U.S. patent application number 15/043517 was filed with the patent office on 2017-08-17 for method and aircraft for providing bleed air to an environmental control system.
The applicant listed for this patent is GE AVIATION SYSTEMS LLC. Invention is credited to JULIAN ALEXANDER OPIFICIUS, DOMINIQUE PATRICK SAUTRON.
Application Number | 20170233081 15/043517 |
Document ID | / |
Family ID | 58213330 |
Filed Date | 2017-08-17 |
United States Patent
Application |
20170233081 |
Kind Code |
A1 |
SAUTRON; DOMINIQUE PATRICK ;
et al. |
August 17, 2017 |
METHOD AND AIRCRAFT FOR PROVIDING BLEED AIR TO AN ENVIRONMENTAL
CONTROL SYSTEM
Abstract
A method and aircraft for providing bleed air to environmental
control systems of an aircraft using a gas turbine engine,
including determining a bleed air demand for the environmental
control systems, supplying low pressure and high pressure bleed air
to the environmental control systems, wherein the proportional
supplying is controlled such that the conditioned air stream meets
the determined bleed air demand.
Inventors: |
SAUTRON; DOMINIQUE PATRICK;
(CHICAGO, IL) ; OPIFICIUS; JULIAN ALEXANDER; (ELK
RIVER, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GE AVIATION SYSTEMS LLC |
Grand Rapids |
MI |
US |
|
|
Family ID: |
58213330 |
Appl. No.: |
15/043517 |
Filed: |
February 13, 2016 |
Current U.S.
Class: |
60/783 |
Current CPC
Class: |
B64D 13/06 20130101;
B64D 2013/0648 20130101; Y02T 50/50 20130101; F05D 2220/323
20130101; B64D 15/00 20130101; F02C 9/18 20130101; Y02T 50/56
20130101; B64D 13/02 20130101; B64D 2013/0607 20130101; B64D
2013/0618 20130101; F02C 6/08 20130101 |
International
Class: |
B64D 13/06 20060101
B64D013/06; B64D 13/02 20060101 B64D013/02; F02C 9/18 20060101
F02C009/18; B64D 15/00 20060101 B64D015/00 |
Claims
1. A method of providing bleed air to environmental control systems
(ECS) using a gas turbine engine, the method comprising:
determining a bleed air demand for the ECS; proportionally
supplying low pressure and high pressure bleed air from a
compressor of the gas turbine engine to a turbine section and
compressor section of a turbo air cycle machine, with the turbine
section emitting a cooled air stream and the compressor section
emitting a compressed air stream; and combining the cooled air
stream and the compressed air stream to form a conditioned air
stream; wherein the proportional supplying is controlled such that
the conditioned air stream meets the determined bleed air
demand.
2. The method of claim 1 wherein the determining the bleed air
demand comprises determining at least one of air pressure or air
temperature demand for the ECS.
3. The method of claim 2 wherein the determining the bleed air
demand comprises determining both the air pressure and the air
temperature demand for the ECS.
4. The method of claim 1 wherein the bleed air demand is a function
of at least one of number of aircraft passengers, aircraft flight
phase, or operational subsystems of the ECS.
5. The method of claim 1 wherein proportionally supplying low
pressure and high pressure bleed air comprises supplying 100% of
one of the low pressure or high pressure bleed air and 0% of the
other of the low pressure and high pressure bleed air.
6. The method of claim 1 wherein proportionally supplying low
pressure and high pressure bleed air comprises step-wise
proportionally supplying the low pressure and high pressure bleed
air.
7. The method of claim 6 wherein the step-wise proportionally
supplying the low pressure and high pressure bleed air is a
function of the aircraft flight phase.
8. The method of claim 7 wherein the aircraft flight phase is one
of ground idle, taxi, takeoff, climb, cruise, descent, hold, and
landing.
9. The method of claim 6 wherein the step-wise proportionally
supply the low pressure and high pressure bleed air is a function
of the rotational speed of the gas turbine engine.
10. The method of claim 6 wherein the rotational speed of the gas
turbine engine comprises predetermined speed ranges for the gas
turbine engine.
11. The method of claim 1 wherein proportionally supplying low
pressure and high pressure bleed air comprises continuously
proportionally supplying the low pressure and high pressure bleed
air.
12. An aircraft comprising: an environmental control system (ECS)
having a bleed air inlet; a gas turbine engine having a low
pressure bleed air supply and a high pressure bleed air supply; a
turbo air cycle machine having rotationally coupled turbine and
compressor sections; an upstream turbo-ejector fluidly coupling the
low and high pressure bleed air supplies to the turbine and
compressor sections; and a downstream turbo-ejector fluidly
combining fluid outputs from the turbine and compressor sections
into a common flow that is supplied to the bleed air inlet of the
ECS.
