U.S. patent application number 13/869563 was filed with the patent office on 2014-10-30 for turbine nozzle piece parts with hvoc coatings.
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, Darryl A. Colson, Seth E. Rosen.
Application Number | 20140321979 13/869563 |
Document ID | / |
Family ID | 51766789 |
Filed Date | 2014-10-30 |
United States Patent
Application |
20140321979 |
Kind Code |
A1 |
Beers; Craig M. ; et
al. |
October 30, 2014 |
TURBINE NOZZLE PIECE PARTS WITH HVOC COATINGS
Abstract
A nozzle for an air cycle machine. The nozzle has a disk section
having a central axis. The nozzle also includes a plurality of
blades which extend a blade height H from a bladed face of the disk
section. The plurality of blades are arranged radially about the
disk section. The nozzle has a throat width W defined between each
radially adjacent pair of the plurality of turbine blades. The
nozzle includes a coating substantially encapsulating the disk
section and the plurality of blades, wherein the coating contains
more than 91 percent tungsten carbide by volume.
Inventors: |
Beers; Craig M.;
(Wethersfield, CT) ; Colson; Darryl A.; (West
Suffield, 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: |
51766789 |
Appl. No.: |
13/869563 |
Filed: |
April 24, 2013 |
Current U.S.
Class: |
415/115 |
Current CPC
Class: |
F01D 5/288 20130101;
F02C 1/02 20130101; F01D 5/141 20130101; F05D 2230/80 20130101;
F01D 9/045 20130101 |
Class at
Publication: |
415/115 |
International
Class: |
F01D 9/02 20060101
F01D009/02 |
Claims
1. A nozzle for an air cycle machine, comprising: a disk section
having a central axis; a plurality of blades which extend a blade
height H from a bladed face of the disk section, the plurality of
blades arranged radially about the disk section; a throat width W
defined between each radially adjacent pair of the plurality of
turbine blades; and a coating substantially encapsulating the disk
section and the plurality of blades, wherein the coating contains
more than 91 percent tungsten carbide by volume.
2. The nozzle of claim 1, wherein the coating contains less than 8
percent cobalt by volume.
3. The nozzle of claim 1, wherein the plurality of blades consists
of 34 blades.
4. The nozzle of claim 1, wherein the blade height H is 0.940
cm.
5. The nozzle of claim 1, wherein the throat width is 0.222 cm.
6. The nozzle of claim 1, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 7.103
cm square.
7. The nozzle of claim 1, wherein the plurality of blades consists
of 19 blades.
8. The nozzle of claim 1, wherein the blade height H is 0.686
cm.
9. The nozzle of claim 1, wherein the throat width is 0.340 cm.
10. The nozzle of claim 1, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 4.432
cm square.
11. The nozzle of claim 1, wherein the blade height H is 0.318
cm.
12. The nozzle of claim 1, wherein the blade height H is 0.393
cm.
13. The nozzle of claim 1, wherein the throat width is 0.241
cm.
14. The nozzle of claim 1, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.451
cm square.
15. The nozzle of claim 1, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.806
cm square.
16. The nozzle of claim 1, wherein the plurality of blades consists
of 23 blades.
17. The nozzle of claim 1, wherein the blade height H is 0.305
cm.
18. The nozzle of claim 1, wherein the throat width is 0.234
cm.
19. The nozzle of claim 1, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.639
cm square.
20. The nozzle of claim 1, wherein the coating has a thickness
between 50.8 .mu.m and 101.6 .mu.m.
21. The nozzle of claim 1, wherein the coating comprises a metal
alloy having a surface coating adhesion strength greater than
10,000 psi.
22. The nozzle of claim 20, wherein the coating comprises a metal
alloy having a surface coating adhesion strength greater than
10,000 psi.
23. A nozzle for an air cycle machine, comprising: a disk section
having a central axis; a plurality of blades which extend a blade
height H from a bladed face of the disk section, the plurality of
blades arranged radially about the disk section; a throat width W
defined between each radially adjacent pair of the plurality of
turbine blades; and a coating substantially encapsulating the disk
section and the plurality of blades, wherein the coating has a
thickness between 50.8 .mu.m and 101.6 .mu.m.
24. The nozzle of claim 23, wherein the coating contains less than
8 percent cobalt by volume.
25. The nozzle of claim 23, wherein the plurality of blades
consists of 34 blades.
