CN113955123A

CN113955123A - Aircraft dehumidification system

Info

Publication number: CN113955123A
Application number: CN202111502378.8A
Authority: CN
Inventors: 吕中原; 彭莹; 林石泉
Original assignee: Comac Shanghai Aircraft Design & Research Institute; Commercial Aircraft Corp of China Ltd
Current assignee: Comac Shanghai Aircraft Design & Research Institute; Commercial Aircraft Corp of China Ltd
Priority date: 2021-12-09
Filing date: 2021-12-09
Publication date: 2022-01-21

Abstract

The invention discloses a dehumidification system for an aircraft, comprising: the inlet of the compressor is communicated with a preset area in the aircraft; a skin heat exchanger in communication with the compressor outlet to receive a first inboard airflow from the compressor and configured to receive outboard air, the skin heat exchanger configured to exchange heat between the first inboard airflow and the outboard airflow; a regenerator disposed in communication with the skin heat exchanger to receive a first in-machine airflow from the skin heat exchanger, and configured to receive a second in-machine airflow such that heat is exchanged between the first in-machine airflow and the second in-machine airflow, the first in-machine airflow exiting the regenerator to be used as a dehumidified airflow. According to the comprehensive utilization of the heat of the dehumidification system, the energy-saving effect is realized, and the influence on the aerodynamic resistance of the airplane is small.

Description

Aircraft dehumidification system

Technical Field

The invention relates to the technical field of civil aviation, in particular to a dehumidification system of an airplane.

Background

When the airplane flies at high altitude, the glass fiber cotton adopted by the heat-insulating and sound-insulating layer can easily absorb the free water separated out from the exhaust gas in the passenger cabin. Furthermore, the aircraft skin and the metallic structural elements connected to it are very cold, and condensation or icing can occur in these areas, which leads to an increase in the weight of the aircraft and a reduction in the thermal and acoustic insulation properties of the insulation. At present, civil aircraft fuselage dehumidification measure is for the intermediate layer that designs for closed passage between aircraft skin and the adiabatic sound insulation layer in cabin, utilize hot-air to let in wherein and keep warm and prevent to produce the comdenstion water, and send into the passenger cabin by the blast pipe way that is located the cabin top, as shown in figure 1, wherein aircraft dehumidification system main function is to getting into the closed passage between aircraft skin and the adiabatic sound insulation layer in cabin, the hot-air in spaces such as aircraft cabin dehumidifies the drying, prevent that closed passage's air from producing the comdenstion water, protect the organism structure, avoid the insulating layer moisture absorption to increase weight.

At present, two schemes are used for dehumidifying an airplane, one scheme is a rotating wheel dehumidifying system, and the other scheme is a drying system for dehumidifying by utilizing exhaust gas of a refrigerating assembly and an electronic equipment cabin.

The rotary wheel dehumidification system is shown in fig. 3, and comprises a filter, a processing fan, a regeneration heater, a rotary wheel and the like. The dehumidification system guides air from the cargo compartment triangular area under the action of suction force of the fan, the air is divided into two paths and is filtered by the filter, one path of air passes through the dehumidification rotating wheel, water vapor is adsorbed by porous media in the dehumidification rotating wheel and stays in the dehumidification rotating wheel, the treated air becomes dry air and is distributed to the ceiling at the top of the passenger cabin through the ascending pipe and the flute-shaped pipe, and an air heat insulation layer is formed between interlayers at two sides of the passenger cabin to inhibit the heat insulation and sound insulation layer from absorbing moisture; the other path of air is heated into high-temperature air by a regenerative heater, takes away the water vapor in the porous medium after passing through the dehumidification rotating wheel, and is exhausted to the outside of the machine through an exhaust valve. Under the action of the driving motor, part of the porous medium absorbs moisture continuously and is dried and regenerated. However, in this solution, since the temperature required for porous medium regeneration is 80-150 ℃, the heater consumes a large amount of electricity, resulting in a compensatory loss of power extraction fuel. In addition, if the fuselage adopts combined material, the regeneration gas temperature is higher, can not directly discharge.

