U.S. patent application number 14/395875 was filed with the patent office on 2015-04-16 for refrigerant distributing device and heat exchanger including the same.
This patent application is currently assigned to Mitsubishi Electric Corporation. The applicant listed for this patent is Akira Ishibashi, Sangmu Lee, Takuya Matsuda, Takashi Okazaki. Invention is credited to Akira Ishibashi, Sangmu Lee, Takuya Matsuda, Takashi Okazaki.
Application Number | 20150101363 14/395875 |
Document ID | / |
Family ID | 49482329 |
Filed Date | 2015-04-16 |
United States Patent
Application |
20150101363 |
Kind Code |
A1 |
Matsuda; Takuya ; et
al. |
April 16, 2015 |
REFRIGERANT DISTRIBUTING DEVICE AND HEAT EXCHANGER INCLUDING THE
SAME
Abstract
A header that has a configuration in which the header is
connected to one end of each of a plurality of flattened pipes of a
heat exchanger that flows a refrigerant in parallel to the
plurality of flattened pipes disposed in parallel and an interior
of the header is divided by one or more division plates in a
parallel direction in which the plurality of heat-transfer pipes
are disposed in parallel, the header being mounted so as to stand
in an up-down direction, and a distributor configured to distribute
the refrigerant to each chamber within the header divided by the
division plates, are provided.
Inventors: |
Matsuda; Takuya; (Tokyo,
JP) ; Ishibashi; Akira; (Tokyo, JP) ; Lee;
Sangmu; (Tokyo, JP) ; Okazaki; Takashi;
(Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Matsuda; Takuya
Ishibashi; Akira
Lee; Sangmu
Okazaki; Takashi |
Tokyo
Tokyo
Tokyo
Tokyo |
|
JP
JP
JP
JP |
|
|
Assignee: |
Mitsubishi Electric
Corporation
Tokyo
JP
|
Family ID: |
49482329 |
Appl. No.: |
14/395875 |
Filed: |
April 26, 2012 |
PCT Filed: |
April 26, 2012 |
PCT NO: |
PCT/JP2012/002860 |
371 Date: |
November 6, 2014 |
Current U.S.
Class: |
62/525 ; 165/174;
165/175 |
Current CPC
Class: |
F28F 9/027 20130101;
F28D 1/0417 20130101; F28F 9/0202 20130101; F25B 39/04 20130101;
F25B 2339/044 20130101; F28D 1/053 20130101; F28D 2021/0071
20130101; F25B 39/028 20130101; F28F 9/0209 20130101 |
Class at
Publication: |
62/525 ; 165/174;
165/175 |
International
Class: |
F25B 39/02 20060101
F25B039/02; F28D 1/04 20060101 F28D001/04; F28F 9/02 20060101
F28F009/02 |
Claims
1. A refrigerant distributing device comprising: a header having a
configuration in which the header is connected to one end of each
of a plurality of heat-transfer pipes of a heat exchanger that
flows a refrigerant in two-phase gas-liquid state in parallel to
the plurality of heat-transfer pipes disposed in parallel and an
interior of the header is divided, by one or more division plates,
in a parallel direction in which the plurality of heat-transfer
pipes are disposed, the header being mounted so as to stand in an
up-down direction; and a distributor configured to distribute the
refrigerant to each chamber within the header divided by the
division plates and flow the refrigerant into each chamber.
2. The refrigerant distributing device of claim 1, wherein a drift
suppression member is provided at a refrigerant inflow portion of
each chamber so as to suppress a drift of the refrigerant.
3. The refrigerant distributing device of claim 2, wherein the
drift suppression member is an orifice configured to reduce a flow
of the refrigerant.
4. The refrigerant distributing device of claim 1, wherein a
position of the division plates is set in accordance with a wind
speed distribution at the heat exchanger, and the position of the
division plate is set such that a length, in the parallel
direction, of the chamber to which the heat-transfer pipes passing
through a portion where a wind speed is high are connected is
shorter than a length, in the parallel direction, of the chamber to
which the heat-transfer pipes passing through a portion where the
wind speed is low are connected.
