Helium pressurized liquid hydrogen fuel supply system

Abstract

The invention discloses a helium pressurized liquid hydrogen fuel supply system. An outlet of the helium storage tank is connected with a cold side inlet of the primary heat exchanger, and a cold side outlet of the primary heat exchanger is connected with a helium pressurizing opening of the liquid hydrogen storage tank; a first liquid hydrogen pump is arranged in the liquid hydrogen storage tank, an outlet of the first liquid hydrogen pump is connected with a cold side inlet of a secondary heat exchanger through a liquid hydrogen conveying port of the liquid hydrogen storage tank, a cold side outlet of the secondary heat exchanger is connected with an auxiliary power device and an inlet of an engine heat exchanger, and an outlet of the engine heat exchanger is connected with a combustion chamber. The liquid hydrogen conveying port is further connected with a booster pump inlet; a booster pump outlet is connected with an engine heat exchanger inlet through an engine main pump; a hot side inlet of the primary heat exchanger is connected with a heat source outlet of airborne equipment, a hot side outlet of the primary heat exchanger is connected with a hot side inlet of the secondary heat exchanger, and a hot side outlet of the secondary heat exchanger is connected with a heat source inlet of the airborne equipment. The internal pressure of the liquid hydrogen storage tank is controlled through high-pressure helium and waste heat of airborne equipment, and it is guaranteed that the internal pressure of the liquid hydrogen storage tank is within a proper working range under the full flight envelope.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft power, and in particular relates to a helium-pressurized liquid hydrogen fuel supply system. Background Art

[0002] For a certain type of aircraft with special mission requirements, it is necessary to fly for a long time at an altitude of 10,000 meters, which requires the aircraft to have a very high specific fuel consumption, which is determined by the mass energy density of the fuel and the thermal efficiency of the propulsion system. Compared with traditional aviation kerosene, the unit mass energy of liquid hydrogen fuel is 3 times that of aviation kerosene. Its ultra-high mass energy density is very suitable as an energy source for high-altitude and long-flight aircraft.

[0003] When a high-altitude, long-endurance aircraft is cruising, on the one hand, the liquid hydrogen tank will absorb heat from the external environment, causing part of the liquid hydrogen to evaporate and convert into gaseous hydrogen, while increasing the pressure of the liquid hydrogen tank; on the other hand, as the liquid hydrogen is consumed or the gaseous hydrogen is discharged, the pressure inside the liquid hydrogen tank will gradually decrease. If the liquid hydrogen evaporation rate caused by the environmental heat absorbed by the liquid hydrogen tank and the liquid hydrogen consumption rate are fixed and equal, the two will reach a balance to keep the internal pressure of the tank constant. However, due to the complex and changeable actual environment, the evaporation rate of the liquid hydrogen tank absorbing heat will not be completely equal to the supply rate of the propulsion system.

[0004] When the pressure in the liquid hydrogen tank is too high, the high-pressure gas can be released through the safety pressure relief valve to reduce the internal pressure of the tank. However, when the pressure in the liquid hydrogen tank is too low, the liquid hydrogen tank needs to be pressurized, otherwise it will affect the fuel supply of the propulsion system. In this regard, how to maintain a constant pressure in the liquid hydrogen tank is an urgent problem to be solved. Summary of the invention

[0005] The purpose of the present invention is to provide a helium-pressurized liquid hydrogen fuel supply system. The present invention uses high-pressure helium and waste heat from airborne equipment to control the internal pressure of the liquid hydrogen storage tank, ensuring that the internal pressure of the liquid hydrogen storage tank is within a suitable working range under the full flight envelope.

[0006] The technical solution of the present invention is: a helium-pressurized liquid hydrogen fuel supply system, comprising a helium storage tank, the outlet of the helium storage tank is connected to the cold side inlet of a primary heat exchanger, and the cold side outlet of the primary heat exchanger is connected to the helium pressurizing port of the liquid hydrogen storage tank; a first liquid hydrogen pump is arranged inside the liquid hydrogen storage tank, the outlet of the first liquid hydrogen pump is connected to the cold side inlet of a secondary heat exchanger via a liquid hydrogen delivery port of the liquid hydrogen storage tank, the cold side outlet of the secondary heat exchanger is respectively connected to the inlets of an auxiliary power unit and an engine heat exchanger, and the outlet of the engine heat exchanger is connected to a combustion chamber; the liquid hydrogen delivery port is also connected to the inlet of a boosting pump, and the outlet of the boosting pump is connected to the inlet of an engine heat exchanger via an engine main pump; the hot side inlet of the primary heat exchanger is connected to the outlet of a heat source of an airborne device, the hot side outlet of the primary heat exchanger is connected to the hot side inlet of a secondary heat exchanger, and the hot side outlet of the secondary heat exchanger is connected to the inlet of a heat source of an airborne device.

