U.S. patent application number 13/630205 was filed with the patent office on 2014-04-03 for multiple reservoir lubrication system.
This patent application is currently assigned to UNITED TECHNOLOGIES CORPORATION. The applicant listed for this patent is UNITED TECHNOLOGIES CORPORATION. Invention is credited to Denman H. James.
Application Number | 20140090930 13/630205 |
Document ID | / |
Family ID | 50384173 |
Filed Date | 2014-04-03 |
United States Patent
Application |
20140090930 |
Kind Code |
A1 |
James; Denman H. |
April 3, 2014 |
MULTIPLE RESERVOIR LUBRICATION SYSTEM
Abstract
A lubrication system for use with a gas turbine engine includes
a first reservoir for containing a lubricant. The first reservoir
includes a first discharge passage through which the lubricant is
flowable in a first direction. A second reservoir contains the
lubricant. The second reservoir includes a second discharge passage
through which the lubricant is flowable in a second direction. The
first direction is generally opposite to the second direction. A
first pump pumps the lubricant from the first reservoir. A second
pump pumps the lubricant from the second reservoir. A manifold
distributes the lubricant to a component. The lubricant from the
first pump and the second pump flows into the manifold and exits
the manifold through a manifold discharge.
Inventors: |
James; Denman H.; (Windsor,
CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UNITED TECHNOLOGIES CORPORATION |
Hartford |
CT |
US |
|
|
Assignee: |
UNITED TECHNOLOGIES
CORPORATION
Hartford
CT
|
Family ID: |
50384173 |
Appl. No.: |
13/630205 |
Filed: |
September 28, 2012 |
Current U.S.
Class: |
184/6.11 ;
184/6 |
Current CPC
Class: |
F01M 11/067 20130101;
F05D 2260/98 20130101; F01D 25/20 20130101 |
Class at
Publication: |
184/6.11 ;
184/6 |
International
Class: |
F01D 25/20 20060101
F01D025/20 |
Claims
1. A lubrication system for use with a gas turbine engine
comprising: a first reservoir for containing a lubricant, wherein
the first reservoir includes a first discharge passage through
which the lubricant is flowable in a first direction; a second
reservoir for containing the lubricant, wherein the second
reservoir includes a second discharge passage through which the
lubricant is flowable in a second direction, wherein the first
direction is generally opposite to the second direction; a first
pump that pumps the lubricant from the first reservoir; a second
pump that pumps the lubricant from the second reservoir; and a
manifold to distribute the lubricant to a component, wherein the
lubricant from the first pump and the second pump flows into the
manifold and exits the manifold through a manifold discharge.
2. The lubrication system as recited in claim 1 wherein the
component is a bearing.
3. The lubrication system as recited in claim 1 wherein the
component is a fan journal bearing of a gas turbine engine.
4. The lubrication system as recited in claim 1 wherein the first
direction is substantially upwardly and the second direction is
substantially downwardly.
5. The lubrication system as recited in claim 1 wherein an output
of each of the first pump and the second pump is greater than a
lubrication requirement of the component.
6. The lubrication system as recited in claim 1 wherein the
lubricant flows directly from the manifold discharge of the
manifold to the component.
7. The lubrication system as recited in claim 1 including a valve,
wherein the lubricant flows from the manifold discharge of the
manifold to the valve.
8. The lubrication system as recited in claim 7 wherein the valve
is a relief valve.
9. The lubrication system as recited in claim 8 wherein the valve
directs a portion of the lubricant to the component and a remainder
of the lubricant to at least one of the first reservoir and the
second reservoir.
10. The lubrication system as recited in claim 8 wherein the valve
closes if one of the first reservoir or the second reservoir is
empty.
11. The lubrication system as recited in claim 7 wherein the valve
is a control valve, and the lubrication system includes a sensor
associated with each of the first reservoir and the second
reservoir that detects an amount of the lubricant in each of the
first reservoir and the second reservoir, and the control valve
directs the lubricant to the one of the first reservoir and the
second reservoir if one of the sensors detects that the one of the
first reservoir and the second reservoir is depleted of the
lubricant.
