Autonomous aircraft cabin energy recovery module and corresponding method

Abstract

The invention relates to a module (23) for recovery of energy of an aircraft cabin (5) comprising at least one air outlet (16) from the cabin and at least one fresh air inlet (15) into the cabin, the said module comprising: a turbine engine (30) comprising a compressor (31) and a turbine (32) mechanically coupled to one another; a cabin-air recovery duct (42) designed to be able to link the air outlet (16) from the cabin and the said turbine (32); a cabin-air injection duct (41) designed to be able to link the compressor (31) and fresh air inlet (15) into the cabin; an emergency duct (43) designed to be able to link a high-pressure air source and the said turbine (32); a control unit (25) configured to be able, according to predetermined operational conditions, to activate either a routine mode, in which the said turbine (32) is exclusively supplied by the air evacuated from the cabin (5), or an emergency mode, in which the said turbine (32) is exclusively supplied by the air provided by the high-pressure air source.

Claims

1. A module for recovery of energy of an aircraft cabin comprising at least one air outlet from the cabin and at least one fresh air inlet into the cabin, designed to be supplied by an environmental control system of the cabin, the module comprising: a turbine engine comprising at least one compressor equipped with an air inlet and an air outlet, and at least one turbine equipped with an air inlet and an air outlet which are mechanically coupled to one another, a duct, called cabin-air recovery duct, designed to be able to link in fluid communication an air outlet from the cabin and an air inlet of the said turbine, the said cabin-air recovery duct moreover being equipped with an air flow control valve, called recovery valve, a duct, called compressor supply duct, designed to be able to link in fluid communication an outside-air bleed device and an air inlet of the compressor, a duct, called cabin-air injection duct, designed to be able to link in fluid communication an air outlet of the compressor and a fresh air inlet into the cabin, a duct, called emergency duct, designed to be able to link in fluid communication a high-pressure air source and an inlet of the turbine, the said emergency duct moreover being equipped with an air pressure control valve, called emergency valve, a control unit for the said recovery valve and the said emergency valve, configured, according to predetermined operational conditions, to be able to activate at least one of the following modes of operation: a routine mode, in which the said recovery valve is open and the said emergency valve is closed, in such a manner that the said turbine is exclusively supplied by the air evacuated from the cabin, an emergency mode, in which the said recovery valve is closed and the said emergency valve is open, in such a manner that the said turbine is exclusively supplied by the air provided by the high-pressure air source.

2. The module according to claim 1, further comprising a heat exchanger designed to ensure heat exchanges between the air flow conveyed by the said cabin-air recovery duct and the air flow conveyed by the said cabin-air injection duct, and in that the said emergency duct leads into the said cabin-air recovery duct downstream of the said recovery valve and upstream of the said heat exchanger.

3. The module according to claim 1, said control unit is configured to be able to activate, according to predetermined operational conditions, an intermediary mode, in which the recovery valve and emergency valve are jointly controlled upon opening, in such a manner that the said turbine is jointly supplied by the air evacuated from the cabin and the air provided by the high-pressure air source.

4. The module according to claim 1 wherein the predetermined operational conditions enable a definition of the routine and emergency modes of operation of the said module, depending on the said environmental control system of the aircraft cabin.

5. The module according to claim 1 further comprising a three-way valve that simultaneously forms the said recovery valve and the said emergency valve.

6. The module according to claim 1 wherein the high-pressure air source is an air bleed device of a compressor of a propulsion engine of the aircraft.

7. The module according to claim 1 wherein the emergency duct is equipped with a pressure regulation device in such a manner to adapt the pressure of the air supplied to the said turbine, to the technical specifications of the said turbine.

8. The module according to claim 1 further comprising a duct, called a turbine outlet duct, designed to be able to link in communication an air outlet of the turbine of the turbine engine and an air outlet outside of the aircraft in such a manner to be able to expel the expanded air outside of the aircraft.

9. The module according to claim 1 the said turbine engine is a turbine engine that has at least two turbine stages in parallel.