13. The aircraft of claim 12 wherein the environmental control
system comprises an air-conditioning subsystem and a de-icing
subsystem.
14. The aircraft of claim 12 wherein the upstream turbo-ejector
comprises directly fluidly coupling the high pressure bleed air
supply with the turbine section.
15. The aircraft of claim 14 wherein the upstream turbo-ejector
comprises simultaneously supplying the low pressure bleed air
supply to the compressor section and the high pressure bleed air
supply.
16. The aircraft of claim 15 wherein the upstream turbo-ejector is
configured to entrain at least a portion of the low pressure bleed
air in the high pressure bleed air supply coupled with the turbine
section.
17. The aircraft of claim 12 further comprising a controller module
configured to controllably operate at least one of the upstream
turbo-ejector or downstream turbo-ejector.
18. A method of providing bleed air to an environmental control
systems (ECS) of an aircraft using a gas turbine engine, the method
comprising proportionally supplying low pressure and high pressure
bleed air from a compressor of the gas turbine engine to a turbo
air cycle machine to precondition the bleed air according to
operational demands of the ECS.
19. The method of claim 18 further comprising determining the
operational demands of the ECS by way of determining at least one
of air pressure or air temperature demand for the ECS.
20. The method of claim 18 wherein proportionally supplying low
pressure and high pressure bleed air comprises supplying 100% of
one of the low pressure or high pressure bleed air and 0% of the
other of the low pressure and high pressure bleed air.
Description
BACKGROUND OF THE INVENTION
[0001] Contemporary aircraft have bleed air systems that take hot
air from the engines of the aircraft for use in other systems on
the aircraft including environmental control systems (ECS) such as
air-conditioning, pressurization, and de-icing. The ECS can include
limits on the pressure or temperature of the bleed air received
from the bleed air systems. Currently, aircraft engine bleed
systems make use of a pre-cooler heat exchanger to pre-condition
the hot air from the engines to sustainable temperatures, as
required or utilized by the other aircraft systems. The pre-cooler
heat exchangers produce waste heat, which is typically exhausted
from the aircraft without utilization.
BRIEF DESCRIPTION OF THE INVENTION
[0002] In one embodiment, a method of providing bleed air to
environmental control systems (ECS) of an aircraft using a gas
turbine engine, includes determining a bleed air demand for the
ECS, proportionally supplying low pressure and high pressure bleed
air from a compressor of the gas turbine engine to a turbine
section and compressor section of a turbo air cycle machine, with
the turbine section emitting a cooled air stream and the compressor
section emitting a compressed air stream, and combining the cooled
air stream and the compressed air stream to form a conditioned air
stream. The proportional supplying is controlled such that the
conditioned air stream meets the determined bleed air demand.
[0003] In another embodiment, an aircraft includes an environmental
control system (ECS) having a bleed air inlet, a gas turbine engine
having a low pressure bleed air supply and a high pressure bleed
air supply, a turbo air cycle machine having rotationally coupled
turbine and compressor sections, an upstream turbo-ejector fluidly
coupling the low and high pressure bleed air supplies to the
turbine and compressor sections, and a downstream turbo-ejector
fluidly combining fluid outputs from the turbine and compressor
sections into a common flow that is supplied to the bleed air inlet
of the ECS.
[0004] In yet another embodiment, A method of providing bleed air
to an environmental control systems (ECS) of an aircraft using a
gas turbine engine, the method comprising proportionally supplying
low pressure and high pressure bleed air from a compressor of the
gas turbine engine to a turbo air cycle machine to precondition the
bleed air according to operational demands of the ECS.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] In the drawings:
[0006] FIG. 1 is a perspective view of an aircraft having a bleed
air system in accordance with various aspects described herein.
[0007] FIG. 2 is a schematic view of a portion of an exemplary
aircraft gas turbine engine in accordance with various aspects
described herein.
[0008] FIG. 3 is a schematic view of the aircraft gas turbine
engine bleed air system in accordance with various aspects
described herein.
[0009] FIG. 4 is an example a flow chart diagram of demonstrating a
method of providing bleed air to the environmental control system
in accordance with various aspects described herein.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0010] FIG. 1 illustrates an embodiment of the disclosure, showing
an aircraft 10 that can include a bleed air system 20, only a
portion of which has been illustrated for clarity purposes. As
illustrated, the aircraft 10 can include multiple engines 12, such
as gas turbine engines 12, a fuselage 14, a cockpit 16 positioned
in the fuselage 14, and wing assemblies 18 extending outward from
the fuselage 14. The aircraft can also include an environmental
control system (ECS) 48. The ECS 48 is schematically illustrated in
the fuselage 14 of the aircraft 10 and is fluidly coupled with the
bleed air system 20 to receive a supply of bleed air from the
engines 12.
