Aircraft heat exchange system based on bidirectional injection

Abstract

The application belongs to the field of aviation environmental control system design, and particularly relates to a bidirectional-ejection-based aircraft heat exchange system. The system comprises a ram air inlet channel, a heat exchanger and an air circulator. The ram air inlet channel comprises a ram air inlet section (1), a transition ejection section (4) and a ram air outlet section. The heat exchanger comprises an air-liquid heat exchanger (2), a first air-air heat exchanger and a second air-air heat exchanger. The air circulator comprises a first air circulator and a second air circulator. The bidirectional-ejection-based aircraft heat exchange system utilizes the principle of constant entropy ejection to limit the ram air flow entering the left and right ram air outlet channels, and integrates the cold side of the heat exchanger with the ram air inlet channel, and matches the dynamic pressure brought by the ram air with the flow resistance of the heat exchanger group, thereby effectively avoiding problems such as fan overspeed, windmill effect and surge of the air circulator.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of aircraft environmental control system design, and particularly relates to an aircraft heat exchange system based on bidirectional injection. BACKGROUND

[0002] The environmental control system mainly ensures the safety and comfort of the aircraft crew and passengers, and provides normal working environment conditions for on-board electronic equipment. The refrigeration system is a key subsystem of the environmental control system (ECS), and the aircraft mainly adopts an air cycle refrigeration system taking air as the circulating medium, which mainly includes an air cycle machine for cooling high-temperature and high-pressure air, a valve for adjusting temperature and flow, and a heat exchanger for discharging heat outside the aircraft.

[0003] The essence of the working process of the aircraft refrigeration system is energy transfer. The conventional aircraft refrigeration system dissipates the energy carried by the high-temperature and high-pressure gas from the engine to the outside atmosphere through the radiator, so that the supply air temperature is reduced to an appropriate range and supplied to the cabin, and the energy of the air with a higher temperature in the cabin is absorbed, thereby realizing the refrigeration function of the aircraft cabin.

[0004] The refrigeration system of a special aircraft often has strict requirements on performance, volume and weight, and therefore a T-F (turbine-fan type) is often used. With the progress of aviation science and technology, air dynamic pressure bearings have begun to be widely used in air cycle machines, which are highly reliable and maintenance-free, but they have brought new problems such as overspeed of the fan end of the air cycle machine, windmill effect and surge. Specifically, (1) when the mass flow of cold-side ram air of the heat exchanger is too high, an extreme phenomenon will occur: the air flow through the fan exceeds the capacity of the fan load, and the fan speed will increase, which will cause damage to the air cycle machine within a certain time when the fan maintains a high speed. (2) When the mass flow of cold-side ram air is too low, the fan will enter the surge region, that is, the separation zone of the fan will continuously expand, and the vortex zone will appear in most of the passages of the blades, the air flow into the blades will be temporarily interrupted, and the gas may flow from the outlet to the inlet in the separated vortex zone, and at the same time, due to the disappearance of the adverse pressure gradient, the air re-enters the turbine, and re-separation and backflow occur. This phenomenon continues at a low frequency, forming a surge, and the air flow appears violent vibration, causing strong vibration of the blades. This phenomenon will cause the impeller to be subjected to great dynamic stress and strong vibration, and damage will occur in a short time, so the air cycle machine fan is not allowed to work in the surge state. In addition, (3) if the air cycle machine is in a non-working state, the air dynamic pressure bearing is not floating, and since the ram air directly flows into the fan end, the dynamic pressure brought by the ram air will drive the fan to rotate and drive the turbine to rotate, which will cause dry grinding damage to the radial bearing and cause product failure.

[0005] Therefore, it is desirable to have a technical solution to overcome or at least alleviate at least one of the above-mentioned defects of the prior art. SUMMARY

[0006] The purpose of the present application is to provide a two-way ejector-based aircraft heat exchange system to solve at least one problem existing in the prior art.

