Passive helicopter cabin heating system using lubricating oil waste heat

Abstract

The present application relates to a kind of passive helicopter cabin heating system using lubricating oil waste heat, belong to airborne environmental control system field.The proposed heating system includes lubricating oil system, passive heat transport device and heat exchanger;The lubricating oil system is increased lubricating oil heat releaser in the pipeline of conventional lubricating oil system;The passive heat transport device at least includes shut-off valve, exhaust / liquid filling pipe, evaporator, steam pipeline, temperature control valve, cabin radiator, radiator, liquid pipeline, pressure stabilizing tank, working medium;The evaporator is arranged in the same heat exchanger with lubricating oil heat releaser to realize heat exchange;A certain amount of working medium is injected into passive heat transport device, and finally shut-off valve is closed;Recycling of lubricating oil waste heat is realized by the circulation of working medium in passive heat transport device.The present application solves the problem of cabin heating on engine performance, with low compensation, high energy efficiency characteristics, while also having good maintainability.

Description

TECHNICAL FIELD

[0001] The application relates to a helicopter cabin heating system and belongs to the field of airborne environmental control systems. BACKGROUND

[0002] Helicopters need to work in a low-temperature high-altitude environment with a temperature as low as dozens of degrees below zero. In order to ensure the comfort of the crew and passengers, the cabin needs to be heated. At present, the main method of heating the helicopter cabin is engine bleed air heating, and the bleed air can significantly reduce the speed and maneuverability of the helicopter and increase the engine fuel compensation loss. In the future, helicopters will have higher and higher requirements for speed and range, and high speed will exacerbate the loss of heat in the cabin in a low-temperature environment, further increasing the demand for bleed air, thereby increasing the impact on the engine. Therefore, a heating system with high energy efficiency, low fuel compensation loss and low system operation cost needs to be sought.

[0003] In some existing heat recovery heat exchange structures, patent CN104454455A and CN203548122U disclose an air compressor lubricating oil waste heat recovery heat pipe heat exchanger, which uses a heat pipe as a heat conduction structure inside the heat exchanger and is only used for simple heat exchange inside the heat exchanger; patent CN101555815A discloses a lubricating oil waste heat recovery method for an internal combustion engine; patent CN114353379A discloses a carbon dioxide heat pump system with lubricating oil waste heat recovery; patent CN101408115B discloses a heat cycle system suitable for waste heat recovery of a vehicle engine; patent CN207482197U discloses a cabin heating system for recovering engine exhaust heat; patent CN114044147A discloses a heat management system and control method based on engine exhaust heat recovery; and patent CN114180071A discloses a heating system using lubricating oil as an auxiliary heat source. Although these disclosed patent technologies propose the design idea of engine waste heat recovery, the heat cycle form needs to be assisted by other power equipment, in other words, although the purpose of energy recycling is achieved to some extent, since a positive heat exchange design is adopted, external energy still needs to be consumed.

[0004] The heat load of the helicopter lubricating oil cooling system is as high as several hundred kilowatts, which needs to be discharged outside the cabin through the lubricating oil radiator. Without consuming the helicopter's own kinetic energy, if the heat of the lubricating oil system is recovered to heat the cabin, the heat performance of the engine can be ensured not to be affected, and the heat load of the lubricating oil radiator and the fan power consumption can be reduced. SUMMARY

[0005] The purpose of the application is to realize the recovery and reuse of the heat of the helicopter lubricating oil cooling system, and a passive helicopter cabin heating system using lubricating oil waste heat is proposed.