5. The refrigerant distributing device of claim 1, wherein the
distributor is connected to each of the respective chambers via
each of a plurality of capillary tubes that allow a flow rate of
the refrigerant to be adjusted, a distribution amount of the
refrigerant flowed into each chamber is set in accordance with a
wind speed distribution at the heat exchanger, the plurality of
capillary tubes are selected such that a distribution amount for
the chamber to which the heat-transfer pipes located at a portion
where a wind speed is high are connected is larger than a
distribution amount for the chamber to which the heat-transfer
pipes located at the portion where the wind speed is low are
connected.
6. A heat exchanger comprising a refrigerant distributing device
including a header having a configuration in which the header is
connected to one end of each of a plurality of heat-transfer pipes
of a heat exchanger that flows a refrigerant in two-phase
gas-liquid state in parallel to the plurality of heat-transfer
pipes disposed in parallel and an interior of the header is divided
by one or more division plates in a parallel direction in which the
plurality of heat-transfer pipes are disposed, the header being
mounted so as to stand in an up-down direction; and a distributor
configured to distribute the refrigerant to each chamber within the
header divided by the division plates and flow the refrigerant into
each chamber.
7. The heat exchanger of claim 6, wherein the parallel direction in
which the plurality of heat-transfer pipes are disposed is the
up-down direction, the header is mounted so as to stand in the
up-down direction, and each heat-transfer pipe is a flattened pipe
having a plurality of through holes that are refrigerant flow
paths.
8. A refrigeration cycle apparatus comprising a heat exchanger
including a refrigerant distributing device including a header
having a configuration in which the header is connected to one end
of each of a plurality of heat-transfer pipes of a heat exchanger
that flows a refrigerant in two-phase gas-liquid state in parallel
to the plurality of heat-transfer pipes disposed in parallel and an
interior of the header is divided by one or more division plates in
a parallel direction in which the plurality of heat-transfer pipes
are disposed, the header being mounted so as to stand in an up-down
direction; and a distributor configured to distribute the
refrigerant to each chamber within the header divided by the
division plates and flow the refrigerant into each chamber.
9. An air-conditioning apparatus comprising a heat exchanger
including a refrigerant distributing device including a header
having a configuration in which the header is connected to one end
of each of a plurality of heat-transfer pipes of a heat exchanger
that flows a refrigerant in two-phase gas-liquid state in parallel
to the plurality of heat-transfer pipes disposed in parallel and an
interior of the header is divided by one or more division plates in
a parallel direction in which the plurality of heat-transfer pipes
are disposed, the header being mounted so as to stand in an up-down
direction; and a distributor configured to distribute the
refrigerant to each chamber within the header divided by the
division plates and flow the refrigerant into each chamber.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a U.S. national stage application of
PCT/JP2012/002860 filed on Apr. 26, 2012, the contents of which are
incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to a refrigerant distributing
device that is mounted to a heat exchanger used in a refrigeration
cycle apparatus such as an air-conditioning apparatus and
distributes a refrigerant, and a heat exchanger including the
refrigerant distributing device, a refrigeration cycle apparatus,
and an air-conditioning apparatus.
BACKGROUND
[0003] Conventionally, there is a heat exchanger in which a pair of
headers extends in an up-down direction so as to be spaced apart
from each other in a right-left direction, a plurality of flattened
pipes are disposed in parallel between the pair of headers, and
both end portions of each of a plurality of heat exchange pipes
communicate with the pair of headers. In the case where such a heat
exchanger is used as an evaporator, a refrigerant flows thereinto
as a two-phase gas-liquid flow, and thus liquid stays in the
gravitational direction within the header at an inlet side, while
gas stays in an upper portion within the header. Thus, it is not
possible to uniformly distribute the refrigerant to each flattened
pipe, resulting in deterioration of the performance of the heat
exchanger.
[0004] Therefore, in the case where the heat exchanger is used as
an evaporator, the header at the inlet side is required to have a
function to uniformly distribute the refrigerant. As such a
refrigerant distributing device, conventionally, there is a
refrigerant distributing device in which a loop-shaped flow path is
formed within a header so as to be turned in an up-down direction,
a flow of a two-phase refrigerant having flowed therein is
circulated within the header to be made uniform, whereby the
refrigerant is distributed to each of a plurality of heat-transfer
pipes (see, e.g., Patent Literature 1).