[0007] The technical solution of the present application is:

[0008] A two-way ejector-based aircraft heat exchange system, comprising:

[0009] A ram intake, comprising a ram inlet section, a transition ejector section, and a ram outlet section;

[0010] A heat exchanger, comprising an air-liquid heat exchanger, a first air-air heat exchanger, and a second air-air heat exchanger;

[0011] An air circulator, comprising a first air circulator and a second air circulator;

[0012] Wherein,

[0013] A first end of the ram inlet section is connected to a ram air duct;

[0014] A cold fluid inlet duct of the air-liquid heat exchanger is connected to a second end of the ram inlet section, a hot fluid inlet duct of the air-liquid heat exchanger is connected to a liquid outlet duct of an electronic device, and a hot fluid outlet duct of the air-liquid heat exchanger is connected to a liquid inlet duct of the electronic device;

[0015] A first end of the transition ejector section is connected to a cold fluid outlet duct of the air-liquid heat exchanger, two baffles are arranged inside the transition ejector section, the two baffles divide the airflow channel inside the transition ejector section into a left airflow channel, a middle airflow channel, and a right airflow channel, and the end portions of the two baffles have a predetermined gap with the end portion of the ram outlet section, thereby forming an ejector gap in the transition ejector section;

[0016] A cold fluid inlet duct of the first air-air heat exchanger is connected to a second end of the transition ejector section and communicates with the left airflow channel, and a hot fluid inlet duct of the first air-air heat exchanger is connected to an engine bleed air duct;

[0017] A cold fluid inlet duct of the second air-air heat exchanger is connected to the second end of the transition ejector section and communicates with the right airflow channel, and a hot fluid inlet duct of the second air-air heat exchanger is connected to the engine bleed air duct;

[0018] The stamping outlet section comprises a left stamping outlet channel, a right stamping outlet channel, and a main exhaust channel, a first end of the left stamping outlet channel is connected with a cold fluid outlet pipeline of the first air-to-air heat exchanger, a first end of the right stamping outlet channel is connected with a cold fluid outlet pipeline of the second air-to-air heat exchanger, a first end of the main exhaust channel is connected with a second end of the transition ejection section and communicates with the intermediate airflow channel;

[0019] The first air circulation machine is arranged in the left stamping outlet channel, and comprises a first fan and a first turbine arranged coaxially, an air inlet pipeline of the first turbine is connected with a hot fluid outlet pipeline of the first air-to-air heat exchanger, and an air outlet pipeline of the first turbine is connected with a cabin air inlet pipeline;

[0020] The second air circulation machine is arranged in the right stamping outlet channel, and comprises a second fan and a second turbine arranged coaxially, an air inlet pipeline of the second turbine is connected with a hot fluid outlet pipeline of the second air-to-air heat exchanger, and an air outlet pipeline of the second turbine is connected with a cabin air inlet pipeline.

[0021] In at least one embodiment of the present application, the stamping inlet section is in a diverging type.

[0022] In at least one embodiment of the present application, a pump, a pressurized expansion assembly, and a gas-liquid separator are arranged on the liquid inlet pipeline of the electronic device.

[0023] In at least one embodiment of the present application, the transition ejection section is in a diverging type.

[0024] In at least one embodiment of the present application,

[0025] The air outlet pipeline of the first turbine is connected with the cabin air inlet pipeline through a wall plate of the stamping outlet section;

[0026] The air outlet pipeline of the second turbine is connected with the cabin air inlet pipeline through a wall plate of the stamping outlet section.

[0027] The present application has at least the following beneficial technical effects:

[0028] The aircraft heat exchange system based on bidirectional ejection of the present application utilizes the principle of constant entropy ejection to limit the flow of ram air entering the left and right stamping outlet channels, and integrates the cold side of the heat exchanger with the ram air inlet, matches the dynamic pressure brought by the ram air with the flow resistance of the heat exchanger group, and effectively avoids problems such as fan overspeed, windmill effect, and surge of the air circulation machine. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1is a schematic diagram of a two-way ejector based aircraft heat exchange system according to an embodiment of the present application.

[0030] wherein:

[0031] 1 - ram inlet section; 2 - air-to-liquid heat exchanger; 3 - ejector slot; 4 - transition ejector section; 5 - left ram exit passage; 6 - right ram exit passage; 7 - main exhaust passage. DETAILED DESCRIPTION

[0032] For the purpose of making the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. Identical or similar labels in the drawings represent identical or similar elements or elements with identical or similar functions. The described embodiments are some embodiments of the present application, not all embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation on the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application. The embodiments of the present application will be described in detail below with reference to the drawings.