10. A process for recovery of energy of an aircraft cabin comprising at least one air outlet from the cabin and at least one fresh air inlet into the cabin, which inlet is designed to be supplied by an environmental control system of the cabin, the processing comprising linking an air inlet of a turbine of a turbine engine in fluid communication to an outlet for air from the cabin by means of a duct, called cabin-air recovery duct, equipped with an air flow control valve, called recovery valve, linking an air inlet of a compressor of the said turbine engine in fluid communication to an outside air bleed device by means of a duct, called compressor supply duct, linking an air outlet of the said compressor on fluid communication to a fresh air inlet of the cabin by means of a duct, called cabin-air injection duct, linking a high-pressure air source in fluid communication to the said air inlet of the turbine by means of a duct, called emergency duct , equipped with an air pressure control valve, called emergency valve, wherein the recovery valve and the said emergency valve are controlled to be able, according to predetermined operational conditions, to ensure at least the following modes of operation: a routine mode, in which the said recovery valve is open and the said emergency valve is closed, in such a manner that the said turbine is exclusively supplied by the air evacuated from the cabin, an emergency mode, in which the said recovery valve is closed and the said emergency valve is open, in such a manner that the said turbine is exclusively supplied by the air provided by the high-pressure air source.

11. The process according to claim 10, wherein that heat exchanges are ensured between the air flow conveyed by the said cabin-air recovery duct and the air flow conveyed by the said cabin-air injection duct by means of a heat exchanger, and in that the said emergency duct leads into the said cabin-air recovery duct downstream of the said recovery valve and upstream of the said heat exchanger.

12. An environmental control system of an aircraft cabin comprising at least one air outlet from the cabin and at least one fresh air inlet into the cabin, the said system comprising at least one air conditioning pack designed to provide conditioned air to a fresh air inlet of the cabin, the system further comprising a module for recovery of energy the module comprising: a turbine engine comprising at least one compressor equipped with an air inlet and an air outlet, and at least one turbine equipped with an air inlet and an air outlet which are mechanically coupled to one another, a duct, called cabin-air recovery duct, designed to be able to link in fluid communication an air outlet from the cabin and an air inlet of the said turbine, the said cabin-air recovery duct moreover being equipped with an air flow control valve, called recovery valve, a duct, called compressor supply duct, designed to be able to link in fluid communication an outside-air bleed device and an air inlet of the compressor, a duct, called cabin-air injection duct, designed to be able to link in fluid communication an air outlet of the compressor and a fresh air inlet into the cabin, a duct, called emergency duct, designed to be able to link in fluid communication a high-pressure air source and an inlet of the turbine, the said emergency duct moreover being equipped with an air pressure control valve, called emergency valve, a control unit for the said recovery valve and the said emergency valve, configured, according to predetermined operational conditions, to be able to activate at least one of the following modes of operation: a routine mode, in which the said recovery valve is open and the said emergency valve is closed, in such a manner that the said turbine is exclusively supplied by the air evacuated from the cabin, a emergency mode, in which the said recovery valve is closed and the said emergency valve is open, in such a manner that the said turbine is exclusively supplied by the air provided by the high-pressure air source.

Description

5. LIST OF THE FIGURES

(1) Other objectives, features and advantages of the invention will be apparent upon reading the following description, which is provided merely as a non-limiting example and refers to the appended figures, in which: FIG. 1 is a schematic view of a module for recovery of energy according to an embodiment of the invention, FIG. 2 is a schematic view of an environmental control system according to an embodiment of the invention.

6. DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION

(2) FIG. 1 schematically represents an aircraft comprising a passenger cabin 5, and at least one main engine 3. This main engine 3 intended for the propulsion of the aircraft comprises, for example, a compressor 11 and a turbine (not represented in FIG. 1).

(3) FIG. 1 likewise illustrates an air conditioning pack 55, better known by the acronym ECS. This conditioning pack 55 can have various embodiments, one of which is schematically represented in FIG. 2. The air conditioning pack 55 that is schematically represented in FIG. 2 is a pack, the architecture of which uses predominantly pneumatic means. It should nonetheless be noted that the invention likewise relates to an electric air conditioning pack or to a hybrid electro-pneumatic air conditioning pack.

(4) FIG. 1 illustrates a module 23 for recovery according to an embodiment of the invention. This module 23 for recovery of energy according to the invention comprises a turbine engine 30 comprising a compressor 31 and a turbine 32 that are mechanically coupled to one another.