12. A lubrication system for use with a gas turbine engine
comprising: a first reservoir for containing a lubricant, wherein
the first reservoir includes a first discharge passage through
which the lubricant is flowable in a first direction; a second
reservoir for containing a lubricant, wherein the second reservoir
includes a second discharge passage through which the lubricant is
flowable in a second direction, wherein the first direction is
opposite to the second direction; a first pump that pumps the
lubricant from the first reservoir; a second pump that pumps the
lubricant from the second reservoir; a manifold to distribute the
lubricant to a bearing, wherein the lubricant from the first pump
and the second pump flows into the manifold and exits the manifold
through a manifold discharge; and a valve, wherein the lubricant
flows from the manifold discharge of the manifold to the valve.
13. The lubrication system as recited in claim 12 wherein the
component is a fan journal bearing of a gas turbine engine.
14. The lubrication system as recited in claim 12 wherein the first
direction is substantially upwardly and the second direction is
substantially downwardly.
15. The lubrication system as recited in claim 12 wherein an output
of each of the first pump and the second pump is greater than a
lubrication requirement of the component.
16. The lubrication system as recited in claim 12 wherein the valve
is a relief valve.
17. The lubrication system as recited in claim 16 wherein the valve
directs a portion of the lubricant to the component and a remainder
of the lubricant to at least one of the first reservoir and the
second reservoir.
18. The lubrication system as recited in claim 16 wherein the valve
closes if one of the first reservoir or the second reservoir is
empty.
19. The lubrication system as recited in claim 16 wherein the valve
is a control valve, and the lubrication system includes a sensor
associated with each of the first reservoir and the second
reservoir that detects an amount of the lubricant in each of the
first reservoir and the second reservoir, and the control valve
directs the lubricant to the one of the first reservoir and the
second reservoir if one of the sensors detects that the one of the
first reservoir and the second reservoir is depleted of the
lubricant.
Description
BACKGROUND OF THE INVENTION
[0001] Some areas of a gas turbine engine require uninterrupted
lubrication during engine operation. Example areas are bearings,
such as rolling element bearings or journal bearings, or gears used
throughout the engine and engine accessories. Lubricant is stored
in a reservoir.
[0002] A sudden change in attitude of the engine could move the
lubricant in the reservoir, moving the lubricant away from a
discharge passage. If this occurs, there could be an interruption
in the supply of lubricant to the lubricated components.
SUMMARY OF THE INVENTION
[0003] A lubrication system for use with a gas turbine engine
according to an exemplary embodiment of this disclosure, among
other possible things includes, a first reservoir for containing a
lubricant. The first reservoir includes a first discharge passage
through which the lubricant is flowable in a first direction. A
second reservoir contains the lubricant. The second reservoir
includes a second discharge passage through which the lubricant is
flowable in a second direction. The first direction is generally
opposite to the second direction. A first pump pumps the lubricant
from the first reservoir. A second pump pumps the lubricant from
the second reservoir. A manifold distributes the lubricant to a
component. The lubricant from the first pump and the second pump
flows into the manifold and exits the manifold through a manifold
discharge.
[0004] In a further embodiment of any of the foregoing lubrication
systems, the component is a bearing.
[0005] In a further embodiment of any of the foregoing lubrication
systems, the component is a fan journal bearing of a gas turbine
engine.
[0006] In a further embodiment of any of the foregoing lubrication
systems, the first direction is substantially upwardly and the
second direction is substantially downwardly.
[0007] In a further embodiment of any of the foregoing lubrication
systems, an output of each of the first pump and the second pump is
greater than a lubrication requirement of the component.
[0008] In a further embodiment of any of the foregoing lubrication
systems, the lubricant flows directly from the manifold discharge
of the manifold to the component.
[0009] In a further embodiment of any of the foregoing lubrication
systems, includes a valve. The lubricant flows from the manifold
discharge of the manifold to the valve.
[0010] In a further embodiment of any of the foregoing lubrication
systems, the valve is a relief valve.
[0011] In a further embodiment of any of the foregoing lubrication
systems, the valve directs a portion of the lubricant to the
component and a remainder of the lubricant to at least one of the
first reservoir and the second reservoir.
[0012] In a further embodiment of any of the foregoing lubrication
systems, the valve closes if one of the first reservoir or the
second reservoir is empty.