In "a drying system for use in an aircraft" (publication No. CN 102179140A) proposed by shanghai institute of aircraft design, grand schoold, a drying (dehumidifying) system for dehumidifying with a refrigeration assembly and with electronic equipment compartment exhaust air is proposed, as shown in fig. 4, the system comprising: a refrigeration assembly, a heat exchanger, and a distribution line. Thereby the humid air carries out dehumidification for the first time after through refrigeration assembly and reduces its absolute humidity, and the air after the dehumidification for the first time enters into heat exchanger, and heat exchanger is used for carrying out the heat exchange with the hot waste gas of electronic equipment cabin exhaust and the cold fresh air of refrigeration assembly exhaust thereby carry out the dehumidification for the second time and obtain dry air with reducing its relative humidity, and dry air carries to the fuselage in-layer through the distribution pipeline. However, in this scheme, since the fresh air is dehumidified by the refrigeration assembly in the first dehumidification, the refrigeration assembly needs to draw high-temperature and high-pressure air of the engine, which brings about engine bleed air and fuel compensation loss.

In a comprehensive view, the two schemes can cause the compensation loss of fuel oil, and the economy is not high; therefore, a new dehumidification system with low power consumption, low energy consumption and high reliability is needed.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a dehumidification system for an aircraft, in particular a civil aircraft, which comprises: the air compressor is provided with an air compressor inlet and an air compressor outlet, and the air compressor inlet is communicated with a preset area in the aircraft; a skin heat exchanger in communication with the compressor outlet to receive a first inboard airflow from the compressor and configured to receive outboard air, the skin heat exchanger configured to exchange heat between the first inboard airflow and the outboard airflow; a regenerator disposed in communication with the skin heat exchanger to receive a first in-plane airflow from the skin heat exchanger, and configured to receive a second in-plane airflow to exchange heat between the first in-plane airflow and the second in-plane airflow, the first in-plane airflow exiting the regenerator being used as a dehumidified airflow.

According to another aspect of the invention, the predetermined area is a cargo compartment triangle of the aircraft.

According to yet another aspect of the present invention, the skin heat exchanger has a first flow path along which the first inner airflow flows and a second flow path along which the outer airflow flows, which perform a heat exchange function with each other; the regenerator comprises a third flow path and a fourth flow path which realize heat exchange between the third flow path and the fourth flow path, the first inner airflow flows along the third flow path, and the second inner airflow flows along the fourth flow path; wherein the inlet of the first flow path is connected to the outlet of the compressor, the outlet of the first flow path is connected to the inlet of the third flow path, and the outlet of the third flow path is communicated with an interlayer between the skin of the airplane and the heat and sound insulation layer.

According to yet another aspect of the invention, the dehumidification system includes an exhaust structure, an inlet of the fourth flow path is communicated to an electronics compartment and/or lavatory, and an outlet of the fourth flow path is connected to the exhaust structure.

According to a further aspect of the invention, the outlet of the fourth flow from the regenerator leads to two branches, one of which leads via an intrabay shutter to an exhaust shutter and the other of which leads directly to an extrabay shutter.

According to yet another aspect of the invention, the second in-line airflow is airflow from the electronics bay and/or lavatory.

According to yet another aspect of the present invention, further comprising a drive means for drawing the second stream of air into the regenerator, the drive means comprising an exhaust fan.

According to a further aspect of the invention, the air conditioner further comprises a filter disposed upstream of the compressor, and the air flow from the predetermined region flows into the compressor after passing through the filter.

According to a further aspect of the invention, a water collection screen is provided in the skin heat exchanger to dehumidify the first in-machine airflow.

The dehumidification system according to the invention brings about a number of advantages compared to existing aircraft dehumidification systems.

Firstly, the dehumidification system has simple structure and high reliability. Only one air compressor and one skin heat exchanger are needed to be added, a good dehumidification effect can be achieved, and the dehumidification requirement of the airplane can be met in the whole flight envelope.

Secondly, the dehumidification system realizes comprehensive utilization of heat, and the dehumidification process fully utilizes waste heat in exhaust air of the electronic equipment cabin and the washroom. The air from the cargo compartment triangular area firstly transfers the heat of the air to the outside air in the dehumidification heat exchanger, and then absorbs the waste heat in the electronic equipment compartment and the washroom in the heat regenerator, thereby realizing the effect of energy conservation.

Thirdly, the dehumidification system according to the invention has a small impact on the aerodynamic drag of the aircraft. The heat exchange with the outside air is realized through the skin heat exchanger, no additional opening is needed on the machine body, and the influence brought by the aerodynamic resistance is reduced.

