JP2005014745A - Air conditioner for aircraft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce consumption of engine fuel required for air-conditioning at a high altitude. <P>SOLUTION: This device is provided with an exhaust using air-conditioning system A having an air cycle machine 12 comprising a compressor 12a for compressing the outside air or fan bleeding 11A of a turbo fan engine and supplying the compressed air into the aircraft and an exhaust turbine 12b using exhaust air 11C to the outside as a power source, and an air cycle air-conditioning system B using bleeding 1A from an APU or an engine compressor as operation energy. Only at the high altitude cruising, the exhaust using air-conditioning system A is operated, and the bleeding 11A is dispensed with, and thereby the fuel consumption can be reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an aircraft air conditioner that controls the in-flight temperature and pressure of an aircraft.
[0002]
[Prior art]
Conventionally, an air cycle system has been generally used for an air conditioner for aircraft. This is because, in addition to temperature control, the condition that pressurization is required in the aircraft at a high altitude, that high-pressure engine bleed air can be used, and that it is compact and lightweight is satisfied. In recent years, a system that is generally used is a system called a 3-wheel, HPWS (High Pressure Water Separation) system as shown in FIG. 4 (see, for example, Patent Document 1).
[0003]
In this HPWS air conditioning system, extraction air 1A, which is high-temperature and high-pressure air from an engine compressor or APU (auxiliary power unit), is cooled by ram air 1B in a primary heat exchanger 2, and a compressor 31, an extraction turbine 32, and a fan 33 are cooled. After being compressed by the compressor 31 of the air cycle machine (ACM) 3 consisting of the following, cooled by the ram air 1B again by the secondary heat exchanger 4, and then dehumidified by the dehumidifying mechanism 5 consisting of the reheater 51, the condenser 52 and the water extractor 53, A low temperature air 1C is obtained by adiabatic expansion by the extraction turbine 32 of the air cycle machine 3. The power of the extraction turbine 32 is used to drive the compressor 31 and the extraction air 1A or the fan 33 for drawing in the ram air 1B during low-speed flight. The low-temperature air 1 </ b> C is mixed with circulating air 1 </ b> D circulated from the in-machine pressurizing chamber 7 in the mixing chamber 6, pressurized at an appropriate temperature, and supplied to the in-machine pressurized chamber 7.
[0004]
These air-cycle air-conditioning systems generally use the same auxiliary air-conditioning system C as a spare per switching valve 8 so that constant air conditioning can be performed even if one of the air-conditioning systems breaks down during flight. Can be switched. Further, in order to keep the pressure in the in-machine pressurizing chamber 7 constant, an in-machine pressurization control system called CPCS (Cabin pressure Control System) is in operation, and the outflow valve 7 is controlled from the outflow valve 7 for pressurization control. Exhaust air 1E is discharged.
[0005]
[Patent Document 1]
JP 2002-96799 A [0006]
[Problems to be solved by the invention]
A conventional air conditioner for an aircraft using an air cycle system is configured as described above. However, an air conditioning system using an air cycle system uses the energy of high-temperature and high-pressure extraction air 1A from an engine / compressor during flight. Since it is driven, it is necessary to extract high-pressure air directly from the engine. This not only requires the engine side to create extra high-pressure air, but also reduces the efficiency of the engine itself, which is a heavy burden on the aircraft. For this reason, the air conditioner for aircraft must be capable of efficiently performing in-flight air conditioning at a low pressure and a low flow rate, and needs to contribute to reducing fuel consumption of the aircraft.
The present invention has been made in view of such a situation, and an object of the present invention is to provide an aircraft air conditioner that can achieve a reduction in the burden on the engine (that is, a reduction in fuel consumed by the air conditioner). To do.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an air conditioner for an aircraft according to the present invention takes outside air or fan bleed air of a turbofan engine as fresh air, compresses the fresh air and supplies the fresh air to the inside of the air compressor, and the outside. An exhaust-type air conditioning system equipped with an air cycle machine consisting of an exhaust expansion turbine that uses exhaust air to be exhausted as a power source, and bleed air from the auxiliary power unit or the compressor of the engine is cooled and supplied as fresh air to the in-machine pressurized chamber Air cycle type air-conditioning air conditioning system is installed side by side, and an exhaust-type air conditioning system is operated during high-altitude cruising, and the air-cycle type air-conditioning system is operated during flight on the ground and at low altitudes. Was established.
In addition, when an electric motor is connected to the exhaust expansion turbine and the outside air is compressed, necessary power is obtained by the electric motor together with the power obtained by the exhaust expansion turbine.