[0006] The technical scheme of the present application: a passive helicopter cabin heating system using lubricating oil waste heat, which mainly comprises a lubricating oil system, a passive heat transport device and a heat exchanger; the lubricating oil system adds a lubricating oil heat releaser in the pipeline of the traditional lubricating oil system; the passive heat transport device at least includes a shut-off valve, an exhaust / liquid charging pipe, an evaporator, a steam pipeline, a temperature control valve, a cabin radiator, a radiator, a liquid pipeline, a pressure stabilizing tank and a working medium; the evaporator and the lubricating oil heat releaser are arranged in the same heat exchanger to realize heat exchange, the evaporator is connected to the temperature control valve through the steam pipeline, and then is divided into two paths, one of which is connected to the cabin radiator and the other of which is connected to the radiator; the two pipelines are then merged into the evaporator through the liquid pipeline; the shut-off valve, the exhaust / liquid charging pipe and the pressure stabilizing tank are arranged on the liquid pipeline; before use, the shut-off valve is opened, the passive heat transport device is vacuumized through the exhaust / liquid charging pipe, a certain amount of working medium is injected after all the internal gases are discharged (the volume of the working medium is less than 100% of the internal space volume of the heat transport device), and finally the shut-off valve is closed, so that the working medium circulates in the passive heat transport device to realize the reuse of lubricating oil waste heat.

[0007] Optionally, the lubricating oil heat releaser adopts a serpentine pipe structure to improve the heat exchange efficiency.

[0008] Optionally, the evaporator internally adopts a metal material porous structure to improve the heat exchange efficiency.

[0009] Optionally, a porous capillary structure is added to the liquid pipeline to the evaporator pipeline to assist the liquid backflow and improve the heat exchange efficiency.

[0010] Optionally, the cabin radiator is arranged at a position higher than that of the evaporator, so that the condensed liquid is more easily backflowed under the action of gravity.

[0011] Optionally, the heat exchanger is filled with a phase change material, and the evaporator and the lubricating oil heat releaser must be completely immersed in the phase change material.

[0012] Optionally, high-thermal-conductivity nano particles are added to the phase change material to improve the heat exchange performance.

[0013] Optionally, the evaporator can adopt a plurality of parallel groups, which can improve the heat exchange efficiency and serve as a backup.

[0014] The working principle of the application is as follows: the lubricating oil in the lubricating oil system flows through the lubricating oil heat releaser, and then the heat is transferred to the evaporator of the heat transport device through the heat exchanger; the medium of the heat exchanger is a phase change material, and the evaporator and the lubricating oil heat releaser must be completely immersed in the phase change material, so that the temperature of the evaporator is more stable. The liquid working medium in the evaporator is evaporated into steam after being heated, and the steam flows along the steam pipeline to the temperature control valve. The working medium flows to the cabin radiator through the temperature control valve, and the other working medium enters the radiator. The temperature control valve controls the opening of the valve according to the temperature in the cabin, so as to adjust the flow of the working medium entering the cabin radiator. The steam working medium entering the cabin radiator releases heat to the cabin, so as to warm the cabin, and the working medium is condensed into liquid. The remaining steam working medium flows to the radiator, and the heat is taken away by the lubricating oil cooling fan, and the working medium is condensed into liquid. The working medium after passing through the cabin radiator and the radiator is combined and flows back to the evaporator through the liquid pipeline, so as to complete the cycle. The pressure stabilizing tank is located on the liquid pipeline, and is used to maintain the stable pressure in the heat transport device. Through this cycle, the heat of the lubricating oil can be passively transferred to the cabin.

[0015] The application has the following advantages: the application utilizes the evaporation and condensation cycle mechanism of the working medium, the working medium is self-circulated in the passive heat transport device, and the heat exchange is realized through the state change, so that the waste heat of the lubricating oil is passively recovered to the cabin of the helicopter for warming, and the temperature of the cabin is effectively controlled through the temperature control valve. The evaporation / condensation process of the working medium absorbs / releases latent heat, so that the system has the characteristics of high heat transfer efficiency; the flow of the working medium does not need additional power assistance, so that the system has the characteristics of simple structure and low operation cost. In addition, compared with the traditional bleed air warming, the application solves the problem of the influence of cabin warming on the performance of the engine, has the characteristics of low compensation and high energy efficiency, and has good maintainability. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 FIG. 1 is a schematic diagram of a passive helicopter cabin warming system utilizing lubricating oil waste heat,

[0017] In the figure, 1 is a lubricating oil system, 101 is a lubricating oil heat releaser, 102 is a lubricating oil radiator, 103 is a lubricating oil cooling fan, 2 is a passive heat transport device, 201 is a shut-off valve, 202 is an exhaust / liquid filling pipe, 203 is an evaporator, 204 is a steam pipeline, 205 is a temperature control valve, 206 is a cabin radiator, 207 is a radiator, 208 is a liquid pipeline, 209 is a pressure stabilizing tank, 210 is a working medium, 3 is a heat exchanger, 301 is a phase change material, and 4 is a cabin. DETAILED DESCRIPTION

