U.S. patent application number 14/180777 was filed with the patent office on 2015-08-20 for first stage turbine housing for an air cycle machine.
This patent application is currently assigned to Hamilton Sundstrand Corporation. The applicant listed for this patent is Hamilton Sundstrand Corporation. Invention is credited to Craig M. Beers, Seth E. Rosen.
Application Number | 20150233386 14/180777 |
Document ID | / |
Family ID | 53797702 |
Filed Date | 2015-08-20 |
United States Patent
Application |
20150233386 |
Kind Code |
A1 |
Beers; Craig M. ; et
al. |
August 20, 2015 |
FIRST STAGE TURBINE HOUSING FOR AN AIR CYCLE MACHINE
Abstract
A housing of an air cycle machine includes a static seal
portion, a main bore housing portion, a shroud pilot housing
portion, and a thrust plate housing portion. The static seal
portion is arranged about a central axis and defines static seal
radius D.sub.1. The main bore housing portion is arranged about the
central axis and circumscribes the shaft arranged along the central
axis. The main bore housing defines central bore inner radius
D.sub.2. The shroud pilot housing radius is arranged about the
central axis and defines shroud pilot radius D.sub.3. The thrust
plate housing portion is arranged about the central axis and
defines insulator seal plate radius D.sub.4. A ratio
D.sub.1/D.sub.2 is 0.8394 to 0.8416, a ratio D.sub.1/D.sub.3 is
0.4315 to 0.4322, a ratio D.sub.1/D.sub.4 is 0.2517 to 0.2521, a
ratio D.sub.2/D.sub.3 is 0.5130 to 0.5146, a ratio D.sub.2/D.sub.4
is 0.2993-0.3001, and a ratio D.sub.3/D.sub.4 is 0.5828-0.5838.
Inventors: |
Beers; Craig M.;
(Wethersfield, CT) ; Rosen; Seth E.; (Middletown,
CT) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hamilton Sundstrand Corporation |
Windsor Locks |
CT |
US |
|
|
Assignee: |
Hamilton Sundstrand
Corporation
Windsor Locks
CT
|
Family ID: |
53797702 |
Appl. No.: |
14/180777 |
Filed: |
February 14, 2014 |
Current U.S.
Class: |
415/111 |
Current CPC
Class: |
F04D 29/4206 20130101;
F04D 29/624 20130101; F04D 29/056 20130101; F04D 25/024
20130101 |
International
Class: |
F04D 29/40 20060101
F04D029/40 |
Claims
1. A housing of an air cycle machine, the housing comprising: a
static seal portion arranged about a central axis and configured to
circumscribe a static seal defined by a shaft arranged along the
central axis, the static seal portion defining a static seal radius
D.sub.1; a main bore housing portion arranged about the central
axis and positioned longitudinally adjacent to the static seal
portion, the main bore housing configured to circumscribe the
shaft, the main bore housing defining a central bore inner radius
D.sub.2; a shroud pilot housing portion arranged about the central
axis, the shroud pilot housing portion defining a shroud pilot
radius D.sub.3; and an insulator seal plate housing portion
arranged about the central axis and configured to mate with an
adjacent turbine section component, the insulator seal plate
housing portion defining an insulator seal plate radius D.sub.4,
wherein a ratio D.sub.1/D.sub.2 is 0.8394 to 0.8416, a ratio
D.sub.1/D.sub.3 is 0.4315 to 0.4322, a ratio D.sub.1/D.sub.4 is
0.2517 to 0.2521, a ratio D.sub.2/D.sub.3 is 0.5130 to 0.5146, a
ratio D.sub.2/D.sub.4 is 0.2993-0.3001, and a ratio D.sub.3/D.sub.4
is 0.5828-0.5838.
2. The housing of claim 1 wherein the static seal radius is between
2.0724 cm and 2.07365 cm.
3. The housing of claim 1 wherein the main bore housing radius is
between 2.4638 cm and 2.4689 cm.
4. The housing of claim 1 wherein the shroud pilot housing radius
is between 4.79805 cm and 4.80315 cm.
5. The housing of claim 1 wherein the insulator seal plate housing
radius is between 8.22705 cm and 8.23215 cm.
6. The housing of claim 1, wherein the turbine section component is
a turbine section housing.
7. The housing of claim 1, wherein the turbine section component is
a first stage turbine section housing.
8. The housing of claim 1, wherein the shroud housing pilot portion
is configured to mate with an adjacent turbine section
component.