[0007] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a third one-way valve is provided between the cold side outlet of the secondary heat exchanger and the inlet of the engine heat exchanger.

[0008] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, an injection valve is provided between the outlet of the engine heat exchanger and the inlet of the combustion chamber.

[0009] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, the cold side outlet of the secondary heat exchanger is connected to the inlet of the auxiliary power unit via the hydrogen compressor.

[0010] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a first one-way valve is further provided between the outlet of the first liquid hydrogen pump and the liquid hydrogen delivery port of the liquid hydrogen storage tank.

[0011] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a second liquid hydrogen pump is further provided inside the liquid hydrogen storage tank, and the outlet of the second liquid hydrogen pump is connected to the liquid hydrogen delivery port of the liquid hydrogen storage tank via a second one-way valve.

[0012] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, the pressure relief port of the liquid hydrogen storage tank is connected to the inlet of the stop valve, and the outlet of the stop valve is connected to the safety pressure relief valve through a pipeline.

[0013] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a pressure regulating valve is provided between the outlet of the helium storage tank and the cold side inlet of the primary heat exchanger.

[0014] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a first flow regulating valve and a second flow regulating valve are respectively provided between the liquid hydrogen delivery port and the cold side inlet of the secondary heat exchanger, and between the liquid hydrogen delivery port and the booster pump inlet.

[0015] In the aforementioned helium-pressurized liquid hydrogen fuel supply system, a third flow regulating valve is provided between the cold side outlet of the secondary heat exchanger and the inlet of the hydrogen compressor.

[0016] The advantages of the present invention are: the helium-pressurized hydrogen fuel supply system of the present invention carries high-pressure helium and utilizes the waste heat of airborne equipment. When the internal pressure of the liquid hydrogen storage tank is lower than the lower limit of the working pressure, the high-pressure helium of the helium-pressurized system enters the liquid hydrogen storage tank after absorbing the heat of the airborne equipment, thereby increasing the internal pressure of the liquid hydrogen storage tank to a suitable working range; the liquid hydrogen transported by the liquid hydrogen storage tank can provide a cold source for the airborne equipment through a secondary heat exchanger, and the heat-absorbing and vaporized hydrogen enters the engine or auxiliary power unit, and can also be sent to the engine heat exchanger through secondary pressurization, and enter the combustion chamber to burn and do work after absorbing the engine waste heat. Specifically, compared with the prior art, the present invention has the following advantages:

[0017] 1. Aiming at the energy supply demand of high-altitude and long-flight aircraft, the present invention provides a helium-pressurized liquid hydrogen fuel supply system. Compared with the use of traditional aviation kerosene, the mass of liquid hydrogen required to carry is only one-third of that of aviation kerosene, which greatly improves the specific fuel consumption of the aircraft and effectively improves the endurance of the aircraft;

[0018] 2. The present invention provides a helium-pressurized liquid hydrogen fuel supply system. When the internal pressure of the liquid hydrogen storage tank is too high, the high-pressure gas is released through the safety pressure relief valve to reduce the internal pressure of the storage tank. When the internal pressure of the liquid hydrogen storage tank is too low, the internal pressure is maintained within a suitable pressure range by delivering high-temperature and high-pressure helium to the liquid hydrogen storage tank. Compared with the self-pressurization system that relies on the liquid hydrogen storage tank to absorb heat and evaporate to maintain the internal pressure of the storage tank, the internal pressure control of the liquid hydrogen storage tank of the present invention is simpler, more stable and reliable;

[0019] 3. The liquid hydrogen delivered by the liquid hydrogen storage tank to the propulsion system can provide a cold source for the onboard equipment through the onboard equipment heat exchanger, and can also be sent to the engine heat exchanger after secondary pressurization to absorb the engine waste heat. The system makes full use of the available heat sink on the aircraft and avoids the use of ram air to increase flight resistance;

[0020] 4. The high-pressure helium of the helium boosting system of the present invention enters the liquid hydrogen storage tank after absorbing the heat of the airborne equipment. On the one hand, it can act as a heat sink to take away part of the waste heat of the airborne equipment. On the other hand, the heat carried by the high-temperature helium can evaporate part of the liquid hydrogen, thereby increasing the internal pressure of the liquid hydrogen storage tank. It can effectively reduce the use of high-pressure helium to one-half of that of the traditional helium boosting system, thereby improving the feasibility and economy of the helium-boosted liquid hydrogen fuel supply system in aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of a helium-pressurized liquid hydrogen fuel supply system of the present invention;