26. The nozzle of claim 23, wherein the blade height His 0.940
cm.
27. The nozzle of claim 23, wherein the throat width is 0.222
cm.
28. The nozzle of claim 23, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 7.103
cm square.
29. The nozzle of claim 23, wherein the plurality of blades
consists of 19 blades.
30. The nozzle of claim 23, wherein the blade height H is 0.686
cm.
31. The nozzle of claim 23, wherein the throat width is 0.340
cm.
32. The nozzle of claim 23, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 4.432
cm square.
33. The nozzle of claim 23, wherein the blade height H is 0.318
cm.
34. The nozzle of claim 23, wherein the blade height H is 0.393
cm.
35. The nozzle of claim 23, wherein the throat width is 0.241
cm.
36. The nozzle of claim 23, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.451
cm square.
37. The nozzle of claim 23, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.806
cm square.
38. The nozzle of claim 23, wherein the plurality of blades
consists of 23 blades.
39. The nozzle of claim 23, wherein the blade height H is 0.305
cm.
40. The nozzle of claim 23, wherein the throat width is 0.234
cm.
41. The nozzle of claim 23, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.639
cm square.
42. The nozzle of claim 23, wherein the coating comprises a metal
alloy having a surface adhesion strength greater than 10,000
psi.
43. A nozzle for an air cycle machine, comprising: a disk section
having a central axis; a plurality of blades which extend a blade
height H from a bladed face of the disk section, the plurality of
blades arranged radially about the disk section; a throat width W
defined between each radially adjacent pair of the plurality of
turbine blades; and a coating substantially encapsulating the disk
section and the plurality of blades, wherein the coating comprises
a metal alloy having a surface coating adhesion strength greater
than 10,000 psi.
44. The nozzle of claim 43, wherein the coating contains less than
8 percent cobalt by volume.
45. The nozzle of claim 43, wherein the plurality of blades
consists of 34 blades.
46. The nozzle of claim 43, wherein the blade height H is 0.940
cm.
47. The nozzle of claim 43, wherein the throat width is 0.222
cm.
48. The nozzle of claim 43, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 7.103
cm square.
49. The nozzle of claim 43, wherein the plurality of blades
consists of 19 blades.
50. The nozzle of claim 43, wherein the blade height H is 0.686
cm.
51. The nozzle of claim 43, wherein the throat width is 0.340
cm.
52. The nozzle of claim 43, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 4.432
cm square.
53. The nozzle of claim 43, wherein the blade height H is 0.318
cm.
54. The nozzle of claim 43, wherein the blade height H is 0.393
cm.
55. The nozzle of claim 43, wherein the throat width H is 0.241
cm.
56. The nozzle of claim 43, and further including a flow area A
defined by the surface area of the bladed face of the disk less the
area covered by the plurality of blades, and wherein the flow area
A is equal to 1.451 cm square.
57. The nozzle of claim 43, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.806
cm square.
58. The nozzle of claim 43, wherein the plurality of blades
consists of 23 blades.
59. The nozzle of claim 43, wherein the blade height H is 0.305
cm.
60. The nozzle of claim 43, wherein the throat width is 0.234
cm.
61. The nozzle of claim 43, and further including a flow area A
defined by the surface area along the bladed face of the disk and
between the blades, and wherein the flow area A is equal to 1.639
cm square.
Description
BACKGROUND
[0001] The present invention relates to Air Cycle Machines (ACM),
such as the type used in Environmental Control Systems in aircraft.
In particular, the present invention relates to novel dimensions
and coatings of turbine nozzles used in ACMs.
[0002] 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.
[0003] 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.
[0004] Airflow must be directed into the fan section to 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.
[0005] Often, it is desirable for components such as nozzles to
include coatings that protect the components from damage. For
example, tungsten carbide coatings have been applied using
detonation gun coating.
[0006] Thermal spraying techniques are known in the art and are
often used to apply thick coatings to change surface properties of
the component. Examples of known thermal spraying techniques
include detonation gun coating, in which high pressure shock waves
pass through a gas stream and cause the emission of bursts of the
material to be deposited. Another known method of thermal spraying
is high velocity oxy fuel (HVOF), in which the fuel combusts
continuously, allowing for a continuous stream of material to be
deposited.
