Multi-stage cell structure hydrogen fuel nozzle and staged combustion control method thereof

Abstract

This invention discloses a multi-stage cellular structure hydrogen fuel nozzle and its staged combustion control method, belonging to the field of hydrogen energy power technology. The nozzle includes at least one central duty combustion unit and multiple surrounding main combustion stage combustion units. Each combustion unit contains multiple independent combustion structures arranged from the inside out, with air cooling channels formed between stages. Each combustion stage integrates lattice cellular structures and TPMS cellular structures. The method, through independently controlled hydrogen fuel supply channels, activates only the first stage of the duty combustion unit to form a diffusion-stabilized flame at low loads. At medium to high loads, it activates each stage of the main combustion stage and other stages of the duty combustion unit as needed for premixed combustion, forming an isolation layer in conjunction with cooling air. This invention effectively solves the NO₂ problem in hydrogen fuel combustion. x The problems of high emissions, easy backfire, and poor adaptability to operating conditions have been solved, achieving efficient, stable, and low-emission combustion.

Description

Technical Field

[0001] This invention relates to the field of hydrogen energy power technology, specifically to a multi-stage cellular structure hydrogen fuel nozzle and its staged combustion control method, applicable to hydrogen fuel combustion equipment such as hydrogen fuel engines and hydrogen gas turbines. Background Technology

[0002] Hydrogen fuel, as an ideal zero-carbon emission fuel, is attracting increasing attention for its application in aerospace, automotive, and power generation. However, existing hydrogen fuel combustion technologies and nozzle designs still face the following challenges in engineering practice:

[0003] High nitrogen oxides (NO) x Emissions Issues: Hydrogen fuel exhibits high flame propagation speed and high adiabatic flame temperature, resulting in high combustion flame temperatures and the formation of localized high-temperature zones. Within these high-temperature zones, nitrogen (N2) in the air readily reacts with oxygen (O2) to produce thermal NO. x Combustion is a major obstacle to achieving ultra-low emissions in hydrogen fuel cell engines and gas turbines. Traditional lean or rich combustion schemes often struggle to simultaneously achieve both combustion efficiency and emission performance, and are prone to combustion instability.

[0004] Backfire risk: Hydrogen (i.e., hydrogen fuel) burns much faster than traditional fossil fuels. Its high diffusion coefficient and low minimum ignition energy make it highly susceptible to backfire propagation into the nozzle, causing backfire. Backfire not only burns nozzle components but can also lead to safety accidents in the entire combustion system, making it a critical safety hazard that must be overcome in the design of hydrogen combustion systems. Existing backfire prevention strategies typically rely on increasing flow rate or using porous media, but these can lead to significant pressure losses or structural limitations.

[0005] Poor combustion uniformity and stability: The mixing process of hydrogen and air is crucial to combustion performance. Incomplete or uneven mixing leads to uneven flame temperature distribution, hot spots, and consequently increases NO content. x Emissions are a concern; furthermore, an unstable mixing process can lead to combustion oscillations, flameout, and other problems, affecting the performance, efficiency, and lifespan of hydrogen fuel cell engines. Moreover, combustion stability is a significant challenge when operating under varying conditions or low loads.

[0006] The combustion control lacks flexibility: existing hydrogen fuel injectors mostly adopt fixed or roughly zoned combustion modes, making it difficult to make fine and highly flexible combustion adjustments according to changes in engine operating conditions (such as start-up, variable load, and steady-state operation). This limits its adaptability, fuel economy, and emission optimization potential over a wide range of operating conditions.

[0007] Therefore, the design of current hydrogen fuel combustion nozzles urgently needs innovation to provide a solution that can simultaneously address NO2 issues. xA new type of nozzle designed to address issues such as emissions, backfire, uneven and unstable combustion, and inflexible combustion control. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention aims to provide a multi-stage cellular structure hydrogen fuel nozzle and its staged combustion control method to solve the problem of NO in hydrogen fuel combustion. x Problems include high emissions, susceptibility to backfire, poor combustion uniformity, and lack of control flexibility.

