U.S. patent application number 16/473603 was filed with the patent office on 2019-11-07 for heat exchanger for exchanging heat of fluids having different temperatures.
The applicant listed for this patent is PTT Global Chemical Public Company Limited, PTT Public Company Limited. Invention is credited to Rungroj Chuvaree, Supawish Klannark, Nichaporn Sirimungkalakul, Kawisra Sompech, Thana Sornchamni, Wannawijit Srithammarat, Nattapong Tarapoom, Treerat Vacharanukrauh.
Application Number | 20190339018 16/473603 |
Document ID | / |
Family ID | 62710367 |
Filed Date | 2019-11-07 |
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United States Patent
Application |
20190339018 |
Kind Code |
A1 |
Tarapoom; Nattapong ; et
al. |
November 7, 2019 |
Heat exchanger for exchanging heat of fluids having different
temperatures
Abstract
A heat exchanger for exchanging heat of fluids having different
temperatures, comprising: at least one smooth heat exchanging
plate; at least one high temperature heat exchanging plate; and at
least one low temperature heat exchanging plate stacked in an
alternating sequence, wherein an inlet of high temperature fluid
and an outlet of high temperature fluid are disposed in order to
pass a high temperature fluid through each said high temperature
heat exchanging plate, and an inlet of low temperature fluid and an
outlet of low temperature fluid are disposed in order to pass a low
temperature fluid through each said low temperature heat exchanging
plate, wherein said high temperature heat exchanging plate and said
low temperature the heat exchanging plate comprising a high
temperature channel and a low temperature channel, wherein said
channels have a length extending in a flow direction of said fluids
and a side wall of each said channel has a symmetric wavy pattern
with the center line of said channel.
Inventors: |
Tarapoom; Nattapong;
(Bangkok, TH) ; Vacharanukrauh; Treerat; (Bangkok,
TH) ; Sompech; Kawisra; (Bangkok, TH) ;
Srithammarat; Wannawijit; (Bangkok, TH) ; Klannark;
Supawish; (Bangkok, TH) ; Sirimungkalakul;
Nichaporn; (Bangkok, TH) ; Sornchamni; Thana;
(Bangkok, TH) ; Chuvaree; Rungroj; (Bangkok,
TH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PTT Global Chemical Public Company Limited
PTT Public Company Limited |
Bangkok
Bangkok |
|
TH
TH |
|
|
Family ID: |
62710367 |
Appl. No.: |
16/473603 |
Filed: |
December 21, 2017 |
PCT Filed: |
December 21, 2017 |
PCT NO: |
PCT/TH2017/000089 |
371 Date: |
June 25, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 2260/02 20130101;
F28F 3/025 20130101; F28F 3/046 20130101; F28D 9/0037 20130101;
F28D 2021/0022 20130101; F28D 9/0062 20130101; F28D 9/0068
20130101 |
International
Class: |
F28D 9/00 20060101
F28D009/00; F28F 3/02 20060101 F28F003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 26, 2016 |
TH |
1601007738 |
Claims
1. A heat exchanger for exchanging heat of fluids having different
temperatures comprising: at least one flat heat exchanging plate
(12); at least one high temperature heat exchanging plate (14); and
at least one low temperature heat exchanging plate (16) stacked in
an alternating sequence, wherein an inlet of high temperature fluid
(18a) and an outlet of high temperature fluid (20a) are disposed in
order to pass a high temperature fluid through each said high
temperature heat exchanging plate (14), and an inlet of low
temperature fluid (18b) and an outlet of low temperature fluid
(20b) are disposed in order to pass a low temperature fluid through
each said low temperature heat exchanging plate (16); characterized
in that said high temperature heat exchanging plate (14) comprising
a high temperature channel (15) and said low temperature heat
exchanging plate (16) comprising a low temperature channel (17),
wherein said channels have a length extending in a flow direction
of said fluids and a side wall of each said channel has a symmetric
wavy pattern with a center line of said channel as a symmetric
axis.
2. The heat exchanger according to claim 1, wherein the high
temperature channel (15) and the low temperature channel (17) have
an average width (y) in a range of 100 to 5,000 .mu.m and a curve
length (x) and a curve radius (r) according to x.ltoreq.2r, wherein
x is in a range of 100 to 100,000 .mu.m.
3. The heat exchanger according to claim 1, wherein the high
temperature channel (15) and the low temperature channel (17) have
an average width (y) in the range of 100 to 3,000 .mu.m, a curve
length (x) in the range of 1,000 to 3,000 .mu.m, and a curve radius
(r) in the range of 2,000 to 5,000 .mu.m.
