U.S. patent application number 10/214547 was filed with the patent office on 2004-02-12 for pneumatic cabin super charger.
Invention is credited to Bruno, Louis J., Hipsky, Harold W., Zywiak, Thomas.
Application Number | 20040025529 10/214547 |
Document ID | / |
Family ID | 30443723 |
Filed Date | 2004-02-12 |
United States Patent
Application |
20040025529 |
Kind Code |
A1 |
Bruno, Louis J. ; et
al. |
February 12, 2004 |
PNEUMATIC CABIN SUPER CHARGER
Abstract
An aircraft air conditioning air supply system is provided that
includes a primary propulsion turbine engine having a bleed valve
providing pressurized air. A ram air inlet provides ram air. A
super charger includes a spool with at least two turbines mounted
thereon driven by the pressurized air from the engine. At least one
compressor is connected to the turbines, preferably mounted on the
same spool as the turbines, and receives the ram air. The turbines
drive the compressor and compresses the ram air for use by an air
conditioning pack. The supercharger provides compressed air to an
air conditioning pack that conditions the compressed air and
distributes the refrigerated air throughout the aircraft. The
number of turbines and compressors for the super charger is
selected by matching the specific speeds of the compressors and
turbines.
Inventors: |
Bruno, Louis J.; (Ellington,
CT) ; Zywiak, Thomas; (Suffield, CT) ; Hipsky,
Harold W.; (Willington, CT) |
Correspondence
Address: |
CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM
MI
48009
US
|
Family ID: |
30443723 |
Appl. No.: |
10/214547 |
Filed: |
August 8, 2002 |
Current U.S.
Class: |
62/402 ;
244/118.5; 62/87 |
Current CPC
Class: |
Y02T 50/56 20130101;
Y02T 50/50 20130101; B64D 2013/0618 20130101; B64D 13/06
20130101 |
Class at
Publication: |
62/402 ;
244/118.5; 62/87 |
International
Class: |
B64D 011/00; B64D
013/00; F25B 009/00; F25D 009/00 |
Claims
What is claimed is:
1. An aircraft air conditioning system comprising: a primary
propulsion turbine engine having a bleed valve providing
pressurized air; a ram air inlet providing ram air; a super charger
including a spool with at least two turbines mounted thereon and
driven by said pressurized air, and at least one compressor
connected to said turbines receiving said ram air and producing
compressed air; and an air conditioning pack receiving said
compressed air and producing refrigerated air and distributing said
refrigerated air throughout the aircraft.
2. The air conditioning system according to claim 1, wherein said
super charger includes a single spool with said at least one
compressor mounted on said single spool.
3. The air conditioning system according to claim 1, wherein said
compressor is a double entry compressor having two compressor
portions receiving approximately half of said ram air.
4. The air conditioning system according to claim 1, wherein said
super charger includes an exhaust port venting exhaust air from
said turbines and producing secondary propulsion.
5. The air conditioning system according to claim 1, wherein said
primary propulsion turbine engine includes a compressor section
with said bleed valve in communication with said compressor section
providing intermediate pressure air, and further including a fan
air bleed valve and a high pressure bleed valve each respectively
providing low and high pressure air.
6. The air conditioning system according to claim 1, wherein said
air conditioning pack is an air cycle pack.
7. The air conditioning system according to claim 1, wherein said
air conditioning pack is a vapor cycle pack.
8. The air conditioning system according to claim 1, wherein said
turbines utilize an amount of said pressurized air less than an
available amount of said pressurized air.
9. An aircraft air conditioning system comprising: a primary
propulsion turbine engine having a bleed valve providing
pressurized air; a ram air inlet providing ram air; a super charger
including a spool with at least one turbine mounted thereon and
driven by said pressurized air, and at least one compressor
connected to said turbines receiving said ram air and producing
compressed air with the number of turbines and compressors totaling
at least three; and an air conditioning pack receiving said
compressed air and producing refrigerated air and distributing said
refrigerated air throughout the aircraft.
10. The air conditioning system according to claim 9, wherein said
super charger includes at least two turbines.
11. The air conditioning system according to claim 10, wherein said
super charger includes a single spool with said at least one
compressor mounted on said single spool.
