U.S. patent application number 13/753678 was filed with the patent office on 2014-07-31 for gas turbine engine integrated heat exchanger.
This patent application is currently assigned to General Electric Company. The applicant listed for this patent is General Electric Company. Invention is credited to Benignos Jorge Alejandro Carretero, William Joseph Antel, Sebastian Walter Freund.
Application Number | 20140209286 13/753678 |
Document ID | / |
Family ID | 50028860 |
Filed Date | 2014-07-31 |
United States Patent
Application |
20140209286 |
Kind Code |
A1 |
Freund; Sebastian Walter ;
et al. |
July 31, 2014 |
GAS TURBINE ENGINE INTEGRATED HEAT EXCHANGER
Abstract
A heat exchanger apparatus including at least one cooling
channel formed within and about an engine booster lip or an engine
nacelle and configured to receive a flow of a circulating working
fluid; and at least one fluid port communicating with the at least
one cooling channel and an exterior of the engine booster lip or
the engine nacelle.
Inventors: |
Freund; Sebastian Walter;
(Unterfoehring, DE) ; Antel; William Joseph;
(Freising, DE) ; Alejandro Carretero; Benignos Jorge;
(Munich, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company; |
|
|
US |
|
|
Assignee: |
General Electric Company
Schenectady
NY
|
Family ID: |
50028860 |
Appl. No.: |
13/753678 |
Filed: |
January 30, 2013 |
Current U.S.
Class: |
165/168 |
Current CPC
Class: |
F01P 3/12 20130101; Y02T
50/672 20130101; F01D 9/065 20130101; Y02T 50/675 20130101; F02C
7/14 20130101; Y02T 50/60 20130101 |
Class at
Publication: |
165/168 |
International
Class: |
F01P 3/12 20060101
F01P003/12 |
Claims
1. A heat exchanger apparatus comprising: at least one cooling
channel formed within and about an engine booster lip or an engine
annular fan casing and configured to receive a flow of a
circulating working fluid; and at least one fluid port
communicating with the at least one cooling channel and an exterior
of the engine booster lip or the engine annular fan casing.
2. The heat exchanger apparatus of claim 1, wherein the at least
one cooling channel is embedded within the booster lip and in
thermal contact with a root of at least one fan outlet guide vane
or fan outlet strut.
3. The heat exchanger apparatus of claim 2, wherein a plurality of
cooling channels are embedded within and about the booster lip and
wherein each of the plurality of cooling channels is in thermal
contact with the root of at least one fan outlet guide vane or fan
outlet strut.
4. The heat exchanger apparatus of claim 2, wherein the at least
one cooling channel is configured about at least a portion of a
circumference of the engine booster lip.
5. The heat exchanger apparatus of claim 4, wherein the at least
one cooling channel is configured about a complete circumference of
the engine booster lip.
6. The heat exchanger apparatus of claim 1, wherein the at least
one cooling channel is embedded within and about the engine annular
fan casing and in thermal contact with a thermal plate on an outer
surface of the engine annular fan casing.
7. The heat exchanger apparatus of claim 6, wherein the thermal
plate is flush mounted to the outer surface of the engine annular
fan casing.
8. The heat exchanger apparatus of claim 6, wherein the thermal
plate is integrally formed with the outer surface of the engine
annular fan casing.
9. The heat exchanger apparatus of claim 6, wherein a plurality of
cooling channels are embedded within and about the engine annular
fan casing and wherein each of the plurality of cooling channels is
in thermal contact with the thermal plate.
10. The heat exchanger apparatus of claim 6, wherein the at least
one cooling channel is configured about at least a portion of a
circumference of the engine annular fan casing.
11. The heat exchanger apparatus of claim 10, wherein the at least
one cooling channel is configured about a complete circumference of
the engine annular fan casing.
12. A heat exchanger apparatus comprising: a plurality of cooling
channels integrally formed within and about at least a portion of a
circumference of one of an engine booster lip or an engine nacelle
and wherein each of the plurality of cooling channels is configured
to receive a flow of circulating working fluid; and inlet and
outlet ports communicating with the at least one cooling channel
and an exterior of the engine booster lip or the engine
nacelle.
13. The heat exchanger apparatus of claim 12, wherein the plurality
of cooling channels comprises a plurality of channels oriented
circumferentially about the one an engine booster lip or an engine
nacelle.