9. An air cycle machine comprises: a shaft; a fan section arranged
around a portion of the shaft, the fan section capable of routing a
first working fluid; a compressor section arranged adjacent to the
fan section and positioned around the shaft, the compressor section
capable of compressing a second working fluid; a turbine section
arranged adjacent to the compressor section and positioned around
the shaft, the turbine section capable of converting potential
energy of the second working fluid to rotational energy; a heat
exchanger capable of exchanging heat between the first working
fluid and the second working fluid; and a housing comprising: a
static seal portion arranged about a central axis and configured to
circumscribe a static seal defined by a shaft arranged along the
central axis, the static seal portion defining a static seal radius
D.sub.1; a main bore housing portion arranged about the central
axis and positioned longitudinally adjacent to the static seal
portion, the main bore housing configured to circumscribe the
shaft, the main bore housing defining a central bore inner radius
D.sub.2; a shroud pilot housing portion arranged about the central
axis, the shroud pilot housing portion defining a shroud pilot
radius D.sub.3; and an insulator seal plate housing portion
arranged about the central axis and configured to mate with an
adjacent turbine section component, the insulator seal plate
housing portion defining an insulator seal plate radius D.sub.4,
wherein a ratio D.sub.1/D.sub.2 is 0.8394 to 0.8416, a ratio
D.sub.1/D.sub.3 is 0.4315 to 0.4322, a ratio D.sub.1/D.sub.4 is
0.2517 to 0.2521, a ratio D.sub.2/D.sub.3 is 0.5130 to 0.5146, a
ratio D.sub.2/D.sub.4 is 0.2993-0.3001, and a ratio D.sub.3/D.sub.4
is 0.5828-0.5838.
10. The air cycle machine of claim 9, wherein the second working
fluid passes through the heat exchanger between the compressor
section and the turbine section.
11. The air cycle machine of claim 9, wherein the fan section, the
compressor section, and the turbine section are connected by the
shaft to form a single spool.
12. The housing of claim 9 wherein the static seal radius is
between 0.8159 in. and 0.8164 in.
13. The housing of claim 9 wherein the main bore housing radius is
between 0.9700 in. and 0.9720 in.
14. The housing of claim 9 wherein the shroud pilot housing radius
is between 1.8890 in. and 1.8910 in.
15. The housing of claim 9 wherein the insulator seal plate housing
radius is between 3.2390 in. and 3.2410 in.
Description
BACKGROUND
[0001] The present invention relates to Air Cycle Machines (ACMs).
ACMs may be used to compress air in a compressor section. The
compressed air is discharged to a downstream heat exchanger and
further routed to a turbine. The turbine extracts energy from the
expanded air to drive the compressor. The air output from the
turbine may be utilized as an air supply for a vehicle, such as the
cabin of an aircraft. ACMs may be used to achieve a desired
pressure, temperature, and humidity in the air that is transferred
to the environmental control system of the aircraft.
[0002] ACMs often have a three-wheel or four-wheel configuration.
In a three-wheel ACM, a turbine drives both a compressor and a fan
which rotate on a common shaft. In a four-wheel ACM, two turbine
sections drive a compressor and a fan on a common shaft.
[0003] Airflow from one working fluid must be directed through a
ram circuit consisting of a heat exchanger and the fan section of
the ACM. Airflow from a second working fluid must be directed into
the compressor section, away from the compressor section towards
the heat exchanger, from the heat exchanger to the turbine or
turbines, and from the final turbine stage out of the ACM. In at
least some of these transfers, it is desirable to direct air
radially with respect to the central axis of the ACM. To accomplish
this, rotating nozzles may be used to generate radial in-flow
and/or out-flow.
[0004] ACMs often have more than one housing section. The housings
used in an ACM are used to contain airflow routed through the ACM,
as well as rotating parts. Often, housing components are configured
adjacent to seals and/or other housing components to achieve
airflow containment.
SUMMARY
[0005] A housing of an air cycle machine includes a static seal
portion, a main bore housing portion, a shroud pilot housing
portion, and a thrust plate housing portion. The static seal
portion is arranged about a central axis and defines static seal
radius D.sub.1. The main bore housing portion is arranged about the
central axis and circumscribes the shaft arranged along the central
axis. The main bore housing defines central bore inner radius
D.sub.2. The shroud pilot housing radius is arranged about the
central axis and defines shroud pilot radius D.sub.3. The thrust
plate housing portion is arranged about the central axis and
defines insulator seal plate radius D.sub.4. A ratio
D.sub.1/D.sub.2 is 0.8394 to 0.8416, a ratio D.sub.1/D.sub.3 is
0.4315 to 0.4322, a ratio D.sub.1/D.sub.4 is 0.2517 to 0.2521, a
ratio D.sub.2/D.sub.3 is 0.5130 to 0.5146, a ratio D.sub.2/D.sub.4
is 0.2993-0.3001, and a ratio D.sub.3/D.sub.4 is 0.5828-0.5838.