[0018] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0019] Referring to the drawings Figure 1 A schematic diagram of a specific design of a passive helicopter cabin heating system using oil waste heat. The system mainly includes an oil system 1, a passive heat transport device 2 and a heat exchanger 3. The oil system 1 increases an oil heat releaser 101 in the pipeline of the conventional oil system; in order to improve the heat exchange efficiency, the oil heat releaser 101 is changed from the original straight pipeline to a serpentine pipeline. The passive heat transport device 2 in the heating system includes a shut-off valve 201, an exhaust / liquid charging pipe 202, an evaporator 203, a steam pipeline 204, a temperature control valve 205, a cabin radiator 206, a radiator 207, a liquid pipeline 208, a pressure stabilizing tank 209 and a working medium 210. The radiator 207 of the heat transport device 2 is assembled with the oil cooling fan 103. Before use, the shut-off valve 201 is opened, the passive heat transport device 2 is vacuumized through the exhaust / liquid charging pipe 202, after all the internal gases are discharged, a certain amount of working medium 210 is injected (the volume of the working medium 210 is less than 100% of the internal space volume of the heat transport device), and finally the shut-off valve 201 is closed. The working medium 210 is self-circulated in the passive heat transport device 2, and heat exchange is realized through state change.

[0020] The circulation process of the working medium 210 in the passive heat transport device 2 is as follows: the liquid working medium 210 in the evaporator 203 is evaporated into steam after being heated, and the steam flows along the steam pipeline 204 to the temperature control valve 205. The working medium 210 passing through the temperature control valve 205 flows to the cabin radiator 206 in one way and enters the radiator 207 in the other way. The temperature control valve 205 controls the opening degree of the valve through the temperature in the cabin 4, so as to adjust the flow of the working medium entering the cabin radiator 206. The steam working medium entering the cabin radiator 206 releases heat to the cabin 4, so as to achieve the purpose of heating the cabin, and the working medium is condensed into liquid. The remaining steam working medium flows to the radiator 207, and the heat is taken away by the oil cooling fan 103, and the working medium is condensed into liquid. The working medium after passing through the cabin radiator 206 and the radiator 207 is combined and flows back to the evaporator 203 through the liquid pipeline 208, so as to complete the circulation. The pressure stabilizing tank 209 is located on the liquid pipeline, and is used to maintain the stable pressure in the heat transport device 2. Through this circulation, the heat of the oil can be passively transferred to the cabin 4.

[0021] In the specific design, in order to further enhance the heat exchange efficiency, the metal material porous structure is adopted inside the evaporator 203 in the passive heat transport device 2; meanwhile, the porous capillary structure is added in the liquid pipeline 208 to the pipeline of the evaporator 203, which can assist the liquid backflow. In the device, the position of the cabin radiator 206 is higher than that of the evaporator 203, so that the condensed liquid working medium is more easily backflowed under the action of its own gravity.

[0022] The oil system 1 exchanges heat with the passive heat transport device 2 through the heat exchanger 3, the working medium of the heat exchanger 3 adopts the phase change material 301, and the evaporator 203 and the oil heat radiator 101 must be completely immersed in the phase change material 301, so that the temperature of the evaporator 203 is more stable. Meanwhile, the evaporator can adopt the form of multiple parallel groups, which can improve the heat exchange efficiency on the one hand and back up each other on the other hand. High-thermal-conductivity nano particles are added in the phase change material 301 to further enhance the heat exchange performance.

[0023] In the specific design process, in order to improve the heat exchange efficiency of the heating system, the further design forms can further include that the oil heat radiator in the system adopts the serpentine pipe structure form; the metal material porous structure is adopted inside the evaporator; the porous capillary structure is added in the liquid pipeline to the pipeline of the evaporator, which can assist the liquid backflow; in addition, the high-thermal-conductivity nano particles are added in the phase change material, and the evaporator can adopt the form of multiple parallel groups. The above design forms can be selected, or multiple combinations can be made according to the use scene.

