FP is the distance between adjacent heat transfer units 30a and 30b; PP=1.7 mm, where PP is the distance between adjacent heat transfer channel portions 31; D=1.0 mm, where D is the imaginary outside diameter of the heat transfer channel portion; W=38 mm, where W is the length of the heat transfer unit 30 in the second direction D2; and t=0.2 mm, where t is the thickness of the first auxiliary heat transfer portion 32g. The simulation conditions were as follows: the air temperature was 7° C., the airflow speed was 1.8 m/s, the refrigerant temperature was 0° C., the heat transfer coefficient of the inside of the heat transfer channel portions 31 was 6407 W/m2·K. The inventors obtained a result that, under such conditions, as illustrated in
(5-3) Modification C
In the heat exchanger 10 according to one or more embodiments, the thickness t of the first auxiliary heat transfer portion 32g when seen in the first direction D1 may be smaller than ½ of the imaginary outside diameter D of the heat transfer channel portion 31. Here, the “imaginary outside diameter D” is defined as the outside diameter of a circular pipe that allows a refrigerant to flow therethrough at the same flow rate as the heat transfer channel portion 32. The distance FP between adjacent heat transfer units 30a and 30b in the third direction D3 when a plurality of heat transfer units 30 are arranged in the third direction D3 may satisfy the condition of formula (2) below.
The inventors examined and found that heat exchange performance can be optimized when the condition of formula (2) is satisfied. In particular, the inventors found that, when the heat exchanger 10 according to one or more embodiments is used as an evaporator, frosting can be suppressed, and air passage resistance can be optimized.
(5-4) Modification D
As illustrated in
With the heat exchanger 10 having such a configuration, when air flows from the first auxiliary heat transfer portion 32g, flow of air is guided by the airflow-upstream portion 31R and the airflow-downstream portion 31T, which exist at the front and back of the middle portion 32S, and dead water zone can be reduced. As a result, the heat flux distribution of air that passes through the inside of the heat transfer unit 30 can be made uniform. Here, the term “dead water zone” refers to a region where movement of air is inactive. If a dead water zone exists, movement of heat between air and the heat transfer unit is impeded, and the heat transfer performance of the heat exchanger 10 decreases.
The heat transfer channel portions 31 may include a plurality of pipes P. Such a configuration enables a channel having an optimal channel cross-sectional area to be easily formed. Moreover, in the heat transfer channel portion 31 including a plurality of pipes P, the cross-sectional area of pipes Pr and Pt, which are formed in the airflow-upstream portion 31R and/or the airflow-downstream portion 31T, may be smaller than the cross sectional area of a pipe Ps formed in the middle portion 31S. Thus, the heat transfer channel portion 32 including the middle portion 31S, which has a large film thickness, can be easily formed. Moreover, in the second direction D2, the length of the airflow-upstream portion 31R may be smaller than the length of the airflow-downstream portion 31T. Such a configuration can further reduce a dead water zone.
(5-5) Modification E
In the heat exchanger 10 according to one or more embodiments, the refrigerant channel may be folded back at least once in the second direction D2 in which airflow W is generated. For example, a refrigerant channel illustrated in
With such a configuration, due to pressure loss, the refrigerant temperature in the heat transfer channel portion 31 that exists on the airflow-upstream side (hereafter, also referred to as an airflow-upstream heat transfer channel portion) increases. Therefore, when the heat exchanger 10 is used as an evaporator, heat exchange amount in the airflow-upstream heat transfer channel portion is suppressed. Thus, variation of heat flux in accordance with the position in the heat transfer unit group 15 can be suppressed. As a result, when the heat exchanger 10 is used as an evaporator in a low temperature environment (for example, 7° C. or lower), local occurrence of frosting can be avoided, and a heat exchanger having high heat exchange performance can be provided.
With such a configuration, because all of the refrigerant F flowing in from the second pipe 42 can be temporarily caused to flow through the airflow-upstream heat transfer channel portion, the refrigerant is prevented from completely evaporating in the airflow-upstream heat transfer channel portion. As a result, the heat exchange performance of the heat exchanger 10 can be optimized.
(5-6) Modification F
In the heat exchanger 10 according to one or more embodiments, when seen in the first direction D1, a heat insulator I may be applied to an end portion of the heat transfer unit 30 on the airflow-upstream side in the second direction D2 (here, the auxiliary heat transfer portion 32g) (see
In the example illustrated in
To be more specific, if a hole, a cutout, or the like is formed in the auxiliary heat transfer portion 32g, water generated by defrosting may be retained in the hole, the cutout, or the like. In this case, next frosting may spread from a portion where water is retained. In contrast, with the heat exchanger 10 according to the modification F, because the auxiliary heat transfer portion 32g has a shape without a hole, a cutout, or the like, occurrence of frosting after a defrosting operation can be suppressed.
(5-7) Modification G
The heat transfer channel portion 31 according to one or more embodiments is not limited to the one described above, and may have another configuration. For example, the cross-sectional shape of the heat transfer channel portions 31 when seen in the first direction D1 may be any of: a semicircular shape, an elliptical shape, a flat shape, a shape like an upper half of an airfoil, and/or a shape like a lower half of an airfoil; or any combination of these. In short, the heat exchanger 10 may have any shape that optimizes heat exchange performance.