4. The heat exchanger according to claim 1, wherein the high
temperature channel (15) and the low temperature channel (17) have
a depth in a range of 10 to 2,000 .mu.m according to a plane
defined by the top of each high temperature heat exchanging plate
(14) and each low temperature heat exchanging plate (16).
5. The heat exchanger according to claim 4, wherein the high
temperature channel (15) and the low temperature channel (17) have
the depth in a range of 500 to 1,500 .mu.m according to the plane
defined by the top of each high temperature heat exchanging plate
(14) and each low temperature heat exchanging plate (16).
6. The heat exchanger according to claim 4, wherein the high
temperature heat exchanging plate (14) and the low temperature heat
exchanging plate (16) are arranged in a direction such that the
high temperature channel (15) and the low temperature channel (17)
are oriented in alternate configuration.
7. The heat exchanger according to claim 1, wherein the flat heat
exchanging plate (12), the high temperature heat exchanging plate
(14), and the low temperature heat exchanging plate (16) have a
thickness in a range of 10 to 10,000 .mu.m.
8. The heat exchanger according to claim 7, wherein the flat heat
exchanging plate (12), the high temperature heat exchanging plate
(14), and the low temperature heat exchanging plate (16) have the
thickness in the range of 100 to 2,000 .mu.m.
9. The heat exchanger according to claim 1, wherein the inlet of
high temperature fluid (18a) and the inlet of low temperature fluid
(18b) are disposed in the opposite side of the heat exchanger in
order to form counter-flow of fluids having different
temperatures.
10. The heat exchanger according to claim 1, wherein said fluids
have a temperature difference at least 1.degree. C.
11. The heat exchanger according to claim 10, wherein said fluids
have the temperature difference at least 10.degree. C.
Description
TECHNICAL FIELD
[0001] Chemical engineering relates to a heat exchanger for
exchanging heat of fluids having different temperatures.
BACKGROUND OF THE INVENTION
[0002] Until present, there have been reports on the development of
microchannel heat exchanger. When compared to the normal size
channels, the microchannels provide a higher heat transfer
performance than normal heat exchanger, such as a shell and a tube
heat exchanger and a plate and a frame heat exchanger. This is
because the flow in microchannels can transfer heat from a channel
wall into fluid faster, fluids in each channel have similar flow
cross section temperatures, a heat transfer surface area is higher
than normal channel at the same volume, and a pressure drop in the
channel is relatively low. However, the microchannels have some
disadvantages that lead to limitation for application. For example,
it is easily to be clogged because the channel is narrow.
Especially, when being used for heat exchanging of fluids having
highly different pressure, the permanent deforming can be
happened.
[0003] It is known that the character of the channel of the heat
exchanger is important to the heat transfer performance and the
overall strength of the heat exchanger. In addition, the character
of the channel is a parameter to indicate the possibility in
fabrication and the arrangement of the channel together. Therefore,
there have been attempts continuously to develop the character of
the channel in order to increase the performance of the heat
exchanger and overcome the limitations previously said.
[0004] US20040031592 disclosed the heat exchanger comprising
microchannel for the heat exchanging of three or more fluid
streams, wherein the wall of said channel was flat with fins
disposed in order to increase the heat changing surface area.
However, the installation of said fins increased a fouling rate
inside the heat exchanger. Therefore, this reduced the heat
transfer performance and increased the pressure drop of the heat
exchanger. Moreover, said design might have a problem when using
with high pressure fluid, leading to a limitation.
[0005] U.S. Pat. No. 4,516,632 disclosed the microchannel heat
exchanger comprising the slotted heat exchanging sheets and
unslotted heat exchanger sheets stacked in an alternating sequence,
wherein the slotted heat exchanging sheet was placed in 90 degree
with respect to one another in an alternating sequence in order to
form a cross-flow configuration of fluids having different
temperatures. Nevertheless, said flow configuration did not give a
high heat exchanging performance.
[0006] EP1875959 disclosed the forming process of an emulsion with
the installation of the heat exchanger comprising the microchannel
heat exchanging plate stacked in an alternating sequence, wherein
said channel was designed like a snake shape. This made two flowing
patterns in said channel: a counter-current and a co-current.
However, said channel design leads to easily clogging of the
contaminants and was more difficult to clean comparing to the one
flow direction path from one side to another side.