[0005] In addition, as an evaporator that allows uniform
distribution of a refrigerant, there is an evaporator that has a
configuration in which a pair of headers extends in a right-left
direction (the horizontal direction) so as to be spaced apart from
each other and a plurality of flattened pipes are disposed in
parallel between the pair of headers, and in which a plurality of
refrigerant inlets are provided in the header at an inlet side so
as to be spaced apart from each other in the right-left direction,
and a refrigerant is jetted and flowed from each refrigerant inlet
into the header via an orifice (see, e.g., Patent Literature
2).
PATENT LITERATURE
[0006] Patent Literature 1: Japanese Unexamined Patent Application
Publication No. 2011-85324 (Abstract, FIG. 1)
[0007] Patent Literature 2: Japanese Unexamined Patent Application
Publication No. 2000-249428 (Abstract, FIG. 4)
[0008] With the structure of Patent Literature 1, although an
effect of refrigerant uniform distribution is observed at a certain
level, all of the plurality of heat-transfer pipes communicate with
each other in the interior of the header and thus are influenced in
the interior of the header by a head difference. Therefore, the
refrigerant distribution effect cannot be sufficient and further
improvement thereof is desired.
[0009] In Patent Literature 2, since the header is horizontally
mounted, the header is not influenced by a head difference.
However, in the case where the header is mounted so as to stand in
the up-down direction, a liquid is likely to stay in a lower
portion under influence of the head difference.
SUMMARY
[0010] The present invention has been made in view of such points,
and an object of the present invention is to provide a refrigerant
distributing device that is able to uniformly distribute a
refrigerant by suppressing the influence of a head difference, a
heat exchanger including the refrigerant distributing device, a
refrigeration cycle apparatus, and an air-conditioning
apparatus.
[0011] A refrigerant distributing device according to the present
invention includes: a header having a configuration in which the
header is connected to one end of each of a plurality of
heat-transfer pipes of a heat exchanger that flows a refrigerant in
two-phase gas-liquid state in parallel to the plurality of
heat-transfer pipes disposed in parallel and an interior of the
header is divided, by one or more division plates, in a parallel
direction in which the plurality of heat-transfer pipes are
disposed, the header being mounted so as to stand in an up-down
direction; and a distributor configured to distribute the
refrigerant to each chamber within the header divided by the
division plates and flow the refrigerant into each chamber.
[0012] According to the present invention, it is possible to obtain
a refrigerant distributing device that is able to uniformly
distribute a refrigerant by suppressing the influence of a head
difference. It is possible to obtain an effective effect
particularly when the header is mounted so as to stand in the
up-down direction.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a schematic perspective view of a heat exchanger
including a refrigerant distributing device according to one
embodiment of the present invention.
[0014] FIG. 2 is a schematic cross-sectional view of a portion of
the refrigerant distributing device in FIG. 1.
[0015] FIG. 3 is a perspective view showing a flattened pipe in
FIG. 1.
[0016] FIG. 4 is a diagram showing a refrigerant circuit of a
refrigeration cycle apparatus to which the heat exchanger in FIG. 1
is applied.
[0017] FIG. 5 is a diagram showing another configuration example of
the refrigerant distributing device.
[0018] FIG. 6 is a diagram illustrating the principle of
determining the height of each chamber in accordance with a wind
speed distribution.
DETAILED DESCRIPTION
[0019] FIG. 1 is a schematic perspective view of a heat exchanger
including a refrigerant distributing device according to one
embodiment of the present invention. FIG. 2 is a schematic
cross-sectional view of a portion of the refrigerant distributing
device in FIG. 1. In FIGS. 1 and 2 and the figures described below,
portions designated by the same reference signs are the same or
equivalent portions, and the same applies to the entire
specification. In addition, the forms of constituent elements
described in the entire specification are merely illustrative and
not limited to these descriptions.