(5) The compressor 31 comprises an air inlet 31a linked in fluid communication to an outside air scoop 70 by means of a compressor supply duct 40, and an air outlet 31b linked in fluid communication to a fresh air inlet 15 into the cabin 5 by means of a cabin-air injection duct 41.

(6) The turbine 32 comprises an air inlet 32a linked in fluid communication to an air outlet 16 from the cabin 5 by means of a cabin-air recovery duct 42. This duct 42 is equipped with an air flow control valve, called recovery valve 52. This recovery valve 52 can be an air flow control valve.

(7) The air inlet 32a of the turbine is likewise linked in fluid communication to the said compressor 11 of the propulsion engine 3 by means of an emergency duct 43. This emergency duct 43 is equipped with an air pressure control valve, called emergency valve 53. This emergency valve 53 is, for example, associated with a pressure sensor housed in the emergency valve in such a manner as to be able to provide pressure measurements downstream of the valve 53 allowing the emergency valve to regulate the air pressure provided to the turbine of the turbine engine.

(8) The turbine 32 likewise comprises an air outlet 32b linked in fluid communication to an outside air outlet 57 by means of a turbine outlet duct 44.

(9) The module 23 for recovery of energy likewise comprises a heat exchanger 75 designed to ensure heat exchanges between the flow of air conveyed by the cabin-air recovery duct 42 and the flow of air conveyed by the cabin-air injection duct 41. This heat exchanger 75, better known as an intercooler, allows for the recovery of the heat energy at the outlet from the compressor 31 to increase the temperature and thus the energy at the inlet to the turbine 32. Moreover, this heat exchanger 75 allows for an air temperature at the outlet from the module 23 for recovery of energy which approaches the temperature of the cabin 5 air. In other words, the heat exchanger 75 allows for the auto-stabilisation of the temperature of the air compressed by the compressor 31.

(10) The module 23 for recovery of energy lastly comprises a control unit 25 for the recovery valve 52 and the emergency valve 53.

(11) This control unit 25 can be of any type and depends on the type of control valve used.

(12) The control unit 25 is configured in order to be able to control the opening/closing of each of the two valves in such a manner to be able to control the supply of the turbine 32, either by the air evacuated from the cabin (routine mode), or by the high-pressure air provided by the compressor 11 of the propulsion engine 3 of the aircraft (emergency mode).

(13) The control unit can likewise control the simultaneous opening of the two valves in such a manner as to supply the turbine 32 at the same time with air evacuated from the cabin and with the high-pressure air derived from the compressor 11 of the propulsion engine.

(14) The module 23 according to the embodiment of FIG. 1 likewise comprises a flap 51 arranged on the duct 41 for injecting air into the cabin.

(15) A module 23 according to the invention is autonomous in such a manner that it can be directly connected between the air outlet (16) from the cabin and the fresh air inlet 15 into the cabin. Preferably, the air outlet (16) and the air inlet 15 are each equipped with a controllable valve (not represented in the figures). These valves are generally provided on all aircrafts in order to allow the renewal of the air in the cabin 5 and the control of the predominant pressure in the cabin. These cabin inlet and outlet valves are controlled by a logic for controlling the pressurisation of the cabin 5 based upon the different flight phases and the conditions of use of the cabin, in particular the number of passengers in the cabin.

(16) Preferably, the module 23 is associated with the air conditioning pack 55 of the aircraft. To this end, the supply duct 41 of the cabin supplies a mixing chamber 36 which is likewise supplied by the air provided by the air conditioning pack 55. This mixing chamber 36 allows the receipt of the air flows provided on the one hand by the air conditioning pack 55 and, on the other hand, by the cabin-module 23 for recovery of energy, and the mixing thereof prior to their introduction into the cabin 5. This mixing chamber 36 is supplied by a duct which receives the two air flows. This duct preferably comprises a check valve 50.

(17) FIG. 2 represents the air conditioning pack 55 in a more detailed manner and, in a less detailed manner, the module 23 for recovery of cabin-energy.

(18) An air conditioning pack, better known as an ECS or Environmental Control System, can be made up of an assembly of mechanisms which are enclosed in a casing or housing and have air inlet and outlet connection ports and a channel for the circulation of dynamic air, better known by the term air RAM, by means of one or more heat exchangers. Such a pack can be the object of numerous embodiment variants which are compatible with a module for recovery of energy according to the invention. FIG. 2 schematically illustrates one of the possible embodiment variants.