[0011] The bleed air system 20 can be connected to each of the
engines 12 such that high temperature, high pressure air, or a
combination thereof received from the engines 12 can be used within
the aircraft 10 for environmental control of the aircraft 10. More
specifically, an engine can include a set of bleed ports 24
arranged along the gas turbine engine 12 length or operational
stages such that bleed air can be received, captured, or removed
from the gas turbine engine 12 as the corresponding set of bleed
ports 24. In this sense, various bleed air characteristics,
including but not limited to, bleed air mass flow rate (for
example, in pounds per minute), bleed air temperature or bleed air
pressure, can selected based on the desired operation or bleed air
demand of the bleed air system 20. As used herein, the
environmental control of the aircraft 10, that is, the ECS 48 of
the aircraft 10, can include subsystems for anti-icing or de-icing
a portion of the aircraft, for pressurizing the cabin or fuselage,
heating or cooling the cabin or fuselage, and the like. The
operation of the ECS 48 can be a function of at least one of the
number of aircraft 10 passengers, aircraft 10 flight phase, or
operational subsystems of the ECS 48. Examples of the aircraft 10
flight phase can include, but is not limited to ground idle, taxi,
takeoff, climb, cruise, descent, hold, and landing. The demand of
the bleed air system 20 by the ECS can be dynamic as, for example,
subsystems are needed based on aircraft 10 conditions.
[0012] While a commercial aircraft 10 has been illustrated, it is
contemplated that embodiments of the invention can be used in any
type of aircraft 10. Further, while two engines 12 have been
illustrated on each wing assembly 18, it will be understood that
any number of engines 12 including a single gas turbine engine 12
on each wing assembly 18, or even a single gas turbine engine
mounted in the fuselage 14 can be included.
[0013] FIG. 2 illustrates a cross section of the gas turbine engine
12 of the aircraft 10. The gas turbine engine 12 can include, in a
serial relationship, a fan 22, a compressor section 26, a
combustion section 25, a turbine section 27, and an exhaust section
29. The compressor section 26 can include, in a serial
relationship, a multi-stage low pressure compressor 30 and a
multi-stage high pressure compressor 32.
[0014] The gas turbine engine 12 is also shown including a low
pressure bleed port 34 arranged to pull, draw, or receive low
pressure bleed air from the low pressure compressor 30 and a high
pressure bleed port 36 arranged to pull, draw, or receive high
pressure bleed air from the high pressure compressor 32. The bleed
ports 34, 36 are also illustrated coupled with various sensors 28.
By way of non-limiting example, the sensors 28 can include
respective temperature sensors, respective flow rate sensors, or
respective pressure sensors. While only a single low pressure bleed
port 34 is illustrated, the low pressure compressor 30 can include
a set of low pressure bleed ports 34 arranged at multiple stages of
the compressor 30 to pull, draw, or receive various bleed air
characteristics, including but not limited to, bleed air mass flow
rate, bleed air temperature, or bleed air pressure. Similarly,
while only a single high pressure bleed port 36 is illustrated, the
high pressure compressor 32 can include a set of high pressure
bleed ports 36 to pull, draw, or receive various bleed air
characteristics, including but not limited to, bleed air mass flow
rate, bleed air temperature, or bleed air pressure. Non-limiting
embodiments of the disclosure can further include configurations
wherein at least one of the low or high pressure bleed port 34, 36
can include a bleed port from an auxiliary power units (APU) or
ground cart units (GCU) such that the APU or GCU can provide an
augmented pressure and conditioned temperature airflow in addition
to or in place of the engine bleed ports 34, 36.
[0015] During gas turbine engine 12 operation, the rotation of the
fan 22 draws in air, such that at least a portion of the air is
supplied to the compressor section 26. The air is pressurized to a
low pressure by the low pressure compressor 30, and then is further
pressurized to a high pressure by the high pressure compressor 32.
At this point in the engine operation, the low pressure bleed port
34 and the high pressure bleed port 36 draw, respectively low
pressure air from the low pressure compressor 30 and high pressure
air from the high pressure compressor 32 and supply the air to the
ECS 48. High pressure air not drawn by the high pressure bleed port
36 is delivered to the combustion section 25, wherein the high
pressure air is mixed with fuel and combusted. The combusted gases
are delivered downstream to the turbine section 27, which are
rotated by the gases passing through the turbine section 27. The
rotation of the turbine section 27, in turn, rotates the fan 22 and
the compressor section 26 upstream of the turbine section 27.
Finally, the combusted gases are exhausted from the gas turbine
engine 12 through the exhaust section 29.