[0020] A heat exchanger 1 is a parallel-flow type heat exchanger
which flows a refrigerant in parallel, and includes a pair of
headers 10 (10a, 10b) each header is spaced apart from each other
in a right-left direction and stands in an up-down direction;
[0021] and a plurality of flattened pipes (heat-transfer pipes) 20
that are disposed in parallel in the up-down direction between the
pair of headers 10 and both ends of each of which are connected to
the pair of headers 10. The heat exchanger 1 further includes a
plurality of fins 30 and a distributor 40. The pair of headers 10,
the flattened pipes 20, and the fins 30 is formed of aluminum or an
aluminum alloy. The distributor 40 is connected to the header 10a
via capillary tubes 50 and forms a refrigerant distributing device
with the header 10a.
[0022] The fins 30 are plate-shaped fins that are stacked between
the pair of headers 10 so as to be spaced apart from each other and
between which air passes. The plurality of flattened pipes 20
extend through the fins 30. The fins 30 may not necessarily be
plate-shaped fins. For example, the fins 30 may be, for example,
wave-shaped fins that are stacked in the up-down direction
alternately with the flattened pipes 20, and in short, may be fins
that are disposed so as to allow air to pass therethrough in an air
passing direction.
[0023] As shown in FIG. 3, each flattened pipe 20 has a plurality
of through holes 20a serving as refrigerant flow paths.
[0024] The interior of the header 10a is divided by one or more
division plates 11 in the up-down direction into a plurality of
chambers 12. Here, eight chambers 12 are formed by seven division
plates 11. At each chamber 12, a plurality of through holes 13 are
formed so as to be aligned in the up-down direction. The flattened
pipe 20 is connected to each through hole 13. In addition, each
chamber 12 is connected to the distributor 40 via the capillary
tube 50.
[0025] The distributor 40 includes therein an orifice (not shown)
that reduces a flow of the refrigerant. In the case where the heat
exchanger 1 is used as an evaporator, the distributor 40 causes a
two-phase gas-liquid flow entering thereinto to be a spray flow
(uniform flow) by passing the refrigerant through the orifice,
thereby making the refrigerant into a state where uniform
distribution of the refrigerant is easy. The refrigerant made into
a spray flow is uniformly distributed to the respective capillary
tubes 50 and flows thereinto, and flows into the respective
chambers 12 through the capillary tubes 50.
[0026] Each capillary tube 50 adjusts the pressure loss therein
with its specifications (length, inner diameter), thereby adjusting
a distribution ratio to each chamber 12 of the header 10a. Here,
the specifications of all of the capillary tubes 50 are the same,
and thus the refrigerant is flowed into each chamber 12 in the same
amount.
[0027] In manufacturing the heat exchanger 1 configured as
described above, the flattened pipes 20, the fins 30, and the pair
of headers 10 are simultaneously joined by means of brazing in a
furnace in an assembled state, and then the distributor 40 and each
respective capillary tube 50 are connected to each other.
[0028] FIG. 4 is a diagram showing a refrigerant circuit of a
refrigeration cycle apparatus to which the heat exchanger in FIG. 1
is applied.
[0029] A refrigeration cycle apparatus 60 includes a compressor 61,
a condenser 62, an expansion valve 63 as a pressure reducing
device, and an evaporator 64. The heat exchanger 1 is used in at
least one of the condenser 62 and the evaporator 64. A gas
refrigerant discharged from the compressor 61 flows into the
condenser 62, exchanges heat with air passing through the condenser
62, to become a high-pressure liquid refrigerant, and flows out
therefrom. The high-pressure liquid refrigerant having flowed out
of the condenser 62 is reduced in pressure by the expansion valve
63 to become a low-pressure two-phase gas-liquid refrigerant, and
flows into the evaporator 64. The low-pressure two-phase gas-liquid
refrigerant having flowed into the evaporator 64 exchanges heat
with air passing through the evaporator 64, to become a
low-pressure gas refrigerant, and is sucked into the compressor 61
again.
[0030] Hereinafter, a flow of the refrigerant in the case where the
heat exchanger 1 is used as an evaporator will be described with
reference to FIGS. 1 to 4. In FIG. 1, a solid arrow indicates the
flow of the refrigerant in the case where the heat exchanger 1 is
used as an evaporator.