Drawings

For a more complete understanding of the present invention, reference is made to the following description of exemplary embodiments taken in conjunction with the accompanying drawings, in which:

fig. 1 shows a cross-sectional view of an aircraft cabin to which a dehumidification system according to the invention is applied.

FIG. 2 shows a schematic diagram of a dehumidification system in accordance with a preferred embodiment of the present invention.

Fig. 3 shows a schematic diagram of a dehumidification system in the prior art.

Fig. 4 shows a schematic view of another dehumidification system in the prior art.

List of reference numerals

10 dehumidification system

11 Filter

12 air compressor

15 covering heat exchanger

151 filter screen

16 heat regenerator

17 electronic equipment compartment

18 lavatory

19 exhaust fan

20 inner valve

21 outer valve

22 exhaust valve

23 fuselage skin

Detailed Description

The present invention is further described in the following description with reference to specific embodiments and the accompanying drawings, wherein the details are set forth in order to provide a thorough understanding of the present invention, but it is apparent that the present invention can be embodied in many other forms different from those described herein, and it will be readily appreciated by those skilled in the art that the present invention can be implemented in many different forms without departing from the spirit and scope of the invention.

Fig. 1 shows a cross-sectional view of an aircraft cabin. The passenger cabin and the cargo compartment are respectively positioned above and below the fuselage, and two sides of the lower cargo compartment are cargo compartment triangular areas. The outermost layer of the cabin is a skin, and the inner part of the cabin is a heat and sound insulation layer, and an interlayer is formed between the skin and the heat and sound insulation layer. As can be seen from figure 1, a heat-insulating and sound-insulating layer is laid on one side of the cargo compartment triangular area, which is close to the skin. The aircraft dehumidification system 10 according to the preferred embodiment provides for the passage of hot air into the interlayer for insulation against the formation of condensation.

Fig. 2 illustrates a novel aircraft dehumidification system 10 in accordance with a preferred embodiment of the present invention. The aircraft dehumidification system 10 generally comprises: a compressor 12, a skin heat exchanger 15 and a regenerator 16.

The compressor 12 may be an axial-flow electric compressor and is arranged primarily to feed the aircraft interior air (i.e., the first stream) of a predetermined region of the aircraft interior to the skin heat exchanger 15. Specifically, the compressor 12 has a compressor inlet and a compressor outlet, with the compressor inlet being connected to a predetermined region of the aircraft interior by a conduit. According to a preferred embodiment of the invention, the predetermined area is in particular a cargo compartment triangular area, as shown in fig. 1. The cargo compartment delta is in fluid communication with the passenger cabin, and air within the passenger cabin can be vented outside the cabin through the cargo compartment delta. Because the cargo compartment triangular area is also provided with the heat and sound insulation layer, the air temperature of the cargo compartment triangular area is close to the air temperature in the passenger compartment.

Further, in the dehumidification system 10 according to the preferred embodiment of the present invention, the compressor outlet communicates with the skin heat exchanger to receive the inboard air flow delivered by the compressor 12.

The skin heat exchanger 15 acts as a heat sink with the cold air outside the aircraft in order to reduce the absolute humidity of the air in the aircraft from the cargo compartment triangle. As a rule, the air temperature in the region of the cargo compartment triangle on the side close to the skin is relatively close to the air temperature in the passenger compartment, whereas the air temperature outside the aircraft is much lower, as a result of which an effective heat exchange between the two air streams is possible.

The skin heat exchanger 15 has a first flow path and a second flow path for heat exchange with each other, and a first inboard air flow from the cargo compartment triangle flows along the first flow path, and an outboard air flow flows along the second flow path, so that when two air flows of the first inboard air from the cargo compartment triangle and the aircraft outside air flow through the skin heat exchanger 15, heat transfer occurs between the two air flows, which lowers the temperature of the first inboard air flow and lowers the humidity of the air in the air flow.

Specifically, the hot edge of the skin heat exchanger 15 may adopt a plate-fin type, and the external air cools the air at the outlet of the compressor through the outer skin of the skin heat exchanger 15; condensed water is separated out from the air cooled by the skin heat exchanger 15, and after the condensed water and the air pass through the water collection filter screen 151 along with the air flow, the condensed water forms low-temperature dry air after passing through the water collection filter screen 151, so that the absolute humidity is reduced, and primary dehumidification is formed.