(5-8) Modification H
The heat transfer unit group 15 according to one or more embodiments may have a configuration as illustrated in
In the example illustrated in
Moreover, at least one heat transfer unit 30a is disposed in a direction such that, with respect to a heat transfer unit 30b adjacent on one side, a surface on which the first bulging portion 31pa is formed and a surface of the adjacent heat transfer unit 30b on which the first bulging portion 31pb is formed face each other. The heat transfer unit 30a is disposed in a direction such that, with respect to the heat transfer unit 30c adjacent on the other side, a surface on which the first flat surface portion 31qa is formed and a surface of the other heat transfer unit 30c on which the first flat surface portion 31qc is formed face each other.
With such a configuration, when the heat exchanger 10 is used as an evaporator, because airflow straightly passes through an air passage in which the first flat surface portions 31qa and 31qc face each other, the generation amount of frost can be suppressed. Thus, heat exchange performance can be increased depending on a use environment.
In an air passage in which the first bulging portions 31pa and 31pb face each other, contraction of airflow occurs, and frost is likely to concentratedly occur in the air passage. However, even if such frosting occurs, depending on a use environment, the heat exchange performance of the entirety of the heat exchanger can be increased, compared with a heat exchanger in which substantially the same bulging portions are formed on both surfaces of the heat transfer units as illustrated in
Moreover, as illustrated in
Furthermore, the heat transfer unit 30 may have a second bulging portion that bulges to a smaller degree than the first bulging portion 31p, instead of the first flat surface portion 31q. An argument similar to that described above also applies to this case.
(5-9) Modification I
The heat transfer unit group 15 according to one or more embodiments may have a configuration as illustrated in
In the example illustrated in
Moreover, at least one heat transfer unit 30a is disposed in a direction such that, with respect to a heat transfer unit 30b adjacent on one side, a surface on which the first bulging portion 31pa is formed and a surface of the adjacent heat transfer unit 30b on which the first flat portion 31qb is formed face each other. The heat transfer unit 30a is disposed in a direction such that, with respect to the heat transfer unit 30c adjacent on the other side, a surface on which the third bulging portion 31ra is formed and a surface of the other adjacent heat transfer unit 30c on which the second flat surface portion 30sc is formed face each other.
Furthermore, the first positions L1a and L1b (or L1a and L1c) in the adjacent heat transfer units 30a and 30b (or 30a and 30c) are arranged so as to overlap when seen in the first direction D1. The second positions L2a and L2b (or L2a and L2c) are arranged so as to overlap when seen in the first direction D1. To be more specific, although the “first position L1” and the “second position L2” are defined for each heat transfer unit, here, these positions are the same in the heat transfer units 30a, 30b, and 30c.
In short, in the heat exchanger 10 according to the modification I, between adjacent heat transfer units 30a and 30b, the first bulging portions 31pa and 31pb and the like do not face each other, but are formed in opposite directions. Therefore, compared with a configuration in which the first bulging portions 31pa and 31pb and the like face each other, occurrence of contraction flow can be suppressed. As a result, it is possible to suppress increase of airflow resistance, and to realize optimal heat exchange performance. With the heat exchanger 10 having a configuration described above, when used as an evaporator (for example, 7° C. or lower), local frosting can be suppressed, compared with a heat exchanger in which substantially the same bulging portions are formed on both sides of the heat transfer units as illustrated in
The heat transfer unit 30 may have a second bulging portion that bulges to a smaller degree than the first bulging portion 31p, instead of the first flat surface portion 31q. The heat transfer unit 30 may have a fourth bulging portion that bulges to a smaller degree than the third bulging portion 31r, instead of the second flat surface portion 31s. An argument similar to that described above also applies to these cases.
(5-10) Modification J
As illustrated in
(5-11) Modification K
The heat exchanger 10 according to one or more embodiments can be applied to a vessel heat exchanger (small-diameter multi-pipe heat exchanger) in which heat transfer tubes and fins are arranged in one direction. However, the heat exchanger 10 is not limited to this configuration. For example, application to a microchannel heat exchanger (flat multi-hole-pipe heat exchanger) is also possible.
Although the disclosure has been described with respect to only a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that various other embodiments may be devised without departing from the scope of the present invention. Accordingly, the scope of the invention should be limited only by the attached claims.
Number | Date | Country | Kind |
---|---|---|---|
2018-036980 | Mar 2018 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2019/006844 | 2/22/2019 | WO |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2019/167840 | 9/6/2019 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
5513432 | Sasaki | May 1996 | A |
20060237178 | Katoh et al. | Oct 2006 | A1 |
20130206376 | Shikazono | Aug 2013 | A1 |
20140027098 | Alahyari | Jan 2014 | A1 |
20160054068 | Matsuura et al. | Feb 2016 | A1 |
20200217590 | Maeda | Jul 2020 | A1 |
Number | Date | Country |
---|---|---|
3919515 | Dec 1990 | DE |
1236960 | Sep 2002 | EP |
S6183890 | Apr 1986 | JP |
2002-139282 | May 2002 | JP |
2006-084096 | Mar 2006 | JP |
2006-090636 | Apr 2006 | JP |
2006-112732 | Apr 2006 | JP |
2006-322698 | Nov 2006 | JP |
2015-117874 | Jun 2015 | JP |
9966281 | Dec 1999 | WO |
2014171095 | Oct 2014 | WO |
Entry |
---|
International Search Report issued in corresponding International Application No. PCT/JP2019/006844 dated Apr. 23. 2019 (4 pages). |
International Preliminary Report on Patentability issued in corresponding International Application No. PCT/JP2019/006844 dated Sep. 10, 2020 (13 pages). |
Extended European Search Report issued in the counterpart European Patent Application No. 19760319.4, dated Mar. 17, 2021 (6 pages). |
Number | Date | Country | |
---|---|---|---|
20210010727 A1 | Jan 2021 | US |