14. The heat exchanger apparatus of claim 13, wherein each of the
plurality of cooling channels is embedded within the booster lip
and in thermal contact with a base of at least one fan outlet guide
vane or fan outlet strut.
15. The heat exchanger apparatus of claim 13, wherein the plurality
of cooling channels are configured about at least a portion of a
circumference of the engine booster lip.
16. The heat exchanger apparatus of claim 13, wherein each of the
plurality of cooling channels is embedded within and about at least
a portion of a circumference of the engine nacelle and in thermal
contact with a thermal plate on an outer surface of the engine
nacelle.
17. The heat exchanger apparatus of claim 16, wherein the thermal
plate is one of mounted to the outer surface of the engine nacelle
or integrally formed with the outer surface of the engine
nacelle.
18. An engine comprising: a core engine; and a heat exchanger
apparatus comprising: at least one cooling channel integrally
formed within and about an engine booster lip or an engine annular
fan casing and configured to receive a flow of a circulating
working fluid; and at least one fluid port communicating with the
at least one flush mounted cooling channel and an exterior of the
engine booster lip or the engine annular fan casing, wherein the at
least one cooling channel is configured to provide an increase in
the heat transfer coefficient of the heat exchanger apparatus while
minimizing aerodynamic losses and specific fuel consumption
(SFC).
19. The engine of claim 18, wherein the at least one cooling
channel is configured about at least a portion of a circumference
of the engine booster lip.
20. The engine of claim 18, wherein at least one cooling channel is
embedded within and about the engine annular fan casing and in
thermal contact with a thermal plate on an outer surface of the
engine annular fan casing.
Description
BACKGROUND
[0001] This invention relates generally to turbomachines, and more
particularly to the design of an enhanced heat exchanger, in the
form of an air-cooled surface cooler, for use in turbomachines.
[0002] Modern turbofan/turbojet engines have an ever-increasing
demand of cooling, including gearbox oil, cooling air and
electronics, while at the same time their efficiency has to be
pushed ever higher. Currently air-cooled oil coolers are usually
plate-fin type "brick" heat exchangers that are mounted within the
bypass channel to receive flow from the engine intake or bypass
stream or from a separate air-intake in the nacelle or fan casing.
New designs have mitigated the high drag of this design due to the
plate-fin exchanger sitting in the bypass channel by utilizing a
surface cooler that is mounted flush with the aft fan cowling.
However, the space in this region of the engine is limited and
current designs utilize nearly all the available space. As a
result, newer engine technologies, which have more heat that must
be dissipated, will be thermally constrained due to the lack of
space available onto which the cooler may be formed. In addition,
current heat exchangers such as these plate-fin "brick" coolers
obstruct the air flow and incur aerodynamic losses as the cooling
requirements grow. These losses mean increased specific fuel
consumption.
[0003] By using a surface cooler where only the cooler fins project
into the engine air bypass flow, the drag of the oil cooler heat
exchanger has been reduced over that of a traditional plate-fin
cooler. However increasing heat loads requires that the surface
cooler will need to be larger in size. Aircraft weight is a current
concern in the current industry, with a decrease in aircraft weight
resulting in an efficiency increase. In addition, new engines are
becoming space constrained, making the size and weight of these
types of plate-fin coolers prohibitive.
[0004] Prior attempts to overcome this problem have utilized a coil
of tubing within the outlet guide vane/strut and in thermal contact
with the surface of the strut. As oil is flowed through the tubing
heat is transferred to the bypass air stream through the strut
skin. In addition, systems that utilize various air scoops in the
fan bypass flow, thereby directing air through a plate-fin heat
exchanger have been utilized, as well as the use of actuators to
push the plate-fin heat exchange in and out of the fan bypass flow
or alternatively block part of the air scoop. By modulating the
amount of air utilized by the heat exchanger only the minimal
amount of airflow required is utilized. While resulting in the
cooling of oil, as well as additional aircraft components, these
systems may be thermally limited, cost prohibitive to fabricate and
implement an increase drag on the aircraft.
[0005] In an attempt to increase efficiency of these known surface
coolers, there is a desire for an improved air cooled oil cooler
that will enable the cooler to be implemented into newer engine
technologies with increased heat dissipation requirements, while
remaining cost effective and having minimal aerodynamic drag as
compared to current designs, and therefore provide an overall more
efficient system.