12. The air conditioning system according to claim 11, wherein said
compressor is a double entry compressor having two compressor
portions receiving approximately half of said ram air.
13. The air conditioning system according to claim 9, wherein said
super charger includes an exhaust port venting exhaust air from
said turbines and producing secondary propulsion.
14. The air conditioning system according to claim 9, wherein said
primary propulsion turbine engine includes a compressor section
with said bleed valve in communication with said compressor section
providing intermediate pressure air, and further including a fan
air bleed valve and a high pressure bleed valve each respectively
providing low and high pressure air.
15. The air conditioning system according to claim 9, wherein said
air conditioning pack is an air cycle pack
16. The air conditioning system according to claim 9, wherein said
air conditioning pack is a vapor cycle pack.
17. The air conditioning system according to claim 9, wherein said
turbines utilize an amount of said pressurized air less than an
available amount of said pressurized air.
18. A method of providing an air conditioning system super charger
comprising the steps of: a) supplying pressurized air from a
primary propulsion turbine engine; b) providing a super charger
having a number of turbines driven by a portion of the pressurized
air with the number of turbines having a first specific speed; c)
providing the super charger with a number of compressors driven by
the turbines and having a second specific speed matched to the
first specific speed; d) generating compressed air from the number
of compressors; e) supplying the compressed air to an air
conditioning pack; and f) reducing the portion of pressurized air
needed to drive the super charger with the number of turbines and
compressors.
19. The method according to claim 18, wherein the number of
turbines is two.
20. The method according to claim 19, wherein the number of
compressors is one.
21. The method according to claim 18, wherein the total number of
turbines and compressors is at least three.
22. The method according to claim 18, wherein matching said first
and second specific speeds includes c1) determining a first and
second efficiency respectively for the number of turbines and
compressors, and c2) balancing the efficiencies to achieve a
desired level of compressed air for the air conditioning pack.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to an air conditioning system for an
aircraft, and more particularly, the invention relates to a
pneumatic cabin super charger.
[0002] Aircraft engine designs typically employ bleed ports that
pipe air to air supply systems or bleed systems that provide
compressed air to an air conditioning system. An environmental
control system (ECS) distributes the conditioned air throughout the
aircraft. In the 1960's the Convair 880 utilized a super charger
having a single compressor and a single turbine to provide
compressed air for the air conditioning system.
[0003] Typically, one of the engine bleed ports provides fan air to
cool the bleed air supplied to the air conditioning system. An
intermediate pressure bleed port provides air for the air
conditioning system to ventilate and cool the aircraft cabin during
normal flight. A high pressure bleed air port ventilates and cools
the aircraft cabin during ground idle and aircraft descent. The
intermediate pressure bleed port location is typically located on
the engine such that sufficient air pressure is provided for a
scenario referred to as "hot day, end of cruise", which simulates a
worse case scenario for aircraft ventilation. As a result, the
intermediate pressure bleed port exceeds the ECS pressure
requirements during a typical standard day cruise. Typically, the
ECS only requires approximately 30 psi of air pressure. At the
standard day cruise condition the bleed port provides a pressure
much higher than 30 psi, sometimes as much as 40-90 psi, and a
pressure regulator must be employed to throttle the intermediate
pressure bleed air to the desired air pressure.
[0004] As a result, bleed air is provided at a much higher pressure
than is typically required and the engine efficiency is reduced.
Other alternatives have been proposed to increase the efficiency of
the engine such as taking air from the lower pressure sections of
the engine compressor. However, such alternatives are not feasible
because the compressor sections typically contain variable geometry
and guide vanes that make such a system undesirable. Therefore,
what is needed, is an air conditioning system and super charger
that reduces the air pressure bled from the engine and increases
overall engine efficiency.
SUMMARY OF THE INVENTION AND ADVANTAGES
[0005] The present invention provides an aircraft air conditioning
air supply system including a primary propulsion turbine engine
having a bleed valve providing pressurized air. A ram air inlet
provides ram air. A super charger includes a spool with at least
two turbines mounted thereon driven by the pressurized air from the
engine. At least one compressor is connected to the turbines,
preferably mounted on the same spool as the turbines, and receives
the ram air. The turbines drive the compressor and compresses the
ram air for use by an air conditioning pack. The supercharger
provides compressed air to the air conditioning pack. The air
conditioning pack provides refrigerated air that is distributed
throughout the aircraft.
