Air management system

Abstract

An air management system with a set of compressed air sources for supplying pressurized air to air consumer equipment. In particular, either an air bleed system, electrical compressors, or a combination thereof may perform such supplying of compressed air depending on the aircraft operation condition.

Claims

1. A method for supplying pressurized air to air consumer equipment, the method comprising: providing an air management system comprising: at least one air consumer; at least one air source; at least one gas turbine engine having a single bleed air port, the single bleed air port located at a low-intermediate compressor stage of the at least one gas turbine engine; an air bleed system in fluid communication with the at least one gas turbine engine via the single bleed air port of the at least one gas turbine engine, the air bleed system being configured to supply compressed air to the at least one air consumer; at least one electrical compressor in fluid communication with the at least one air source, the at least one electrical compressor being configured to supply compressed air to the at least one air consumer; and a controller configured to receive an input relative to an aircraft operation condition and selectively operate at least one of the air bleed system and the at least one electrical compressor based on the received input; receiving by the controller the input relative to the aircraft operation condition; operating at least one of the air bleed system and the at least one electrical compressor based on the received input; and operating by the controller at least one of the air bleed system and the at least one electrical compressor, depending on the received input, so that: in taxiing, the at least one electrical compressor supplies the compressed air to the at least one air consumer; in taking-off, the at least one electrical compressor supplies the compressed air to the at least one air consumer; in the climb, the at least one electrical compressor supplies the compressed air to the at least one air consumer up to the pre-determined altitude; then, the air bleed system supplies the compressed air to the at least one air consumer; in the cruise, the air bleed system supplies the compressed air to the at least one air consumer; and in descent, holding, and landing, the at least one electrical compressor supplies the compressed air to the at least one air consumer.

2. The method according to claim 1, wherein the at least one air consumer of the air management system is at least one of the following: an environmental control system; a fuel tank inerting system; a wing anti-ice system; an engine starting system; a water and waste system; and hydraulic reservoirs pressurization.

3. An method according to claim 2, wherein the environmental control system comprises a vapor cycle machine configured to be operated by at least one of the air bleed system and the at least one electrical compressor.

4. The method according to claim 2, wherein the wing anti-ice system is electrical.

5. The method according to claim 1, wherein the air bleed system further comprises a pre-cooler dimensioned to operate with bleed air extracted from the single bleed air port at the low-intermediate compressor stage.

6. The method according to claim 1, wherein the aircraft operation condition is at least one of a pre-determined flight altitude and a flight phase among the following: the taxiing, the take-off, the climb, the cruise, the descent, the holding and the landing.

7. The method according to claim 6, wherein an architecture of the air bleed system is sized according to cruise phase flight conditions.

8. The method according to claim 1, wherein the at least one electrical compressor is configured to adapt the supplied compressed air according to at least one of the flight phase and an aircraft flight altitude.

9. The method according to claim 1, wherein the air bleed system is in fluid communication with each of the at least one gas turbine engine of the aircraft via a respective single bleed air port located at a respective low-intermediate compressor stage of each gas turbine engine, and the at least one electrical compressor comprises two electrical compressors.

10. The method according to claim 1, wherein the at least one electrical compressor is interposed between the air bleed system and the at least one air consumer, so that the air bleed system is the air source of the at least one electrical compressor.

11. The method to claim 1, further comprising an energy storage device configured to supply power to the at least one electrical compressor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and other characteristics and advantages of the invention will become clearly understood in view of the detailed description of the invention which becomes apparent from a preferred embodiment of the invention, given just as an example and not being limited thereto, with reference to the drawings.

(2) FIG. 1 shows a schematic graph of a conventional IP, HP air bleed system power delivering in comparison with power required by air consumers.

(3) FIGS. 2a-b show a schematic representation of an aircraft comprising (a) a conventional air management system, and (b) an air management system according to the present invention.

(4) FIGS. 3a-b show a schematic architecture of (a) a conventional air management system, and (b) an air management system according to the present invention.

(5) FIG. 4 shows a schematic representation of an aircraft mission profile using an air management system according to the present invention throughout the flight phases.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(6) As it will be appreciated by one skilled in the art, aspects of the present invention may be embodied as an air management system, a method, a data processing apparatus, a computer program, or an aircraft.

