U.S. patent application number 14/851299 was filed with the patent office on 2016-03-10 for condenser assembly for refrigerant.
This patent application is currently assigned to MAHLE INTERNATIONAL GMBH. The applicant listed for this patent is MAHLE INTERNATIONAL GMBH. Invention is credited to Guillaume DAVID, Uwe FOERSTER, Matthias JUNG, Andreas KEMLE, Ottokar KUNBERGER, Christoph WALTER.
Application Number | 20160069597 14/851299 |
Document ID | / |
Family ID | 50277227 |
Filed Date | 2016-03-10 |
United States Patent
Application |
20160069597 |
Kind Code |
A1 |
FOERSTER; Uwe ; et
al. |
March 10, 2016 |
CONDENSER ASSEMBLY FOR REFRIGERANT
Abstract
A condenser assembly including a plurality of heat-exchanger
pipes, which are arranged equidistant from each other having
corrugated fins arranged therebetween and lead into deflection
regions at both ends and have a free length used for heat exchange
and, in connection with the corrugated fins, form a frontal area
having a width corresponding to the free length of the
heat-exchanger pipes and a height, such that the frontal area
results from the product of width and height. The heat-exchanger
pipes are connected in parallel in groups and the individual groups
are connected in series. The heat-exchanger pipes of the individual
groups are arranged adjacent and each group has at least two
heat-exchanger pipes. The percentage share of the heat-exchanger
pipes of the first group results from 26.162 In
(S/dm2)-40.746.ltoreq.P.ltoreq.25.49 In (S/dm2)-27.842 for a
frontal area.
Inventors: |
FOERSTER; Uwe;
(Erdmannhausen, DE) ; DAVID; Guillaume;
(Rochester, MI) ; KEMLE; Andreas; (Tamm, DE)
; JUNG; Matthias; (Stuttgart, DE) ; WALTER;
Christoph; (Stuttgart, DE) ; KUNBERGER; Ottokar;
(Korntal-Muenchingen, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MAHLE INTERNATIONAL GMBH |
Stuttgart |
|
DE |
|
|
Assignee: |
MAHLE INTERNATIONAL GMBH
Stuttgart
DE
|
Family ID: |
50277227 |
Appl. No.: |
14/851299 |
Filed: |
September 11, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2014/054891 |
Mar 12, 2014 |
|
|
|
14851299 |
|
|
|
|
Current U.S.
Class: |
165/104.21 |
Current CPC
Class: |
F25B 40/02 20130101;
F25B 39/00 20130101; F28D 1/05375 20130101; F28D 2021/0084
20130101; F25B 39/04 20130101; F25B 2339/0441 20130101 |
International
Class: |
F25B 39/00 20060101
F25B039/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 12, 2013 |
DE |
10 2013 204 294.9 |
Claims
1. A condenser assembly comprising: a plurality of heat exchanger
tubes, which are arranged equidistant from each other having
corrugated fins arranged therebetween and lead into deflection
regions at both ends, the heat exchanger tubes having a free length
used for heat exchange; and a frontal area formed by the heat
exchanger tubes and the corrugated fins, the frontal area having a
width corresponding to the free length of the heat exchanger tubes
and a height so that the frontal area results from the product of
width and height, wherein the heat exchanger tubes are connected in
parallel in groups and the individual groups in series, wherein the
heat exchanger tubes of the individual groups are arranged adjacent
and each group comprises at least two heat exchanger tubes, and
wherein a percentage share of the heat exchanger tubes of the first
group results from 26.162 In
(S/dm.sup.2)-40.746.ltoreq.P.ltoreq.25.49 In (S/dm.sup.2)-27.842
for the frontal area having a width to height ratio in the range
from 0.5 to 1.0, the frontal area being in the range from 10 to 30
dm.sup.2, and a specification of the area of the frontal area in
dm.sup.2.
2. The condenser assembly according to claim 1, wherein at least
two groups are provided as flow paths in the supercooling
region.
3. The condenser assembly according to claim 1, wherein the
percentage share of the heat exchanger tubes of the first group
results from: 26.162 In (S/dm.sup.2)-35.746.ltoreq.P.ltoreq.25.49
In (S/dm.sup.2)-32.842.
