A hydrogen-fueled turbine aeroengine system coupled with a cold energy recovery power cycle

Abstract

The present application relates to the technical fields of aero-engine energy saving and emission reduction, and particularly relates to a hydrogen-fueled turbine aero-engine system coupled with a cold energy recovery power cycle, comprising a gas turbine engine, a liquid hydrogen fuel delivery device, a cold energy recovery device and a transmission device, wherein the gas turbine engine comprises a fan, a compressor, a combustion chamber, a turbine and an engine main shaft; the liquid hydrogen fuel delivery device comprises a liquid hydrogen storage tank, a liquid hydrogen pump, a first expander and a heat exchanger; the cold energy recovery device comprises a working medium pump, a heater, a second expander and a condenser to form a loop; and the transmission device comprises a variable speed gear box and a transmission gear set; the present application can improve the output power of the aero-engine and the energy utilization rate.

Description

Technical Field

[0001] The present invention relates to the technical field of energy conservation and emission reduction of aviation engines, and in particular to a hydrogen-burning turbine aviation engine system coupled with a cold recovery power cycle. Background Art

[0002] Hydrogen energy shows great potential as a green alternative energy source. Compared to other alternative fuels, hydrogen fuel is highly competitive in terms of performance and emissions. It is widely believed that, in the long term, hydrogen energy is the primary technological path to addressing environmental challenges and energy dependence in the aviation industry.

[0003] Hydrogen has a high mass energy density (142MJ / kg) but an extremely low volumetric energy density (5.3MJ / L). To increase storage density within the constraints of aircraft applications, liquid hydrogen storage (20K, 0.1MPa) is necessary. Research has shown that liquid hydrogen combustion must absorb heat and expand to an appropriate temperature and pressure: a temperature of no less than 150K to avoid large density and viscosity fluctuations and partial liquefaction during the fuel's expansion in the injector. Furthermore, to ensure rapid mixing of the fuel with air and prevent flashback, the fuel injection pressure must be higher than the combustion chamber's atmospheric pressure. Liquid hydrogen consumes a significant amount of energy during liquefaction and storage, representing approximately one-third of its calorific value. This energy is released as high-quality cold during the vaporization process. Efficiently utilizing this cold is crucial for energy conservation and emissions reduction in the aviation industry. Summary of the Invention

[0004] In view of the above problems, the present invention provides a hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle, which solves the technical problem in the prior art that the engine output power and energy utilization rate need to be improved in aircraft application scenarios.

[0005] The present invention provides a hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle, comprising a gas turbine engine, a liquid hydrogen fuel delivery device, a cold recovery device, and a transmission device, wherein:

[0006] The gas turbine engine comprises a fan 1, a compressor 2, a combustion chamber 3, a turbine 4 and an engine main shaft 5; the fan 1, the compressor 2 and the turbine 4 are all connected to the engine main shaft 5;

[0007] The liquid hydrogen fuel delivery device includes a liquid hydrogen storage tank 6, a liquid hydrogen pump 7, a first expander 8 and a heat exchanger 9 connected in sequence, and the heat exchanger 9 is connected to the combustion chamber 3;

[0008] The cold recovery device includes a working fluid pump 10, a heater 11, a second expander 12 and a condenser 13. The outlet of the working fluid pump 10 is connected to the cold side inlet of the heater 11, the cold side outlet of the heater 11 is connected to the inlet of the second expander 12, the outlet of the second expander 12 is connected to the hot side inlet of the condenser 13, and the hot side outlet of the condenser 13 is connected to the inlet of the working fluid pump 10, forming a loop;

[0009] The transmission device includes a speed change gearbox 14 and a transmission gear set 15. The input shaft of the speed change gearbox 14 is respectively connected to the first expander 8 and the second expander 12. An output shaft of the speed change gearbox 14 is respectively connected to the liquid hydrogen pump 7 and the working fluid pump 10. The other output shaft is connected to the engine main shaft 5 through the transmission gear set 15.

[0010] Preferably, for the cold recovery device, the hot side of the heater 11 is in contact with the flue gas exhausted by the gas turbine engine; and the cold side of the condenser 13 is in contact with the liquid hydrogen pumped by the liquid hydrogen pump 7 .

[0011] Preferably, for the liquid hydrogen fuel delivery device, the liquid hydrogen fuel flowing out of the liquid hydrogen storage tank 6 passes through the liquid hydrogen pump 7, the condenser 13, the first expander 8, and the heat exchanger 9 in sequence, recovers the cold energy, and then enters the combustion chamber 3 for combustion.

[0012] Preferably, the working fluid of the loop in the cold recovery device is pressurized by the working fluid pump 10 and enters the heater 11 for isobaric heat absorption to become superheated steam, then flows through the second expander 12 to expand and do work, then enters the condenser 13 for isobaric heat release to become saturated liquid, and then flows into the working fluid pump 10 to form a cycle.

[0013] Preferably, a portion of the air at the outlet of the compressor 2 flows into the combustion chamber 3, and another portion of the air flows through the heat exchanger 9 and is cooled.