[0022] Figure markings: 1-helium filling connector, 2-pressure reducing valve, 3-helium storage tank, 4-pressure regulating valve, 5-primary heat exchanger, 6-temperature sensor, 7-first pressure sensor, 8-liquid hydrogen storage tank, 9-first liquid hydrogen pump, 10-first one-way valve, 11-second liquid hydrogen pump, 12-second one-way valve, 13-first flow regulating valve, 14-secondary heat exchanger, 15-third one-way valve, 16-second flow regulating valve, 17-boosting pump, 18-engine main pump, 19-engine heat exchanger, 20-injection valve, 21-combustion chamber, 22-third flow regulating valve, 23-hydrogen compressor, 24-second pressure sensor, 25-auxiliary power unit, 26-stop valve, 27-safety pressure relief valve, 28-airborne equipment heat source. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0025] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] Example 1. Figure 1As shown, a helium-pressurized liquid hydrogen fuel supply system of the present invention includes a helium filling connector 1, a pressure reducing valve 2, a helium storage tank 3, a pressure regulating valve 4, a primary heat exchanger 5, a temperature sensor 6, a first pressure sensor 7, a liquid hydrogen storage tank 8, a first liquid hydrogen pump 9, a first one-way valve 10, a second liquid hydrogen pump 11, a second one-way valve 12, a first flow regulating valve 13, a secondary heat exchanger 14, a third one-way valve 15, a second flow regulating valve 16, a boosting pump 17, an engine main pump 18, an engine heat exchanger 19, an injection valve 20, a combustion chamber 21, a third flow regulating valve 22, a hydrogen compressor 23, a second pressure sensor 24, an auxiliary power unit 25, a stop valve 26, a safety pressure relief valve 27, and an onboard equipment heat source 28. Among them, the liquid hydrogen storage tank 8 is provided with a helium pressurizing port, a pressure releasing port, and a liquid hydrogen delivery port; the primary heat exchanger 5 is provided with a cold side inlet, a cold side outlet, a hot side inlet, and a hot side outlet; the secondary heat exchanger 14 is provided with a cold side inlet, a cold side outlet, a hot side inlet, and a hot side outlet;

[0027] The outlet of the helium storage tank 3 is connected to the pressure regulating valve 4 and the cold side inlet of the primary heat exchanger 5 through a pipeline, and the cold side outlet of the primary heat exchanger 5 is connected to the helium pressurizing port of the liquid hydrogen storage tank 8 through a pipeline;

[0028] The pressure relief port of the liquid hydrogen storage tank 8 is connected to the safety pressure relief valve 27 through a pipeline;

[0029] The first liquid hydrogen pump 9 and the first one-way valve 10 are placed inside the liquid hydrogen storage tank 8, the outlet of the first liquid hydrogen pump 9 is connected to the inlet of the first one-way valve 10 through a pipeline, the outlet of the first one-way valve 10 is connected to the inner side of the liquid hydrogen delivery port of the liquid hydrogen storage tank 8 through a pipeline, the outer side of the liquid hydrogen delivery port of the liquid hydrogen storage tank 8 is connected to the first side of the second three-way pipe through a pipeline, the second side of the second three-way pipe is connected to the inlet of the first flow regulating valve 13 through a pipeline; the third side of the second three-way pipe is connected to the inlet of the second flow regulating valve 16 through a pipeline;

[0030] The outlet of the first flow regulating valve 13 is connected to the inlet of the secondary heat exchanger 14 through a pipeline, the outlet of the secondary heat exchanger 14 is connected to the first side of the third three-way pipe through a pipeline, the second side of the third three-way pipe is connected to the inlet of the third one-way valve 15 through a pipeline; the third side of the third three-way pipe is connected to the third flow regulating valve 22 and the auxiliary power unit 25 through a pipeline;

[0031] The outlet of the second flow regulating valve 16 is connected to the boost pump 17 and the engine main pump 18 through a pipeline; the outlet of the engine main pump 18 is connected to the first side of the fourth three-way pipe through a pipeline, the outlet of the third one-way valve 15 is connected to the second side of the fourth three-way pipe through a pipeline, and the third side of the fourth three-way pipe is connected to the engine heat exchanger 19, the injection valve 20, and the combustion chamber 21 through a pipeline;

[0032] The outlet of the airborne equipment heat source 28 is connected to the hot side inlet of the primary heat exchanger 5 through a pipeline, the hot side outlet of the primary heat exchanger 5 is connected to the hot side inlet of the secondary heat exchanger 14 through a pipeline, and the hot side outlet of the secondary heat exchanger 14 is connected to the inlet of the airborne equipment heat source 28 through a pipeline.