BRIEF SUMMARY
[0006] These and other shortcomings of the prior art are addressed
by the present disclosure, which provides a heat exchanger
apparatus.
[0007] In accordance with an embodiment, provided is a heat
exchanger apparatus including at least one cooling channel formed
within and about an engine booster lip or an engine annular fan
casing and configured to receive a flow of a circulating working
fluid; and at least one fluid port communicating with the at least
one cooling channel and an exterior of the engine booster lip or
the engine annular fan casing.
[0008] In accordance with another embodiment, provided is a heat
exchanger apparatus including a plurality of cooling channels
integrally formed within and about at least a portion of a
circumference of one of an engine booster lip or an engine nacelle
and wherein each of the plurality of cooling channels is configured
to receive a flow of circulating working fluid; and inlet and
outlet ports communicating with the at least one cooling channel
and an exterior of the engine booster lip or the engine
nacelle.
[0009] In accordance with yet another embodiment, provided is and
engine including a core engine; and a heat exchanger apparatus. The
heat exchanger apparatus including at least one cooling channel
integrally formed within and about an engine booster lip or an
engine annular fan casing and configured to receive a flow of a
circulating working fluid; and at least one fluid port
communicating with the at least one flush mounted cooling channel
and an exterior of the engine booster lip or the engine annular fan
casing. The at least one cooling channel is configured to provide
an increase in the heat transfer coefficient of the heat exchanger
apparatus while minimizing aerodynamic losses and specific fuel
consumption (SFC).
[0010] Other objects and advantages of the present disclosure will
become apparent upon reading the following detailed description and
the appended claims with reference to the accompanying
drawings.
BRIEF DESCRIPTION OF THE FIGURES
[0011] The above and other features, aspects, and advantages of the
present disclosure will become better understood when the following
detailed description is read with reference to the accompanying
drawings in which like characters represent like parts throughout
the drawings, wherein:
[0012] FIG. 1 is a schematic cross-sectional view of a gas turbine
engine incorporating a heat exchanger system constructed according
to an aspect of the present disclosure;
[0013] FIG. 2 is an enlarged view of a portion of the gas turbine
engine of FIG. 1;
[0014] FIG. 3 is a side view of an outlet guide vane and a portion
of a booster lip in contact with a root of the outlet guide vane
constructed in accordance with an aspect of the present
disclosure;
[0015] FIG. 4 is a perspective view of a portion of the gas turbine
engine of FIG. 1 illustrating the booster lip and associated outlet
guide vanes;
[0016] FIG. 5 a schematic cross-sectional view of a gas turbine
engine incorporating a heat exchanger system constructed according
to another aspect of the present disclosure;
[0017] FIG. 6 is an enlarged view of a portion of the gas turbine
engine of FIG. 5; and
[0018] FIG. 7 is a perspective view of an exterior of the gas
turbine engine of FIG. 5.
DETAILED DESCRIPTION
[0019] The invention will be described for the purposes of
illustration only in connection with certain embodiments; however,
it is to be understood that other objects and advantages of the
present disclosure will be made apparent by the following
description of the drawings according to the disclosure. While
preferred embodiments are disclosed, they are not intended to be
limiting. Rather, the general principles set forth herein are
considered to be merely illustrative of the scope of the present
disclosure and it is to be further understood that numerous changes
may be made without straying from the scope of the present
disclosure.
[0020] Embodiments disclosed herein relate to heat exchangers and
more particularly to enhanced heat exchangers for use in an engine
such as an aircraft engine. The exemplary heat exchangers may be
used for providing efficient cooling. Further, the term "heat
exchangers" as used herein may be used interchangeably with the
term "surface coolers". As used herein, the heat exchangers/surface
coolers are applicable to various types of turbomachinery
applications such as, but not limited to, turbojets, turbo fans,
turbo propulsion engines, aircraft engines, gas turbines, steam
turbines, wind turbines, and water turbines.