(19) Such a pack comprises, and as represented in FIG. 2, at least one air cycle turbine engine 20 which comprises, according to the embodiment of FIG. 2, a compressor 21 and a turbine 22 linked to one another by a rotating shaft 19. The turbine engine likewise comprises a fan 18 configured so as to ensure the circulation of dynamic air, known by the acronym RAM, through heat exchangers. According to the embodiment shown in the figure, the fan 18 is fitted to the rotating shaft 19 linking the compressor 21 and the turbine 22. According to another embodiment, the fan can be rotatably driven by other means, such as, for example, electrical means.

(20) According to a variant that is not represented in the figures, the outlet duct 44 of the turbine of the module 23 leads into a dynamic-air circulation channel of the air conditioning pack 55.

(21) The pack likewise comprises a water extraction loop 64 (not represented in detail for the purpose of clarity) that is well known to the person skilled in the art.

(22) The air conditioning pack 55 is supplied with air bleed from the compressor 11 of the engine 3 by means of an air bleed duct 45, and the pack 55 supplies the cabin 5 by means of a cabin inlet duct 46. The bleed duct 45 is equipped with a valve 59 controlled by a control logic of the air conditioning pack 55 in such a manner to be able to adapt the air flow and/or pressure provided to the pack as required.

(23) A first circuit of an air/air heat exchanger 62 is located between the outlet of the compressor 21 and the inlet of the turbine 22 in such a manner to be able to cool the compressed and reheated air delivered by the compressor 21 prior to its introduction into the air inlet of the turbine 22. Downstream of the heat exchanger 62, the compressed and cooled flow of air passes into a water extraction loop 64. This water extraction loop 64 comprises, for example, a reheater made up of an air/air heat exchanger, a condenser likewise made up of an air/air heat exchanger and a water extractor. The cold air expanded at the outlet of the turbine 22 passes through the condenser of the water extraction loop 64 to cool the air flow upstream of the turbine 22, then supplies the mixing chamber 36.

(24) The heat exchanger 62 comprises a second circuit through which the air at dynamic pressure originating from at least one bleed air vent 72 passes to cool the compressed air reheated between the compressor 21 and the turbine 22.

(25) Moreover, a first circuit of an air/air cooling heat exchanger 61 is located between the inlet of the air conditioning system 55 and the air inlet of the compressor 21. The air at dynamic pressure originating from the bleed air vent 72 passes through the second circuit of this heat exchanger 61. This heat exchanger 61 thereby allows the cooling of the air entering the air conditioning pack 55 prior to its input into the compressor 21 of the air cycle turbine engine 20. As indicated previously, according to an embodiment that is not represented, the turbine outlet duct 44 leads into the circulation channel for the air at dynamic pressure originating from the bleed air vent 72.

(26) The circulation of air in the second circuits of the heat exchangers 61, 62 is ensured by the fan 18.

(27) Each heat exchanger 61, 62 allows a transfer of heat between its first circuit and its second circuit depending on the difference of temperature of the air flows respectively passing through each circuit.

(28) An environmental control system according to the embodiment of FIG. 2 thereby allows the supply of air at a temperature and pressure that are controlled by the air conditioning pack 55, while at the same time limiting the bleed on the engine 3 of the aircraft due to the presence of the module 23 for recovery of cabin-energy and its ability to operate in a routine mode in which it provides air at controlled pressure and temperature as a complement to the air provided by the air conditioning pack 55.

(29) Moreover, the invention makes it possible to at least partially compensate for a possible failure of the air conditioning pack by providing an emergency mode in which the control unit 25 of the module 23 controls the opening of the emergency valve 53 to supply the turbine 32 in such a manner as to drive the compressor 31 of the turbine engine 30, allowing air to be supplied at controlled temperature and pressure to the mixing chamber 36.

(30) An aircraft according to the invention can comprise one single engine 3 and one single environmental control system according to the invention. As a variant, the aircraft comprises two propulsion engines and a plurality of environmental control systems according to the invention, or one single environmental control system for a plurality of engines. Likewise, the aircraft can comprise one single cabin-module for recovery of energy for one or more environmental control systems or one module for recovery of energy per environmental control system according to the invention.