[0014] Preferably, for the transmission device, the first expander 8 and the second expander 12 drive the liquid hydrogen pump 7 and the working fluid pump 10 to work through the speed change gear box 14, and provide mechanical energy to the engine main shaft 5 through the transmission gear set 15, so as to match the rotational speeds of the liquid hydrogen pump 7, the working fluid pump 10 and the engine main shaft 5.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] (1) The present invention uses engine exhaust as a heat source and liquid hydrogen fuel as a cooling source to construct a Rankine cycle, which has a high energy utilization rate. The cooling energy of the liquid hydrogen circulates to provide shaft power to the engine main shaft, thereby increasing the engine's output power.

[0017] (2) The liquid hydrogen cooling capacity of the present invention can also cool the air at the compressor outlet, reducing the air temperature, thereby improving the cooling efficiency of the engine air system. This cooling effect can improve the performance of the engine, increasing its efficiency and reliability.

[0018] (3) The present invention not only achieves full utilization of liquid hydrogen cooling capacity, but also reduces dependence on other cooling resources, thereby optimizing the resource allocation and utilization efficiency of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings are only for purposes of illustrating particular embodiments and are not to be considered limiting of the invention.

[0020] Figure 1 This is a schematic structural diagram of a hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle provided by the present invention.

[0021] Figure numerals: 1-fan, 2-compressor, 3-combustion chamber, 4-turbine, 5-engine main shaft, 6-liquid hydrogen storage tank, 7-liquid hydrogen pump, 8-first expander, 9-heat exchanger, 10-working fluid pump, 11-heater, 12-second expander, 13-condenser, 14-speed gearbox, 15-transmission gear set. DETAILED DESCRIPTION

[0022] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. 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. In addition, the present invention can also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited by the specific embodiments disclosed below.

[0023] The heat sources that can be used for heat exchange with liquid hydrogen in aircraft engines include air, engine oil, and flue gas. However, due to the ultra-low temperature of liquid hydrogen, the heat source experiences a significant temperature drop during the heat exchange process, potentially causing the engine air to freeze or the engine oil to solidify, which is unacceptable for the engine. Therefore, the present invention uses the higher-temperature engine flue gas as the heat source for the liquid hydrogen vaporization process.

[0024] Due to the large temperature difference between the cold and heat sources, directly exchanging heat between liquid hydrogen and flue gas will produce a large amount of irreversible loss and low cold recovery efficiency. In this regard, the present invention constructs a Rankine cycle, which can greatly reduce the irreversible loss in the heat exchange process and improve the system's efficiency. Efficiency, while the cyclic work is output in the form of shaft work, which is convenient for direct use by the engine.

[0025] In order to illustrate the effectiveness of the method proposed by the present invention, the above technical solution of the present invention is described in detail below through a specific embodiment. Figure 1 As shown, a hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle is disclosed, comprising a gas turbine engine, a liquid hydrogen fuel delivery device, a cold recovery device, and a transmission device, wherein:

[0026] The gas turbine engine comprises a fan 1, a compressor 2, a combustion chamber 3, a turbine 4 and an engine main shaft 5; the fan 1, the compressor 2 and the turbine 4 are all connected to the engine main shaft 5;

[0027] The liquid hydrogen fuel delivery device includes a liquid hydrogen storage tank 6, a liquid hydrogen pump 7, a first expander 8 and a heat exchanger 9 connected in sequence; the heat exchanger 9 is connected to the combustion chamber 3;

[0028] The cold recovery device includes a working fluid pump 10, the outlet of the working fluid pump 10 is connected to the cold side inlet of the heater 11, the cold side outlet of the heater 11 is connected to the inlet of the second expander 12, the outlet of the second expander 12 is connected to the hot side inlet of the condenser 13, and the hot side outlet of the condenser 13 is connected to the inlet of the working fluid pump 10, forming a loop; the hot side of the heater 11 is in contact with the flue gas exhausted by the gas turbine engine; the cold side of the condenser 13 is in contact with the liquid hydrogen pumped by the liquid hydrogen pump 7;

[0029] The transmission device includes a speed change gearbox 14 and a transmission gear set 15. The input shaft of the speed change gearbox 14 is respectively connected to the first expander 8 and the second expander 12. An output shaft of the speed change gearbox 14 is respectively connected to the liquid hydrogen pump 7 and the working fluid pump 10. The other output shaft is connected to the engine main shaft 5 through the transmission gear set 15.

[0030] For the liquid hydrogen fuel delivery device, the liquid hydrogen fuel flowing out of the liquid hydrogen storage tank 6 is pressurized by the liquid hydrogen pump 7 to reach a supercritical state, and then absorbs heat in the condenser 13 to increase the temperature, and then flows through the first expander 8 to expand and do work, reducing the pressure required to enter the combustion chamber, and then further absorbs heat and vaporizes in the heat exchanger 9, raising the temperature to the ambient temperature, and finally enters the combustion chamber 3 for combustion. In the above manner, the liquid hydrogen fuel flowing out of the liquid hydrogen storage tank is pressurized by the liquid hydrogen pump to reach a supercritical state, reducing the average heat exchange temperature difference between it and the working medium, thereby reducing heat exchange losses.