[0033] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the scope of protection of the present application.

[0034] The above and other embodiments of the present application will be described in detail below with reference to the drawings. Figure 1 The present application will be described in further detail.

[0035] The present application provides a two-way ejector based aircraft heat exchange system, comprising: a ram air inlet, a heat exchanger and an air circulator, the ram air inlet comprising a ram inlet section 1, a transition ejector section 4 and a ram exit section, the heat exchanger comprising an air-to-liquid heat exchanger 2, a first air-to-air heat exchanger and a second air-to-air heat exchanger, and the air circulator comprising a first air circulator and a second air circulator.

[0036] Specifically, as Figure 1As shown, the first end of the ram inlet section 1 is connected with a ram air duct, and ram air enters the ram inlet section 1 from the first end of the ram inlet section 1. The cold fluid inlet duct of the air-liquid heat exchanger 2 is connected with the second end of the ram inlet section 1, the hot fluid inlet duct of the air-liquid heat exchanger 2 is connected with a liquid outlet duct of the electronic device, and the hot fluid outlet duct of the air-liquid heat exchanger 2 is connected with a liquid inlet duct of the electronic device. The air-liquid heat exchanger 2 is a main accessory of the liquid cooling system and serves the high heat flux density electronic device. The cold side of the air-liquid heat exchanger 2 is in communication with the ram inlet section of the heat exchange system, and the hot side serves as a fluid path of the electronic device after heat exchange. It can be understood that a pump, a pressure expansion assembly, and a gas-liquid separator can be further arranged on the liquid inlet duct of the electronic device.

[0037] The first end of the transition ejector section 4 is connected with the cold fluid outlet duct of the air-liquid heat exchanger 2. The transition ejector section 4 is internally provided with two baffles, which divide the airflow passage in the transition ejector section 4 into a left airflow passage, a middle airflow passage, and a right airflow passage. The end portions of the two baffles and the end portions of the ram outlet section have a predetermined gap therebetween, so as to form an ejector gap 3 in the transition ejector section 4.

[0038] The cold fluid inlet duct of the first air-air heat exchanger is connected with the second end of the transition ejector section 4 and in communication with the left airflow passage, and the hot fluid inlet duct of the first air-air heat exchanger is connected with an engine bleed air duct. The cold fluid inlet duct of the second air-air heat exchanger is connected with the second end of the transition ejector section 4 and in communication with the right airflow passage, and the hot fluid inlet duct of the second air-air heat exchanger is connected with the engine bleed air duct. The air-air heat exchanger is a main accessory of the environmental control system and serves the cabin. The cold side of the air-air heat exchanger is in communication with the ram inlet section of the heat exchange system, and the hot side is a high-temperature gas path from the engine.

[0039] Further, the ram outlet section includes a left ram outlet passage 5, a right ram outlet passage 6, and a main exhaust passage 7. The first end of the left ram outlet passage 5 is connected with the cold fluid outlet duct of the first air-air heat exchanger, the first end of the right ram outlet passage 6 is connected with the cold fluid outlet duct of the second air-air heat exchanger, and the first end of the main exhaust passage 7 is connected with the second end of the transition ejector section 4 and in communication with the middle airflow passage.

[0040] The first air circulation machine is arranged in the left side ram inlet passage 5, and comprises a first fan and a first turbine arranged coaxially, an air inlet pipe of the first turbine is connected with the hot fluid outlet pipe of the first air-air heat exchanger, and an air outlet pipe of the first turbine is connected with the cabin air inlet pipe; the second air circulation machine is arranged in the right side ram inlet passage 6, and comprises a second fan and a second turbine arranged coaxially, an air inlet pipe of the second turbine is connected with the hot fluid outlet pipe of the second air-air heat exchanger, and an air outlet pipe of the second turbine is connected with the cabin air inlet pipe. The air circulation machine introduces the airflow after heat exchange in the air-air heat exchanger into the cabin through the turbine, and discharges the remaining airflow out of the heat exchange system through the fan.

