U.S. patent application number 11/734677 was filed with the patent office on 2008-05-22 for servo-controlled variable geometry ejector pump.
This patent application is currently assigned to HONEYWELL INTERNATIONAL, INC.. Invention is credited to Paul W. Banta, John A. Vasquez.
Application Number | 20080118371 11/734677 |
Document ID | / |
Family ID | 39015796 |
Filed Date | 2008-05-22 |
United States Patent
Application |
20080118371 |
Kind Code |
A1 |
Vasquez; John A. ; et
al. |
May 22, 2008 |
SERVO-CONTROLLED VARIABLE GEOMETRY EJECTOR PUMP
Abstract
A variable geometry ejector pump is configured to receive
pressurized fluid from one or more pressurized fluid sources and to
control fluid pressure and temperature down stream of the pump to a
variety of pressure and temperature values. The variable geometry
ejector pump includes a primary inlet, a secondary inlet, a
variable geometry ejector, an ejector valve, an actuator, a mixing
section, a diffuser section, and an actuator control mechanism. The
actuator control mechanism is adapted to receive one or more
control signals, and is operable, in response to the control
signals, to control the actuator, to thereby control fluid pressure
and temperature down stream of the pump.
Inventors: |
Vasquez; John A.; (Chandler,
AZ) ; Banta; Paul W.; (Phoenix, AZ) |
Correspondence
Address: |
HONEYWELL INTERNATIONAL INC.
101 COLUMBIA ROAD, P O BOX 2245
MORRISTOWN
NJ
07962-2245
US
|
Assignee: |
HONEYWELL INTERNATIONAL,
INC.
Morristown
NJ
|
Family ID: |
39015796 |
Appl. No.: |
11/734677 |
Filed: |
April 12, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60859342 |
Nov 16, 2006 |
|
|
|
Current U.S.
Class: |
417/77 ;
239/533.5 |
Current CPC
Class: |
F02C 6/08 20130101; F04F
5/461 20130101; F05D 2260/601 20130101; F02C 3/32 20130101; F04F
5/54 20130101; F04D 13/12 20130101 |
Class at
Publication: |
417/77 ;
239/533.5 |
International
Class: |
F04B 23/04 20060101
F04B023/04 |
Claims
1. A variable geometry ejector pump, comprising: a primary inlet; a
secondary inlet; a variable geometry ejector including at least a
flow passage and an outlet nozzle, the variable geometry ejector
flow passage fluidly communicating the primary fluid inlet port
with the variable geometry ejector outlet nozzle; an ejector valve
disposed at least partially within the variable geometry ejector
flow passage and movable therein to control fluid flow from the
primary fluid inlet through the variable geometry ejector outlet
nozzle; a mixing section in fluid communication with the secondary
inlet and the variable geometry ejector outlet nozzle; a diffuser
disposed downstream of, and in fluid communication with, the mixing
section; an actuator coupled to the ejector valve and further
coupled to receive position commands, the actuator responsive to
the position commands to controllably move the ejector valve; and
an actuator control mechanism coupled to the actuator and adapted
to receive one or more control signals, the actuator control unit
operable, in response to the one or more control signals, to supply
the position commands to the actuator.
2. The variable geometry ejector pump of claim 1, wherein the
position commands supplied from the actuator control mechanism are
pneumatic commands.
3. The variable geometry ejector pump of claim 2, wherein: the
actuator is responsive to a differential pneumatic pressure to
thereby controllably move the ejector valve; and the actuator
control mechanism controls the differential pressure.
4. The variable geometry ejector pump of claim 3, further
comprising: a feedback conduit including an inlet port and an
outlet port, the feedback conduit inlet port in fluid communication
with the diffuser, the feedback conduit outlet port in fluid
communication with the actuator, wherein the actuator control
mechanism is disposed at least partially within the feedback
conduit and is operable, in response to the one or more control
signals, to control the differential pressure via the feedback
conduit.