The air conditioning apparatus for aircraft according to the present invention is configured as described above, and it is not necessary to extract air from the engine / compressor during flight, and the fuel consumption is greatly reduced by the operation of the exhaust air conditioning system. .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings. In the figure, the same parts as those in the conventional example of FIG. FIG. 1 is a system configuration diagram showing the configuration of an aircraft air conditioner according to the present embodiment. As shown in FIG. 1, the air conditioning apparatus for an aircraft basically controls, for example, the temperature and pressure of an in-machine pressurizing chamber R that requires pressurization such as a cabin or a cockpit. In order to keep the chamber R at a constant temperature and a constant atmospheric pressure, mixing air is supplied to the in-machine pressurizing chamber R by mixing low-temperature air obtained by air conditioning with the circulating air 1D from the in-machine pressurized chamber R. 6 and an air-conditioning air conditioning system A that uses the mixing chamber 6 for air conditioning during high altitude cruising and an air cycle air conditioning system B that performs air conditioning during ground and low altitude flight. ing.
[0009]
The in-machine pressurizing chamber R has an exhaust line 16 for sending exhaust air 11C while the exhaust air-conditioning air conditioning system A is in operation, and an outflow valve 7 for discharging the exhaust air 11C outside the equipment while the air cycle air-conditioning system B is in operation. The control valve 10a is provided for the intake air 11A from the outside air or the engine fan, the control valve 10b is provided for the air extraction 1A from the APU or the engine compressor, and the exhaust air-conditioning system A, air cycle type Switching valves 8 are provided for switching the flow path of the supply air from the air conditioning system B, respectively.
[0010]
The exhaust-use air conditioning system A is a system that performs air conditioning when flying at a high altitude that is higher than a preset altitude (usually setting the cruise altitude). The air pressure at 2400 m (570 mmHg) is maintained, and the compressor 12a for compressing the outside air or the bleed air 11A from the engine fan, the pressure difference between the in-machine pressurized chamber R and the outside of the machine (for example, 6,000 to When navigating at an altitude of 13,700 m, an exhaust turbine 12b that expands exhaust air 11C discharged to the outside as an inlet air using a maximum of 460 mmHg), and further adds power if necessary Supply pressure / flow rate of supply air 11E supplied to the in-machine pressurizing chamber R, with an air cycle machine 12 including an electric motor 12c as a main component. A control valve 13 for adjusting, a heat exchanger 14 for adjusting the temperature of the outlet air of the compressor 12a compressed to a pressure that can be supplied to the in-machine pressurizing chamber R, and supply air 11E is supplied to the in-machine pressurizing chamber R Supply line 15, an exhaust line 16 for guiding the exhaust air 11C to the exhaust turbine 12b, a control valve 17 for controlling the flow rate, and the like.
[0011]
In the exhaust-use air conditioning system A configured as described above, the exhaust air 11C exhausted from the in-machine pressurizing chamber R is guided to the exhaust turbine 12b via the control valve 17 that controls the in-machine pressure and the exhaust air flow rate, and is insulated. After expansion, it is exhausted out of the machine. As a result, power is generated in the exhaust turbine 12b, and the obtained power is used to drive the compressor 12a coupled to the exhaust turbine 12b with a short shaft. If the exhaust turbine 12b alone cannot supply sufficient power, the electric motor 12c is further connected to assist the drive of the compressor 12a with the power. The compressor 12a obtains the above power and compresses the outside air or the extracted air 11A from the engine fan to a pressure sufficient to supply the inside of the apparatus. The compressed supply air 11E is adjusted to an appropriate temperature by heat exchange with the ram air 11B in the heat exchanger 14, and then the pressure and pressure at the outlet of the compressor 12a are controlled by a control valve 13 that controls the supply pressure and flow rate in the apparatus. The flow rate is adjusted and supplied to the in-machine pressurizing chamber R.
[0012]
The air-cycle type air conditioning system B is the same as the conventional air conditioning system shown in FIG. 4, and compresses the extracted air 1A from the APU or the engine compressor as shown in FIG. After the air is dehumidified by the dehumidifying mechanism 5 including the reheater 51, the condenser 52, and the water extractor 53, an air conditioning system having an air cycle machine 3 that is introduced into the extraction turbine 32 and operates the compressor 31 with the generated power is used. .