[0021] Preferred embodiments of the present disclosure are
illustrated in the figures with like numerals being used to refer
to like and corresponding parts of the various drawings. It is also
understood that terms such as "top", "bottom", "outward", "inward",
and the like are words of convenience and are not to be construed
as limiting terms. It is to be noted that the terms "first,"
"second," and the like, as used herein do not denote any order,
quantity, or importance, but rather are used to distinguish one
element from another. The terms "a" and "an" do not denote a
limitation of quantity, but rather denote the presence of at least
one of the referenced item. The modifier "about" used in connection
with a quantity is inclusive of the stated value and has the
meaning dictated by the context (e.g., includes the degree of error
associated with measurement of the particular quantity).
[0022] Referring to the drawings wherein identical reference
numerals denote the same elements throughout the various views,
FIGS. 1 and 2 depict schematic illustrations of an exemplary
aircraft engine assembly 10 in accordance with the present
disclosure. It is noted that the portion of the engine assembly 10
illustrated in FIG. 2 is indicated by dotted line in FIG. 1. The
engine assembly 10 has a longitudinal center line or axis 12 and an
outer stationary annular casing 14 disposed concentrically about
and coaxially along the axis 12. In the exemplary embodiment, the
engine assembly 10 includes a fan assembly 16, a booster compressor
18, a core gas turbine engine 20, and a low-pressure turbine 22
that may be coupled to the fan assembly 16 and the booster
compressor 18. The fan assembly 16 includes a plurality of rotor
fan blades 24 that extend substantially radially outward from a fan
rotor disk 26, as well as a plurality of structural strut members
28 and outlet guide vanes ("OGVs") 29 that may be positioned
downstream of the rotor fan blades 24. In this example, separate
members are provided for the aerodynamic and structural functions.
In other configurations, each of the OGVs 29 may be both an
aero-turning element and a structural support for an annular fan
casing (described presently). While the concepts of the present
disclosure will be described using the outlet guide vane 29 as an
example of a portion of the heat exchanger apparatus, it will be
understood that those concepts are applicable to any aero-turning
or stationary airfoil-type structure within the engine assembly
10.
[0023] The core gas turbine engine 20 includes a high-pressure
compressor 30, a combustor 32, and a high-pressure turbine 34. The
booster compressor 18 includes a plurality of rotor blades 36 that
extend substantially radially outward from a compressor rotor disk
38 coupled to a first drive shaft 40. The high-pressure compressor
30 and the high-pressure turbine 34 are coupled together by a
second drive shaft 42. The first and second drive shafts 40 and 42
are rotatably mounted in bearings 43 which are themselves mounted
in a fan frame 45 and a turbine rear frame 47. The fan frame 45 has
a central hub 49 connected to the annular fan casing 51. The engine
assembly 10 also includes an intake side 44, a core engine exhaust
side 46, and a fan exhaust side 48.
[0024] During operation, the fan assembly 14 compresses air
entering the engine assembly 10 through the intake side 44. The
airflow exiting the fan assembly 14 is split such that a portion 50
of the airflow is channeled into the booster compressor 18, as
compressed airflow, and a remaining portion 52 of the airflow
bypasses the booster compressor 18 and the core gas turbine engine
20 and exits the engine assembly 10 through the fan exhaust side 48
as bypass air. This bypass air portion 52 flows past and interacts
with the structural strut members 28 and the outlet guide vanes 29
creating unsteady pressures on the stator surfaces as well as in
the surrounding airflow that radiate as acoustic waves. The
plurality of rotor blades 24 compress and deliver the compressed
airflow 50 towards the core gas turbine engine 20. Furthermore, the
airflow 50 is further compressed by the high-pressure compressor 30
and is delivered to the combustor 32. Moreover, the compressed
airflow 50 from the combustor 32 drives the rotating high-pressure
turbine 34 and the low-pressure turbine 22 and exits the engine
assembly 10 through the core engine exhaust side 46.
[0025] As previously noted, in certain presently available
commercial engines heat exchangers are employed. Furthermore, high
heat loads may lead to sub-optimal performance of certain heat
exchangers. In accordance with exemplary aspects of the present
technique, an apparatus 54 configured to function as a heat
exchanger is presented. More particularly, the exemplary apparatus
54 may be configured to address the heat exchange requirements of a
turbomachine such as an aircraft engine, for example. Hereinafter,
the term "heat exchanger" may be used to refer to the apparatus 54
configured to facilitate cooling of the turbomachine.