[0016] FIG. 3 illustrates a schematic view of the bleed air system
20 of the aircraft 10. As shown, the bleed air system 20 can
include a turbo air cycle machine 38 fluidly coupled upstream with
the set of gas turbine engine (shown only as a single gas turbine
engine 12) and fluidly coupled downstream with the ECS 48. The
turbo air cycle machine 38 can include a turbine 40 and a
compressor 42, such as a turbo compressor, rotatably coupled on a
common shaft with the turbine 40. The bleed air system 20 of the
turbo air cycle machine 38 can include a flow mixer or
turbo-ejector 44 located downstream from the machine 38.
[0017] The low pressure and high pressure bleed ports 34, 36 can be
fluidly coupled with the turbo air cycle machine 38 by way of a
proportional mixing or controllable valve assembly 45. In one
aspect, the mixing or controllable valve assembly 45 can be
arranged to supply the low pressure and high pressure bleed air to
the turbo air cycle machine 38. Non-limiting examples of the mixing
or controllable valve assembly 45 can include a turbo-ejector
proportional assembly, wherein the high pressure bleed port 36
entrains at least a portion of the low pressure bleed air of the
low pressure bleed port 34, or "pulls" air from the low pressure
bleed port 34, and provides the mixed, combined, or entrained air
to the turbo air cycle machine 38. Stated another way, the
turbo-ejector proportional assembly can simultaneously supply at
least a portion of the low pressure bleed air to the compressor
section 42 and entrain another portion of the low pressure bleed
air with the high pressure bleed air. Embodiments of the disclosure
can supply any ratio of low pressure bleed air to high pressure
bleed air, such as up to 100% of a first bleed air, and 0% of the
other bleed air. In another example embodiment of the disclosure,
the supply ratio of the low pressure bleed air and high pressure
bleed air can be selected to never go below, or alternatively, to
never exceed, a predetermined ratio. For example, the low pressure
bleed port 34 of the gas turbine engine 12 can be fluidly coupled
with the compressor 42 of the turbo air cycle machine 38 by way of
a first controllable valve 46. Additionally, the high pressure
bleed port 36 of the gas turbine engine 12 can be directly fluidly
coupled with the turbine 40 of the turbo air cycle machine 38 by
way of a second controllable valve 50. Non-limiting examples of the
first or second controllable valves 46, 50 can include a step-wise
valve or continuous valve. The step-wise valve can operate in
response to, related to, or as a function of the aircraft flight
phase or the rotational speed of the gas turbine engine 12. For
example, the rotational speed of the gas turbine engine 12 can
include predetermined speed ranges or speed steps.
[0018] The low pressure bleed air provided by the low pressure
bleed port 34 can be further provided to the turbine 40, downstream
of the respective first and second valves 46, 50, wherein a fluid
coupling providing the low pressure bleed air to the turbine 40 can
include a check valve 52 biased in the direction from the low
pressure bleed port 34 toward the high pressure bleed port 36 or
the turbine 40 of the turbo air cycle machine 38. In this sense,
the check valve 52 is configured such that fluid can only flow from
the low pressure bleed port 34 to the high pressure bleed port 36
or the turbine 40 of the turbo air cycle machine 38.
[0019] Embodiments of the disclosure can be included wherein the
check valve 52 is selected or configured to provide fluid traversal
from the low pressure bleed port 34 toward the high pressure bleed
port 36 under defined or respective pressures of the flow in the
respective the low pressure bleed port 34 toward the high pressure
bleed port 36. For example, the check valve 52 can be selected or
configured to only provide fluid traversal, as shown, the air
pressure of the high pressure bleed port 36 is lower or less than
the air pressure of the low pressure bleed port 34. In another
example, the check valve 52 can be selected or configured such that
the valve 52 closes, or self-actuates to a closed position under
back pressure, that is when the pressure of the high pressure bleed
port 36 is higher or greater than the air pressure of the low
pressure bleed port 36. Alternatively, embodiments of the
disclosure can include a check valve 52 or turbo-ejector
proportional assembly that is controllable to provide selective
fluid traversal from the low pressure bleed port 34 toward the high
pressure bleed port 36.
[0020] The compressor 42 of the turbo air cycle machine 38 can
include a compressor output 54, and the turbine 40 can include a
turbine output 56. The compressor output 54 and the turbine output
56 are fluidly combined downstream of the turbo air cycle machine
38. The flow mixer is arranged to fluidly combine the compressor
output 54 and the turbine output 56 to a common mixed flow that is
supplied to the bleed air inlet 49 of the ECS 48. In this sense,
the bleed air system 20 preconditions the bleed air before the
bleed air is received by the bleed air inlet 49 of the ECS 48.
[0021] In the illustrated embodiment of the flow mixer, the
turbo-ejector 44 pressurizes the turbine output 56 as it traverses
a narrow portion 58, or "throat" of the turbo-ejector 44, and
fluidly injects the compressor output 54 into the narrow portion 58
of the turbo-ejector 44. The injection of the compressor output 54
into the pressurized turbine output 56 at the narrow portion 58 of
the turbo-ejector 44 fluidly combines the respective outputs 54,
56. The turbo-ejector 44 or combined outputs 54, 56 are fluidly
coupled downstream with the ECS 48 at a bleed air inlet 49.