[0007] U.S. Pat. No. 8,858,159 disclosed a gas turbine comprising
cooling channels for the low temperature air to flow pass and
reduce heat of blades in the gas turbine, wherein said cooling
channels were equipped with curved in and out ribs and the
pedestals between each pair of ribs in order to increase the heat
transfer performance. However, the character of said pedestals
between each pair of ribs might increase the pressure drop of the
heat exchanger which was the limitation when applying to the heat
transfer between fluids with highly different pressure or fluids
with high viscosity.
[0008] US20100314088 disclosed the heat exchanger comprising plates
consisting of micrcochannels stacked in an alternating sequence.
Said plates were designed to be curved and said microchannels were
set into non-symmetric wavy form making parallel channel along the
flow direction of fluids. The total length of direct portion and
curve portion was set to be constant. However, said patent did not
disclose the suitable parameters of said wavy channel such as width
size, curve radius, etc.
[0009] From all above, this invention aims to provide the heat
exchanger for exchanging heat of fluids having different
temperatures, especially to increase the heat transfer performance
of said fluids and decrease problems related to the heat exchanger
for exchanging heat of fluids having highly different
pressures.
SUMMARY OF INVENTION
[0010] This invention aims to provide the heat exchanger for
exchanging heat of fluids having different temperatures, especially
to increase the heat exchanging performance of said fluids having
different temperatures and decrease problems related to the heat
exchanger for exchanging heat of fluids having highly different
pressures.
[0011] In one aspect of the invention, this invention discloses the
heat exchanger for exchanging heat of fluids having different
temperatures, comprising: at least one flat heat exchanging plate;
at least one high temperature heat exchanging plate; and at least
one low temperature heat exchanging plate stacked in an alternating
sequence, wherein an inlet of high temperature fluid and an outlet
of high temperature fluid are disposed in order to pass the high
temperature fluid through each said high temperature heat
exchanging plate, and an inlet of an low temperature fluid and an
outlet of low temperature fluid are disposed in order to pass the
low temperature fluid through each said low temperature heat
exchanging plate, wherein said high temperature heat exchanging
plate and said low temperature heat exchanging plate comprising the
high temperature channel and the low temperature channel, wherein
said channels have a length extending in a flow direction of said
fluids and a side wall of each said channel has a symmetric wavy
pattern with, a center line of each said channel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows one aspect of the heat exchanger according to
the present invention.
[0013] FIG. 2 shows one aspect of the arrangement of the heat
exchanging plate of the heat exchanger according to the present
invention.
[0014] FIG. 3 shows one aspect of each high temperature channel and
each high temperature channel of the heat exchanger according to
the present invention.
[0015] FIG. 4 shows one aspect of the high temperature heat
exchanging plate and the low temperature heat exchanging plate of
the heat exchanger according to the present invention from a)
isometric, b) top, and c) front views.
[0016] FIG. 5 shows one aspect of the high temperature heat
exchanging plate and the low temperature heat exchanging plate of
the comparative heat exchanger comprising the non-symmetric wavy
channel from a) isometric, b) top, and c) front views.
[0017] FIG. 6 shows one aspect of the high temperature heat
exchanging plate and the low temperature heat exchanging plate of
the comparative heat exchanger comprising the straight channel from
a) isometric, b) top, and c) front views.
[0018] FIG. 7 shows the amount of transferred heat to the flow
volume of the heat exchanger according to the present invention and
the heat exchanger according to the prior art.
DESCRIPTION OF THE INVENTION
[0019] The present invention relates to the heat exchanger for
exchanging heat of fluids having different temperatures as
described according to the following embodiments.
[0020] Any aspect used herein refers including the application to
other aspects of this invention unless stated otherwise.
[0021] Technical terms or scientific terms used herein have
definitions as understood by an ordinary person skilled in the art
unless stated otherwise.
[0022] Any tools, equipment, methods, or chemicals mentioned herein
mean tools, equipment, methods, or chemicals commonly operated or
use by those person skilled in the art unless explicated that they
are tools, equipment, methods, or chemicals specific only in this
invention.
[0023] Use of singular noun or singular pronoun with "comprising"
in claims or specification refers to "one" and also "one or more",
"at least one", and "one or more than one".