5. The variable geometry ejector pump of claim 4, wherein the
actuator comprises: an actuator enclosure including a control port
and a vent port, the actuator enclosure control port in fluid
communication with the feedback conduit outlet port, the actuator
enclosure vent port in fluid communication with an ambient
environment; a piston coupled to the valve and slidably disposed
within the actuator enclosure between the control port and the vent
port; and a spring disposed within the actuator enclosure and
configured to supply a bias force to the piston that biases the
valve away from the variable geometry ejector outlet nozzle.
6. The variable geometry ejector pump of claim 4, further
comprising: one or more sensors disposed at least partially within,
or downstream of, the diffuser section and operable to supply one
or more sensor signals; and a control unit coupled to receive the
one or more sensor signals and operable, in response thereto, to
selectively supply the one or more control signals to the feedback
control mechanism.
7. The variable geometry ejector pump of claim 1, further
comprising: a control unit operable to selectively supply the one
or more control signals to the actuator control mechanism.
8. The variable geometry ejector pump of claim 7, further
comprising: one or more sensors disposed at least partially within,
or downstream of, the diffuser section and operable to supply one
or more sensor signals to the control unit.
9. The variable geometry ejector pump of claim 8, wherein the
control unit is responsive to the one or more sensor signals to
selectively supply the one or more control signals.
10. The variable geometry ejector pump of claim 8, wherein the one
or more sensors comprise one or more temperature sensors.
11. The variable geometry ejector pump of claim 1, further
comprising: one or more sensors disposed at least partially within,
or downstream of, the diffuser section and operable to supply the
one or more control signals to the feedback control mechanism.
12. The variable geometry ejector pump of claim 11, wherein the one
or more sensors comprise one or more temperature sensors.
13. The variable geometry ejector pump of claim 11, wherein the one
or more sensors comprise one or more pressure sensors.
14. The variable geometry ejector pump of claim 1, wherein the one
or more sensors comprise one or more temperature sensors and one or
more pressure sensors.
15. A variable geometry ejector pump, comprising: a primary inlet;
a secondary inlet; a variable geometry ejector including at least a
flow passage and an outlet nozzle, the variable geometry ejector
flow passage fluidly communicating the primary fluid inlet port
with the variable geometry ejector outlet nozzle; an ejector valve
disposed at least partially within the variable geometry ejector
flow passage and movable therein to control fluid flow from the
primary fluid inlet through the variable geometry ejector outlet
nozzle; a mixing section in fluid communication with the secondary
inlet and the variable geometry ejector outlet nozzle; a diffuser
disposed downstream of, and in fluid communication with, the mixing
section; an actuator coupled to the ejector valve responsive to a
differential pneumatic pressure to thereby controllably move the
ejector valve; and an actuator control mechanism coupled to the
actuator and adapted to receive one or more control signals, the
actuator control unit operable, in response to the one or more
control signals, to control the differential pressure.
16. The variable geometry ejector pump of claim 15, wherein the
actuator comprises: an actuator enclosure including at least a
control port and a vent port, the actuator enclosure control port
in fluid communication with the actuator control mechanism, the
actuator enclosure vent port in fluid communication with an ambient
environment; a piston coupled to the valve and slidably disposed
within the actuator enclosure between the control port and the vent
port; and a spring disposed within the actuator enclosure and
configured to supply a bias force to the piston that biases the
valve away from the variable geometry ejector outlet nozzle.
17. The variable geometry ejector pump of claim 15, wherein the
actuator comprises: an actuator enclosure including a control port
and a vent port, the control port and vent port each in fluid
communication with the actuator control mechanism; a piston coupled
to the valve and slidably disposed within the actuator enclosure
between the control port and the vent port; and a spring disposed
within the actuator enclosure and configured to supply a bias force
to the piston that biases the valve away from the variable geometry
ejector outlet nozzle.
18. The variable geometry ejector pump of claim 15, further
comprising: one or more sensors disposed at least partially within,
or downstream of, the diffuser section and operable to supply one
or more sensor signals; and a control unit coupled to receive the
one or more sensor signals and operable, in response thereto, to
selectively supply the one or more control signals to the feedback
control mechanism.