Embodiments of the disclosure can be included wherein the
compressor output 54, the turbine output 56, or the turbo-ejector
44 (e.g. downstream from the narrow portion 58) can include a set
of sensors 28.
[0022] The turbo-ejector 44, sometimes referred to as an "ejector
pump" or an "ejector valve," works by injecting air from a higher
pressure source into a nozzle at the input end of a venturi
restriction, into which a lower pressure air source is also fed.
Air from the higher pressure source is emitted downstream into the
lower pressure flow at high velocity. Friction caused by the
adjacency of the airstreams causes the lower pressure air to be
accelerated ("entrained") and drawn through the venturi
restriction. As the higher pressure air ejected into the lower
pressure airstream expands toward the lower pressure of the low
pressure air source, the velocity increases, further accelerating
the flow of the combined or mixed airflow. As the lower pressure
air flow is accelerated by its entrainment by the higher pressure
source, the temperature and pressure of the low pressure source are
reduced, resulting in more energy to be extracted or "recovered"
from the turbine output. Non-limiting embodiments of the disclosure
can be included wherein the high pressure air source is at a higher
or greater temperature than the low pressure air source. However,
in alternative embodiments of the disclosure, the entrainment and
mixing process can occur without the high pressure air source
having a higher or greater temperature than the low pressure air
source. The above-described embodiments are application to the
turbo-ejector 44 illustrated downstream of the turbo air cycle
machine 38, as well as to the turbo-ejector embodiment of the
proportional mixing assembly 45.
[0023] The aircraft 10 or bleed air system 20 can also include a
controller module 60 having a processor 62 and memory 64. The
controller module 60 or processor 62 can be operably or
communicatively coupled to the bleed air system 20, including its
sensors 28, the first valve 46, the second valve 50, and the ECS
48. The controller module 60 or processor 62 can further be
operably or communicatively coupled with the sensors 28 dispersed
along the fluid couplings of the bleed air system 20. The memory 64
can include random access memory (RAM), read-only memory (ROM),
flash memory, or one or more different types of portable electronic
memory, such as discs, DVDs, CD-ROMs, etc., or any suitable
combination of these types of memory. The controller module 60 or
processor 62 can further be configured to run any suitable
programs. Non-limiting embodiments of the disclosure can be
included wherein, for example, the controller module 60 or
processor 62 can also be connected with other controllers,
processors, or systems of the aircraft 10, or can be included as
part of or a subcomponent of another controller, processor, or
system of the aircraft 10.
[0024] A computer searchable database of information can be stored
in the memory 64 and accessible by the controller module 60 or
processor 62. The controller module 60 or processor 62 can run a
set of executable instructions to display the database or access
the database. Alternatively, the controller module 60 or processor
62 can be operably coupled to a database of information. For
example, such a database can be stored on an alternative computer
or controller. It will be understood that the database can be any
suitable database, including a single database having multiple sets
of data, multiple discrete databases linked together, or even a
simple table of data. It is contemplated that the database can
incorporate a number of databases or that the database can actually
be a number of separate databases. The database can store data that
can include, among other things, historical data related to the
reference value for the sensor outputs, as well as historical bleed
air system 20 data for the aircraft 10 and related to a fleet of
aircraft. The database can also include reference values including
historic values or aggregated values.
[0025] During gas turbine engine 12 operation, the bleed air system
20 supplies a low pressure bleed airflow 66 along the low pressure
bleed port 34 and a high pressure bleed airflow 68 along the high
pressure bleed port 36, as previously explained. The high pressure
bleed airflow 68 is delivered to the turbine 40 of the turbo air
cycle machine 38, which in turn interacts with the turbine to drive
the rotation of the turbine 40. The high pressure bleed airflow 68
exits the turbine section 40 at the turbine output 56 as a turbine
output airflow 70. A first portion of the low pressure bleed
airflow 66 can be delivered to the compressor 42 of the turbo air
cycle machine 38, and a second portion of the low pressure bleed
airflow 66 can be delivered to the turbine 40 of the machine 38,
depending on the operation of the check valve 52 or turbo-ejector
proportional assembly, or the respective airflows 66, 68 of the
respective low pressure bleed port 34 and high pressure bleed port
36, as explained herein. For example, embodiments of the disclosure
can include operations wherein the airflow delivered to the turbine
40 can include entirely low pressure bleed airflow 66, no low
pressure bleed airflow 66, or a portion therebetween. The second
portion of the low pressure bleed airflow 66 can also be utilize to
drive the rotation of the turbine 40.
