초록 ▼

Aircraft environmental control systems having a single ram air inlet providing air to both cabin air compressors and associated heat exchangers are disclosed herein. In one embodiment, and environmental control system for use with an aircraft includes a ram air inlet, an air conditioning pack, and a

Aircraft environmental control systems having a single ram air inlet providing air to both cabin air compressors and associated heat exchangers are disclosed herein. In one embodiment, and environmental control system for use with an aircraft includes a ram air inlet, an air conditioning pack, and an associated heat exchanger. In this embodiment, the ram air inlet provides a first portion of air to the air conditioning pack, and a second portion of air to the associated heat exchanger. The first portion of air flows from the air conditioning pack and through the heat exchanger before flowing into an aircraft cabin. The second portion of air from the ram air inlet cools the first portion of air in the heat exchanger before exiting the aircraft through a ram air outlet. The inlet and outlet can be modulated on an optimized schedule to minimize the net drag of the ram system.

대표청구항 ▼

I claim: 1. An environmental control system (ECS) for use with an aircraft, the ECS comprising: a ram air inlet door operably coupled to a ram air inlet proximate a fuselage of the aircraft; an air conditioning pack that receives a first portion of air from the ram air inlet; a heat exchanger that

I claim: 1. An environmental control system (ECS) for use with an aircraft, the ECS comprising: a ram air inlet door operably coupled to a ram air inlet proximate a fuselage of the aircraft; an air conditioning pack that receives a first portion of air from the ram air inlet; a heat exchanger that receives a second portion of air from the ram air inlet, wherein the first portion of air from the ram air inlet flows from the air conditioning pack and through the heat exchanger before flowing into a cabin of the aircraft, and wherein the second portion of air from the ram air inlet cools the first portion of air in the heat exchanger; a ram air outlet door operably coupled to a ram air outlet that exhausts the second portion of air away from the aircraft after the second portion of air passes through the heat exchanger; and means for automatically controlling the ram air inlet door and the ram air outlet door during operation of the ECS to control ram air flow, to increase air pressure recovery downstream from the ram air inlet door, and to reduce aerodynamic drag caused by the ECS, wherein the means for automatically controlling the ram air inlet door and the ram air outlet door include: means for automatically selecting a position of the ram air inlet door based on a ram air inlet mass flow requirement; and means for automatically selecting a position of the ram air outlet door based on the selected position of the ram air inlet door to thereby increase air pressure recovery downstream from the ram air inlet door and reduce aerodynamic drag. 2. The ECS of claim 1 wherein the ram air inlet is a flush inlet. 3. The ECS of claim 1, further comprising: an inlet duct in flow communication with the ram air inlet; an air passage in flow communication with the inlet duct; and a cabin air compressor operably coupled to the air passage, wherein the first portion of air from the ram air inlet flows through the air passage to the cabin air compressor before flowing through the air conditioning pack, wherein the air conditioning pack includes at least one of an air cycle device and a vapor cycle device, and wherein the first portion of air flows through the air conditioning pack before flowing through the heat exchanger. 4. The ECS of claim 1, further comprising: an inlet duct in flow communication with the ram air inlet and the ram air outlet; an air passage in flow communication with the inlet duct; a cabin air compressor operably coupled to the air passage, wherein the first portion of air from the ram air inlet flows through the air passage to the cabin air compressor before flowing through the air conditioning pack and the heat exchanger, wherein the air conditioning pack includes at least one of an air cycle device and a vapor cycle device, and wherein the second portion of air flows out the ram air outlet after flowing through the heat exchanger. 5. The ECS of claim 1, further comprising: an inlet duct in flow communication with the ram air inlet and the ram air outlet; a cabin air compressor, wherein the first portion of air from the ram air inlet flows through the cabin air compressor before flowing through the air conditioning pack, wherein the air conditioning pack includes at least one of an air cycle device and a vapor cycle device, wherein the first portion of air flows through the air conditioning pack before flowing through the heat exchanger, and wherein the second portion of air flows out the ram air outlet after flowing through the heat exchanger; and wherein the means for automatically controlling modulates the ram air inlet door and the ram air outlet door during operation of the ECS to increase pressure recovery in the inlet duct and reduce aerodynamic drag caused by the ECS. 6. The ECS of claim 1 wherein the means for automatically selecting a position of the ram air outlet door include means for automatically selecting a position of the ram air outlet door based on empirical data illustrating the relationship between the ram air outlet door and the ram air inlet door that yields optimum, or near-optimum, pressure recovery factor and net system drag. 7. An environmental control system (ECS) for use with an aircraft, the ECS comprising: a ram air inlet, wherein the ram air inlet includes: an inlet lip portion; and an inlet door movably positioned at least approximately adjacent to the inlet lip portion to form a variable inlet opening therebetween, the inlet door including: a first surface portion movably positioned upstream of the inlet lip portion, wherein the first surface portion includes a forward edge region spaced apart from the inlet lip portion by a first distance; and a second surface portion fixed at an angle relative to the first surface portion and movably positioned downstream of the inlet lip portion, wherein the second surface portion includes an aft edge region spaced apart from the forward edge region by a second distance that is greater than the first distance, and wherein movement of the inlet door in a first direction reduces the inlet opening to decrease a flow of ram air through the inlet opening, and wherein movement of the inlet door in a second direction enlarges the inlet opening to increase the flow of ram air through the inlet opening; an air conditioning pack that receives a first portion of air from the ram air inlet; and a heat exchanger that receives a second portion of air from the ram air inlet, wherein the first portion of air from the ram air inlet flows from the air conditioning pack and through the heat exchanger before flowing into a cabin of the aircraft, and wherein the second portion of air from the ram air inlet cools the first portion of air in the heat exchanger. 