[0033] A helium-pressurized liquid hydrogen fuel supply system also includes a helium filling connector 1 and a pressure reducing valve 2. The helium filling connector 1 is connected to the pressure reducing valve 2 and the inlet of a helium storage tank 3 through a pipeline. When the helium storage tank 3 is a detachable device on an aircraft, the helium filling connector 1 and the pressure reducing valve 2 are not required, and the helium storage tank 3 with sufficient helium can be replaced during ground maintenance. When the helium storage tank 3 is a fixed device on an aircraft, the helium filling connector 1 and the pressure reducing valve 2 are required to fill the helium storage tank 3 on the aircraft with helium during ground maintenance.

[0034] A helium-pressurized liquid hydrogen fuel supply system also includes a temperature sensor 6 and a first pressure sensor 7. The temperature sensor 6 is connected to a sampling port on a pipeline between a cold side outlet of a secondary heat exchanger 5 and a helium pressurizing port of a liquid hydrogen storage tank 8; the first pressure sensor 7 is connected to a sampling port on a pipeline between a cold side outlet of a secondary heat exchanger 5 and a helium pressurizing port of a liquid hydrogen storage tank 8; the temperature sensor 6 collects temperature information of high-temperature and high-pressure helium entering the liquid hydrogen storage tank 5, and the first pressure sensor 7 collects pressure information of high-temperature and high-pressure helium entering the liquid hydrogen storage tank 5, so as to adjust the temperature and flow rate of high-temperature and high-pressure helium entering the liquid hydrogen storage tank 5;

[0035] A helium-pressurized liquid hydrogen fuel supply system also includes a second liquid hydrogen pump 11 and a second one-way valve 12. The second liquid hydrogen pump 11 and the second one-way valve 12 are placed inside a liquid hydrogen storage tank 8, and the outlet of the second liquid hydrogen pump 11 is connected to the inlet of the second one-way valve 12 through a pipeline; the outlet of the first one-way valve 10 is connected to the first side of the first three-way pipe through a pipeline, the outlet of the second one-way valve 12 is connected to the second side of the first three-way pipe through a pipeline, and the third side of the first three-way pipe is connected to the inner side of the liquid hydrogen delivery port of the liquid hydrogen storage tank 8 through a pipeline; wherein the second liquid hydrogen pump 11 and the second one-way valve 12 are backups of the first liquid hydrogen pump 9 and the first one-way valve 10. When the first liquid hydrogen pump 9 fails or fails and cannot normally deliver hydrogen fuel to the propulsion system, the second liquid hydrogen pump 11 starts to work to ensure that the hydrogen fuel in the liquid hydrogen storage tank 8 is stably and reliably delivered to the propulsion system, thereby improving the reliability of the system.

[0036] A helium-pressurized liquid hydrogen fuel supply system also includes a hydrogen compressor 23 and a second pressure sensor 24. The outlet of the third flow regulating valve 22 is connected to the inlet of the hydrogen compressor 23 through a pipeline, and the outlet of the hydrogen compressor 23 is connected to the inlet of the auxiliary power unit 25 through a pipeline; the second pressure sensor 24 is connected to a sampling port on a pipeline between the outlet of the hydrogen compressor 23 and the inlet of the auxiliary power unit 25; the second pressure sensor 24 collects pressure information of hydrogen entering the auxiliary power unit 25 to adjust the rotation speed of the hydrogen compressor 23 so that it increases the hydrogen at the inlet to the pressure range required for the optimal working state of the auxiliary power unit 25;

[0037] A helium-pressurized liquid hydrogen fuel supply system also includes a stop valve 26, the pressure relief port of the liquid hydrogen storage tank 8 is connected to the inlet of the stop valve 26 through a pipeline, and the outlet of the stop valve 26 is connected to the safety pressure relief valve 27 through a pipeline.

[0038] The pressure regulating valve 4 is an electric regulating valve controlled by a pressure signal, which receives the pressure information collected by the first pressure sensor 7. When the pressure information is lower than the lower limit of the working pressure of the liquid hydrogen storage tank 8, the pressure regulating valve 4 opens until the pressure information collected by the first pressure sensor 5 is within the working pressure range of the liquid hydrogen storage tank 8.