[0026] The first portion of the low pressure bleed airflow 66 can
be compressed by the rotation of the compressor 42, which is
rotatably coupled with the turbine 40. The compressed low pressure
bleed airflow 66 exits the compressor 42 at the compressor output
54 as a compressor output airflow 72. The turbine output airflow 70
and the compressor output airflow 72 are combined in the
turbo-ejector 44 to form a combined airflow stream 74, which is
further provided to the ECS 48. In this sense, the combined airflow
stream 74 can be expressed as a composition or a ratio of the low
pressure and high pressure bleed airflow 66, 68, or a composition
of a ratio of the turbine and compressor output airflows 70,
72.
[0027] The compression of the low pressure airflow 66, by the
compressor 42, generates a higher pressure and higher temperature
compressor output airflow 72, compared with the low pressure
airflow 66. Additionally, the airflows received by the turbine 40,
that is, the high pressure airflow 68 and selective low pressure
airflow 66 via the check valve 52 or turbo-ejector proportional
assembly, generates a lower pressure and a lower temperature
turbine output airflow 70, compared with the turbine 40 input
airflows 66, 68. In this sense, the compressor 42 outputs or emits
a hotter and higher pressure airflow 72, while the turbine 40
outputs or emits a cooler and lower pressure airflow 70, compared
with the relative input airflows 66, 68.
[0028] The controller module 60 or processor 62 can be configured
to operably receive a bleed air demand, generated by, for example,
the ECS 48. The bleed air demand can be provided to the controller
module 60 or processor 62 by way of a bleed air demand signal 76,
which can include bleed air demand characteristics included, but
not limited to, flow rate, temperature, or pressure. In response to
the bleed air demand signal 76, the controller module 60 or
processor 62 can operably supply proportional amounts of the low
pressure bleed airflow 66 and high pressure bleed airflow 68 to the
turbo air cycle machine 38. The proportionality of the low pressure
and high pressure bleed airflows 66, 68 can be controlled by way of
the respective first or second controllable valves 46, 50, and by
selective operation of the check valve 52 or turbo-ejector
proportional assembly.
[0029] The proportional supplying of the low pressure and high
pressure bleed airflows 66, 68 can be directly or geometrically
proportional to the turbine output airflow 70 and compressor output
airflow 72, or the turbine air cycle machine 38 operations. The
turbine output airflow 70 and compressor output airflow 72 are
combined downstream of the turbo air cycle machine 38, and the
combined airflow stream 74 is provided to the ECS 48. In one
non-limiting example, the compressor output airflow 72 can drive
the turbine output airflow 70 into the narrow portion 58 and mix
under sonic conditions. The mixed flow pressure will recover
statically through the combined airflow stream 74 to output the
turbo-ejector 44 at desired conditions. In this sense, the combined
airflow stream 74 is conditioned by way of operation of the bleed
air system 20, controllable valves 46, 50, check valve 52,
turbo-ejector proportional assembly, turbo air cycle machine 38,
the combining of the turbine output airflow 70 and the compressor
output airflow 72, or any combination thereof, to meet the ECS 48
demand for bleed air.
[0030] One of the controller module 60 or processor 62 can include
all or a portion of a computer program having an executable
instruction set for determining the bleed air demand of the ECS 48,
proportionally supplying the low pressure or high pressure bleed
airflows 66, 68, operating the controllable valves 46, 50, the
check valve's 52 or turbo-ejector proportional assembly's operation
in response to the respective high pressure and low pressure
airflows 66, 68, or a combination thereof. Regardless of whether
the controller module 60 or processor 62 controls the operation of
the bleed air system 20, the program can include a computer program
product that can include machine-readable media for carrying or
having machine-executable instructions or data structures stored
thereon. Such machine-readable media can be any available media,
which can be accessed by a general purpose or special purpose
computer or other machine with a processor. Generally, such a
computer program can include routines, programs, objects,
components, data structures, and the like, that have the technical
effect of performing particular tasks or implementing particular
abstract data types. Machine-executable instructions, associated
data structures, and programs represent examples of program code
for executing the exchange of information as disclosed herein.
Machine-executable instructions can include, for example,
instructions and data, which cause a general-purpose computer,
special purpose computer, or special purpose processing machine to
perform a certain function or group of functions.