[0024] The heat carrying capacity of the helicopter oil cooling system is as high as several hundred kilowatts, which needs to be discharged outside the cabin through the oil radiator. If the heat of the oil recovery system is used to heat the cabin, not only the engine thermal performance can be ensured, but also the heat load of the oil radiator and the fan power consumption can be reduced. The oil in the helicopter oil system 1 flows through the oil heat radiator 101, and then the heat is transmitted to the evaporator 203 of the heat transport device 2 through the heat exchanger 3. The working medium of the heat exchanger 3 adopts the phase change material 301, and the evaporator 203 and the oil heat radiator 101 must be completely immersed in the phase change material 301, so that the temperature of the evaporator 203 is more stable. The above is only a specific embodiment of the present application, which is described in detail, and the part not described in detail is the conventional technology. However, the protection scope of the present application is not limited to this, any change or replacement within the technical range disclosed by the present application can be easily thought by those skilled in the art, which should be covered in the protection scope of the present application. The protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A passive helicopter cabin heating system utilizing lubricating oil waste heat, characterized in that, The heating system comprises an oil system, a passive heat transport device and a heat exchanger; the oil system is provided with an oil heat releaser in a pipeline of a conventional oil system; the passive heat transport device comprises at least a shut-off valve, an exhaust / liquid charging pipe, an evaporator, a steam pipeline, a temperature control valve, a cabin radiator, a radiator, a liquid pipeline, a pressure stabilizer and a working medium; the evaporator and the oil heat releaser are arranged in the same heat exchanger to realize heat exchange; the evaporator is connected to the temperature control valve through the steam pipeline and then divided into two branches, one of which is connected to the cabin radiator and the other is connected to the radiator; the two branches are merged into the evaporator through the liquid pipeline; the shut-off valve, the exhaust / liquid charging pipe and the pressure stabilizer are arranged on the liquid pipeline; before use, the shut-off valve is opened, the passive heat transport device is vacuumized through the exhaust / liquid charging pipe, all the gas in the passive heat transport device is discharged, a certain amount of working medium is injected, and finally the shut-off valve is closed; the working medium circulates in the passive heat transport device to realize the reuse of the oil waste heat; The oil in the oil system flows through the oil heat releaser, and heat is transferred to the evaporator of the heat transport device through the heat exchanger; the medium of the heat exchanger is a phase change material, and the evaporator and the oil heat releaser must be completely immersed in the phase change material, so that the temperature of the evaporator is more stable; the liquid working medium in the evaporator is evaporated into steam after being heated, and the steam flows to the temperature control valve along the steam pipeline; the working medium passes through the temperature control valve and flows to the cabin radiator in one way and enters the radiator in the other way; the temperature control valve controls the opening degree of the valve according to the temperature in the cabin, so as to adjust the flow of the working medium into the cabin radiator; the steam working medium entering the cabin radiator releases heat to the cabin, so as to warm the cabin, and the working medium is condensed into liquid; the remaining steam working medium flows to the radiator, and the heat is taken away by the oil cooling fan, and the working medium is condensed into liquid; the working medium after passing through the cabin radiator and the radiator is merged and flows back to the evaporator through the liquid pipeline, completing the circulation; the pressure stabilizer is arranged on the liquid pipeline to maintain the stable pressure in the heat transport device; through this circulation, the heat of the oil can be passively transferred to the cabin.

2. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 1, wherein, The heat exchanger is filled with phase change material, and the evaporator and the oil heat releaser are completely immersed in the phase change material.

3. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 2, wherein, High-thermal-conductivity nano particles are added to the phase change material.

4. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 1, wherein, The oil heat releaser adopts a serpentine pipe structure.

5. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 1, wherein, The evaporator can adopt a plurality of parallel groups.

6. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 5, wherein, The evaporator is internally provided with a metal material porous structure.

7. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 1, wherein, A porous capillary structure is added to the liquid pipeline to the evaporator pipeline to assist the liquid backflow.

8. A passive helicopter cabin heating system utilizing lubricating oil waste heat as claimed in claim 1, wherein, The cabin radiator is arranged at a position higher than that of the evaporator.

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