(7) FIG. 1 depicts a schematic graph (7) of a conventional IP-HP air bleed system power delivering (7.1) in comparison with power required (7.2) by air consumers throughout a complete flight.

(8) As it can be seen, it is compared the power required (7.2) by air consumers in kW vs. the power delivered (7.1) by conventional IP-HP air bleed system (in kW). Superimposed on the former, there is an overview of the flight phases (7.3) through which aircraft passes in a complete flight, in particular taking altitude as a reference to place the aircraft in each of such flight phases.

(9) In this exemplary mission profile, there is a mismatch between power supplied by the air bleed system and required by the air consumers both at the beginning and end of the flight, that is, in principle when aircraft is on-ground or close to it below a certain flight altitude.

(10) Left-ordinate axis of the graph indicates power (in kW), while right-ordinate axis indicates flight altitude (in ft.). Finally, abscissa axis refers to flight time (in minutes).

(11) Typical IP-HP air bleed system is conventionally designed as follows:

(12) IP port extracts air during take-off, climbing, cruise, and holding; and

(13) HP port extracts air on-ground, during descent and even holding if IP port is not capable of providing enough air pressure to meet air consumer requirements.

(14) Therefore, in those phases where HP port is extracting air to supply air consumers, there is a significant energy loss as it can be seen by peaks (7.4) in the graph (selected by dashed circles). Those peaks (7.4) represent a power mismatch which entails an energy loss.

(15) This energy loss is because:

(16) on one hand, the energy delivered by the HP port during holding is significantly higher than the energy required by air consumers. HP port is used under these conditions because the energy delivered by the IP port is lower than the energy required; and

(17) the energy delivered by the IP port during take-off and early climb phases is significantly higher than the energy required, since the IP port is selected to meet the requirements of the air consumers during cruise. Further, in cruise, the energy extracted from the IP port is lower than during take-off and climbing phases.

(18) FIG. 2a depicts a schematic representation of an aircraft comprising a conventional air management system exclusively based on air bleed system (2).

(19) In particular, the aircraft (10) comprises two gas turbine engines (4) hanging from each wing by respective pylons. It is schematically represented the ducting or channeling from the two ports, IP (2.1) and HP (2.2), coming from different compressor stages of the gas turbine engines (4). It is to be noted that valves, and other hydraulic equipment are not shown in these figures.

(20) It is shown that bleed ports (IP and HP) are in fluid communication (by channels or ducts (2.1.1, 2.2.1)) with WAIS (5.3) and Air Conditioning Packs (5.1) of the ECS in order to convey pressurized air thereto.

(21) Furthermore, the aircraft (10) comprises an Auxiliary Power Unit (‘APU’) (6) at the tailcone of the aircraft (10). This APU (6) is also in fluid communication (by APU bleed ducting (6.1)) with the WAIS (5.3) and Air Conditioning Packs (5.1) of the ECS in order to provide either pneumatic or electrical energy thereto.

(22) Typical APU bleed ducting (6.1) for pneumatic mode is also associated with OverHeat Detection System for safety reasons.

(23) On the other hand, FIG. 2b depicts an example of a schematic representation of a similar aircraft (10) as the one shown in FIG. 2a but comprising an air management system (1) according to the present invention.

(24) Instead of IP-HP port for each gas turbine engine (4) as shown in FIG. 2a, the air bleed system (2) according to the present invention only extracts air from a single port, which is in fluid connection with the Air Conditioning Packs (5.1) of the ECS. In this particular embodiment, the Air Conditioning Packs are replaced by Vapor Cycle Machine Packs (5.2) which need lower air pressure in comparison with conventional Air Conditioning Packs (5.1).

(25) Further, two electrical compressors (3) are positioned within the belly fairing of the aircraft (10) along with the Air Conditioning Packs or Vapor Cycle Machine Packs of the ECS.

(26) In particular embodiments, the wing anti-ice system (‘WAIS’) may be electrical (5.4) so the ducting for conveying pressured air is no longer needed. Instead, wiring connections (which are lighter than ducts) should be deployed.

(27) Similarly, APU bleed ducting (6.1) is deleted since pneumatic mode is no longer needed. Only electrical mode for supplying power to the electrical compressor (3), for instance, is envisaged. Besides, other power consumers such as batteries, electrical WAIS (5.4), or the like, may be supplied by the APU (6) running in electric mode (or any other electric source).