[0024] The following details describe in the specification of the
invention, and are not intend to limit the scope of the invention
in any way. This invention discloses the heat exchanger for
exchanging heat of fluids having different temperatures,
comprising: at least one flat heat exchanging plate; at least one
high temperature heat exchanging plate; and at least one low
temperature heat exchanging plate stacked in an alternating
sequence, wherein an inlet of the high temperature fluid and an
outlet of the high temperature fluid are disposed in order to pass
the high temperature fluids through each said high temperature heat
exchanging plate, and an inlet of low temperature fluid and an
outlet of low temperature fluid are disposed in order to pass a low
temperature fluid through each said low temperature heat exchanging
plate, wherein said high temperature heat exchanging plate and low
temperature heat exchanging plate comprising a high temperature
channel and a low temperature channel, wherein said channels have a
length extending in a flow direction of said fluids and a side wall
of each said channel has symmetric wavy curve pattern with a center
line of each said channel as a symmetric axis.
[0025] FIGS. 1 and 2 show one aspect of the the heat exchanger
according to the present invention. In this aspect, the heat
exchanger comprising at least one flat heat exchanging plate 12; at
least one high temperature heat exchanging plate 14; and at least
one low temperature heat exchanging plate 16 stacked in an
alternating sequence, wherein an inlet of high temperature fluid
18a and an outlet of high temperature fluid 20a are disposed in
order to pass a high temperature fluid through each said high
temperature heat exchanging plate 14, and an inlet of low
temperature fluid 18b and an outlet of low temperature fluid 20b
are disposed in order to pass the-low temperature fluid through
each said low temperature heat exchanging plate 16. In each said
plate, the said inlet and outlet parts assembly can be separated
from the heat exchanger.
[0026] The said high temperature heat exchanging plate 14
comprising the high temperature channel 15 and said low temperature
heat exchanging plate 16 comprising the low temperature channel 17,
wherein said channels have a length extending the flow direction of
said fluid and the side wall of each said channel has a symmetric
wavy curve pattern with the center line of each said channel as a
symmetric axis.
[0027] In one embodiment, the high temperature channel 15 and the
low temperature channel 17 have an average width (y) in a range of
100 to 5,000 .mu.m and the curve length (x) and the curve radius
(r) according to this equation:
x.ltoreq.2r,
[0028] wherein x is in a range of 100 to 100,000 .mu.m.
[0029] Preferably, said channel have the average width in the range
of 100 to 3,000 .mu.m, the curve length in the range of 1,000 to
3,000 .mu.m, and the curve radius in the range of 2,000 to 5,000
.mu.m.
[0030] In one embodiment, the high temperature channel 15 and the
low temperature channel 17 have the depth in the range of about 10
to 2,000 .mu.m when comparing to the plane set by the top of each
high temperature heat exchanging plate 14 and each low temperature
heat exchanging plate 16. Preferably, the high temperature heat
exchanging plate 14 and the low temperature heat exchanging plate
16 are arranged in order to place the high temperature channel 15
and the low temperature channel 17 oriented in alternate
configuration as shown in FIG. 2.
[0031] In one embodiment, the flat heat exchanging plate 12, the
high temperature heat exchanging plate 14, and the low temperature
heat exchanging plate 16 have a thickness in a range of about 10 to
10,000 .mu.m, preferably the thickness in the range of about 100 to
2,000 .mu.M.
[0032] In order to perform efficiently with adequate strength and
dimensional stability of the heat exchanger for exchanging heat of
fluids having different temperatures said heat exchanging plate may
be made from carbon steel, stainless steel, aluminium, titanium,
platinum, chromium, copper, or alloy of said materials, preferably
made from stainless steel 316 grade (SS316).
[0033] In one embodiment, the high temperature heat exchanging
plate 14 and the low temperature heat exchanging plate 16 may be
formed by stamping machine technique, photo chemical machine (PCM)
technique, or computer numerical control milling machine
technique.
[0034] In one embodiment, the inlet of the high temperature fluid
18a and the inlet of low temperature fluid 18b are disposed in an
opposite side of the heat exchanger in order to cause fluids having
different temperatures to flow in the counter-current direction,
wherein said fluids with different temperatures may have
temperature difference at least 1.degree. C., preferably
temperature difference at least 10.degree. C.
[0035] As being known by an ordinary person skilled in the art that
said flat heat exchanging plate 12, the high temperature heat
exchanging plate 14, and the low temperature heat exchanging plate
16 can be stacked in an alternating sequence from three plates and
more, they can be stacked in higher numbers in order to provide the
heat exchanger with many channels for heat exchanging of fluids
with high flow rate.