4. The condenser assembly according to claim 1, wherein at an Lh to
Lv ratio of 0.5, the percentage share results from: 26.162 In
(S/dm.sup.2)-40.746.ltoreq.P.ltoreq.26.162 In (S/dm.sup.2)-30 and
at an Lh to Lv ratio of 1.0, the percentage share (P) results from:
25.49 In (S/dm.sup.2)-35 .ltoreq.P.ltoreq.25.49 In
(S/dm.sup.2)-27.842.
5. The condenser assembly according to claim 1, wherein the
condenser assembly has at least four regions connected in series,
and wherein the first region of the regions connected in series
accounts for a percentage share of the entire frontal area.
6. The condenser assembly according to claim 5, wherein the
percentage share of the regions connected in series decreases in
the normal flow direction of the refrigerant from the first region
to the second region.
7. The condenser assembly according to claim 6, wherein the
percentage share of the regions connected in series decreases in a
normal flow direction of the refrigerant from the second region to
the third region.
8. The condenser assembly according to claim 1, wherein the
percentage share of the regions connected in series decreases in
the normal flow direction of the refrigerant at a beginning of the
series and is constant at the end the series.
9. The condenser assembly according to claim 1, wherein the
percentage share of the first region of six regions, connected in
series in the normal flow direction of the refrigerant, is greater
than the percentage share of the second region, and the percentage
share of the third region in each case is the same as the
percentage share of the fourth region of the fifth region and of
the sixth region.
10. The condenser assembly according to claim 1, wherein in the
case of a square design of the frontal area, a percentage share of
the first region of six regions connected in series in a normal
flow direction of the refrigerant is twice as large as a percentage
share of the second region, and a percentage share of the third
region in each case is the same as a percentage share of the fourth
region of the fifth region and of the sixth region, wherein a sum
of the percentage shares of the third, fourth, fifth, and sixth
regions is the same as the percentage share of the second region,
and wherein the percentage share of the first region is the same as
a sum of the percentage shares of the rest of regions.
11. The condenser assembly according to claim 1, wherein the
deflection regions are disposed within headers, wherein the
refrigerant-receiving volume of the headers in the normal flow
direction of the refrigerant in a first deflection region between
the first region and the second region is greater than in a second
deflection region between the second region and the third region,
and wherein a collecting tank is disposed after the third region.
Description
[0001] This nonprovisional application is a continuation of
International Application No. PCT/EP2014/054891, which was filed on
Mar. 12, 2014, and which claims priority to German Patent
Application No. 10 2013 204 294.9, which was filed in Germany on
Mar. 12, 2013, and which are both herein incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a condenser assembly.
[0004] 2. Description of the Background Art
[0005] Not insignificant drops in performance in the area of the
refrigerant circuit result when refrigerant R1234yf is used instead
of the current refrigerant R134a in vehicle climate control
systems. In order to increase the refrigerant circuit performance,
for example, greater supercooling of the already liquefied
refrigerant is possible; i.e., the refrigerant is cooled in a
supercooling region to a temperature below the condensation
temperature of the refrigerant.
[0006] A condenser assembly of a vehicle climate control system for
refrigerants with this type of approach for increasing performance
is known, for example, from DE 10 2010 039 511 A1, which
corresponds to US 2013/0219932, and which is incorporated herein by
reference. This known condenser assembly provides a collecting tank
on a first longitudinal side of the refrigerant condenser assembly,
two headers, heat exchanger tubes in a superheat region for cooling
the vaporous refrigerant, a condensation region for condensing the
refrigerant, and a supercooling region wherein the supercooling
region is formed with three cooling sections, whereby at least two
heat exchanger tubes as a first supercooling parallel section are
supplied in parallel with the refrigerant in a fluid-conducting
manner, the refrigerant flowing out of the first supercooling
parallel section flows into a first supercooling intermediate flow
channel. This first supercooling intermediate flow channel opens
into at least two heat exchanger tubes as the second supercooling
parallel section. This second parallel supercooling section opens
into a second supercooling intermediate flow channel. The second
supercooling intermediate flow channel opens into at least two heat
exchanger tubes as the third parallel supercooling section, whereby
an outlet opening is disposed on a second longitudinal side of the
refrigerant condenser assembly.