[0006] The number of turbines and compressors for the super charger
is selected by matching the specific speeds of the compressors and
turbines. The specific speed is indicative of the efficiency of the
compressor and turbine and provides an overall efficiency of the
super charger. Of course, the number of turbines and compressors
dictates the cost of the super charger and is balanced against the
increased efficiency from the engine due to the reduced amount of
bleed air required for the super charger.
[0007] Accordingly, the above invention provides an air
conditioning system and super charger that reduces the air pressure
bled from the engine and increases the overall engine
efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Other advantages of the present invention can be understood
by reference to the following detailed description when considered
in connection with the accompanying drawings wherein:
[0009] FIG. 1 is a schematic view of the air conditioning system of
the present invention;
[0010] FIG. 2 is a graph of the specific speed versus maximum
efficiency for a compressor; and
[0011] FIG. 3 is a graph of the specific speed versus maximum
efficiency of two turbines.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] An air conditioning system 10 is shown schematically in FIG.
1. The system 10 includes a primary propulsion engine 12 utilized
to propel the aircraft. The engine 12 typically includes several
bleed ports that provide bleed air to various components of the
aircraft and are located along the engine in such a manner so as to
provide a desired amount of air pressure. For example, a compressor
section 14 of the engine 12 includes a fan bleed air valve 16 that
is used to provide air to cool the bleed air valves. A high
pressure bleed valve is used to provide higher pressure air to
those aircraft components requiring high pressure air. An
intermediate pressure bleed valve 20 provides intermediate pressure
air, which is typically used for air conditioning of the
aircraft.
[0013] Bleed air from the valve 20 may be as high as 40-90 psi,
although the air conditioning system typically only requires air
pressure of approximately 30 psi. The present invention
incorporates a super charger 22 configured such that a reduced
amount of bleed air is required from the engine thereby increasing
the overall efficiency of the engine. The present invention
supercharger 22 includes a turbine section 24 driving a compressor
section 26. Preferably, a single spool 28 includes at least two
turbines 30, preferably two turbines, and compressor portions 32
mounted on the spool 28. The configuration of the compressor
portions 32 shown in FIG. 1 depicts a double entry compressor,
although other compressor configurations may be used. Ram air
enters from a ram air source 36 into the compressor portions 32 to
provide compressed air to the a/c pack 38. The double entry
compressor shown reduces the amount of ram air entering each
compressor portion 32 by half, which permits the compressor to run
more efficiently at increased speeds.
[0014] The turbines 30 may includes an exhaust port 34 that
exhausts the air compressed by the turbine to provide supplemental
propulsion to the aircraft. A particular set of turbines or
compressor portions will have a specific speed corresponding to a
particular efficiency of that component. Specific speed is widely
used in fluid mechanics to relate efficiency to speed regardless of
the dimensions of the turbine or compressor.
[0015] Since the turbine and compressor are mounted on a single
spool 28 rotating at a particular speed, the compressor and turbine
must be matched to attain a desired turbine and compressor
efficiency. The number of turbines and compressors may be selected
to obtain a particular specific speed, and accordingly, a
particular component efficiency. Typically, increasing the number
of turbines and compressors increases the efficiency of the super
charger 22. However, an increased number of compressors or turbines
may significantly increase the overall cost of the super charger.
This increased cost must be balanced against the increased
efficiency obtained from the engine 12. The Applicants have
determined that a super charger may preferably include two turbines
30 and a compressor, which may be a double entry compressor, to
provide a reasonable super charger cost based upon the increase in
engine efficiency that may be achieved.
[0016] The compressed air from the compressor portions 32 is
changed to refrigerated air in the A/C pack 38 through a
refrigeration cycle which is then provided for distribution
throughout the aircraft cabin 40. The A/C pack may be an air or
vapor cycle pack.
[0017] The invention has been described in an illustrative manner,
and it is to be understood that the terminology that has been used
is intended to be in the nature of words of description rather than
of limitation. Obviously, many modifications and variations of the
present invention 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 as
specifically described.
* * * * *