19. The variable geometry ejector pump of claim 15, further
comprising: one or more sensors disposed at least partially within,
or downstream of, the diffuser section and operable to supply the
one or more control signals to the feedback control mechanism.
20. The variable geometry ejector pump of claim 15, further
comprising: a control unit operable to selectively supply the one
or more control signals to the actuator control mechanism.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/859,342, filed Nov. 16, 2006.
TECHNICAL FIELD
[0002] The present invention relates to ejector pumps and, more
particularly, to a variable geometry ejector pump that is
configured to control downstream pressure and temperature to a
variety of pressure and temperature values.
BACKGROUND
[0003] A gas turbine engine may be used to supply power to various
types of vehicles and systems. For example, gas turbine engines may
be used to supply propulsion power to an aircraft. Many gas turbine
engines include at least three major sections, a compressor
section, a combustor section, and a turbine section. The compressor
section, which may include two or more compressor stages, receives
a flow of intake air and raises the pressure of this air to a
relatively high level. The compressed air from the compressor
section then enters the combustor section, where a ring of fuel
nozzles injects a steady stream of fuel. The injected fuel is
ignited by a burner, which significantly increases the energy of
the compressed air.
[0004] The high-energy compressed air from the combustor section
then flows into and through the turbine section, causing
rotationally mounted turbine blades to rotate and generate energy.
The air exiting the turbine section is then exhausted from the
engine. Similar to the compressor section, in a multi-spool engine
the turbine section may include a plurality of turbine stages. The
energy generated in each of the turbines may be used to power other
portions of the engine.
[0005] In addition to providing propulsion power, a gas turbine
engine may also, or instead, be used to supply either, or both,
electrical and pneumatic power to the aircraft. For example, some
gas turbine engines include a bleed air port on the compressor
section. The bleed air port allows some of the compressed air from
the compressor section to be diverted away from the combustor and
turbine sections, and used for other functions such as, for
example, the aircraft environmental control system, and/or cabin
pressure control system.
[0006] Regardless of its particular end use, the bleed air is
preferably supplied at a sufficiently high pressure to provide
proper flow through the system. As noted above, bleed air is
extracted after it has been compressed, which increases the load on
the turbine engine. Therefore, extra fuel consumption may result,
and engine performance can be degraded. The engine performance
penalty may be minimized by extracting the bleed air from the
lowest compressor stage (or stages) that can supply the pressure
required by the downstream systems. The ideal solution for
performance would be to have the capability of extracting the bleed
air from the compressor stage that exactly matches the downstream
systems requirements throughout the operating envelope. Most modern
commercial aircraft turbine engines have on the order of 10-12
compressor stages. For practical considerations, typical commercial
aircraft bleed systems are limited to two discrete bleed air ports.
Moreover, many conventional bleed air systems include a heat
exchanger and a fan air valve (FAV) to limit the temperature of the
bleed air supplied to some end-use systems. These components can
increase overall system weight and, concomitantly, overall system
cost. Moreover, the heat exchanger may be mounted outside of the
aircraft and in a position that increases aerodynamic drag, which
can increase fuel consumption.
[0007] One solution to the above-mentioned drawbacks is disclosed
in U.S. Pat. No. 6,701,715 (hereinafter "the '715 patent"),
entitled "Variable Geometry Ejector for a Bleed Air System Using
Integral Ejector Exit Pressure Feedback," which is assigned to the
Assignee of the instant invention. Once weakness of the solution
disclosed in the '715 patent is that the ejector can only control
bleed air pressure downstream of the ejector to a single
pressure.
[0008] Hence, there is a need for a device that may be used in a
bleed air system that can be used to more efficiently control the
bleed air extracted from the engine by mixing air from separate
bleed air ports, decreases overall system weight and cost and/or
does not present aerodynamic drag and/or can control downstream
bleed air pressure to a variety of pressures and temperatures using
a variety of parameters/signals to determine the optimum outlet
conditions.