SUMMARY
[0007] In one embodiment, a nozzle for an air cycle machine is
disclosed which includes a disk section having a central axis. The
nozzle also includes blades which extend from a bladed face of the
disk section by a blade height H. The blades are arranged radially
about the disk section. A throat width W is defined between each
radially adjacent pair of the plurality of turbine blades. A
coating substantially encapsulates the disk section and the
plurality of blades, wherein the coating contains more than 91
percent tungsten carbide by volume.
[0008] In another embodiment, a nozzle for an air cycle machine is
disclosed which also includes a disk section having a central axis.
The nozzle also includes blades which extend from a bladed face of
the disk section by a blade height H. The blades are arranged
radially about the disk section. A throat width W is defined
between each radially adjacent pair of the plurality of turbine
blades. The coating substantially encapsulating the disk section
and the plurality of blades has a thickness between 50.8 .mu.m and
101.6 .mu.m.
[0009] In a third embodiment, a nozzle for an air cycle machine is
disclosed which also includes a disk section having a central axis.
The nozzle also includes blades which extend from a bladed face of
the disk section by a blade height H. The blades are arranged
radially about the disk section. A throat width W is defined
between each radially adjacent pair of the plurality of turbine
blades. The coating substantially encapsulating the disk section
and the plurality of blades comprises a metal alloy having a bond
strength greater than 10,000 psi.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a cross-sectional view of a four-wheel Air Cycle
Machine.
[0011] FIG. 2 is a plan view of a turbine nozzle in the four-wheel
Air Cycle Machine of FIG. 1.
[0012] FIG. 3 is a side view of the turbine nozzle of FIG. 2.
[0013] FIG. 4 is a plan view of a portion of the turbine nozzle of
FIG. 2, showing the dimensions of the nozzle.
[0014] FIG. 5 is a plan view of a turbine nozzle in the four-wheel
Air Cycle Machine of FIG. 1.
[0015] FIG. 6 is a side view of the turbine nozzle of FIG. 5.
[0016] FIG. 7 is a plan view of a portion of the turbine nozzle of
FIG. 5, showing the dimensions of the nozzle.
[0017] FIG. 8 is a cross-sectional view of a three-wheel Air Cycle
Machine.
[0018] FIG. 9 is a plan view of a turbine nozzle in the three-wheel
Air Cycle Machine of FIG. 8.
[0019] FIG. 10 is a side view of the turbine nozzle of FIG. 9.
[0020] FIG. 11 is a plan view of a portion of the turbine nozzle of
FIG. 9, showing the dimensions of the nozzle.
[0021] FIG. 12 is a plan view of a turbine nozzle in the
three-wheel Air Cycle Machine of FIG. 8.
[0022] FIG. 13 is a side view of the turbine nozzle of FIG. 12.
[0023] FIG. 14 is a plan view of a portion of the turbine nozzle of
FIG. 12, showing the dimensions of the nozzle.
DETAILED DESCRIPTION
[0024] FIG. 1 is a cross-sectional view of Air Cycle Machine (ACM)
2. ACM 2 is a four-wheel ACM, containing fan section 4, compressor
section 6, first turbine section 8, and second turbine section 10,
which are all connected to shaft 12. Shaft 12 rotates about central
axis 14.
[0025] 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.
[0026] 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.
[0027] First turbine section 8 includes first stage turbine inlet
28, first stage turbine outlet 30, first stage turbine nozzle 32,
and first turbine blades 33. First stage turbine inlet 28 is a duct
defining an aperture through which working fluid passes prior to
expansion in first turbine section 8. First stage turbine outlet 30
is a duct defining an aperture through which working fluid (which
has expanded) departs first turbine section 8. First stage turbine
nozzle 32 is a nozzle section that rotates through working fluid in
first turbine section 8. First stage turbine nozzle 32 cooperates
with first stage turbine blades 37 to extract energy from working
fluid passing therethrough, driving the rotation of first 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.
[0028] Second 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 turbine section 10. Second
stage turbine outlet 36 is a duct defining an aperture through
which working fluid (which has expanded) departs second 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 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 50 and 52 (FIGS. 5-7). 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 turb shaft 12.
[0029] Shaft 12 is a rod, such as a titanium tie-rod, used to
connect other components of ACM 2. Central axis 14 is an axis with
respect to which other components may be arranged.
[0030] 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 turbine
section 8. Working fluid from compressor outlet 24 is routed to
first stage turbine inlet 28.