8. The ECS of claim 7, further comprising a ram air outlet that exhausts the second portion of air away from the aircraft after the second portion of air passes through the heat exchanger, wherein the ram air outlet includes a variable outlet opening. 9. An aircraft comprising: a cabin; and an environmental control system (ECS) that provides air to the cabin, the ECS comprising: a ram air inlet having a variable inlet opening in flow communication with an inlet duct; a ram air outlet having a variable outlet opening in flow communication with an exhaust duct; an air conditioning pack that receives a first portion of air from the inlet duct, the air conditioning pack including at least one of an air cycle machine and a vapor cycle machine; a heat exchanger that receives a second portion of air from the inlet duct, wherein the first portion of air flows from the air conditioning pack and through the heat exchanger before flowing into the cabin, and wherein the second portion of air flows through the heat exchanger to cool the first portion of air before flowing out the ram air outlet via the exhaust duct; and means for automatically selecting positions of the variable inlet opening and the variable outlet opening during operation of the aircraft based on a ram air inlet mass flow requirement and based on data indicating desired positions of the variable inlet opening and the variable outlet opening to increase air pressure recovery in the inlet duct and reduce aerodynamic drag caused by the ECS. 10. The aircraft of claim 9 wherein the cabin is a passenger cabin located in a fuselage of the aircraft. 11. The aircraft of claim 9 wherein the means for automatically selecting modulates at least one of the variable inlet opening and the variable outlet opening during operation of the aircraft to increase pressure recovery in the inlet duct. 12. The aircraft of claim 9 wherein the ECS further comprises: an air passage in flow communication with the inlet duct; and a cabin air compressor operably coupled to the air passage, wherein the first portion of air from the ram air inlet flows through the air passage to the cabin air compressor before flowing through the air conditioning pack and the heat exchanger. 13. The aircraft of claim 9 wherein the ECS further comprises: an air passage in flow communication with the inlet duct; and a cabin air compressor operably coupled to the air passage, wherein the air conditioning pack is positioned downstream from the cabin air compressor so that the first portion of air from the ram air inlet flows through the air passage to the cabin air compressor before flowing to the air conditioning pack, and wherein the heat exchanger is positioned downstream from the air conditioning pack so that the first portion of air flows through the air conditioning pack before flowing to the heat exchanger. 14. The aircraft of claim 9 wherein the means for automatically selecting include: means for automatically selecting a position of the variable inlet opening based on test data illustrating the relationship between inlet opening position and ram air mass flow; and means for automatically selecting a position of the variable outlet opening based on test data illustrating the relationship between outlet opening position and inlet opening position. 15. A system for providing outside air to a cabin of an aircraft, the system comprising: means for receiving a flow of outside air while the aircraft is in flight, wherein the means for receiving a flow of outside air include a variable inlet opening; means for dividing the flow of outside air into a first air flow portion and a second air flow portion; means for cooling the first air flow portion with the second air portion before providing the first air flow portion to a cabin of the aircraft; means for exhausting the second air flow portion away from the aircraft after the second air flow portion has cooled the first air portion, wherein the means for exhausting the second air flow portion away from the aircraft include a variable outlet opening; and means for automatically modulating at least one of the variable inlet opening and the variable outlet opening while the aircraft is in flight to reduce loss of air pressure downstream from the variable inlet opening while simultaneously reducing aerodynamic drag, wherein the means for automatically modulating include: means for automatically selecting a position of the variable inlet opening based on a ram air inlet mass flow requirement; and means for automatically selecting a position of the variable outlet opening based on the selected position of the variable inlet opening. 16. The system of claim 15, further comprising means for compressing the first air flow portion before cooling the first air flow portion with the second air flow portion. 17. A method for providing air to an aircraft cabin during flight, the method comprising: receiving a flow of outside air via an air inlet; separating the flow of outside air into a first air flow portion and a second air flow portion; compressing the first air flow portion; after compressing the first air flow portion, cooling the first air flow portion with the second air flow portion; after cooling the first air flow portion with the second air flow portion, directing the first air flow portion into the aircraft cabin and exhausting the second air flow portion via an air outlet; and automatically modulating the air inlet and the air outlet during flight of the aircraft to achieve a desired temperature of the first air flow portion flowing into the aircraft cabin while optimizing pressure recovery and reducing aerodynamic drag, wherein automatically modulating the air inlet and the air outlet during flight comprises selecting a ram air inlet mass flow requirement based on the desired temperature of the first air flow portion flowing into the aircraft cabin; selecting a position of the air inlet based on the selected ram air inlet mass flow requirement; and selecting a position of the air outlet based on the selected position of the air inlet. 18. The method of claim 17, further comprising: after compressing the first air flow portion, and before cooling the first air flow portion with the second air flow portion, directing the first air flow portion through an air conditioning pack. 19. The method of claim 17 wherein exhausting the second air flow portion from the aircraft via an outlet includes wherein exhausting the second air flow portion from the aircraft via an outlet having a variable outlet opening. 20. The method of claim 17 wherein receiving a flow of outside air via an air inlet includes receiving a flow of outside air via a ram air inlet. 21. The method of claim 17 wherein receiving a flow of outside air via an air inlet includes receiving a flow of outside air via a flush inlet having a variable inlet opening. 22. The method of claim 17 wherein compressing the first air flow portion includes directing the first air flow portion through an air compressor, wherein cooling the first air flow portion with the second air flow portion includes directing the first air flow portion through a heat exchanger, and wherein the method further comprises directing the first air flow portion through an air conditioning pack after the first air flow portion flows through the air compressor and before the first air flow portion flows through the heat exchanger.