[0031] The flow of the two-phase gas-liquid refrigerant having
flowed out of the expansion valve 63 first enters into the
distributor 40 and is made into a spray flow.
[0032] The refrigerant made into a spray flow is uniformly
distributed to the respective capillary tubes 50 and flows
thereinto. The refrigerant having passed through the respective
capillary tubes 50 flows into the respective chambers 12 of the
header 10a.
[0033] Here, in the case with a configuration of the related art in
which no division plate is provided in a header, since the entire
interior of the header is a single space, a head difference due to
the gravity is great, and thus a drift is likely to occur. However,
in the present embodiment, the division plates 11 are provided to
divide the interior of the header 10a, and the refrigerant is
flowed into each chamber 12 at which the head difference is small.
Thus, the effect of the head difference on the refrigerant having
flowed into each chamber 12 is reduced, and the refrigerant in each
chamber 12 is uniformly distributed to each flattened pipe 20
connected to the chamber 12 and flows thereinto.
[0034] The refrigerant having flowed into each flattened pipe 20
flows through the through holes 20a of the flattened pipe 20 toward
the header 10b, joins each other in the header 10b, and flows out
of the heat exchanger 1 through an external connection pipe 14.
[0035] Hereinafter, a flow of the refrigerant in the case where the
heat exchanger 1 is used as a condenser will be described with
reference to FIGS. 1 and 4. In FIG. 1, a dotted arrow indicates the
flow of the refrigerant in the case where the heat exchanger 1 is
used as a condenser.
[0036] The flow of the gas refrigerant having flowed out of the
compressor 61 enters into the header 10b, is uniformly distributed
therein, and flows into each flattened pipe 20. When the
refrigerant is in a gas state, uniform distribution of the
refrigerant is easy. Thus, a refrigerant distributing device such
as a distributor is unnecessary, and a configuration is provided in
which the flow of the gas refrigerant having flowed out of the
compressor 61 is directly flowed into the header 10b.
[0037] Then, the refrigerant having flowed into each flattened pipe
20 flows through the through holes 20a of the flattened pipe 20
toward the header 10a and flows into each chamber 12 of the header
10a. The refrigerant having flowed into each chamber 12 flows into
the distributor 40 via each capillary tube 50, joins each other
therein, and flows out of the heat exchanger 1.
[0038] According to the embodiment described above, in the case
where the heat exchanger 1 is used as an evaporator, a two-phase
refrigerant flow having entered thereinto is uniformly distributed
by the distributor 40, and the uniformly distributed refrigerant is
flowed into each chamber 12 at which the head difference is
reduced. Thus, the effect of the head difference on the refrigerant
having flowed into each chamber 12 is reduced, thereby allowing the
refrigerant to be uniformly distributed and flowed into each
flattened pipe 20 to suppress a drift. Therefore, use of the
refrigerant distributing device including the distributor 40 and
the header 10a allows the capacity of the evaporator to be
maximized to increase the heat exchange efficiency of the heat
exchanger 1 as an evaporator.
[0039] The position of each division plate 11 may be determined in
consideration of the head difference that allows uniform
distribution. Provision of only a minimum necessary number of
division plates 11 allows cost reduction.
[0040] In addition, the refrigerant distributing device and the
heat exchanger according to the present invention are not limited
to the structure shown in FIG. 1, and various changes such as (1)
to (4) below may be made without departing from the scope of the
present invention.
[0041] (1) A drift suppression member for suppressing a
distribution drift may further be provided at a refrigerant inflow
portion of each chamber 12.
[0042] Any member that is able to suppress a distribution drift may
be used as the drift suppression member, and, for example, an
orifice 70 may be provided as shown in FIG. 5. The orifice 70 is
provided at a connection port, at each chamber 12, connected to the
capillary tube 50 and has a through hole 71 with a smaller inner
diameter than that of the capillary tube 50. The orifice 70 further
reduces the flow of the refrigerant having flowed thereinto from
the capillary tube 50, by means of the through hole 71, thereby
promoting making the refrigerant into a spray flow. The promotion
of making the refrigerant into a spray flow makes distribution of
the refrigerant to each flattened pipe 20 in the chamber 12 to be
more uniform, thereby allowing a distribution drift to be further
suppressed.