[0031] Similarly, first turbine section 8 is coupled to second
turbine section 10. Working fluid from first stage turbine outlet
30 is routed to second stage turbine inlet 34. In this way, working
fluid passes through ACM 2: first through fan inlet 16, then fan
outlet 18, compressor inlet 22, compressor outlet 24, first stage
turbine inlet 28, first stage turbine outlet 30, second stage
turbine inlet 34, and second stage turbine outlet 38. Additional
stages may exist between those shown in FIG. 1. For example, often
a heat exchanger (not shown) is located between compressor section
6 and first turbine section 8.
[0032] Each of fan section 4, compressor section 6, first turbine
section 8, and second 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.
[0033] When working fluid passes through ACM 2, it is first
compressed in compressor section 6, then expanded in first turbine
section 8 and second turbine section 10. Often, the working fluid
is also heated or cooled in a heat exchanger (not shown) through
which working fluid is routed as it passes between compressor
section 6 and first turbine section 8. First turbine section 8 and
second turbine section 10 extract energy from the working fluid,
turning shaft 12 about central axis 14.
[0034] Working fluid passing through ACM 2 may be conditioned for
use in the central cabin of a vehicle powered by a gas turbine
engine. By compressing, heating, and expanding the working fluid,
it may be adjusted to a desired temperature, pressure, and/or
relative humidity. However, due to the rapid rotation of compressor
nozzle 26, first stage turbine nozzle 32, and second stage turbine
nozzle 38 with respect to the working fluid flowpath, these parts
need frequent replacement.
[0035] FIG. 2 is a plan view of first stage turbine nozzle 32
arranged about central axis 14. First stage turbine nozzle 32
includes nineteen full blades 40 arranged along a surface of disk
42. Full blades 40 and disk 42 are made of a durable material such
as steel, aluminum, or titanium. First stage turbine nozzle 32 is
coated with tungsten carbide. The tungsten carbide coating on first
stage turbine nozzle 32 is applied using HVOF, allowing for
increased hardness and a higher percentage of tungsten carbide as
opposed to other materials, such as cobalt. HVOF spraying also
results in reduced variability in coating thickness as compared to
traditional coating methods, such as deposition gun spraying.
[0036] Disk 42 is radially symmetrical about central axis 14. Full
blades 40 are spaced equidistantly from one another about the
circumferential length of disk 42. Each of full blades 40 are also
equidistant radially from central axis 14.
[0037] First stage turbine nozzle 32 is a high value component that
is relatively frequently replaced. Damage to first stage turbine
nozzle 32 may occur due to contact with abrasive particles. Thus, a
high strength, durable coating may increase the service life of
first stage turbine nozzle 32.
[0038] FIG. 3 is a side view of first stage turbine nozzle 32.
First stage turbine nozzle 32 contains full blades 40 and disk 42,
as described with respect to FIG. 2.
[0039] FIG. 3 illustrates the thickness of first stage turbine
nozzle 32. In particular, first stage turbine nozzle 32 includes
blade height H32. Blade height H32 is the amount of head space
between disk 42 and an adjacent component such as a shroud (not
shown). Blade height H32 as shown in FIG. 3 is 0.686 cm (0.270
in.). In some embodiments, blade height H32 may vary by as much as
0.01 cm (0.005 in.). However, blade height H32 of 0.686 cm is ideal
for the passage of the desired quantity of working fluid through
first turbine section 8 (FIG. 1).
[0040] FIG. 4 is an enlarged view of a portion of first stage
turbine nozzle 32. The portion shown in FIG. 4 shows full blades 40
arranged on disk 42.
[0041] FIG. 4 illustrates various specific dimensions of first
stage turbine nozzle 32. Nozzle passage width W32 is the distance
between each full blade 40 and the radially adjacent full blade 40.
In effect, nozzle passage width W32 is the width of a throat
through which working air may be routed. Nozzle passage width W32
is 0.340 cm. (0.134 in.), but may deviate by as much as 0.013 cm.
(0.005 in.). Flow area A32 is the region through which working
fluid may flow. Flow area A32 converges between the vanes until it
reaches the throat of first stage turbine nozzle 32, and has a
surface area of nozzle height H32.times.nozzle passage width W32.
Due to machining tolerances, flow area A32 area may vary by up to
5%. Flow area A32 is approximately 4.432 square centimeters (0.687
square in.).