[0013]
FIG. 3 shows a control device 20 for controlling the operation of the exhaust air conditioning system A and the air cycle air conditioning system B, and a control valve 10a, a control valve 10b, a switching valve 8, an altimeter 21 and an atmospheric pressure in the aircraft air conditioner. When the aircraft flies on the ground or in a low altitude by the control device 20, the altitude meter 21 and the preset altitude are compared, the control valve 10a is closed, and the control valve 10b is closed. The opening and switching valve 8 is switched to the air cycle type air conditioning system B side as shown in FIG. As a result, the bleed air 1A from the APU or the engine compressor is introduced into the compressor 31 of the air cycle air conditioning system B. The compressed air extracted from the extraction turbine 32 is dehumidified, and then supplied to the in-machine pressurizing chamber R through the switching valve 8 and mixed with the air in the in-machine pressurization chamber R through the mixing chamber 6. Then, the signal of the barometer 22 in the in-machine pressurizing chamber R and the atmospheric pressure set value are compared, and the outflow valve 7 is controlled so as to reach a predetermined atmospheric pressure.
[0014]
Next, when the aircraft is flying at a high altitude (cruising altitude or higher), the control valve 10a is opened, the control valve 10b is closed, and the switching valve 8 is switched to the exhaust-use air conditioning system A as shown in FIG. As a result, the air 11A extracted from the outside air or the engine fan is introduced into the compressor 12a. The air compressed by the compressor 12a is cooled by the ram air 11B, and the low temperature air is mixed with the air in the in-machine pressurizing chamber R in the mixing chamber 6 and supplied to the in-machine pressurized chamber R. The atmospheric pressure in the in-machine pressurizing chamber R is controlled by the control valve 17.
[0015]
The exhaust-use air conditioning system A operates only at high altitudes, but since the humidity in the atmosphere is extremely low at high altitudes, the dehumidifying mechanism 5 used in the air cycle air conditioning system B is unnecessary. In addition, even if it breaks down, it is possible to cover the minimum air conditioning like the conventional system by operating another air cycle type air conditioning system B.
[0016]
The air conditioner for aircraft of the present invention includes an exhaust-type air conditioning system A that uses outside air or extraction from an engine fan as an air-conditioning air source, and an air-cycle type air conditioning system B that uses extraction from an APU or engine compressor. It is characterized in that it is used by switching according to the operating altitude, and is not limited to the embodiment. For example, as an air cycle type air conditioning system B, an exhaust turbine is connected to the extraction turbine output shaft for efficiency. It is also possible to use a material with an increased height.
[0017]
【The invention's effect】
The air conditioner for aircraft according to the present invention is provided with an exhaust turbine in an air conditioning system during high-altitude cruising, uses fresh air or bleed air from an engine fan as a fresh air source, and uses electric power when necessary. By driving the air cycle machine, it is possible to completely eliminate the bleed from the engine / compressor during the high altitude cruising time with the highest fuel consumption, and the fuel consumption of the aircraft can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a system configuration diagram showing the configuration of an embodiment of the present invention.
FIG. 2 is a system configuration diagram showing a configuration of an air cycle type air conditioning system according to the embodiment.
FIG. 3 is a block diagram illustrating a control unit and its control end according to the embodiment.
FIG. 4 is a system configuration diagram of a conventional aircraft air conditioner.
[Explanation of symbols]
1A Extraction 1D Circulating air 6 Mixing chamber 7 Outflow valve 8 Switching valve 10a Control valve 10b Control valve 11A Extraction 11B Ram air 11C Exhaust air 11E Supply air 12 Air cycle machine 12a Compressor 12b Exhaust turbine 12c Electric motor 13 Control valve 14 Heat exchanger 15 Supply line 16 Exhaust line 17 Control valve A Exhaust air-conditioning system B Air-cycle air conditioning system R In-machine pressurized chamber

Claims (2)

An air cycle machine comprising a compressor that takes outside air or fan bleed air of a turbofan engine as fresh air, compresses the fresh air into the machine, and exhaust exhaust turbine that uses exhaust air exhausted outside the machine as a power source Equipped with an exhaust-type air-conditioning system and an air-cycle air-cycle air-conditioning system that cools the bleed air from the auxiliary power unit or the compressor of the engine and supplies it as fresh air into the in-machine pressurized chamber. An air conditioning apparatus for an aircraft, comprising a switching mechanism for switching an air-conditioning system to operate so that an exhaust-type air conditioning system is operated during cruising, and to operate the air-cycle type air conditioning system during ground and low-altitude flight. When the electric motor is connected to the exhaust expansion turbine and the outside air is compressed, an air cycle machine is provided that can obtain necessary power by the electric motor together with power obtained by the exhaust expansion turbine. Item 2. An air conditioner for aircraft according to Item 1.

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