[0041] In the preferred embodiment of the present application, the ram inlet section 1 and the transition ejector section 4 can be arranged in an expanding manner.

[0042] It can be understood that, in the embodiment, the air outlet pipe of the first turbine is connected with the cabin air inlet pipe through the wall plate of the ram outlet section, the air outlet pipe of the second turbine is connected with the cabin air inlet pipe through the wall plate of the ram outlet section, and the airflow is introduced into the cabin through the turbine and the cabin air inlet pipe to serve the cabin.

[0043] The aircraft heat exchange system based on bidirectional ejection of the present application arranges the air-air heat exchanger of the environmental control system and the air-liquid heat exchanger of the liquid cooling system in the airflow passage in communication with each other, reduces the fan end inlet pressure of the air circulation machine by using the flow resistance of the two serial heat exchanger groups, and reduces the probability of fan overspeed and windmill effect; the air-liquid heat exchanger of the liquid cooling system is arranged to have a windward area greater than that of the air-air heat exchanger of the environmental control system, the air-air heat exchanger is arranged downstream of the air-liquid heat exchanger, and a one-third separate exhaust passage is left, which is beneficial to arranging the ejection gap 3.

[0044] The aircraft heat exchange system based on bidirectional ejection of the present application realizes the air conditioning refrigeration capacity mainly by fan suction of environmental air in the ground state, and all the air is discharged through the turbine fan end; in the air state, due to the pressure head of ram air, when the air flow is greater than the flow under the given fan working speed, the fan no longer plays a role in suction of environmental air, the total ram air flow entering the airflow passage is greater than the flow capacity of the fan end, and the fan needs to be speeded up.

[0045] To solve the problems in the prior art, the aircraft heat exchange system based on bidirectional injection of the application is designed as follows: when the air flow is greater than the maximum flow under the given fan working speed, the excess fluid is discharged through structural design to ensure the effective matching of the fan and the pipeline system, thereby solving the problem of fan overspeed; when the air flow is less than the minimum flow under the given fan working speed, the air bypass should be increased through structural design to supplement the fan end flow, so as to ensure the effective matching of the fan and the pipeline system, thereby solving the problem of fan surge; further, the flow resistance of the left side ram exit passage 5, the right side ram exit passage 6 and the main exhaust passage 7 is matched with each other, and the flow resistance of the heat exchanger group of the left side ram exit passage 5 and the right side ram exit passage 6 is used to reduce the problem of overspeed of the fan of the air circulating machine.

[0046] The aircraft heat exchange system based on bidirectional injection of the application increases the injection gap 3 in the transition injection section 4 connected between the air-air heat exchanger of the environmental control system and the air-liquid heat exchanger of the liquid cooling system; when the air flow is too large, because the front side of the air flow passage of the left side ram exit passage 5 and the right side ram exit passage 6 of the environmental control system is provided with the air-air heat exchanger, the flow resistance is slightly larger than that of the main exhaust passage 7, the flow rate in the air flow passage of the left side ram exit passage 5 and the right side ram exit passage 6 is lower than that of the main exhaust passage 7, and the dynamic pressure of the inside of the injection gap 3 (close to the air circulating machine) is higher than that of the outside, so part of the bypass ram air will flow through the injection gap 3 and then be discharged from the main exhaust passage 7, thereby avoiding the entry of too much ram air flow into the fan end to cause fan overspeed and windmill effect; when the air flow is too small, because there is no source of supercharging in the external main exhaust passage 7, the flow rate of the left side ram exit passage 5 and the right side ram exit passage 6 is higher than that of the main exhaust passage 7, and the dynamic pressure of the inside of the injection gap 3 (close to the air circulating machine) is lower than that of the outside, so the air bypass will flow into the injection gap 3 from the main exhaust port of the main exhaust passage 7, and then enter the left side ram exit passage 5 and the right side ram exit passage 6 provided with the air circulating machine to supplement the air, thereby avoiding the entry of too little ram air flow into the fan end of the air circulating machine to cause fan surge. In summary, the application can avoid the adverse effects of fan overspeed, windmill effect, surge and the like, and ensure the safe and stable operation of the system.