[0042] Nozzle passage width W32 is optimized to ensure proper flow
and energy extraction from first stage turbine nozzle 32.
Increasing or decreasing nozzle passage width W32 would result in
too much or too little flow through first stage turbine nozzle 32
Likewise, flow area A32 is optimized to ensure an appropriate
quantity of working fluid is transmitted by first stage turbine
nozzle 32. A larger flow area A32 would result in too much working
fluid passing through first stage turbine nozzle 32, while a
smaller flow area A32 would result in too little.
[0043] FIG. 5 is a plan view of second stage turbine nozzle 38
arranged about central axis 14. Second stage turbine nozzle 38
includes seventeen full blades 50 and seventeen splitter blades 52
arranged along a surface of disk 54. Full blades 50, splitter
blades 52, and disk 54 are made of a durable material such as
steel, aluminum, or titanium. Second stage turbine nozzle 38 is
coated with tungsten carbide. The tungsten carbide coating on
second stage turbine nozzle 38 is applied using High-Velocity
Oxy-Fuel (HVOF) spraying, allowing for increased hardness and a
higher percentage of tungsten carbide as opposed to other
materials, such as cobalt.
[0044] Disk 54 is radially symmetrical about central axis 14. Full
blades 50 and splitter blades 52 are interdigitated and spaced
equidistantly from one another about the circumferential length of
disk 54. Thus, full blades 50 are each located between two adjacent
splitter blades 52, and splitter blades 52 are each located between
two adjacent full blades 50. Each of splitter blades 52, and each
of full blades 50, are equidistant radially from central axis
14.
[0045] Second stage turbine nozzle 38 is a high value component
that is relatively frequently replaced. Damage to second stage
turbine nozzle 38 may occur due to abrasive particulates in the
high velocity airflow directed by second stage turbine nozzle 38.
Thus, a highly durable coating on second stage turbine nozzle 38
may increase its service life.
[0046] HVOF coating of second stage turbine nozzle causes unique
physical characteristics that are not possible using traditional
coating technologies, such as deposition gun coating. HVOF coating
may, for example, allow for levels of tungsten carbide in excess of
91%. In addition, HVOF coating provides for surface hardness in
excess of 10,000 psi. Furthermore, HVOF coating provides for
reduced variability in surface coating thickness as compared to
detonation gun coating.
[0047] FIG. 6 is a side view of second stage turbine nozzle 38.
Second stage turbine nozzle 38 contains full blades 50, splitter
blades 52, and disk 54, as described with respect to FIG. 5.
[0048] FIG. 6 illustrates the thickness of second stage turbine
nozzle 38. In particular, second stage turbine nozzle 38 includes
blade height H38. Blade height H38 is the amount of head space
between disk 54 and an adjacent component such as a shroud (not
shown). Blade height H38 as shown in FIG. 6 is 0.940 cm (0.370 in).
In some embodiments, blade height H38 may vary by as much as 0.01
cm (0.005 in). However, blade height H38 of 0.940 cm is ideal for
the passage of the desired quantity of working fluid through second
turbine section 10 (FIG. 1).
[0049] FIG. 7 is an enlarged view of a portion of second stage
turbine nozzle 38. The enlarged portion shown in FIG. 7 shows full
blades 50 and splitter blades 52 arranged on disk 54.
[0050] FIG. 7 illustrates various specific dimensions of second
stage turbine nozzle 38. Nozzle passage width W38 is the distance
between each full blade 50 and adjacent splitter blade 52. In
effect, nozzle passage width W38 is the width of a throat through
which working air may be routed. Nozzle passage width W38 is 0.222
cm (0.0875 in), but may deviate by as much as 0.013 cm (0.005 in).
Flow area A38 is the region through which working fluid may flow.
Flow area A38 is the total cross-sectional area orthogonal to the
surface of disk 54 on the bladed side that is not covered by full
blades 50 and splitter blades 52 and through which working fluid
flows. The portion of flow area A38 identified in FIG. 7 is the
flow area A between one full blade 50 and one splitter blade 52. In
sum, over the entire surface of second stage turbine nozzle 38,
flow area A38 is 7.103 square centimeters (1.101 square inches).
Due to minor differences in machining and/or coating, this value
may be as high as 7.458 of as low as 6.748 square centimeters.