[0007] In conventional condenser assemblies, however, an enlarged
supercooling section, formed by three regions connected in series,
at a comparable overall size of the condenser assembly, results in
a reduced condensation region, whereby the high pressure in the
refrigerant circuit increases. Such a condenser assembly therefore
still leaves much to be desired in regard to cooling performance
and efficiency.
SUMMARY OF THE INVENTION
[0008] It is therefore the object of the present invention to
provide a condenser assembly that has a better cooling performance
and a higher efficiency.
[0009] By means of a condenser assembly design in which the
percentage share of the heat exchanger tubes of the first group
results from
26.162 In (S/dm.sup.2)-40.746.ltoreq.P.ltoreq.25.49 In
(S/dm.sup.2)-27.842
[0010] for a frontal area (S) having a width to height ratio in the
range from 0.5 to 1.0, a frontal area in the range from 10 to 30
dm.sup.2, and a specification of the area of the frontal area in
dm.sup.2 (in the argument of the natural logarithm), an optimized
cooling performance results compared with condenser assemblies that
have a greater or lower percentage share of heat exchanger tubes of
the first assembly in terms of the aforementioned relationship.
[0011] In particular, the percentage share of the heat exchanger
tubes of the first group results from
26.162 In (S/dm.sup.2)-35.746.ltoreq.P.ltoreq.25.49 In
(S/dm.sup.2)-32.842
[0012] Such a design can be used in particular for condensers with
a supercooling region, which has three cooling sections with at
least two tubes in each cooling section.
[0013] Both R134 and R1234yf can be used as refrigerants but other
refrigerants as well that have properties approximately comparable
to R134 or R1234yf.
[0014] At an Lh to Lv ratio of 0.5, the percentage share results
preferably from:
26.162 In (S/dm.sup.2)-40.746.ltoreq.P.ltoreq.28.162 In
(S/dm.sup.2)-30
[0015] and at an Lh to Lv ratio of 1.0 from:
25.49 In (S/dm.sup.2)-35.ltoreq.P.ltoreq.25.49 in
(S/dm.sup.2)-27.842.
[0016] The condenser assembly can have at least four regions
connected in series, whereby the first region of the regions
connected in series accounts for the percentage share of an entire
frontal area. In this case, the percentage share of the regions
connected in series can decrease in the normal flow direction of
the refrigerant from the first region to the second region.
Further, the percentage share of the regions connected in series
can decrease in the normal flow direction of the refrigerant from
the second region to the third region.
[0017] The percentage share of the regions connected in series
decreases in the normal flow direction of the refrigerant at the
beginning of the series and is constant at the end of the
series.
[0018] In an exemplary condenser assembly, the percentage share of
the first region of six regions, connected in series in the normal
flow direction of the refrigerant, is greater than the percentage
share of the second region, and the percentage share of the third
region in each case is preferably the same as the percentage share
of the fourth region, the fifth region, and the sixth region.
[0019] In the case of a square design of the frontal area, the
percentage share of the first region of six regions, connected in
series in the normal flow direction of the refrigerant, is
preferably twice as large as the percentage share of the second
region, and the percentage share of the third region in each case
is preferably the same as the percentage share of the fourth
region, the fifth region, and the sixth regions, whereby the sum of
the percentage shares of the third, fourth, fifth, and sixth region
is preferably the same as the percentage share of the second
region, and the percentage share of the first region is preferably
the same as the sum of the percentage shares of the rest of the
regions.
[0020] The deflection regions can be disposed within headers,
whereby the refrigerant-receiving volume of the headers in the
normal flow direction of the refrigerant in a first deflection
region between the first region and the second region is preferably
greater than in a second deflection region between the second
region and the third region, whereby a collecting tank is disposed
preferably after the third region.
[0021] The invention is especially suitable for condenser
assemblies with a triple-flow supercooling region with in each case
at least two heat exchanger tubes, but can also be used for other
condenser assemblies, for example, with a single-flow supercooling
region and triple-flow condensation region.