BRIEF SUMMARY
[0009] In one embodiment, and by way of example only, a variable
geometry ejector pump includes a primary inlet, a secondary inlet,
a variable geometry ejector, an ejector valve, a mixing section, a
diffuser, an actuator, and an actuator control unit. The variable
geometry ejector includes at least a flow passage and an outlet
nozzle. The variable geometry ejector flow passage fluidly
communicates the primary fluid inlet port with the variable
geometry ejector outlet nozzle. The ejector valve is disposed at
least partially within the variable geometry ejector flow passage
and is movable therein to control fluid flow from the primary fluid
inlet through the variable geometry ejector outlet nozzle. The
mixing section is in fluid communication with the secondary inlet
and the variable geometry ejector outlet nozzle. The diffuser is
disposed downstream of, and is in fluid communication with, the
mixing section. The actuator is coupled to the ejector valve and is
further coupled to receive position commands. The actuator is
responsive to the position commands to controllably move the
ejector valve. The actuator control mechanism is coupled to the
actuator and is adapted to receive one or more control signals. The
actuator control unit is operable, in response to the one or more
control signals, to supply the position commands to the
actuator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention will hereinafter be described in
conjunction with the following drawing figures, wherein like
numerals denote like elements, and wherein:
[0011] FIG. 1 is a simplified representation of a bleed air system
1000 according to an exemplary embodiment of the present invention;
and
[0012] FIGS. 2 and 3 are simplified representations of exemplary
embodiments of variable geometry ejector pumps that may be used to
implement the system of FIG. 1.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
[0013] The following detailed description is merely exemplary in
nature and is not intended to limit the invention or the
application and uses of the invention. Furthermore, there is no
intention to be bound by any theory presented in the preceding
background or the following detailed description. In this regard,
although the present embodiment is, for ease of explanation,
depicted and described as being implemented in an aircraft gas
turbine engine bleed air system, it will be appreciated that it can
be implemented in various other systems and environments.
[0014] Turning now to FIG. 1, a simplified representation of a
bleed air system 1000 that may be used to supply bleed air to, for
example, an environmental control system, is depicted. The system
1000 includes a gas turbine engine 100, a valve stage 200, and a
variable geometry ejector pump 300. The gas turbine engine 100
includes a compressor 102, a combustor 104, and a turbine 106, all
disposed within a case 110. The compressor 102, which is preferably
a multi-stage compressor, raises the pressure of air directed into
it via an air inlet 112. The compressed air is then directed into
the combustor 104, where it is mixed with fuel supplied from a fuel
source (not shown). The fuel/air mixture is ignited using one or
more igniters 114, and high energy combusted air is then directed
into the turbine 106. The combusted air expands through the turbine
106, causing it to rotate. The air is then exhausted via an exhaust
gas outlet 116. As the turbine 106 rotates, it drives, via a shaft
118 coupled to the turbine 106, equipment in, or coupled to, the
engine 100. For example, in the depicted embodiment the turbine 106
drives the multi-stage compressor 102 and a generator 120 coupled
to the engine 100. It will be appreciated that the gas turbine
engine 100 is not limited to the configuration depicted in FIG. 1
and described herein, but could be any one of numerous types of gas
turbine engines, such as a turbofan gas turbine engine that
includes multiple turbines, multiple spools, multiple compressors,
and a fan. Moreover, a gas turbine engine need not be the source of
the bleed air that is supplied to the remainder of the system
1000.
[0015] Preferably, a plurality of bleed air ducts 122 are coupled
between the multi-stage compressor 102 and the valve stage 200. The
bleed air ducts 122, which in the depicted embodiment include a
low-pressure stage duct 122-1, a mid-pressure stage duct 122-2, and
a high-pressure stage duct 122-3, are each in fluid communication
with different stages in the multi-stage compressor 102.