[0031] While the bleed air characteristics of the low pressure or
high pressure bleed airflows 66, 68 can remain relatively
consistent or stable during a cruise portion of a flight by the
aircraft 10, varying aircraft 10 or flight characteristics, such as
altitude, speed, heading, solar cycle, or geographic aircraft
location can produce inconsistent airflows 66, 68 in the bleed air
system 20. Thus, the controller module 60 or processor 62 can also
be configured to operate the bleed air system 20, as explained
herein, in response to receiving a set of sensor input values
received by the sensors 28 dispersed along the fluid couplings of
the bleed air system 20. For example, the controller module 60 or
processor 62 can include predetermined, known, expected, estimated,
or calculated values for the set of airflows 66, 68, 70, 72, 74
traversing the bleed air system 20. In response to varying aircraft
10 or flight characteristics, the controller module 60 or processor
62 can alter the proportional supplying of the low pressure or high
pressure bleed airflows 66, 68 in order to meet the bleed air
demand for the ECS 48. Alternatively, the memory 64 can include a
database or lookup table such that a proportional supplying values
related to the low pressure or high pressure bleed airflows 66, 68
can be determined in response to the controller module 60 receiving
a set or subset of sensor 28 readings, measurements, or the
like.
[0032] While sensors 28 are described as "sensing," "measuring," or
"reading" respective temperatures, flow rates, or pressures, the
controller module 60 or processor 62 can be configured to sense,
measure, estimate, calculate, determine, or monitor the sensor 28
outputs, such that the controller module 60 or processor 62
interprets a value representative or indicative of the respective
temperature, flow rate, pressure, or combination thereof.
Additionally, sensors 28 can be included proximate to, or integral
with additional components not previously demonstrated. For
example, embodiments of the disclosure can include sensors 28
located to sense the combined airflow stream 74, or can include
sensors 28 located within the narrow portion 58, or "throat" of the
turbo-ejector 44.
[0033] In one non-limiting example of responsive operation, if the
high pressure bleed airflow 68 received by the high pressure bleed
port 36 includes a higher than expected pressure, or a higher than
expected temperature, as sensed by a sensor 28, the controller
module 60 or processor 62 can operate the bleed air system 20 to
partially close the second valve 50. In another non-limiting
example of responsive operation, if the low pressure bleed airflow
66 received by the low pressure bleed port 34 includes a lower than
expected pressure, or a lower than expected temperature, as sensed
by a sensor 28, the controller module 60 or processor 62 can
operate the bleed air system 20 partially open the second valve 50,
which increases the high pressure bleed airflow 68. The increase in
high pressure bleed airflow 68, in turn, increases the rotation of
the turbine 40, increasing the compression of the compressor 42.
The increase in compression of the compressor 42 raises the
pressure and temperature of the compressor output airflow 70.
[0034] Embodiments of the disclosure can be included wherein the
controller module 60 or processor 62 can be configured to operate
the bleed air system 20 to account for sensor 28 measurements in
the set or a subset of the airflows 66, 68, 70, 72, 74.
[0035] In another embodiment of the disclosure, the bleed air
system 20 can operate without feedback inputs, that is, without the
controller module 60 or processor 62 receiving sensed information
from the sensors 28. In this alternative configuration, the
controller module 60 or processor 62 can be configured to operate
the first or second valves 46, 50, and the like based on a
step-wise operation of the aircraft 10, such as the aircraft 10
flight phases.
[0036] In one non-limiting example configuration of the bleed air
system 20, wherein the ambient air outside of the aircraft 10 or
gas turbine engine 12 has an air pressure of 2.72 pounds per square
inch, absolute (psiA) and a temperature of -69.7 degrees Fahrenheit
(F), the low pressure bleed airflow can include a pressure of 17.87
psi, gage (psiG) and a temperature of 287.09 degrees F., while high
pressure bleed airflow can include a pressure of 57.34 psiG and a
temperature of 618.44 degrees. In this example, a ratio of low
pressure bleed airflow 66 to high pressure bleed airflow 68 can be
53.77% to 46.23%. This ratio can operate the turbo air cycle
machine 38 to produce a turbine output airflow 70 having a pressure
of 34.91 psiG and a temperature of 182.35 degrees F., while the
compressor output airflow 72 can include a pressure of 67.9 psiG
and a temperature of 682.59 degrees F. The turbo-ejector 44 can be
configured to combine the turbine output airflow 70 and the
compressor output airflow 72 to provide a combined airflow stream
74 including a pressure of 47.92 psiG and a temperature of 454.27
degrees F. The aforementioned example configuration and values are
merely one non-limiting example of the bleed air system 20
described herein.
[0037] FIG. 4 illustrates a flow chart demonstrating a non-limiting
example method 100 of providing bleed air to the ECS 48 of an
aircraft 10 using a gas turbine gas turbine engine 12. The method
100 begins by determining a bleed air demand for the ECS 110. The
determining the bleed air demand for the ECS 110 can include
determining at least one of an air pressure, an air temperature, or
a flow rate demand for the ECS 48, or a combination thereof. The
bleed air demand can be a function of at least one of the number of
aircraft 10 passengers, aircraft 10 flight phase, or operational
subsystems of the ECS 48. The bleed air demand can be determined by
the ECS 48, the controller module 60, or the processor 62, based on
the bleed air demand signal 76.