[0022] Further scope of applicability of the present invention will
become apparent from the detailed description given hereinafter.
However, it should be understood that the detailed description and
specific examples, while indicating preferred embodiments of the
invention, are given by way of illustration only, since various
changes and modifications within the spirit and scope of the
invention will become apparent to those skilled in the art from
this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention will become more fully understood from
the detailed description given hereinbelow and the accompanying
drawings which are given by way of illustration only, and thus, are
not limitive of the present invention, and wherein:
[0024] FIG. 1 shows a schematic illustration of a condenser
assembly with three cooling sections according to the first
exemplary embodiment;
[0025] FIG. 2 shows a partial schematic illustration of a heat
exchanger surface of the condenser assembly of FIG. 1;
[0026] FIG. 3 shows a schematic illustration of a condenser
assembly with three cooling sections according to the second
exemplary embodiment; and
[0027] FIG. 4 shows a diagram of the percentage share of the heat
exchanger tubes of a first region versus the heat exchanging
frontal area.
DETAILED DESCRIPTION
[0028] A condenser assembly 1, which is part of a vehicle climate
control system (not shown in greater detail) with an evaporator
disposed in a refrigerant circuit and a compressor, has a first and
second longitudinal side Lv or Lh, respectively, positioned
laterally. Condenser assembly 1 is typically installed in a motor
vehicle such that both longitudinal sides Lv, Lh extend
substantially in the vertical direction (y-direction) and are
arranged spaced apart in the z-direction. The depth of condenser
assembly 1 extends in the x-direction, whereby the x-direction
corresponds to the air flow direction through condenser assembly 1,
i.e., it runs opposite to the normal direction of travel of the
vehicle. Corresponding specifications of directions will be used
hereinafter to describe condenser assembly 1.
[0029] On first longitudinal side Lv at the top on condenser
assembly 1, an inlet opening 2 is disposed, through which the
refrigerant, in the present case R1234yf, circulated in the
refrigerant circuit, enters condenser assembly 1. Header 3,
continuous in the present case, is disposed on each longitudinal
side Lv, Lh of condenser assembly 1. Headers 3 are connected to one
another in a manner known per se via heat exchanger tubes 4, formed
by flat tubes. Baffles are disposed in headers 3 in order to
predefine the flow path (indicated schematically by arrows in the
drawing) of the refrigerant through heat exchanger tubes 4 and to
separate individual deflection regions from one another. Corrugated
fins 5, which have a thermal and mechanical connection with heat
exchanger tubes 4 and increase the heat exchange surface area of
heat exchanger tubes 4 and thereby of condenser assembly 1, are
disposed in a known manner between heat exchanger tubes 4.
[0030] The heat exchanging region of condenser assembly 1 in the
present case is flown through in a z-shaped manner in the much
larger top region, whereby the height and thereby the number of
parallel-arranged heat exchanger tubes 4, through which refrigerant
flows in one direction, decrease greatly downwards before the
refrigerant at the bottom end of this top region, obliquely
opposite to inlet opening 2, flows into a collecting tank 6, which
is constructed in a conventional manner parallel to a header 3
disposed on second longitudinal side Lh and in which a dryer and
filter (not shown) are disposed. In this case, reference is made to
the top group of heat exchanger tubes 4, with parallel flow in one
direction, of this top region as the first flow path (first region
A), to the middle group of heat exchanger tubes 4, with parallel
flow opposite to the top group, of this top region as the second
flow path (second region B), and to the bottom group of heat
exchanger tubes 4, with parallel flow opposite to the middle group,
of this top region as the third flow path (third region C). These
individual regions A-C are each connected in series via said
deflection regions. Because of the function, namely, that in the
corresponding top region of condenser assembly 1 the overheated
gaseous refrigerant is cooled to a saturation temperature, the
first region A is also called the superheat region. The second and
third region B and C together are called the condensation region,
because in this region the refrigerant cooled to the saturation
temperature is condensed and then enters collecting tank 6 as a
fluid.