[0051] Nozzle passage width W38 is optimized to ensure proper flow
and energy extraction from second stage turbine nozzle 38.
Increasing or decreasing nozzle passage width W38 would result in
too little or too much flow through second stage turbine nozzle 38.
Likewise, flow area A38 is optimized to ensure an appropriate
quantity of working fluid is transmitted by second stage turbine
nozzle 38. A larger flow area A38 would result in too much working
fluid passing through second stage turbine nozzle 38, while a
smaller flow area A38 would result in too little.
[0052] FIG. 8 is a cross-sectional view of ACM 100. ACM 100 is a
three-wheel ACM, containing fan section 102, compressor section
104, and turbine section 106, all of which are connected to shaft
108. Shaft 108 rotates about central axis 110.
[0053] Fan section 102 includes fan inlet 112 and fan outlet 114.
Fan inlet 112 is an opening in ACM 100 that receives working fluid
from another source, such as a bleed valve in a gas turbine engine
(not shown). Fan outlet 114 allows working fluid to escape fan
section 102. Fan blades 116 may be used to draw working fluid into
fan section 102.
[0054] Compressor section 104 includes compressor inlet 118,
compressor outlet 120, and compressor nozzle 122. Compressor inlet
118 is a duct defining an aperture through which working fluid to
be compressed is received from another source, such as fan section
102. Compressor outlet 120 allows working fluid to be routed to
other systems once it has been compressed. Compressor nozzle 122 is
a nozzle section that rotates through working fluid in compressor
section 104. In particular, compressor nozzle 122 is a radial
out-flow rotor.
[0055] Turbine section 106 includes turbine inlet 124, turbine
outlet 126, and turbine nozzle 128. Turbine inlet 124 is a duct
defining an aperture through which working fluid passes prior to
expansion in turbine section 106. Turbine outlet 126 is a duct
defining an aperture through which working fluid which has expanded
departs turbine section 106. Turbine nozzle 128 is a nozzle section
that extracts energy from working fluid passing therethrough,
driving the rotation of turbine section 106 and attached
components, including shaft 108, fan section 102, and compressor
section 104.
[0056] Shaft 108 is a rod, such as a titanium tie-rod, used to
connect other components of ACM 100. Central axis 110 is an axis
with respect to which other components may be arranged.
[0057] Fan section 102 is connected to compressor section 104. In
particular, fan outlet 114 is coupled to compressor inlet 118 such
that working fluid may be transferred from fan outlet 114 to
compressor inlet 118. Working fluid is drawn through fan inlet 112
and discharged through fan outlet 114 by fan blades 116. Working
fluid from fan outlet 114 is routed to compressor inlet 118 for
compression in compressor section 104.
[0058] Similarly, compressor section 104 is coupled with first
turbine section 106. Working fluid from compressor outlet 120 is
routed to turbine inlet 124. In this way, working fluid passes
through ACM 100: first through fan inlet 112, then fan outlet 114,
compressor inlet 118, compressor outlet 120, turbine inlet 124, and
turbine outlet 126. Additional stages may exist between those shown
in FIG. 8. For example, often a heat exchanger (not shown) is
located between compressor section 104 and turbine section 106.
[0059] Each of fan section 102, compressor section 104, and turbine
section 106 are also connected to one another via shaft 108. Shaft
108 runs along central axis 110, and is connected to at least
compressor nozzle 122 and turbine nozzle 128. Fan blades 116 may
also be connected to shaft 20.
[0060] When working fluid passes through ACM 100, it is first
compressed in compressor section 104, then expanded in turbine
section 106. Often, the working fluid is also heated or cooled in a
heat exchanger (not shown) through which working fluid is routed as
it passes between compressor section 104 and turbine section 106.
Turbine section 106 to extract energy from the working fluid,
turning shaft 20 about central axis 110.
[0061] Working fluid passing through ACM 100 may be conditioned for
use in the central cabin of a vehicle powered by a gas turbine
engine. By compressing, heating, and expanding the working fluid,
it may be adjusted to a desired temperature, pressure, and/or
relative humidity. However, due to the rapid rotation of compressor
nozzle 122 and turbine nozzle 128 with respect to the working fluid
flowpath, these parts need frequent replacement.