[0006] An air cycle machine includes a fan section arranged around
a shaft. The fan section is capable of routing a first working
fluid. A compressor section is arranged next to the fan section and
positioned around the shaft and is capable of compressing a second
working fluid. A turbine section is arranged next to the compressor
section and positioned around the shaft. The turbine section is
capable of converting potential energy of the second working fluid
into rotational energy. A heat exchanger is capable of exchanging
heat between the first working fluid and the second working fluid.
A housing of an air cycle machine includes a static seal portion, a
main bore housing portion, a shroud pilot housing portion, and a
thrust plate housing portion. The static seal portion is arranged
about a central axis and defines static seal radius D.sub.1. The
main bore housing portion is arranged about the central axis and
circumscribes the shaft arranged along the central axis. The main
bore housing defines central bore inner radius D.sub.2. The shroud
pilot housing radius is arranged about the central axis and defines
shroud pilot radius D.sub.3. The thrust plate housing portion is
arranged about the central axis and defines insulator seal plate
radius D.sub.4. A ratio D.sub.1/D.sub.2 is 0.8394 to 0.8416, a
ratio D.sub.1/D.sub.3 is 0.4315 to 0.4322, a ratio D.sub.1/D.sub.4
is 0.2517 to 0.2521, a ratio D.sub.2/D.sub.3 is 0.5130 to 0.5146, a
ratio D.sub.2/D.sub.4 is 0.2993-0.3001, and a ratio D.sub.3/D.sub.4
is 0.5828-0.5838.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a cross-sectional view of an air cycle
machine.
[0008] FIG. 2 is a perspective view of a housing of the air cycle
machine.
DETAILED DESCRIPTION
[0009] The dimensions of an air cycle machine housing are selected
in order to achieve several goals. Reduced drag of rotating shaft
on static shaft seal minimizes friction losses and transfers more
turbine power to the compressor and fan. Seal clearance is
desirably minimized, in order to minimize compressor inlet flow
lost through the seal. Shaft excursions, such as seals, result in
intimate contact between shaft seal teeth and associated seal
lands. The seal clearance losses are balanced against the
frictional losses of seal drag during shaft excursions. Clearance
is maintained between the rotating shaft teeth and the seal land to
reduce or eliminate sub-synchronous vibrations in foil bearings of
the air cycle machine. Further, the leakage from excursions such as
seals is prevented from dumping into part of the bearing cooling
flow path. Excessive leakage into this flowpath could result in a
blockage of cooling flow. Seal sizing prevents the excessive
leakage that could cause reduced bearing cooling flow and
over-temperature of the bearing surfaces.
[0010] Optimizing performance of a compressor and a turbine can be
quite different. For a compressor, the inlet air is at a lower
pressure than the outlet air, but the opposite is true for a
turbine. Also, the compressor inlet air contains a high
temperature, and the compressor discharge temperature is even
greater. For the turbine, the inlet air is at a cool temperature
and the outlet is at an even colder temperature. When the
compressor and turbine parts are optimized, different methodologies
are required for the turbine and compressor. If the turbine were
designed using an the incorrect optimization technique, either the
clearance would be too loose and cause poor turbine performance or
the seal clearance would be too tight and cause a side loading of
the foil bearings. In the specific instance of the seal clearance
being too tight, the foil bearings would be excessively side loaded
and result in poor reliability or reduced load capability. One
feature of this ACM is the use of the bearing clearances and seal
sizes to prevent excessively side-loading the bearings without
having any negative impact on turbine performance or additional
bearing cooling.
[0011] FIG. 1 is a cross-sectional view of ACM 2, which is a
four-wheel ACM. As shown in FIG. 1, ACM 2 includes fan section 4,
compressor section 6, first stage turbine section 8, and second
stage turbine section 10, which are all connected to shaft 12.
Shaft 12 rotates about central axis 14.