[0031] For the cold recovery device, the heat source is the flue gas discharged by the gas turbine engine, and the cold source is liquid hydrogen fuel. The working fluid is pressurized by the working fluid pump 10 and enters the heater 11 to absorb heat at equal pressure and become superheated steam, then flows through the second expander 12 to expand and do work, and then enters the condenser 13 to release heat at equal pressure and become saturated liquid, and then flows into the working fluid pump 10 to form a cycle.

[0032] For the gas turbine engine, a small portion of the air at the outlet of the compressor 2 is cooled by the heat exchanger 9 and then supplied to the engine air system. In this way, the hydrogen fuel at the outlet of the first expander 8 cools a small portion of the air at the outlet of the compressor through the heat exchanger 9, further utilizing the cooling capacity of the hydrogen. At the same time, the cooled air can provide higher cooling efficiency for the engine air system.

[0033] For the transmission device, the shaft work output by the first expander 8 and the second expander 12 drives the liquid hydrogen pump and the working fluid pump through the speed change gear box 14, and the remaining mechanical energy is provided to the engine main shaft 5 through the transmission gear set 15. The output work of the expander is converted through the speed change gear box and the transmission gear set to match the speed of the pump and the engine main shaft.

[0034] Through the above technical solution, the present invention constructs a Rankine cycle using engine exhaust as the heat source and liquid hydrogen fuel as the cooling source, achieving high energy efficiency. The cooling capacity of the liquid hydrogen, through circulation, provides shaft power to the engine main shaft, increasing the engine's output power. Furthermore, by cooling the compressor outlet air, the cooling efficiency of the engine's air system is enhanced, fully utilizing the cooling capacity of the liquid hydrogen.

[0035] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0036] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0037] In the present invention, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance. The term "plurality" refers to two or more, unless otherwise clearly defined.

[0038] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle, characterized in that: The system includes a gas turbine engine, a liquid hydrogen fuel delivery device, a cold recovery device, and a transmission device, wherein: The gas turbine engine comprises a fan (1), a compressor (2), a combustion chamber (3), a turbine (4) and an engine main shaft (5); the fan (1), the compressor (2) and the turbine (4) are all connected to the engine main shaft (5); The liquid hydrogen fuel delivery device comprises a liquid hydrogen storage tank (6), a liquid hydrogen pump (7), a first expander (8) and a heat exchanger (9) connected in sequence, wherein the heat exchanger (9) is connected to the combustion chamber (3); The cold recovery device comprises a working fluid pump (10), a heater (11), a second expander (12) and a condenser (13), wherein the outlet of the working fluid pump (10) is connected to the cold side inlet of the heater (11), the cold side outlet of the heater (11) is connected to the inlet of the second expander (12), the outlet of the second expander (12) is connected to the hot side inlet of the condenser (13), and the hot side outlet of the condenser (13) is connected to the inlet of the working fluid pump (10), forming a loop; The transmission device includes a speed change gearbox (14) and a transmission gear set (15), wherein an input shaft of the speed change gearbox (14) is connected to the first expander (8) and the second expander (12) respectively, an output shaft of the speed change gearbox (14) is connected to the liquid hydrogen pump (7) and the working fluid pump (10) respectively, and the other output shaft is connected to the engine main shaft (5) through the transmission gear set (15).

2. The hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle according to claim 1, characterized in that: For the cold recovery device, the hot side of the heater (11) contacts the flue gas discharged from the gas turbine engine; the cold side of the condenser (13) contacts the liquid hydrogen pumped by the liquid hydrogen pump (7).

3. The hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle according to claim 2, characterized in that: For the liquid hydrogen fuel delivery device, the liquid hydrogen fuel flowing out of the liquid hydrogen storage tank (6) passes through the liquid hydrogen pump (7), the condenser (13), the first expander (8), and the heat exchanger (9) in sequence, recovers the cold energy, and then enters the combustion chamber (3) for combustion.

4. The hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle according to claim 3, characterized in that: The working fluid in the circuit of the cold recovery device is pressurized by the working fluid pump (10) and enters the heater (11) for isobaric heat absorption to become superheated steam, then flows through the second expander (12) to expand and perform work, then enters the condenser (13) for isobaric heat release to become a saturated liquid, and then flows into the working fluid pump (10) to form a cycle.

5. The hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle according to claim 4, characterized in that: A portion of the air at the outlet of the compressor (2) flows into the combustion chamber (3), and another portion of the air flows through the heat exchanger (9) and is cooled.

6. The hydrogen-fired turbine aircraft engine system coupled with a cold recovery power cycle according to claim 1, characterized in that: In the transmission device, the first expander (8) and the second expander (12) drive the liquid hydrogen pump (7) and the working fluid pump (10) to work through the speed change gear box (14), and provide mechanical energy to the engine main shaft (5) through the transmission gear set (15) for matching the rotational speeds of the liquid hydrogen pump (7), the working fluid pump (10) and the engine main shaft (5).

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