[0026] In an embodiment, the booster compressor 18 and some or all
of the structural fan outlet struts 28 in the engine assembly 10
comprise a portion of a heat exchanger integrated into their
structures. In another embodiment, the booster compressor 18 and
some or all of the OGVs 29 in the engine assembly 10 comprise a
portion of a heat exchanger integrated into their structures. In
yet another embodiment, the booster compressor 18 and some or all
of the structural fan outlet struts 28 and the OGVs 29 in the
engine assembly 10 comprise a portion of a heat exchanger
integrated into their structures.
[0027] Referring now to FIG. 3, illustrated is one of the OGVs 29
of the engine assembly 10, illustrated in more detail. In general,
the OGV 29 comprises an airfoil 60 having a leading edge 62, a
trailing edge 64, a tip 66 and a root 68. An arcuate inner platform
70 is disposed at the root 68 of the airfoil 60.
[0028] The airfoil 60 is assembled from a body (not shown) and a
cover 72. The body and the cover 72 are both made from a material
with suitable strength and weight characteristics for the intended
application. In addition, illustrated in FIG. 3 is an interior wall
74 of a booster lip 76 of the booster compressor 18, illustrating
at least one cooling channel 78 integrally formed within and about
the engine booster lip 76 and in contact with the root 68 of the
OGVs 29. In an embodiment, the booster lip 76 includes a plurality
of cooling channels 78 formed therein.
[0029] Referring specifically to FIG. 4, at least one cooling
channel 78 provides a space within the booster lip 76 for a flow of
working fluid, for example lubrication oil. In an embodiment, the
at least one cooling channel 78 is integral to the booster lip, or
in other words, the at least one cooling channel 78 is defined by
the structure of the booster lip 76 itself, rather than any
intermediate structure, such as filler materials. In an alternate
embodiment, the at least one cooling channel 78 is defined by
extruded channels, tubes, or piping that are embedded within the
structure of the booster lip 76.
[0030] In operation, the working fluid is in intimate contact with
the root 68 of the OGV 29 via the at least one cooling channel 78.
This results in the airfoil 60 of the OGV 29 acting as a cooling fm
for the working fluid in the at least one cooling channel 78 on the
booster compressor circumference, maximizing the heat transfer
rate. The interior of the at least one cooling channel 78, i.e. its
size, shape, surface texture, and arrangement of internal walls or
other features, may be configured to maximize heat transfer between
the working fluid and the OGV 29, minimize pressure loses, and so
forth. As used herein the term "channel" refers to the entire
volume available for flow of working fluid within the booster lip
76, regardless of whether it is configured as a single cooling
channel or a plurality of cooling channels.
[0031] As shown in FIGS. 3 and 4, the at least one cooling channel
78 is configured as a plurality of parallel channels 79 running in
a generally radial (i.e. spanwise) direction and separated by walls
or ribs. In an embodiment, the channels 79 are arranged into
"groups" 80, an eight-channel group arrangement being shown,
providing working fluid communication with a single OGV 29.
Cross-passages (not shown) may interconnect the groups 80 to define
a continuous flow path circumferentially about the booster
compressor 18, and more particularly the booster lip 76. In an
embodiment, the cross-passages are configured to provide for a flow
of the working fluid about at least a portion of the circumference
of the booster lip 76. In another embodiment, the cross-passages
are configured to provide for a flow of the working fluid about a
complete circumference of the booster lip 76. The at least one
cooling channel 78 may be formed, for example, by a machining
process. In the illustrated example, the width of each of the
plurality of parallel channels 79 is approximately 6.4 mm (0.25
in.).
[0032] Referring now to FIGS. 5-7, illustrated is another
embodiment of an engine assembly including a heat exchanger
apparatus according to this disclosure. FIGS. 5 and 6 depict
schematic illustrations of an exemplary aircraft engine assembly
80, generally similar to aircraft engine assembly 10 of FIGS. 1-2,
in accordance with the present disclosure.
[0033] As previously noted, in certain presently available
commercial engines heat exchangers are employed. In accordance with
exemplary aspects of the present technique, an apparatus 82
configured to function as a heat exchanger is presented. More
particularly, the apparatus 82 may be configured to address the
heat exchange requirements of a turbomachine such as an aircraft
engine, for example. Hereinafter, the term "heat exchanger" may be
used to refer to the apparatus 82 configured to facilitate cooling
of the turbomachine. In the embodiment illustrated in FIGS. 5-7,
the heat exchanger apparatus 82 may be comprised of at least one
cooling channel 84 disposed within and about an engine nacelle,
also referred to herein interchangeably as the annular fan casing,
51 and configured to receive a flow of a circulating working fluid
therein.