[0031] A supercooling region 7 as a further part of condenser
assembly 1, to which refrigerant liquefied in the condensation
region is supplied, is provided as a smaller bottom region
downstream of collecting tank 6. The flow in said supercooling
region 7 in the present case is also z-shaped, proceeding from the
bottom end region of collecting tank 6. In keeping with DE 10 2010
039 511 A1, supercooling region 7 is formed by three cooling
sections, in each case by two heat exchanger tubes, running
parallel to one another, and deflection regions disposed
therebetween in header 3, whereby at the end the refrigerant enters
an outlet opening 8 via header 3 disposed on first longitudinal
side Lv. According to the designation of the regions of the larger
top region A-C, reference is made to these heat exchanger tubes in
the sequence of the normal throughflow with the refrigerant as
regions D, E, and F. The deflection of the refrigerant in
supercooling region 7 between the individual cooling sections
occurs in the present case in headers 3 by baffles, in keeping with
the deflection in the larger top region; it can also occur in any
other manner, however; i.e., headers 3 can also end, for example,
above supercooling region 7 and the deflection can occur by means
of separately formed deflection regions.
[0032] Headers 3, heat exchanger tubes 2, corrugated fins 5, and
optionally the deflection regions usually are formed of metal, in
the present case of aluminum. The individual components in the
present case are connected together by material bonding as solder
connections but a different fabrication with a suitable structure
is also conceivable.
[0033] The design of the flow paths for an optimal cooling
performance of condenser assembly 1 will be elaborated upon
hereafter. In this regard, reference is made to the area which lies
in the yz-plane and is defined as frontal area S below in the z
direction by the (free) length Lh of heat exchanger tubes 4 between
headers 3 and in the y-direction by the distance Lv between the top
and bottom edge of the respective topmost or lowest corrugated fin;
i.e., the frontal area S results from Lh.times.Lv. Reference is
made to Lh below also as the width and to Lv also as the height.
The (free) length Lh of the individual heat exchanger tubes 4 in
the region of frontal area S is the same in each case in the
described embodiment. It can also be different, however, in
alternative embodiments. Further, all heat exchanger tubes 4 with
free flow cross sections, corresponding to one another and constant
over the length of heat exchanger tubes 4, and all heat exchanger
tubes 4 are arranged equidistant from each other over the height of
condenser assembly 1.
[0034] The entire flow path of the refrigerant within heat
exchanging region A-C and accordingly of supercooling region D-E
results based on the deflection in each case approximately as
3.times.Lh, whereby in each case a plurality of parallel heat
exchanger tubes 4 are provided within the individual regions A-F,
and the number of parallel-connected heat exchanger tubes 4 in
regions A, B, and C decreases in the direction of the flow path.
The number of parallel-connected heat exchanger tubes 4 in regions
D-E is constant in the present case. It can also correspond to the
number of parallel-connected heat exchanger tubes in region C. In
the present case, the number of parallel-connected heat exchanger
tubes in regions C-F is two in each case.
[0035] Insofar as they are described above, the two exemplary
embodiments in FIGS. 1 and 3 correspond to one another.
[0036] The ratio of the number of heat exchanger tubes (and thereby
the area proportion in regard to frontal area S) of first region A,
designated below as nA, to the number of heat exchanger tubes nB of
second region B is essential for optimizing the cooling performance
of condenser assembly 1. The effect of third region C with nC heat
exchanger tubes is of minor importance for the performance of
condenser assembly 1. The number of heat exchanger tubes in the
fourth to sixth region nD, nE, and nF is also of minor
importance.
[0037] The percentage share of the heat exchange area of first
region A in relation to the entire heat exchange area, i.e., to the
entire frontal area S, is designated by P hereafter.
[0038] At an Lh to Lv ratio in the range from 0.5 to 1.0 and a
specification of the area in dm.sup.2, at a relation of:
26.162 In (S/dm.sup.2)-35.746.ltoreq.P.ltoreq.25.49 In
(S/dm.sup.2)-32.842,
[0039] this results in the share of heat exchanger tubes 4,
associated with the first region, in regard to the total number of
heat exchanger tubes 4 as a percentage, which leads to an optimal
performance of a climate control system with a condenser assembly 1
designed according to the invention. The bottom limit in this case
for an Lh to Lv ratio is 0.5, and the top limit for an Lh to Lv
ratio is 1.0.