[0062] FIG. 9 is a plan view of turbine nozzle 128 arranged about
central axis 110. Turbine nozzle 128 includes nineteen full blades
130 arranged along a surface of disk 132. Full blades 130 and disk
132 are made of a durable material such as steel, aluminum, or
titanium. Turbine nozzle 128 is coated with tungsten carbide. The
tungsten carbide coating on first stage turbine nozzle 128 is
applied using HVOF, allowing for increased hardness and a higher
percentage of tungsten carbide as opposed to other materials, such
as cobalt. HVOF spraying also results in reduced variability in
coating thickness as compared to traditional coating methods, such
as deposition gun spraying, as will be described in more detail
with respect to FIGS. 15A-15B.
[0063] Disk 132 is radially symmetrical about central axis 110.
Full blades 130 are spaced equidistantly from one another about the
circumferential length of disk 132. Each of full blades 130 are
also equidistant radially from central axis 110.
[0064] Turbine nozzle 128 is a high value component that is
relatively frequently replaced. Damage to turbine nozzle 128 may
occur due to contact with abrasive particles. Thus, a high
strength, durable coating may increase the service life of turbine
nozzle 128.
[0065] FIG. 10 is a side view of turbine nozzle 128. Turbine nozzle
128 contains full blades 130 and disk 132, as described with
respect to FIG. 9.
[0066] FIG. 10 illustrates the thickness of turbine nozzle 128. In
particular, turbine nozzle 128 includes blade height H128. Blade
height H128 is the amount of head space between disk 132 and an
adjacent component such as a shroud (not shown). In a first
embodiment, blade height H128 as shown in FIG. 10 is 0.318 cm
(0.125 in). In a second embodiment in which an increased quantity
of working fluid flow is desired, blade height H as shown in FIG.
10 may be 0.393 cm (0.155 in). In some versions of the first and
second embodiments described above, blade height H128 may vary by
as much as 0.01 cm (0.005 in.). However, blade heights H 134 of
0.318 cm or 0.393 cm are ideal for ACM 100 (FIG. 8) to pass a
desired quantity of working fluid through turbine section 106 (FIG.
8).
[0067] FIG. 11 is an enlarged view of a portion of turbine nozzle
128. The enlarged portion shown in FIG. 11 shows full blades 130
arranged on disk 132.
[0068] FIG. 11 illustrates various specific dimensions of turbine
nozzle 128. Nozzle passage width W128 is the distance between each
full blade 130 and the radially adjacent full blade 130. In effect,
nozzle passage width W128 is the width of a throat through which
working air may be routed. Nozzle passage width W128 is 0.241 cm
(0.095 in.), but may deviate by as much as 0.013 cm. (0.005 in.).
Flow area A128 is the region through which working fluid may flow.
Flow area A128 is the total surface area of disk 132 on the bladed
side through which working fluid may flow between full blades 130.
The portion of flow area A128 identified in FIG. 11 is the flow
area A between one full blade 130 and its adjacent full blade 130.
In sum, over the entire surface of turbine nozzle 128, flow area
A128 is 1.451 cm. squared (0.225 square inches) in the first
embodiment described above, and 1.806 cm. squared (0.255 square
inches) in the second embodiment described above. Due to minor
differences in machining and/or coating, these values may vary by
as much as 5%.
[0069] Nozzle passage width W128 is optimized to ensure proper flow
and energy extraction from turbine nozzle 128. Increasing or
decreasing nozzle passage width W128 would result in either too
much or too little fluid flow through nozzle 128A. Likewise, flow
area A128 is optimized to ensure an appropriate quantity of working
fluid is transmitted by first stage turbine nozzle 128. A larger
flow area A128 would result in too much working fluid passing
through turbine nozzle 128, while a smaller flow area A128 would
result in too little.
[0070] FIG. 12 is a plan view of turbine nozzle 128A, an
alternative embodiment capable of being used in three-wheel ACM
100. Turbine nozzle 128A may also be arranged about central axis
110. As with turbine nozzle 128, described above with respect to
FIGS. 8-11, turbine nozzle 128A may be used in ACM 100 (FIG. 8).
Turbine nozzle 128A includes twenty-three full blades 130A arranged
along a surface of disk 132A. Full blades 130A and disk 132A are
made of a durable material such as steel, aluminum, or titanium.
Turbine nozzle 128A is coated with tungsten carbide. The tungsten
carbide coating on turbine nozzle 128A is applied using HVOF
spraying, allowing for increased hardness and a higher percentage
of tungsten carbide as opposed to other materials, such as
cobalt.