Preferably, as each duct nomenclature denotes herein, the
low-pressure stage duct 122-1 is in fluid communication with a
relatively low-pressure compressor stage, the mid-pressure stage
duct 122-2 is in fluid communication with a relatively mid-pressure
compressor stage, and the high-pressure stage duct 122-3 is in
fluid communication with a relatively high-pressure compressor
stage. Preferably, the low-pressure stage is chosen such that its
outlet temperature will not exceed a maximum value as defined by
the downstream system, the mid-pressure stage is chosen to optimize
the efficiency of the bleed air extraction over the operating
envelope, and the high-pressure stage is chosen such that its
minimum outlet pressure is sufficiently high to supply the
downstream systems when the engine is operated at low power and/or
high altitude. In one particular embodiment, the low-pressure
stage, mid-pressure stage, and high-pressure stage are a third
stage, a fourth stage, and a tenth stage, respectively. It will
additionally be appreciated that the system 1000 could be
implemented with more than three bleed air ducts 122 coupled to
more than three different compressor stages, if needed or
desired.
[0016] Bleed air from each of the compressor stages is supplied to
the valve stage 200. The valve stage 200 is coupled between each of
the bleed air ducts 122 and the variable geometry ejector pump 300
and, at least in the depicted embodiment, includes three inlet
ports 202 and two outlet ports 204. In particular, the valve stage
200 includes a low-pressure bleed air inlet port 202-1, a
mid-pressure bleed air inlet port 202-2, a high-pressure bleed air
inlet port 202-3, a high-pressure bleed air outlet port 204-1, and
a low-pressure bleed air outlet port 204-2. The valve stage 200 may
be implemented as a multi-port valve, a plurality of independently
controlled valves, or various combinations thereof. It will
additionally be appreciated that in some embodiments, the system
1000 may be implemented without the valves stage 200.
[0017] No matter its specific physical implementation, the valve
stage 200, if it is included in the system 1000, is configured to
selectively allow bleed air from one or more of the three bleed air
conduits 122 to flow out one or more of the bleed air outlet ports
204. In the depicted embodiment, the valve stage 200 is controlled
by a control unit 400, which is configured to supply appropriate
commands to the valve stage 200. The valve stage 200, in response
to the commands from the control unit 400, selectively allows bleed
air from one or more of the three bleed air conduits 122 to flow
out one or more of the bleed air outlet ports 204 to the variable
geometry ejector pump 300. It will be appreciated that the control
unit 400 could be implemented as a stand-alone device that is used
to control the operation of the valve stage 200 only, or one or
more other devices. It will additionally be appreciated that the
function of the control unit 400 could be implemented in another
control device such as, for example, an engine controller.
[0018] Turning to FIG. 2, a one exemplary embodiment of the
variable geometry ejector pump 300 is depicted, and will now be
described in more detail. The depicted variable geometry ejector
pump 300 includes a primary inlet 302, a secondary inlet 304, a
variable geometry ejector 306, a mixing section 308, a diffuser
310, a feedback conduit 312, and a actuator control mechanism 350.
The primary inlet 302 and the secondary inlet 304 may
simultaneously receive a flow of fluid, such as engine bleed air,
or only one of the inlets 302, 304 may receive may receive a flow
of fluid. Preferably, however, if both inlets 302, 304 are
simultaneously receiving fluid flow, the fluid having the higher
relative pressure (and thus higher relative temperature) is
supplied to the primary inlet 302 and the fluid having the lower
relative pressure (and thus lower relative temperature) is supplied
to the secondary inlet 304.
[0019] The variable geometry ejector 306 includes a flow passage
314, an outlet nozzle 316, a valve element 318, and an actuator
322. The flow passage 314 fluidly communicates the primary inlet
302 with the outlet nozzle 316. The valve element 318 is movably
disposed at least partially within the flow passage 314 and its
position controls fluid flow through the flow passage 314 and out
the outlet nozzle 316, to thereby control the flow of fluid
supplied to the primary inlet 302 into the mixing section 308.
[0020] The position of the valve element 318 is controlled by the
actuator 322, which may include a piston 324, and a bias spring
326. The piston 324 is coupled to the valve element 318 and is
disposed in an actuator enclosure 328. The bias spring 326 is
disposed between the piston 324 and the actuator enclosure 328 and
supplies a bias force to the piston 324 that biases the valve
element 318 away from the outlet nozzle 316. The actuator enclosure
328 includes a control port 332 and a vent 334. There may
additionally be a first seal 319 between the piston 324 and
actuator enclosure 328, and a second seal 321 between the valve
element 318 and the actuator enclosure 328. It will be appreciated
that actuator 322 may alternatively be implemented as an electrical
or electromechanical type of actuator.