[0012] Fan section 4, compressor section 6, first stage turbine
section 8, and second stage turbine section 10 are also connected
to one another via shaft 12. Shaft 12 runs along central axis 14,
and is connected to at least compressor nozzle 26, first stage
turbine nozzle 32, and second stage turbine nozzle 38. Fan blades
20 may also be connected to shaft 12.
[0013] When working fluid passes through ACM 2, it is first
compressed in compressor section 6, and then expanded in first
stage turbine section 8 and second stage turbine section 10. Often,
a first working fluid is heated or cooled in a heat exchanger (not
shown) through which working fluid is routed as it passes between
compressor section 6 and first stage turbine section 8. First stage
turbine section 8 and second stage turbine section 10 extract
energy from the working fluid, turning shaft 12 about central axis
14. Meanwhile, a second working fluid is routed through the same
heat exchanger by fan section 4. For example, the first working
fluid may be routed from a bleed valve of a gas turbine engine
through compressor section 6, to a heat exchanger, to first stage
turbine section 8, then to second stage turbine section 10, and
then to the environmental control system of an aircraft. The second
working fluid may be ram air that is pulled by fan section 4
through the same heat exchanger to cool the first working fluid to
a desired temperature before routing of the first working fluid to
the turbine sections 8 and 10. By compressing, heating, and
expanding the working fluid, the output provided at the second
stage turbine 10 may be adjusted to a desired temperature,
pressure, and/or relative humidity.
[0014] Fan section 4 includes fan inlet 16 and fan outlet 18. Fan
inlet 16 is an opening in ACM 2 that receives working fluid from
another source, such as a ram air scoop. Fan outlet 18 allows
working fluid to escape fan section 4. Fan blades 20 may be used to
draw working fluid into fan section 4.
[0015] Compressor section 6 includes compressor inlet 22,
compressor outlet 24, compressor nozzle 26, and compressor blades
27. Compressor inlet 22 is a duct defining an aperture through
which working fluid to be compressed is received from another
source. Compressor outlet 24 allows working fluid to be routed to
other systems after it has been compressed. Compressor nozzle 26 is
a nozzle section that rotates through working fluid in compressor
section 6. Compressor nozzle 26 directs working fluid from
compressor inlet 22 to compressor outlet 24 via compressor blades
27. Compressor nozzle 26 is a radial out-flow rotor.
[0016] First stage turbine section 8 includes first stage turbine
inlet 28, first stage turbine outlet 30, first stage turbine nozzle
32, and first stage turbine blades 33. First stage turbine inlet 28
is a duct defining an aperture through which working fluid passes
prior to expansion in first stage turbine section 8. First stage
turbine outlet 30 is a duct defining an aperture through which
working fluid (which has expanded) departs first stage turbine
section 8. First stage turbine nozzle 32 is a nozzle section that
rotates through working fluid in first stage turbine section 8.
First stage turbine nozzle 32 cooperates with first stage turbine
blades 33 to extract energy from working fluid passing
therethrough, driving the rotation of first stage turbine section 8
and attached components, including shaft 12, fan section 4, and
compressor section 6. First stage turbine nozzle 32 is a radial
in-flow rotor.
[0017] Second stage turbine section 10 includes second stage
turbine inlet 34, second stage turbine outlet 36, second stage
turbine nozzle 38, and second stage turbine blades 39. Second stage
turbine inlet 34 is a duct defining an aperture through which
working fluid passes prior to expansion in second stage turbine
section 10. Second stage turbine outlet 36 is a duct defining an
aperture through which working fluid (which has expanded) departs
second stage turbine section 10. Second stage turbine nozzle 38 is
a nozzle section that cooperates with second stage turbine blades
39 to extract energy from working fluid passing therethrough,
driving the rotation of second stage turbine section 10 and
attached components, including shaft 12, fan section 4, and
compressor section 6. In particular, second stage turbine nozzle 38
is a radial out-flow rotor. Working fluid passes from second stage
turbine inlet 34 to cavity 35, where it is incident upon second
stage turbine nozzle 38. Working fluid then passes between nozzle
blades (not shown). Turbine nozzle 38 is stationary, and the nozzle
vanes guide the flow for optimum entry into the turbine rotor. The
flow of causes turbine blades 39 to rotate and turn shaft 12.
[0018] Shaft 12 is a rod, such as a titanium tie-rod, used to
connect other components of ACM 2. Shaft 12 includes a seal portion
arranged partway along its length. Central axis 14 is an axis with
respect to which other components may be arranged.
[0019] Fan section 4 is connected to compressor section 6. In
particular, fan outlet 18 is coupled to compressor inlet 22.