[0040] In other words, for example, an advantageous share of heat
exchanger tubes 4 for a heat exchanging frontal area S of 25
dm.sup.2 in the first region of about 54% results. Thereby, a
corresponding ratio P (in %) of the number of heat exchanger tubes
4 of first region A to the total number of heat exchanger tubes 4
of:
P=nA/[100.times.(nA+nB+nC+nD+nE+nF)]
[0041] also results automatically with a "square" design of the
frontal area. Accordingly, a condenser assembly 1 with a ratio of
Lh/Lv of 1.0 is shown in FIG. 1 as the first exemplary
embodiment.
[0042] At an Lh to Lv ratio of 0.5, therefore in the case of a
width that is twice as large as the height of the frontal area, an
advantageous share (of heat exchanger tubes 4 in first region A) of
about 43% results, as shown schematically in FIG. 3 as the second
exemplary embodiment. It should be mentioned as a precaution that
the basic structure of the heat exchanging area with heat exchanger
tubes 4 and corrugated fins 5 does not differ. The sole difference
is the arrangement of the baffles (not shown in greater detail) in
headers 3, which result in a different throughflow direction in the
subsections of the heat exchanging area; that is, the first change
in direction is slightly farther above in relation to the total
height in condenser assembly 1 according to the second exemplary
embodiment.
[0043] Thus, in the case of a square design of frontal area S and a
height of the same of about 25 dm.sup.2, as provided according to
the first exemplary embodiment, about half of all heat exchanger
tubes 4 are associated with first region A. If frontal area S is
enlarged, however, thus the share of heat exchanger tubes 4 to be
associated advantageously with first region A increases, and if the
size of frontal area S is decreased, thus the share declines to
about 30% in the case of an frontal area S of, for example, 10
dm.sup.2.
[0044] In the case of a rectangular design of frontal area S with
an Lh to Lv ratio of 0.5, as provided according to the second
exemplary embodiment, the percentage share of first region A is
about 10% lower.
[0045] With consideration of a safety margin of 5% upwards and
downwards, a relation of
26.162 In (S/dm.sup.2)-40.746.ltoreq.P.ltoreq.25.49 In
(S/dm.sup.2)-27.842
for the share of heat exchanger tubes 4, associated with the first
region, results in relation to the total number of heat exchanger
tubes 4 as a percent, which leads to a good performance of a
climate control system with a condenser assembly 1 made according
to the invention.
[0046] The above relation holds in particular for frontal areas S
in the range from 10 to 30 dm.sup.2, particularly in the range from
15 to 25 dm.sup.2, whereby the plurality of condensers used in the
automotive sector have a suitably large frontal area S.
[0047] According to the first and second exemplary embodiment,
second region B is made approximately as large as the third to
sixth regions C-F together.
[0048] A suitable relation for the percentage design of first
region A in regard to the entire heat exchanging frontal area S can
also be used if the supercooling region is made not as a
triple-flow region as described above, but as a double-flow or
multiflow region, whereby the number of flat tubes in the
supercooling region is at least 6 to 16 overall. Therefore, the
above equation for P can also be used as equal to zero for nE
and/or nF, provided the sum of the heat exchanger tubes in the
supercooling region is within the range of 6 to 16.
[0049] Although described as continuous tubes with baffles
according to the present exemplary embodiment and in the drawing,
headers 3 can also be formed by individual, separately formed
deflection regions; in particular, the flow cross sectional area
and/or volume thereof can decrease in the flow direction of the
refrigerant, as disclosed in DE 10 2011 007 216 A1, which is
incorporated herein by reference. A corresponding flow cross
section area decrease is advantageous particularly between the
first deflection region (area between region A and region B) and
the second deflection region (area between region B and region C),
but it can be provided advantageously in addition between the
following regions.
[0050] The invention being thus described, it will be obvious that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be obvious to one skilled in
the art are to be included within the scope of the following
claims.
* * * * *