[0021] Bleed air, or other fluid, supplied to the secondary inlet
304 is supplied to the mixing section 308, where it mixes with
fluid that may be exiting the ejector pump outlet nozzle 316. It
will be appreciated that, depending on the position of the valve
element 318, there may be no fluid exiting the ejector pump outlet
nozzle 316. Nonetheless, fluid in the mixing section 308 then flows
into and through the diffuser 310, and is supplied to one or more
bleed air loads. As FIG. 2 also depicts, a portion of the fluid
flowing through the diffuser 310 is also directed into the feedback
conduit 312.
[0022] The feedback conduit 312 includes an inlet 311 and an outlet
313. The feedback conduit inlet 311 is in fluid communication with
the diffuser 310, and the feedback conduit outlet 313 is in fluid
communication with the actuator enclosure control port 332. Thus,
the static pressure of the bleed air in the diffuser 310 may be
selectively directed to the actuator piston 324. As such, the
differential pressure across the piston 324 may be used to control
the position of the ejector pump valve element 318 and,
concomitantly, the geometry of the ejector pump outlet nozzle 316
and ejector pump exit flow. The differential pressure across the
actuator piston 324 is controlled by the actuator control mechanism
350.
[0023] The actuator control mechanism 350 is disposed, at least
partially, in the feedback conduit 312 between the feedback conduit
inlet 311 and outlet 313. The actuator control mechanism 350, as
noted above, is configured to control the position of the ejector
pump valve element 318 based on a control scheme using multiple
input signals and accounting for changing requirements. It will be
appreciated that the actuator control mechanism 350 may be
implemented using any one of numerous feedback control devices now
known or developed in the future. Preferably, however, it is
implemented using a servomechanism, such as a servo-controlled
valve.
[0024] No matter how the actuator control mechanism 350 is
specifically implemented, it is preferably configured to be
responsive to commands received from either a control unit or one
or more signals representative of pressure and or temperature
downstream of or within the variable geometry ejector pump 300. In
the depicted embodiment, the actuator control mechanism 350 is
responsive to commands received from a control unit 330. The
control unit 330 may be implemented as either a pneumatic or
electronic device, and is responsive to system inputs or commands
331 received from either a separate, non-illustrated control unit
or system, and/or one or more signals representative of fluid
pressure and temperature downstream of (or within) the ejector pump
300. The pressure and temperature signals, at least in the depicted
embodiment, are supplied from a pressure sensor 336 and a
temperature sensor 338. It will be appreciated that the valve 300
could include only one of the sensors. It will additionally be
appreciated that if the system inputs or commands 331 are supplied
from a control unit, this control unit may be the same control unit
400 that is used to control the valve stage 200, or it may be
implemented as a separate, independent control unit.
[0025] Alternatively, and as was noted above, the pressure and/or
temperature signals could be supplied directly to the actuator
control mechanism 350. This particular configuration is depicted in
FIG. 2 using dotted lines. It will additionally be appreciated that
the sensors 336, 338, rather than supplying electrical signals to
the control unit 330 or the actuator control mechanism 350, could
instead be configured as pneumatic-type sensors. In such an
embodiment, the actuator control mechanism 350 could be implemented
as a pneumatically controlled device that is responsive to
pneumatic signal variations supplied from the sensors 336, 338.
[0026] In yet another alternative embodiment, which is depicted in
FIG. 3, the ejector pump 300 is configured similar to that depicted
in FIG. 2, but the vent 334 is not in fluid communication with the
ambient environment and the actuator control mechanism 350 is not
in fluid communication with the diffuser 310. Rather, in this
embodiment, the actuator control mechanism 350 is in fluid
communication with both of the actuator enclosure ports 332,
334.
[0027] While the invention has been described with reference to a
preferred embodiment, 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 invention. In addition, many modifications may be made to
adapt to a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention.
* * * * *