[0039] The liquid hydrogen storage tank 8 is a multi-layer insulated storage tank, and the inner and outer walls of the storage tank are vacuum or filled with insulating materials, and the insulating material can be any one of insulating foam, aerogel, and composite insulating materials;

[0040] The first flow regulating valve 13, the second flow regulating valve 16, and the third flow regulating valve 22 are electric regulating valves that can accurately control the valve opening according to the flow requirements of various parts of the system to adjust to a suitable flow;

[0041] The hydrogen engine heat exchange equipment 17 refers to the hydrogen engine turbine blades. Using liquid hydrogen to cool the hydrogen engine turbine blades to increase the turbine inlet gas temperature can effectively improve the engine performance, such as increasing the engine thrust, improving the engine efficiency and power-to-weight ratio.

[0042] The hydrogen compressor 23 is a speed-adjustable compressor, which can adjust the pressure of the hydrogen at the outlet of the third flow control valve 22 according to the pressure requirements of the auxiliary power unit 25 for the inlet hydrogen under different flight conditions, so as to enable the auxiliary power unit 25 to operate efficiently under the best working conditions;

[0043] The auxiliary power unit 25 can be any one of a hydrogen gas turbine, a hydrogen internal combustion engine, and a hydrogen fuel cell. Among them, the use of a hydrogen fuel cell has the advantages of high energy conversion rate and low noise, and can work continuously under the full flight envelope.

[0044] The airborne equipment heat source 28 is the heat dissipation medium of the airborne equipment, which can be any one of the electronic equipment coolant, hydraulic oil, and lubricating oil, to ensure that the electronic equipment, hydraulic system, and generator equipment work stably within a suitable temperature range.

Claims

1. A helium-pressurized liquid hydrogen fuel supply system, characterized in that: The invention comprises a helium storage tank (3), the outlet of the helium storage tank (3) is connected to the cold side inlet of the primary heat exchanger (5), and the cold side outlet of the primary heat exchanger (5) is connected to the helium pressurizing port of the liquid hydrogen storage tank (8); a first liquid hydrogen pump (9) is arranged inside the liquid hydrogen storage tank (8), the outlet of the first liquid hydrogen pump (9) is connected to the cold side inlet of the secondary heat exchanger (14) through the liquid hydrogen delivery port of the liquid hydrogen storage tank (8), and the cold side outlet of the secondary heat exchanger (14) is respectively connected to the inlet of the auxiliary power unit (25) and the engine heat exchanger (19). The outlet of the engine heat exchanger (19) is connected to the combustion chamber (21); the liquid hydrogen delivery port is also connected to the inlet of the boost pump (17), and the outlet of the boost pump (17) is connected to the inlet of the engine heat exchanger (19) through the engine main pump (18); the hot side inlet of the primary heat exchanger (5) is connected to the outlet of the airborne equipment heat source (28), the hot side outlet of the primary heat exchanger (5) is connected to the hot side inlet of the secondary heat exchanger (14), and the hot side outlet of the secondary heat exchanger (14) is connected to the inlet of the airborne equipment heat source (28).

2. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: A third one-way valve (15) is provided between the cold side outlet of the secondary heat exchanger (14) and the inlet of the engine heat exchanger (19).

3. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: An injection valve (20) is provided between the outlet of the engine heat exchanger (19) and the inlet of the combustion chamber (21).

4. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: The cold side outlet of the secondary heat exchanger (14) is connected to the inlet of the auxiliary power unit (25) via the hydrogen compressor (23).

5. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: A first one-way valve (10) is also provided between the outlet of the first liquid hydrogen pump (9) and the liquid hydrogen delivery port of the liquid hydrogen storage tank (8).

6. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: A second liquid hydrogen pump (11) is also provided inside the liquid hydrogen storage tank (8), and the outlet of the second liquid hydrogen pump (11) is connected to the liquid hydrogen delivery port of the liquid hydrogen storage tank (8) via a second one-way valve (12).

7. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: The pressure relief port of the liquid hydrogen storage tank (8) is connected to the inlet of the stop valve (26), and the outlet of the stop valve (26) is connected to the safety pressure relief valve (27) through a pipeline.

8. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: A pressure regulating valve (4) is provided between the outlet of the helium storage tank (3) and the cold side inlet of the primary heat exchanger (5).

9. The helium-pressurized liquid hydrogen fuel supply system according to claim 1, characterized in that: A first flow regulating valve (13) and a second flow regulating valve (16) are respectively provided between the liquid hydrogen delivery port and the cold side inlet of the secondary heat exchanger (14), and between the liquid hydrogen delivery port and the inlet of the booster pump (17).

10. The helium-pressurized liquid hydrogen fuel supply system according to claim 4, characterized in that: A third flow regulating valve (22) is provided between the cold side outlet of the secondary heat exchanger (14) and the inlet of the hydrogen compressor (23).

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