Working fluid is drawn through fan inlet 16 and discharged through
fan outlet 18 by fan blades 20. Working fluid from fan outlet 18 is
routed to compressor inlet 22 for compression in compressor section
6. Similarly, compressor section 6 is coupled with first stage
turbine section 8. Working fluid from compressor outlet 24 is
routed to first stage turbine inlet 28.
[0020] Fan section 4 and compressor section 6 share housing 40.
Housing 40 encloses the moving parts and air paths through fan
section 4 and compressor section 6. The size and geometry of
housing 40 define the flow of air through ACM 2. For example,
housing 40 is arranged about shaft 12 so as to prevent excessive
airflow around shaft 12. In particular, a static seal portion is
included in shaft 12, directly adjacent to static seal portion 44.
The outer radius of the seal portion is set such that a seal is
formed with static seal portion 44 of housing 40. Thus, the outer
radius of shaft 12 at the static seal portion is equal to or
slightly less than static seal radius D1.
[0021] Housing 40 has specific dimensions to coordinate with
adjacent housing sections, such as the housing surrounding turbine
section 8. Housing 40 includes main bore housing portion 42, static
seal portion 44, shroud pilot housing 46, and thrust plate 48.
[0022] Static seal portion 44 is the portion of housing 40 that
circumscribes shaft 12 at the longitudinal are at which shaft 12
includes a seal. In this way, static seal portion 44 prevents flow
of fluid between housing 40 and shaft 12. The radius of housing 40
from central axis 14 to static seal portion 44 is illustrated as
static seal radius D1. Static seal radius D1 is between 2.0724 cm
and 2.07365 cm (0.8159 in. and 0.8164 in.).
[0023] Main bore housing portion 42 is the portion of housing 40
that circumscribes shaft 12 so as to prevent excessive airflow
around shaft 12. The radius of housing 40 from central axis 14 to
main bore housing portion 42 is illustrated as central bore inner
radius D2. Central bore inner radius D2 is between 2.4638 cm and
2.4689 cm (0.9700 in. and 0.9720 in.).
[0024] Shroud pilot housing 46 defines a portion of housing 40 at
the point where the radial distance between central axis 14 and
housing 40 is at a local minimum. Shroud pilot housing portion 46
is configured to mate with a complimentary feature, turbine housing
50. By coupling with turbine housing 50, shroud pilot housing 46
prevents working fluid passing through the compressor inlet 22 from
intermixing with compressed fluid at the compressor outlet 24. The
radius of housing 40 from central axis 14 to shroud pilot housing
46 is illustrated as shroud pilot housing radius D3. Shroud pilot
housing radius D3 is between 4.79805 cm and 4.80315 cm (1.8890 in.
and 1.8910 in.).
[0025] Thrust plate 48 is a portion of housing 40 that extends
between first stage turbine section 8 and second stage turbine
section 10. Thrust plate 48 separates second stage turbine inlet 34
and cavity 35. The radius from central axis 14 to thrust plate 48
is illustrated as thrust plate radius D4. Thrust plate housing
radius D4 is between 8.22705 cm and 8.23215 cm (3.2390 in. and
3.2410 in.).
[0026] The ratios between static seal radius D1, central bore inner
radius D2, shroud pilot housing radius D3, and thrust plate housing
radius D4 can also be set to reach optimized bearing cooling and
seal leakage throughout ACM 2. Optimized clearance of seals in ACM
2 also permits proper operation of the shaft/rotor system. The
following ratios are preferable as between D1, D2, D3, and D4:
D1/D2 is 0.8394 to 0.8416, a ratio D1/D3 is 0.4315 to 0.4322, a
ratio D1/D4 is 0.2517 to 0.2521, a ratio D2/D3 is 0.5130 to 0.5146,
a ratio D2/D4 is 0.2993-0.3001, and a ratio D3/D4 is
0.5828-0.5838
[0027] FIG. 2 is a perspective view of housing 40, illustrating
static seal radius D1, central bore inner radius D2, shroud pilot
housing radius D3, and thrust plate radius D4. Components of ACM 2
of FIG. 1, including the adjacent housing of turbine section 8 and
shaft 12, have been removed to more clearly illustrate the specific
dimensions of housing 40. As previously described with respect to
FIG. 1, a static seal portion D1, main bore housing radius D2,
shroud pilot housing radius D3, and thrust plate housing radius D4
have specific ranges of dimensions that are optimal.
Discussion of Possible Embodiments
[0028] The following are non-exclusive descriptions of possible
embodiments of the present invention.