[0036] In order to compare the performance of the heat exchanger
according to the present invention to the heat exchanger comprising
the channel according to the prior art, the heat exchanger
according to this invention as the second embodiment comprising the
high temperature channel 15 and the low temperature channel 17
according to the appearance in FIG. 4 and the heat exchanger
comprising the high temperature channel and the low temperature
channel characterized in non-symmetric wavy pattern and straight
channel (according to the appearance in FIGS. 5 and 6 respectively)
were build and tested with computational flow dynamics model using
ANSYS Fluent Software, version 16.1 as being described below.
[0037] The Heat Exchanger According to this Invention
[0038] The Heat Exchanger 1
[0039] The thickness of each flat heat exchanging plate 12, the
high temperature heat exchanging plate 14, and the low temperature
heat exchanging plate 16 was 0.5 mm. The high temperature channel
15 and the low temperature channel 17 as shown in FIG. 4 had
average width (y) about 2,000 .mu.m, the curve length (x) about
2,000 .mu.m, and the curve radius (r) about 3,000 .mu.m. The length
of the channel was about 240 mm and the depth was about 1,000
.mu.m.
[0040] The Heat Exchanger 2
[0041] The thickness of each flat heat exchanging plate 12, the
high temperature heat exchanging plate 14, and the low temperature
heat exchanging plate 16 was 0.5 mm. The high temperature channel
15 and the low temperature channel 17 as shown in FIG. 4 had the
average width (y) about 2,000 .mu.m, the curve length (x) about
2,000 .mu.m, and the curve radius (r) about 4,000 .mu.m. The length
of the channel was about 240 mm and the depth was about 1,000
.mu.m.
[0042] The Heat Exchanger 3
[0043] The thickness of each flat heat exchanging plate 12, the
high temperature heat exchanging plate 14, and the low temperature
heat exchanging plate 16 was 0.5 mm. The high temperature channel
15 and the low temperature channel 17 as shown in FIG. 4 had
average width (y) about 2,000 .mu.m, the curve length (x) about
3,000 .mu.m, and the curve radius (r) about 3,000 .mu.m. The length
of the channel was about 240 mm and the depth was about 1,000
.mu.m.
[0044] The Heat Exchanger 4
[0045] The thickness of each flat heat exchanging plate 12, the
high temperature heat exchanging plate 14, and the low temperature
heat exchanging plate 16 was 0.5 mm. The high temperature channel
15 and the low temperature channel 17 as shown in FIG. 4 had the
average width (y) about 2,000 .mu.m, the curve length (x) about
3,000 .mu.m, and the curve radius (r) about 4,000 .mu.m. The length
of the channel was about 240 mm and the depth was about 1,000
.mu.m.
[0046] The Comparative Heat Exchanger
[0047] The Heat Exchanger a
[0048] The heat exchanger comprising the components as described in
the heat exchanger 1 except that the characters of the high and the
low temperature channel having a non-symmetric wavy pattern as
shown in FIG. 5 was used.
[0049] The Heat Exchanger B
[0050] The heat exchanger comprising the components as described in
the heat exchanger 2 except that the characters of the high and the
low temperature channels having the non-symmetric pattern as shown
in FIG. 5 was used.
[0051] The Heat Exchanger C
[0052] The heat exchanger comprising the components as described in
the heat exchanger 3 except that the characters of the high and the
low temperature channel having the non-symmetric pattern as shown
in FIG. 5 was used.
[0053] The Heat Exchanger D
[0054] The heat exchanger comprising the components as described in
the heat exchanger 4 except that the characters of the high and the
low temperature channel having the non-symmetric pattern as shown
in FIG. 5 was used.
[0055] The Heat Exchanger E
[0056] The heat exchanger comprising the components as described in
the heat exchanger 1 except that the characters of the high and the
low temperature channel having the straight path with about 2,000
.mu.m width as shown in FIG. 6 was used.
[0057] The heat exchanger comprising different characters of the
channel as described above was tested for heat exchanging
performance using ANSYS Fluent software version 16.1 with the
following parameters. Fluids used in the model were water at
different temperatures, wherein the high temperature fluid was
about 90.degree. C. and the low temperature fluid was about
10.degree. C. The said fluids flowed in the counter-current
direction with flow velocity in each path about 0.582 g/sec. The
results were shown in table 1 and FIG. 7.