(28) Deletion of APU bleed ducting (6.1) (that is, APU only works in ‘electrical mode’) bring the following advantages along:

(29) Significant weight reduction, around 170 kg. (in a short-range aircraft (10)).

(30) Removal of the harmful installation of a high pressure and temperature duct running through the pressurized fuselage.

(31) Deletion of OHDS associated to the APU ducting.

(32) The formerly needed surplus of compressed air provided by the APU (6) is, within the present invention, exclusively provided by the air bleed system (2) through the single port (e.g., IP) after optimization and modelling works. This can be easily done by the person skilled in the art knowing temperature and pressure constraints of the air management system (1) channels, with the aim to meet air consumers (5) requirements acknowledged beforehand.

(33) For example, the combination of electrical WAIS (5.4) and Vapor Cycle Machine Packs (5.2) in the ECS permits reducing by 2 or 3 compressor stages the location of the single port due to low pressure requirement of Vapor Cycle Machine packs above 15000 ft. (8 to 12 psig nominal conditions and up to 14 psig in failure cases).

(34) It is to be noted that, although only WAIS (5.3, 5.4) and ECS (5.1, 5.2) are represented as air consumers (5), other minor air consumers may be used such as: fuel tank inerting system, engine starting system, water and waste, and/or hydraulic reservoirs pressurization.

(35) Also, a control unit (controller (8)) is electrically connected to both the air bleed system (2) and the electrical compressor(s) (3) to selectively operate them based on an aircraft (10) operational condition. In particular, the control unit (8) is electrically connected to some valves of the air bleed system (2) to allow the bleed air coming from the single port either to pass through, or being cut-off, or the flow rate being reduced.

(36) Particularly, such aircraft (10) operation condition may be a pre-determined flight altitude, for instance 15000 ft., and/or any of the flight phases seen in FIG. 4.

(37) FIG. 3a depicts a schematic architecture of a conventional air management system (1). In particular, it may be the hydraulic scheme of a portion of the air management system (1) shown in FIG. 2a.

(38) It can be appreciated the two ports, IP (2.1) and HP (2.2), coming from the compressor stage of the gas turbine engine (4). Additionally, there is a third port (2.3) in fluid communication with the fan, specifically design to extract cooling air therefrom and direct it to a pre-cooler (2.4).

(39) This pre-cooler (2.4) is designed to operate with the bleed air extracted from any of the two ports (IP and HP) at respective compressor stages. Therefore, since bleed air extracted from HP (2.2) has higher pressure and temperature, the pre-cooler (2.4) has bigger size to increase the cooling effect. Pre-coolers are normally integrated within the pylon.

(40) Alternatively, cooling air may directly come from ram air instead from fan port (2.3).

(41) It can be seen also the valves, regulators, and other hydraulic components which forms the air management system (1) of the aircraft (10). For instance, there is a overpressure valve (‘OPV’) (2.5), also named as relief valves, or High Pressure Valve (‘HPV’) (2.6) whose function is to maintain the pressurized air conveyed through ducting (2.2.1) at an admissible pressure and temperature.

(42) FIG. 3b depicts a schematic architecture of an air management system (1) according to the present invention. As an example, it may form the pneumatic scheme of a portion of the air management system (1) shown in FIG. 2b.

(43) In comparison with the conventional hydraulic scheme of FIG. 3a, the pneumatic scheme of an air management system (1) according to the present invention is substantially similar in lay-out, but HP ducting (2.2.1) sections and related valves (2.2, 2.5, 2.6) are no longer shown. These deleted elements are shown struck through.

(44) In particular, HP port (2.2) (that is, the port located at a higher compressor stage) is deleted. The associated High Pressure Valve (HPV) (2.6) has been also deleted since the air extracted from the remaining IP port (2.1) does not reach such a high temperature and pressure.

(45) Air extracted from the remaining IP port (2.1) is controlled via the Pressure Regulating Valve (‘PRV’).

(46) The valve (‘IPCV’) interposed between IP port and the joining point where formerly IP ducting and HP ducting were brought together (to avoid, inter alia, reverse flow) is still of application to shut-off the flow of extracted air form remaining IP port (2.1). Nevertheless, in particular embodiments, IPCV may be deleted as there is no risk of reverse flow in the IP port of air coming from the HP port as prior art pneumatic schemes do.