[0013] In a further embodiment of any of the foregoing lubrication
systems, the valve is a control valve. The lubrication system
includes a sensor associated with each of the first reservoir and
the second reservoir that detects an amount of the lubricant in
each of the first reservoir and the second reservoir. The control
valve directs the lubricant to the one of the first reservoir and
the second reservoir if one of the sensors detects that the one of
the first reservoir and the second reservoir is depleted of the
lubricant.
[0014] A lubrication system for use with a gas turbine engine
according to an exemplary embodiment of this disclosure, among
other possible things includes, a first reservoir for containing a
lubricant. The first reservoir includes a first discharge passage
through which the lubricant is flowable in a first direction. A
second reservoir containing a lubricant. The second reservoir
includes a second discharge passage through which the lubricant is
flowable in a second direction. The first direction is opposite to
the second direction. A first pump pumps the lubricant from the
first reservoir. A second pump pumps the lubricant from the second
reservoir. A manifold distributes the lubricant to a bearing. The
lubricant from the first pump and the second pump flows into the
manifold and exits the manifold through a manifold discharge, and a
valve. The lubricant flows from the manifold discharge of the
manifold to the valve.
[0015] In a further embodiment of any of the foregoing lubrication
system, the component is a fan journal bearing of a gas turbine
engine.
[0016] In a further embodiment of any of the foregoing lubrication
systems, the first direction is substantially upwardly and the
second direction is substantially downwardly.
[0017] In a further embodiment of any of the foregoing lubrication
systems, an output of each of the first pump and the second pump is
greater than a lubrication requirement of the component.
[0018] In a further embodiment of any of the foregoing lubrication
systems, the valve is a relief valve.
[0019] In a further embodiment of any of the foregoing lubrication
systems, the valve directs a portion of the lubricant to the
component and a remainder of the lubricant to at least one of the
first reservoir and the second reservoir.
[0020] In a further embodiment of any of the foregoing lubrication
systems, the valve closes if one of the first reservoir or the
second reservoir is empty.
[0021] In a further embodiment of any of the foregoing lubrication
systems, the valve is a control valve. The lubrication system
includes a sensor associated with each of the first reservoir and
the second reservoir that detects an amount of the lubricant in
each of the first reservoir and the second reservoir. The control
valve directs the lubricant to the one of the first reservoir and
the second reservoir if one of the sensors detects that the one of
the first reservoir and the second reservoir is depleted of the
lubricant.
[0022] These and other features of the present invention can be
best understood from the following specification and drawings, the
following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 illustrates a schematic view of an embodiment of a
gas turbine engine; and
[0024] FIG. 2 illustrates a lubrication system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0025] FIG. 1 schematically illustrates a gas turbine engine 20.
The gas turbine engine 20 is disclosed herein as a two-spool
turbofan that generally incorporates a fan section 22, a compressor
section 24, a combustor section 26 and a turbine section 28.
Alternative engines might include an augmentor section (not shown)
among other systems or features.
[0026] Although depicted as a turbofan gas turbine engine in the
disclosed non-limiting embodiment, it should be understood that the
concepts described herein are not limited to use with turbofans as
the teachings may be applied to other types of turbine engines
including three-spool or geared turbofan architectures.
[0027] The fan section 22 drives air along a bypass flowpath B
while the compressor section 24 drives air along a core flowpath C
for compression and communication into the combustor section 26
then expansion through the turbine section 28.
[0028] The gas turbine engine 20 generally includes a low speed
spool 30 and a high speed spool 32 mounted for rotation about an
engine central longitudinal axis A relative to an engine static
structure 36 via several bearing systems 38. It should be
understood that various bearing systems 38 at various locations may
alternatively or additionally be provided. For example, the bearing
system 38 also includes fan journal bearings 38a.
[0029] The low speed spool 30 generally includes an inner shaft 40
that interconnects a fan 42, a low pressure compressor 44 and a low
pressure turbine 46. The inner shaft 40 is connected to the fan 42
through a geared architecture 48 to drive the fan 42 at a lower
speed than the low speed spool 30. The high speed spool 32 includes
an outer shaft 50 that interconnects a high pressure compressor 52
and a high pressure turbine 54.
[0030] A combustor 56 is arranged between the high pressure
compressor 52 and the high pressure turbine 54.