Further, in the dehumidification system 10 according to the preferred embodiment of the present invention, downstream of the first in-machine airflow, the regenerator 16 is disposed in communication with the skin heat exchanger 15 to receive the first in-machine airflow from the skin heat exchanger 15, and the regenerator 16 is configured to receive another relatively higher temperature in-machine airflow (i.e., a second in-machine airflow) such that the two in-machine airflows exchange heat within the regenerator 16.

Specifically, the regenerator 16 includes two flow paths, hereinafter referred to as a third flow path and a fourth flow path, which have a heat exchange function with each other, a first internal airflow flows out of the skin heat exchanger 15 and then enters the regenerator 16 to flow along the third flow path, and a second internal airflow with a relatively high temperature flows along the fourth flow path, so that the first internal airflow is heated by the regenerator 16 and then becomes dry air with a relatively high temperature. The dry air is then fed into the interlayer between the fuselage skin 23 on the outside of the aircraft cabin and the insulating and sound-insulating layer on the inside, forming a dehumidification circuit.

In particular, another inboard air flow of relatively high temperature may be exhausted from the electronics compartment 17 and/or the lavatory 18.

Preferably, as can be seen in fig. 2, upstream of the compressor 12, the dehumidification system 10 is also provided with a filter 11, the outlet of which filter 11 is connected to the inlet of the compressor 12. The filter 11 filters air from the cargo compartment triangle to improve airflow cleanliness and also protect subsequent equipment.

The dehumidification system 10 according to the present invention arranges the skin heat exchanger 15 and the regenerator 16 in series, the warmer and more humid air from the cargo compartment delta constituting the first in-plane air flow, the air flow flows through the skin heat exchanger 15 under the driving action of the compressor 12, the cold side fluid of the skin heat exchanger 15 is ram air with lower external temperature, the first in-machine air with higher humidity flows through the skin heat exchanger 15 and is cooled to reduce the temperature, since the moisture-containing capacity of the humid air decreases with decreasing temperature, as the temperature of the first inboard air flow decreases by virtue of the low temperature of the outboard air flow, when the first indoor unit airflow reaches the dew point temperature, water vapor in the air begins to condense to generate precipitation moisture, the water vapor in the air condenses into water drops, the water drops are collected by the water collection filter screen 151 and then are discharged out of the machine, the absolute humidity is reduced, and therefore the first indoor unit airflow achieves primary dehumidification in the skin heat exchanger 15. The low-temperature air after primary dehumidification continues to flow through the heat regenerator 16, the temperature rises, and the relative humidity is further reduced compared with the relative humidity before dehumidification, so that secondary dehumidification of the first internal air flow is realized by means of the heat regenerator 16.

Furthermore, as shown in fig. 2, the dehumidification system 10 further comprises a driving device for drawing the second flow of air into the regenerator 16, preferably an exhaust fan 19, whereby the exhaust fan 19 can be used to draw air from the electronics bay 17 and/or the washroom 18.

The dehumidification system 10 also includes an exhaust structure for a second in-machine airflow downstream of the exhaust fan 19. Preferably, the exhaust structure mainly includes two branches, wherein one branch is arranged to guide the second internal airflow at the outlet of the exhaust fan 19 to the internal valve 20, and further to the vicinity of the exhaust valve 22, and then to be exhausted outside through the exhaust valve 22; the other branch is arranged to discharge the second inside air stream flowing out of the exhaust fan 19 directly out of the machine through the machine-exterior shutter 21.

When the airplane is on the ground, the internal valve 20 is closed, the external valve 21 is opened, and the air in the electronic equipment cabin 17 is exhausted out of the airplane through the external valve 21; in case of high-altitude flight, the outer flap 21 is closed, the inner flap 20 is opened, and the second inner airflow from the regenerator 16 is sent to the vicinity of the exhaust flap 22 and is exhausted out of the aircraft through the exhaust flap 22 under the action of the difference between the pressure inside and outside the aircraft.

With the dehumidification system 10 according to the present invention, when the aircraft flies at low altitude or on a hot ground, the outside air temperature is high, the humidity is high, no condensed water is generated in the skin heat exchanger 15 of the dehumidification system 10, and then the air is heated in the heat regenerator 16, the temperature is raised, the relative humidity is reduced, and the purpose of preventing moisture precipitation is achieved. When the aircraft flies from high altitude to low altitude or flies to the ground, the skin temperature is still lower, the outside air temperature is higher, the humidity is higher, and when the air heated by the heat regenerator 16 passes through the aircraft structure interlayer, condensed water can not be generated, thereby playing the effect of protecting the heat insulation and sound insulation layer on the inner side of the skin.