[0047] The aircraft heat exchange system based on bidirectional injection of the application uses the principle of constant entropy injection to limit the ram air flow entering the left side and the right side ram exit passage, and integrates the cold side of the heat exchanger with the ram inlet, and matches the dynamic pressure of the ram air with the flow resistance of the heat exchanger group, thereby effectively avoiding the problems of fan overspeed, windmill effect, surge and the like of the air circulating machine.

[0048] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An aircraft heat exchange system based on bidirectional ejector, characterized in that, include: The ram air intake includes a ram air inlet section (1), a transition ejector section (4), and a ram air outlet section; The heat exchanger includes an air-liquid heat exchanger (2), a first air-air heat exchanger, and a second air-air heat exchanger; An air circulator, comprising a first air circulator and a second air circulator; in, The first end of the stamping inlet section (1) is connected to the stamping air pipe; The cold fluid inlet pipe of the air-liquid heat exchanger (2) is connected to the second end of the stamping inlet section (1), the hot fluid inlet pipe of the air-liquid heat exchanger (2) is connected to the drain pipe of the electronic device, and the hot fluid outlet pipe of the air-liquid heat exchanger (2) is connected to the inlet pipe of the electronic device. The first end of the transition ejector section (4) is connected to the cold fluid outlet pipe of the air-liquid heat exchanger (2). The transition ejector section (4) is provided with two baffles. The two baffles divide the airflow channel inside the transition ejector section (4) into a left airflow channel, a middle airflow channel and a right airflow channel. At the same time, there is a predetermined gap between the ends of the two baffles and the ends of the stamping outlet section, thereby forming an ejector slit (3) in the transition ejector section (4). The cold fluid inlet pipe of the first air-to-air heat exchanger is connected to the second end of the transition ejector section (4) and communicates with the left airflow channel. The hot fluid inlet pipe of the first air-to-air heat exchanger is connected to the engine bleed air pipe. The cold fluid inlet pipe of the second air-to-air heat exchanger is connected to the second end of the transition ejector section (4) and communicates with the right airflow channel. The hot fluid inlet pipe of the second air-to-air heat exchanger is connected to the engine bleed air pipe. The stamping outlet section includes a left stamping outlet channel (5), a right stamping outlet channel (6), and a main exhaust channel (7). The first end of the left stamping outlet channel (5) is connected to the cold fluid outlet pipe of the first air-to-air heat exchanger. The first end of the right stamping outlet channel (6) is connected to the cold fluid outlet pipe of the second air-to-air heat exchanger. The first end of the main exhaust channel (7) is connected to the second end of the transition ejector section (4) and communicates with the intermediate airflow channel. The first air circulator is installed in the left-side ram-outlet channel (5). The first air circulator includes a first fan and a first turbine arranged coaxially. The intake pipe of the first turbine is connected to the hot fluid outlet pipe of the first air-to-air heat exchanger, and the exhaust pipe of the first turbine is connected to the cabin intake pipe. The second air circulator is located in the right-side ram air outlet channel (6). The second air circulator includes a second fan and a second turbine arranged coaxially. The intake pipe of the second turbine is connected to the hot fluid outlet pipe of the second air-to-air heat exchanger, and the exhaust pipe of the second turbine is connected to the cabin air intake pipe.

2. The aircraft heat exchange system based on bidirectional ejector according to claim 1, characterized in that, The stamping inlet section (1) is of the expansion type.

3. The aircraft heat exchange system based on bidirectional ejector according to claim 1, characterized in that, The electronic device is equipped with a pump, a pressurization and expansion assembly, and a gas-liquid separator on its liquid inlet pipe.

4. The aircraft heat exchange system based on bidirectional ejector according to claim 1, characterized in that, The transition ejector section (4) is of the expansion type.

5. The aircraft heat exchange system based on bidirectional ejector according to claim 1, characterized in that, The exhaust pipe of the first turbine passes through the wall panel of the ramjet outlet section and connects to the cabin air intake pipe; The exhaust pipe of the second turbine passes through the wall panel of the ramjet outlet section and connects to the cabin air intake pipe.

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