[0031] A mid-turbine frame 58 of the engine static structure 36 is
arranged generally between the high pressure turbine 54 and the low
pressure turbine 46. The mid-turbine frame 58 further supports
bearing systems 38 in the turbine section 28.
[0032] The inner shaft 40 and the outer shaft 50 are concentric and
rotate via bearing systems 38 about the engine central longitudinal
axis A, which is collinear with their longitudinal axes.
[0033] The core airflow C is compressed by the low pressure
compressor 44, then the high pressure compressor 52, mixed and
burned with fuel in the combustor 56, then expanded over the high
pressure turbine 54 and low pressure turbine 46. The mid-turbine
frame 58 includes airfoils 60 which are in the core airflow path.
The turbines 46, 54 rotationally drive the respective low speed
spool 30 and high speed spool 32 in response to the expansion.
[0034] The gas turbine engine 20 is in one example a high-bypass
geared aircraft engine. In a further example, the gas turbine
engine 20 bypass ratio is greater than about six (6:1) with an
example embodiment being greater than ten (10:1). The geared
architecture 48 is an epicyclic gear train (such as a planetary
gear system or other gear system) with a gear reduction ratio of
greater than about 2.3 (2.3:1). The low pressure turbine 46 has a
pressure ratio that is greater than about five (5:1). The low
pressure turbine 46 pressure ratio is pressure measured prior to
inlet of low pressure turbine 46 as related to the pressure at the
outlet of the low pressure turbine 46 prior to an exhaust
nozzle.
[0035] In one disclosed embodiment, the gas turbine engine 20
bypass ratio is greater than about ten (10:1), and the fan diameter
is significantly larger than that of the low pressure compressor
44. The low pressure turbine 46 has a pressure ratio that is
greater than about five (5:1). The geared architecture 48 may be an
epicycle gear train, such as a planetary gear system or other gear
system, with a gear reduction ratio of greater than about 2.5
(2.5:1). It should be understood, however, that the above
parameters are only exemplary of one embodiment of a geared
architecture engine and that the present invention is applicable to
other gas turbine engines including direct drive turbofans.
[0036] A significant amount of thrust is provided by the bypass
flow B due to the high bypass ratio. The fan section 22 of the gas
turbine engine 20 is designed for a particular flight
condition--typically cruise at about 0.8 Mach and about 35,000
feet. The flight condition of 0.8 Mach and 35,000 feet, with the
engine at its best fuel consumption, also known as bucket cruise
Thrust Specific Fuel Consumption ("TSFC"). TSFC is the industry
standard parameter of 1 bm of fuel being burned divided by 1 bf of
thrust the engine produces at that minimum point.
[0037] "Low fan pressure ratio" is the pressure ratio across the
fan blade alone, without a Fan Exit Guide Vane ("FEGV") system. The
low fan pressure ratio as disclosed herein according to one
non-limiting embodiment is less than about 1.45.
[0038] "Low corrected fan tip speed" is the actual fan tip speed in
feet per second divided by an industry standard temperature
correction of [(Tram .degree. R)/518.7).sup.0. 5]. The "Low
corrected fan tip speed" as disclosed herein according to one
non-limiting embodiment is less than about 1150 feet per second
(351 meters per second).
[0039] As shown in FIG. 2, the gas turbine engine 20 includes a
lubrication system 62 that lubricates the bearing system 38. In one
example, the lubrication system 62 lubricates the fan journal
bearings 38a. The lubrication system 62 provides a constant and
uninterrupted supply of lubricant. In one example, the lubricant is
oil. The lubrication system 62 does not depend on gravity or valves
for operation. The lubrication system 62 is also tolerant of debris
and can operate autonomously.
[0040] The lubrication system 62 includes a first reservoir 64 and
a second reservoir 66 that each contain the lubricant. At least one
of the reservoirs 64 and 66 continuously supplies the lubricant to
the bearing system 38 under any operating condition.
[0041] The first reservoir 64 includes a first discharge passage 68
that directs the lubricant to flow from the first reservoir 64 in a
first direction X. In this example, the direction X is generally
downwardly. The second reservoir 66 includes a second discharge
passage 70 that directs the lubricant to flow from the second
reservoir 66 in a second direction Y. In this example, the
direction Y is generally upwardly. In this example, the direction X
is opposite to the direction Y.