[0038] Next, the controller module 60 or the processor 62 operably
controls the proportional mixing valve assembly 45 to
proportionally supply the low pressure and high pressure bleed air
120 such that turbo air cycle machine 38 emits a cooled air stream
from the turbine 40 and a compressed air stream from the compressor
42. Embodiments of the disclosure can include, but are not limited
to, supplying up to 100% of the combined airflow stream 74 of one
of the low pressure or high pressure bleed airflow 66, 68, and 0%
of the corresponding other of the low pressure or high pressure
bleed airflow 66, 68. Another example embodiment of the disclosure
can include, but is not limited to, step-wise proportionally
supplying the low pressure and high pressure bleed airflows 66, 68,
wherein the step-wise supplying is related to, or is a function of
the aircraft 10 flight phase or rotational speed of the gas turbine
engine 12. The proportionally supplying of the bleed air 120 can
include continuously proportionally supplying the bleed air 120,
that is, repeatedly altering the proportional supplying of the low
pressure and high pressure bleed airflows 66, 68 over a period of
time, or indefinitely during the flight of the aircraft 10.
[0039] The method 100 continues by combining the cooled air stream
and the compressed air stream 130 to form a conditioned or combined
airflow stream 74. The proportional supplying the low pressure and
the high pressure bleed air 120 is controlled by the controller
module 60 or processor 62 such that the combined airflow stream 74
meets the determined bleed air demand for the ECS.
[0040] The sequence depicted is for illustrative purposes only and
is not meant to limit the method 100 in any way as it is understood
that the portions of the method can proceed in a different logical
order, additional or intervening portions can be included, or
described portions of the method can be divided into multiple
portions, or described portions of the method can be omitted
without detracting from the described method.
[0041] Many other possible embodiments and configurations in
addition to that shown in the above figures are contemplated by the
present disclosure. For example, embodiments of the disclosure can
be included wherein the second valve 50 could be replaced with a
bleed ejector or mixing valve also coupled with the low pressure
bleed port 34. In another non-limiting example, the turbo-ejector
44, the compressor output 54, or the turbine output 56 can be
configured to prevent backflow from downstream components from
entering the turbo air cycle machine 38. In yet another
non-limiting example embodiment of the disclosure, the check valve
52 or turbo-ejector proportional assembly can include, or can be
replaced by a third controllable valve, and controlled by the
controller module 60 as explained herein, to operate or effect a
ratio of low pressure bleed airflow 66 and high pressure bleed
airflow 68 supplied to the turbine 40. Additionally, the design and
placement of the various components such as valves, pumps, or
conduits can be rearranged such that a number of different in-line
configurations could be realized.
[0042] The embodiments disclosed herein provide a method and
aircraft for providing bleed air to an environmental control
system. The technical effect is that the above described
embodiments enable the preconditioning of bleed air received from a
gas turbine engine such that the conditioning and combining of the
bleed air is selected to meet a bleed air demand for the
environmental control system. One advantage that can be realized in
the above embodiments is that the above described embodiments have
superior bleed air conditioning for the ECS without wasting excess
heat, compared with traditional pre-cooler heat exchanger systems.
Another advantage that can be realized is that by eliminating the
waste of excess heat, the system can further reduce bleed
extraction from the engine related to the wasted heat. By reducing
bleed extraction, the engine operates with improved efficiency,
yielding fuel cost savings and increasing operable flight range for
the aircraft.
[0043] Yet another advantage that can be realized by the above
embodiments is that the bleed air system can provide variable bleed
air conditioning for the ECS. The variable bleed air can meet a
variable demand for bleed air in the ECS due to a variable ECS
load, for example, as subsystems are operated or cease to
operate.
[0044] To the extent not already described, the different features
and structures of the various embodiments can be used in
combination with each other as desired. That one feature cannot be
illustrated in all of the embodiments is not meant to be construed
that it cannot be, but is done for brevity of description. Thus,
the various features of the different embodiments can be mixed and
matched as desired to form new embodiments, whether or not the new
embodiments are expressly described. Moreover, while "a set of"
various elements have been described, it will be understood that "a
set" can include any number of the respective elements, including
only one element. Combinations or permutations of features
described herein are covered by this disclosure.
[0045] This written description uses examples to disclose
embodiments of the invention, including the best mode, and also to
enable any person skilled in the art to practice embodiments of the
invention, including making and using any devices or systems and
performing any incorporated methods. The patentable scope of the
invention is defined by the claims, and can include other examples
that occur to those skilled in the art. Such other examples are
intended to be within the scope of the claims if they have
structural elements that do not differ from the literal language of
the claims, or if they include equivalent structural elements with
insubstantial differences from the literal languages of the
claims.
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