[0043] (2) The height (the length in a direction in which the
plurality of flattened pipes 20 are disposed in parallel) of each
chamber 12 may be determined in accordance with a wind speed
distribution at the heat exchanger 1.
[0044] The wind speed of air blown from a fan to the heat exchanger
1 is not necessarily uniform over the entire surface of the heat
exchanger 1, and a wind speed distribution exists therein. For
example, in the case of a multi-air-conditioning apparatus for a
building, since a fan is provided at an upper portion of the heat
exchanger 1, the wind speed is higher at the upper portion of the
heat exchanger 1 than at a lower portion thereof. In the case where
the heat exchanger 1 is used as an evaporator, the refrigerant
passing through a portion where the wind speed is high progresses
in gasification further than the refrigerant passing through a
portion where the wind speed is low, and is easily dried. Thus, in
the case where the amount of the refrigerant flowing into each
chamber 12 is the same, the refrigerant having passed through the
portion where the wind speed is high has higher quality than that
of the refrigerant having passed through the portion where the wind
speed is low, and the state of the refrigerant flowing into the
header 10b is varied.
[0045] When the state of the refrigerant is varied as described
above, the state of the refrigerant flowing out of the external
connection pipe 14 is not stable. Thus, for a portion of the header
10a to which the flattened pipes 20 located at the portion where
the wind speed is high are connected, the heights of the chambers
12 are decreased such that a heat-exchange region per chamber is
reduced in size, whereby the number of flattened pipes connected to
the chamber 12 is decreased. This will be specifically described
below with reference to FIG. 6.
[0046] FIG. 6 is a diagram illustrating the principle of
determining the height of each chamber in accordance with a wind
speed distribution and shows here a case where a wind speed at the
upper side is high and a wind speed at the lower side is low. As
shown in FIG. 6, the height of each chamber 12A at the upper side
at which the wind speed is high is made smaller than the height of
each chamber 12B at the lower side at which the wind speed is low,
so that the number of the flattened pipes connected to each chamber
12A is made smaller than the number of the flattened pipes
connected to each chamber 12B. Thus, a heat-exchange region A at
the chamber 12A side is smaller than a heat-exchange region B at
the chamber 12B side, and the heat transfer area is small, so to
speak. Therefore, the substantial heat exchange amount is
substantially the same in the heat-exchange region A and the
heat-exchange region B, and it is possible to make the refrigerant
state at an outlet to be uniform.
[0047] The case has been described in which the amount of the
refrigerant flowing into each chamber 12 is the same and the
refrigerant state at the outlet is made uniform by changing the
heights of the chambers 12. However, the following case may be
employed. Specifically, the height of each chamber 12 is made the
same, and the distribution amount of the refrigerant flowing into
each chamber 12 is changed. In this case, the distribution amount
of the refrigerant flowing into each chamber 12 may be determined
in accordance with a wind speed distribution, and the
specifications (length, inner diameter) of each capillary tube 50
may be determined such that the determined distribution amount is
achieved. Specifically, the capillary tubes 50 are selected such
that the distribution amount for each chamber 12 to which the
flattened pipes 20 located at the portion where the wind speed is
high are connected is large and the distribution amount for each
chamber 12 to which the flattened pipes 20 at the portion where the
wind speed is low are connected is small.
[0048] (3) In the present embodiment, the case has been described
in which the entire heat exchanger 1 has substantially an I shape.
However, the entire heat exchanger 1 may have substantially an L
shape, substantially a U shape, or substantially a rectangular
shape. Which shape the heat exchanger 1 has may be determined in
accordance with a mounting space, within a housing, for the heat
exchanger 1 in which the heat exchanger 1 is mounted. The heat
exchanger 1 may have a shape that maximizes use of the mounting
space to allow the heat exchanger 1 to be densely mounted.
[0049] (4) In the present embodiment, each heat-transfer pipe is a
flattened pipe, but may not necessarily be a flattened pipe and may
be a circular pipe.
* * * * *