(47) Further, former Over-Pressure Valve (2.5) is no longer needed as maximum IP port pressure remains below 90 psig within the present invention.

(48) Only one port, IP port (2.1) coming from the compressor stage of the gas turbine engine is appreciated. Additionally, there is a third port (2.3) in fluid communication with the fan, specifically designed to extract cooling air therefrom and direct it to a pre-cooler (2.4).

(49) Since air reaching the pre-cooler (2.4) from the hot side (that is, from the IP duct) is not as hot as with the conventional HP port (2.2) of the air bleed system, pre-cooler is specifically designed to operate with the bleed air extracted from the single port (i.e., the IP port). This entails a pre-cooler size reduction of about 50%.

(50) Once the IP compressed air has been cooled down in the pre-cooler, it is directed to the air consumers (5) as the arrow points out.

(51) It is to be noted that the present air management system (1) regulates conveyed air at around 80° C.-100° C. contrary to nowadays temperature regulation (IP-HP bleed systems) at 200° C.

(52) Further, single port (2.1) (IP port) location is reduced by 2-3 stages because low pressure requirement of Vapor Cycle Machine Packs (5.2) above 15000 ft., although not shown herein for illustrative purposes.

(53) The present invention further provides a method for supplying pressurized air to the air consumer (5) equipment. Briefly, the steps of the method are as follows:

(54) providing an air management system (1) as described hereinabove;

(55) receiving by the control unit (controller (8)) an input relative to the aircraft (10) operation condition; and

(56) operating the air bleed system (2) and/or the at least one electrical compressor (3) based on the received input.

(57) FIG. 4 depicts an exemplary aircraft (10) mission profile using an air management system (1) according to the present invention throughout the flight phases.

(58) If the at least one electrical compressor (3) supplies compressed air to at least one air consumer (5), it is represented in a continuous line. On the other hand, when the air bleed system (2) exclusively supplies compressed air to the at least one air consumer; it is represented in a dashed line.

(59) It is to be noted that, for illustrative purposes, no overlap between operation of the air bleed system (2) and operation of the at least one electrical compressor (3) is shown, but this situation of overlap is of interest at the interphase when compressed air source (2, 3) switches.

(60) In particular, the criteria follow by the control unit (8) to operate the air bleed system (2) and/or the at least one electrical compressor (3) upon receiving an aircraft (10) operation condition (i.e., flight altitude or flight phase) is summarized as follows:

(61) Below a pre-determined altitude, preferably 15000 ft.:

(62) in taxiing, the at least one electrical compressor (3) supplies compressed air to at least one air consumer (5);

(63) in taking-off, the at least one electrical compressor (3) supplies compressed air to at least one air consumer (5);

(64) in climbing, the at least one electrical compressor (3) supplies compressed air to at least one air consumer (5) up to the pre-determined altitude;

(65) Above the pre-determined altitude:

(66) still in climbing, the air bleed system (2) exclusively supplies compressed air to the at least one air consumer (5);

(67) in cruise, the air bleed system (2) supplies compressed air to at least one air consumer (5); and

(68) Once cruise phase ends:

(69) in descending, holding, and landing, the at least one electrical compressor (3) supplies compressed air to at least one air consumer (5).

(70) In other words, as the aircraft (10) passes from one phase to another, the control unit (8) receives the corresponding input and operates the corresponding compressed air source (bleed air system (2) and/or electrical compressor (3)) via the corresponding valves or directly by the electrical compressor.

(71) As it was already mentioned, since air bleed system (2) exclusively operates in favorable conditions from energy cost point of view (high altitude and relative high speed), the air bleed system (2) architecture is sized according to cruise phase flight conditions, which encompasses the majority of the flight.

(72) Energy-demanding flight phases such as on-ground operation, take-off, or even the first portion of climbing, as well as other phases like descent (or approaching) and holding relies exclusively in pressurized air supplied by the electrical compressor(s).

(73) Therefore, the electrical compressor(s) (3) adapts the delivered pressure to the required pressure by the air consumer (5) upon indication from the control unit (8).

(74) Throughout the entire description, the person skilled in the art would recognize that specific figures of aircraft (10) operation, or parameters of air bleed systems highly depend on specifics of the aircraft (10) model.

(75) While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.