[0058] Table 1 shows temperature of the high temperature fluids
outlet and the temperature of the low temperature fluids outlet
from the outlet of the heat exchanger comprising different
characters of the high temperature channel and the low temperature
channel.
TABLE-US-00001 Temperature of the high Temperature of the low Heat
temperature fluids outlet temperature fluids outlet exchanger
(.degree. C.) (.degree. C.) A 53.0 47.0 B 64.7 35.3 C 52.4 47.6 D
62.4 37.6 E 66.5 33.5 1 51.9 48.1 2 55.4 44.6 3 48.2 51.3 4 51.0
48.8
[0059] The performance of the heat exchanger can be considered from
the temperature of the high temperature fluid outlets and the
temperature of the low temperature fluid outlet as shown in table 1
and the heat transferred per fluid volume as shown in FIG. 7.
[0060] From FIG. 7, when comparing the heat exchanger according to
the invention 1 to the comparative heat exchanger A, E, the heat
exchanger according to the invention 2 to the comparative heat
exchanger B, E, the heat exchanger according to the invention 3 to
the comparative heat exchanger C, E, and the heat exchanger
according to the invention 4 to the comparative heat exchanger D,
E, it was found that the heat exchanger according to the present
invention gave higher heat transferred per fluid volume, wherein
the heat exchanger according to the invention 3 whose channel had
symmetric wavy pattern with average width about 2,000 .mu.m, the
curve length about 3,000 .mu.m, and the curve radius about 3,000
.mu.m provided highest performance.
[0061] Moreover, in order to compare the strength of the heat
exchanger according to present invention and the heat exchanger
comprising the channel according to the prior art, the heat
exchanger comprising different characters of the channel as
described above was tested using ANSYS Fluent software version
16.1. The parameters were set as the following. The heat exchanging
plates were made from 316 grade stainless steel (SS316). The
pressure of the high temperature fluid was about 1.5 MPa. The
pressure of the low temperature fluid was about 0.5 MPa. The heat
exchanging plates were fixed at the edges of the heat exchanging
plates. Results were shown in table 2, wherein volumetric
percentage of the heat exchanging plates in each stage of the
equivalent stress were calculated from the following equation:
Volume of the heat exchanging plate with equivalent stress in that
stage Volume of total heat exchanging plate .times. 100
##EQU00001##
[0062] Table 2 shows the comparison of the strength of the heat
exchanger comprising different characters of the temperature
channel and the low temperature channel.
TABLE-US-00002 Volumetric percentage of the heat exchanging Maximum
plates in equivalent stress in each stage equivalent Heat 0-3 3-6
6-9 stress exchanger MPa MPa MPa (MPa) A 87.1 12.2 0.7 7.69 B 86.7
12.3 1.0 7.56 C 90.7 9.1 0.2 6.69 D 88.7 10.8 0.5 7.19 E 86.1 12.8
1.1 7.16 1 87.2 12.0 0.8 7.41 2 86.8 12.3 1.0 7.36 3 90.4 9.4 0.2
6.66 4 88.9 10.7 0.4 7.11
[0063] Table 2 shows the comparison of the strength of the heat
exchanger according to present invention to the heat exchanger
according to the prior art, which could be considered from the
maximum equivalent stress and volumetric percentage of the heat
exchanging plates in each stage of the equivalent stress happened
to the heat exchanging plates of the heat exchanger during heat
transferring of the fluids with different temperatures. From the
table, the channel of the heat exchanger according to the invention
3 had the symmetric wavy pattern with the average width about 2,000
.mu.m, the curve length about 3 mm, and the curve radius about 3
mm, wherein the highest strength was considered from the lowest
maximum equivalent stress, the high volumetric percentage of the
heat exchanging plate in low equivalent stress stage (0-3 MPa), and
the high volumetric percentage of the heat exchanging plate in high
equivalent stress stage (6-9 MPa). Moreover, the maximum equivalent
stress of the heat exchanger according to this present invention
had a lower tensile yield strength than the 316 grade stainless
steel (about 207 MPa), used as sample material in strength test.
This showed that said heat exchanging plate of the heat exchanger
did not permanently deformed when operated at the above
conditions.
[0064] From the above results, it is confirmed that the heat
exchanger according to present invention has high performance in
heat transferring of the fluids with different temperatures, has
high strength, and can be used for the heat exchanging of the
fluids with highly different pressures as being said in the
objectives of this invention.
BEST MODE OF THE INVENTION
[0065] Best mode of the invention is as provided in the description
of the invention.
* * * * *