[0034] In the embodiment illustrated in FIGS. 5-7, a plurality of
cooling channels 84 are formed at least partially about a
circumference of the annular fan casing 51 and in thermal contact
with a thermal plate 86 on the annular fan casing 51. In an
embodiment, the thermal plate 86 is comprised of any metal or
composite material capable of conducting heat. The plurality of
channels 84 are configured to aid in cooling a working fluid that
may be heated by various parts of the engine assembly 80. As will
be appreciated, the working fluid may be heated by parts of the
engine assembly 80 such as bearings. The heated fluid is channeled
through the heat exchanger 82 via the plurality of channels 84. The
heat from the fluid may be transferred from the walls of the
plurality of channels 84 and dissipated into the thermal plate 86
and surrounding ambient air surrounding the annular fan casing 51,
or nacelle structure. In an embodiment, this fluid may then be
carried back to the parts in engine assembly 80.
[0035] FIG. 7 illustrates a perspective view of a portion of the
exemplary heat exchanger apparatus 82 with the thermal plate 86 on
an outer surface of the annular fan casing 51. In an embodiment,
the thermal plate 86 may be integrally formed, or mounted flush to
the annular fan casing 51 so as to provide minimal to no effect on
the engine aerodynamics In the illustrated embodiment, the heat
exchanger 82 operates without the need for a fin structures,
relying on movement of the airflow over the engine fan casing 51,
and thus the thermal plate 86, to provide dissipation of the heat.
At high altitudes, the heat exchanger 82 operates extremely
efficiently due to the large temperature differential between the
working fluid and the ambient air passing over the engine fan
casing 51.
[0036] In operation, hot working fluid from the engine (e.g.
lubricating oil or accessory cooling oil) is ported via at least
one inlet and outlet port 90 (FIG. 1) communicating with the at
least one cooling channel 78, 84 and an exterior of the engine
booster lip 76 or the annular fan casing 51. The working fluid
flows through the at least one cooling channel 78, 84 where heat is
removed from the fluid by transfer to the airflow surrounding the
OGV (in this case fan bypass flow) 29 (FIG. 1) or the engine fan
casing 51 (FIG. 5). The heated oil then passes back to the
remainder of the oil system. It will be understood that the oil
system incorporates pumps, filters, lines, valves, tanks, and other
equipment as needed to provide a flow of pressurized oil. Such
components are well-known and therefore not illustrated here.
[0037] Using the concepts described herein, existing turbine engine
structures, such as the booster compressor in combination with the
OGVs or structural struts, or an engine fan casing may incorporate
an oil cooling function, in addition to aero-turning and/or
structural functions. The oil cooling function is performed
utilizing exiting engine structures, without the need for the
addition of a traditional plate-and-fin heat exchanger.
[0038] This concept has several advantages. Among them are minimal
aerodynamic losses, as well as providing an increase in volume flow
and propulsion power by permitting any heat that is added to the
bypass flow after the fan, to be retained. A significant
improvement in specific fuel consumption ("SFC") is expected as
well.
[0039] The foregoing has described a heat exchanger for a gas
turbine engine and a method for its operation. While the present
disclosure has been described with respect to a limited number of
embodiments, those skilled in the art, having benefit of this
disclosure, will appreciate that other embodiments may be devised
which do not depart from the scope of the disclosure as described
herein. While the present disclosure has been described with
reference to exemplary embodiments, it will be understood by those
skilled in the art that various changes may be made and equivalents
may be substituted for elements thereof without departing from the
scope of the disclosure. In addition, many modifications may be
made to adapt a particular situation or material to the teachings
of the present disclosure without departing from the essential
scope thereof. Therefore, it is intended that the present
disclosure not be limited to the particular embodiment disclosed as
the best mode contemplated for carrying out the disclosure. It is,
therefore, to be understood that the appended claims are intended
to cover all such modifications and changes as fall within the true
spirit of the disclosure.
* * * * *