The technical scheme of the invention solves the problems of poor economical efficiency, high heating temperature and incapability of directly discharging hot gas in the existing scheme, and provides a novel dehumidification system 10 for dehumidifying by utilizing the outside air of an airplane and the waste heat of the waste gas in an electronic equipment cabin 17 and a washroom 18.

The invention utilizes the air outside the machine as the cold source to cool and dehumidify the air in the cargo compartment triangular area during primary dehumidification, compared with the prior art shown in figure 4, the invention does not need a refrigeration assembly to cool, and simultaneously does not need the air bleed of the engine, thereby reducing the fuel compensation loss caused by the air bleed of the engine.

Compared with the prior art shown in figure 4, the dehumidification system of the invention adopts the skin heat exchanger 15, does not need a ram air duct, does not need an opening on the skin of the machine body, and reduces the fuel compensation loss caused by ram air.

In addition, the scheme adopts the exhaust waste heat of the electronic equipment cabin 17 and the washroom 18 for secondary dehumidification, and compared with the prior art shown in fig. 3, the scheme does not need power consumption, and solves the problem of poor economical efficiency in the prior art. In the invention, the exhaust waste heat of the electronic equipment cabin and the washroom 18 is adopted for secondary dehumidification, compared with the prior art shown in figure 3, the exhaust temperature is low, and the problem that hot air cannot be directly discharged is solved.

Although the present invention has been disclosed in terms of the preferred embodiment, it is not intended to limit the invention, and variations and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention. Therefore, any modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope defined by the claims of the present invention, unless the technical essence of the present invention departs from the content of the present invention.

Claims

1. A dehumidification system for an aircraft, comprising:

the air compressor is provided with an air compressor inlet and an air compressor outlet, and the air compressor inlet is communicated with a preset area in the aircraft;

a skin heat exchanger in communication with the compressor outlet to receive a first inboard airflow from the compressor and configured to receive an outboard airflow, the skin heat exchanger configured to exchange heat between the first inboard airflow and the outboard airflow;

a regenerator disposed in communication with the skin heat exchanger to receive a first in-machine airflow from the skin heat exchanger, and configured to receive a second in-machine airflow for heat exchange between the first in-machine airflow and the second in-machine airflow within the regenerator, the first in-machine airflow exiting the regenerator being used as a dehumidified airflow.

2. A dehumidification system for an aircraft according to claim 1, wherein said predetermined area is a cargo compartment trigon of the aircraft.

3. A dehumidification system for an aircraft according to claim 1, wherein said skin heat exchanger has a first flow path and a second flow path for exchanging heat with one another, said first inner airflow flowing along said first flow path and said outer airflow flowing along said second flow path;

the regenerator comprises a third flow path and a fourth flow path which realize heat exchange between the third flow path and the fourth flow path, the first inner airflow flows along the third flow path, and the second inner airflow flows along the fourth flow path;

wherein the inlet of the first flow path is connected to the outlet of the compressor, the outlet of the first flow path is connected to the inlet of the third flow path, and the outlet of the third flow path is communicated with an interlayer between the skin of the airplane and the heat and sound insulation layer.

4. A dehumidification system for an aircraft according to claim 3, wherein the dehumidification system comprises an exhaust structure,

an inlet of the fourth flow path is communicated to an electronics bay and/or lavatory and an outlet of the fourth flow path is connected to the exhaust structure.

5. A dehumidification system for an aircraft according to claim 3, wherein an outlet of said fourth flow from said regenerator leads to two branches, one of said two branches leading to an exhaust flap via an inboard flap and the other of said two branches leading directly to an outboard flap.

6. Dehumidification system for an aircraft according to any one of claims 1 to 3,

the second in-line airflow is airflow from an electronics bay and/or a lavatory.

7. The dehumidification system for an aircraft according to claim 1, further comprising a drive for drawing the second in-plane airflow into the thermal regenerator, the drive comprising an exhaust fan.

8. The dehumidification system for an aircraft as defined in claim 1, further comprising a filter disposed upstream of the compressor, wherein the air flow from the predetermined region flows into the compressor after passing through the filter.

9. A dehumidification system for an aircraft according to claim 1, wherein a collection screen is provided in the skin heat exchanger to dehumidify the first in-aircraft airflow.