[0029] A housing of an air cycle machine may include a static seal
portion arranged about a central axis and configured to
circumscribe a static seal defined by a shaft arranged along the
central axis. The static seal portion defines a static seal radius
D.sub.1. A main bore housing portion is arranged about the central
axis and positioned longitudinally adjacent to the static seal
portion. The main bore housing is configured to circumscribe the
shaft. The main bore housing defines a central bore inner radius
D.sub.2. A shroud pilot housing portion is arranged about the
central axis. The shroud pilot housing portion defines a shroud
pilot radius D.sub.3. A thrust plate housing portion is arranged
about the central axis and is configured to mate with an adjacent
turbine section component. The thrust plate housing portion
defining an insulator seal plate radius D.sub.4. The ratios as
between D1, D2, D3, and D4 include D.sub.1/D.sub.2 between 0.8394
to 0.8416, D.sub.1/D.sub.3 between 0.4315 to 0.4322,
D.sub.1/D.sub.4 between 0.2517 to 0.2521, D.sub.2/D.sub.3 between
0.5130 to 0.5146, D.sub.2/D.sub.4 between 0.2993-0.3001, and
D.sub.3/D.sub.4 between 0.5828-0.5838.
[0030] The housing of the preceding paragraph can optionally
include, additionally and/or alternatively, any one or more of the
following features, configurations, and/or additional
components.
[0031] The static seal radius may be between 2.0724 cm and 2.07365
cm. The main bore housing radius may be between 2.4638 cm and
2.4689 cm. The shroud pilot housing radius may be between 4.79805
cm and 4.80315 cm. The thrust plate housing radius may be between
8.22705 cm and 8.23215 cm. The turbine section component may be a
turbine section housing. The turbine section component may be a
first stage turbine section housing. The shroud housing pilot
portion may be configured to mate with the adjacent turbine section
component.
[0032] An air cycle machine may include a shaft. The air cycle
machine may further include a fan section arranged around a portion
of the shaft. The fan section is capable of routing a first working
fluid. The air cycle machine includes a compressor section arranged
adjacent to the fan section and positioned around the shaft. The
compressor section is capable of compressing a second working
fluid. The turbine section is arranged adjacent to the compressor
section and positioned around the shaft. The turbine section is
capable of converting potential energy of the second working fluid
to rotational energy. A heat exchanger is capable of exchanging
heat between the first working fluid and the second working fluid.
A housing forms a part of both the fan section and the compressor
section. The housing includes a static seal portion arranged about
a central axis and configured to circumscribe a static seal defined
by a shaft arranged along the central axis. The static seal portion
defines a static seal radius D.sub.1. A main bore housing portion
is arranged about the central axis and positioned longitudinally
adjacent to the static seal portion. The main bore housing is
configured to circumscribe the shaft. The main bore housing defines
a central bore inner radius D.sub.2. A shroud pilot housing portion
is arranged about the central axis. The shroud pilot housing
portion defines a shroud pilot radius D.sub.3. A thrust plate
housing portion is arranged about the central axis and is
configured to mate with an adjacent turbine section component. The
thrust plate housing portion defining an insulator seal plate
radius D.sub.4. The ratios as between D1, D2, D3, and D4 include
D.sub.1/D.sub.2 between 0.8394 to 0.8416, D.sub.1/D.sub.3 between
0.4315 to 0.4322, D.sub.1/D.sub.4 between 0.2517 to 0.2521,
D.sub.2/D.sub.3 between 0.5130 to 0.5146, D.sub.2/D.sub.4 between
0.2993-0.3001, and D.sub.3/D.sub.4 between 0.5828-0.5838.
[0033] The housing of the preceding paragraph can optionally
include, additionally and/or alternatively, any one or more of the
following features, configurations, and/or additional
components.
[0034] The second working fluid may pass through the heat exchanger
located between the compressor section and the turbine section. The
fan section, the compressor section, and the turbine section may be
connected by the shaft to form a single spool. The static seal
radius may be between 0.8159 in. and 0.8164 in. The main bore
housing radius may be between 0.9700 in. and 0.9720 in. The shroud
pilot housing radius may be between 1.8890 in. and 1.8910 in. The
thrust plate housing radius may be between 3.2390 in. and 3.2410
in.
[0035] While the invention has been described with reference to an
exemplary embodiment(s), 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 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(s) disclosed, but that the invention will
include all embodiments falling within the scope of the appended
claims.
* * * * *