[0071] Disk 132A is radially symmetrical about central axis 110.
Full blades 130A are spaced equidistantly from one another about
the circumferential length of disk 132A. Thus, full blades 130A are
located between two adjacent full blades 130A, and each of full
blades 130A are equidistant radially from central axis 110.
[0072] Turbine nozzle 128A is a high value component that is
relatively frequently replaced. Damage to turbine nozzle 128A may
occur due to abrasive particulates in the high velocity airflow
directed by turbine nozzle 128A. Thus, a highly durable coating on
second stage turbine nozzle 128A may increase its surface life.
[0073] FIG. 13 is a side view of turbine nozzle 128A. Turbine
nozzle 128A contains full blades 130A and disk 132A, as described
with respect to FIG. 12.
[0074] FIG. 13 illustrates the thickness of turbine nozzle 128A. In
particular, turbine nozzle 128A includes blade height H128A. Blade
height H128A is the amount of head space between disk 132A and an
adjacent component such as a shroud (not shown). Blade height H128A
as shown in FIG. 13 is 0.305 cm. (0.120 in.). In some embodiments,
blade height H128A may vary by as much as 0.01 cm. (0.005 in.).
However, blade height H128A of 0.305 cm. is ideal for the passage
of the desired quantity of working fluid through turbine section
106 (FIG. 8).
[0075] FIG. 14 is an enlarged view of a portion of turbine nozzle
128A. The enlarged portion shown in FIG. 14 shows full blades 130A
arranged on disk 132A.
[0076] FIG. 14 illustrates various specific dimensions of turbine
nozzle 128A. Nozzle passage width W128A is the distance between
each full blade 130A and its adjacent full blade 130A. In effect,
nozzle passage width W128A is the width of a throat through which
working fluid may be routed. Nozzle passage width W128A is 0.234
cm. (0.092 in.), but may deviate by as much as 0.013 cm. (0.005
cm.). Flow area A128A is the cross-sectional area through which
fluid may flow on the bladed side of disk 132A between full blades
130A. The portion of flow area A128A identified in FIG. 14 is the
flow area A between one full blade 130A and the adjacent full blade
130A. In sum, over the entire bladed surface side of disk 132A in
turbine nozzle 128A, flow area A128A is 1.639 square centimeters
(0.254 square inches). Due to minor differences in machining and/or
coating, this value may be as high as 1.721 square centimeters or
as low as 1.557 square centimeters.
[0077] Nozzle passage width W128A is optimized to ensure proper
flow and energy extraction from turbine nozzle 128A. Increasing or
decreasing nozzle passage width W128A would result in either too
much or too little fluid flow passing across turbine nozzle 128A.
Likewise, flow area A128A is optimized to ensure an appropriate
quantity of working fluid is transmitted by turbine nozzle 128A. A
larger flow area A128A would result in too much working fluid
passing through turbine nozzle 128A, while a smaller flow area
A128A would result in too little.
[0078] Each previously described turbine nozzle embodiments is
coated. The coatings are applied using HVOF. Thus, each previously
described turbine nozzle has a base made of any of a range of
acceptable base materials, such as steel, aluminum, ceramic, or
titanium. A coating is sprayed onto the base using HVOF, the
coating primarily consisting of tungsten carbide. Previously,
detonation gun coating was used to apply the coating.
[0079] The coating applied is not pure tungsten carbide. In order
to facilitate coating using detonation gun technology, the coating
is often composed of 12% cobalt, plus or minus 2%. Accordingly, the
surface coating has an adhesion strength of 8500 psi, plus or minus
5%. However, using HVOF, the coating may have a higher percentage
of tungsten carbide. A coating applied using HVOF is often composed
of 9% cobalt, plus or minus 2%. Often, the coating may contain less
than 8% cobalt by volume. Accordingly, the surface coating 164 has
an adhesion strength of 10,000 psi, plus or minus 5%.
[0080] A coating applied using detonation gun technology typically
has a minimum thickness of approximately 0.00254 cm. (0.001 in.).
These prior art coatings often have a range of approximately
0.00762 cm. (0.003 in.), plus or minus 2%. A coating applied using
HVOF will typically have a minimum thickness of approximately
0.00508 cm. (0.002 in.), and a range of 0.00508 cm. (0.002
in.).
[0081] 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.
[0082] 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.
* * * * *