[0042] The lubricant in the discharge passage 68 flows to a first
pump 72, and the lubricant in the second discharge passage 70 flows
to a second pump 74. The pumps 72 and 74 are each sized so that the
individual output of each of the pumps 72 and 74 or the combined
output of the pumps 72 and 74 exceed the lubrication or cooling
requirements of the bearing system 38. Although two reservoirs 64
and 66 and two pumps 72 and 84 are illustrated and described, any
number of reservoirs and pumps can be employed in the lubrication
system 62.
[0043] The first pump 72 and the second pump 74 supply the
lubricant to a common manifold 76 through the discharge passages 68
and 70, respectively. The lubricant is discharged from the common
manifold 76 through a common discharge 78 and ultimately to the
bearing system 62. As the flow of the lubricant through the
discharge passages 68 and 70 are in generally opposing directions,
there is a constant and uninterrupted supply of lubricant in case
of a sudden change in altitude of the aircraft or if the aircraft
encounters an air pocket.
[0044] For example, if the aircraft suddenly drops, the lubricant
in the reservoirs 64 and 66 moves towards the upper portion of the
reservoirs 64 and 66. This could interrupt the flow of lubricant
through the discharge passage 68 that directs the lubricant
downwardly. However, as the discharge passage 70 directs the
lubricant upwardly, the lubricant can continue to flow in an
uninterrupted manner through the discharge passage 70.
[0045] In another example, if the aircraft suddenly rises, the
lubricant in the reservoirs 64 and 66 moves towards the lower
portion of the reservoirs 64 and 66. This could interrupt the flow
of lubricant through the discharge passage 70 that directs the
lubricant upwardly. However, as the discharge passage 68 directs
the lubricant downwardly, the lubricant can continue to flow in an
uninterrupted manner through the discharge passage 68.
[0046] In one example, the lubricant flows directly from the common
discharge 78 of the common manifold 76 to the bearing system
38.
[0047] In another example, the lubricant flows from the common
discharge 78 of the common manifold 76 to a valve 80. The valve 80
directs the flow of the lubricant to the bearing system 38 and the
reservoirs 64 and 66 as needed.
[0048] In one example, the valve 80 is a relief valve, which is
passive valve. The valve 80 directs the lubricant to the bearing
system 38 and returns any excess lubricant to replenish the first
reservoir 64 and the second reservoir 66.
[0049] If one of the reservoirs 64 and 66 is empty, the discharge
pressure of the lubricant system 62 drops, closing the valve 80.
The pumps 72 and 74 continue to operate, and the pump 72 and 74
associated with the depleted reservoir 64 and 66 pumps air because
the lubricant is depleted (for example, because of altitude or
gravity vector location, etc.). Initially, the flow of the
lubricant from the full reservoir 64 and 66 creates a seal at the
valve 80 that blocks the flow of air from the empty reservoir 64
and 66 into the valve 80. The lubricant from the reservoir 64 and
66 is pumped to the valve 80, which directs the lubricant to the
reservoir 64 and 66 that is empty. When both the reservoirs 64 and
66 are filled with the lubricant, the lubrication system 62 returns
to its initial state. The valve 80 can then be opened by
pressure.
[0050] In another example, the valve 80 is a control valve, which
is an active valve. Each of the reservoirs 64 and 66 includes a
sensor 82 that detects an amount of the lubricant in each of the
reservoirs 64 and 66. This information is provided to the valve 80.
Based on the information obtained by the sensors 82, the valve 80
can be opened to return the excess lubricant to the reservoir 64
and 66 with the depleted lubricant.
[0051] In another example, the reservoirs 64 and 66 are in direct
communication with each other. In this example, the reservoirs 64
and 66 can supply lubricant to each other when needed to prevent
depletion of the lubricant in either of the reservoirs 64 and
66.
[0052] Although a gas turbine engine 20 with geared architecture 48
is described, the lubrication system 62 can be employed in a gas
turbine engine without geared architecture.
[0053] The foregoing description is only exemplary of the
principles of the invention. Many modifications and variations are
possible in light of the above teachings. It is, therefore, to be
understood that within the scope of the appended claims, the
invention may be practiced otherwise than using the example
embodiments which have been specifically described. For that reason
the following claims should be studied to determine the true scope
and content of this invention.
* * * * *