[0009] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a multi-stage cellular structure hydrogen fuel nozzle, comprising at least one central duty combustion unit and multiple main combustion stage combustion units surrounding the duty combustion unit. Each combustion unit comprises multiple (preferably three) independent combustion structures sequentially wrapped from the inside out, and air cooling channels are formed between adjacent stages and outside the outermost stage. Each stage of the combustion structure integrates two cellular structures with different functions:

[0011] Lattice cell structure: used for hydrogen fuel pretreatment. In each stage of the main combustion unit and in the non-first stage combustion structure of the standby combustion unit, openings are formed on the outer wall of the front end to introduce air and hydrogen for thorough premixing, forming a premixed gas. This aims to reduce combustion temperature and suppress NO from the source. x Generation; In the first level of the duty shift, its front outer wall has no opening groove, and is only used for hydrogen partial pressure and flow stabilization, which is intended to ensure the stability of the diffusion flame at low load.

[0012] TPMS (Triple Period Minimal Surface) cell structure: Located downstream of the lattice cell structure, it is used to support the flow of hydrogen fuel or premixed gas and achieve multifunctional integration. Its unique three-dimensional continuous channel structure allows the fuel gas (premixed gas or hydrogen) and cooling air to flow independently and without interference. Cooling air flows through its walls with a very large specific surface area, achieving efficient cooling of the structure; at the same time, its complex and tortuous microchannels can effectively impede flame propagation and suppress backfire.

[0013] Secondly, this invention provides a staged combustion control method for the aforementioned hydrogen fuel nozzle. This method supplies hydrogen fuel independently to each stage of the combustion unit via independent fuel supply channels (such as a multi-stage gas supply ring chamber and solenoid valve system). The control unit (such as a PLC) intelligently switches between different combustion modes according to the engine load conditions.

[0014] Low load condition: Only the first stage of combustion structure is activated to form a stable diffusion flame core.

[0015] Medium and high load conditions: Based on operating requirements, activate each stage of the main combustion stage and the corresponding stage of the on-duty combustion system to achieve high efficiency and low NO₂ levels. x Premixed combustion of emissions.

[0016] Throughout the process, cooling air is continuously introduced through the TPMS cell structure for cooling and to suppress tempering, while an air isolation layer is used to avoid mutual interference between flames at different levels and units.

[0017] Compared with the prior art, the multi-stage cellular structure hydrogen fuel nozzle and its staged combustion control method provided by the present invention can produce at least the following beneficial effects:

[0018] Low NO x Emissions: The lattice cell structure ensures uniform premixing, while the TPMS cell structure enhances cooling. This dual approach effectively reduces flame temperature and suppresses NO. x generate.

[0019] Highly effective suppression of backfire: The unique structure of TPMS cells provides significant resistance to the reverse propagation of flames, fundamentally improving safety.

[0020] Stable and uniform combustion: Through multi-stage structure, air isolation layer and shift diffusion flame design, the combustion stability and temperature uniformity are ensured under all operating conditions.

[0021] Flexible and precise control: Through a graded independent hydrogen supply and control strategy, the nozzle can adapt to a wide range of operating conditions from start-up and low load to high load, and always maintain optimal condition.

[0022] Compact and lightweight: The cellular structure is suitable for additive manufacturing, enabling the integrated molding of complex functional structures while reducing weight. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the multi-level cellular structure hydrogen fuel nozzle provided in an embodiment of the present invention;

[0024] Figure 2 yes Figure 1 The exploded view of the structure shown illustrates the main components and their assembly relationships.

[0025] Figure 3 This is a cross-sectional view of the overall structure of the multi-level cellular structure hydrogen fuel nozzle provided in an embodiment of the present invention;

[0026] Figure 4 This is a cross-sectional view of the three-stage layered structure of a single main combustion stage combustion unit provided in an embodiment of the present invention;

[0027] Figure 5This is a three-level layered structural cross-sectional view of a single duty combustion unit provided in an embodiment of the present invention;

[0028] Figure 6 This is an inlet end view of the hydrogen fuel combustion nozzle provided in an embodiment of the present invention;

[0029] Figure 7 This is a view of the outlet end of the hydrogen fuel combustion nozzle provided in an embodiment of the present invention;

[0030] Figure 8 This is a simulation diagram of the nozzle outlet temperature distribution under hot conditions provided in an embodiment of the present invention for a hydrogen fuel combustion nozzle;

[0031] Figure 9 The hot-state NO at the nozzle outlet of the hydrogen fuel combustion nozzle provided in this embodiment of the invention is... X Simulation diagram of emission distribution;

[0032] Figure 10 This is a simulation diagram of the OH radical distribution at the nozzle outlet under hot conditions provided in an embodiment of the present invention.

[0033] In the diagram, 100 - duty combustion unit, 200 - main combustion stage combustion unit, 300 - hydrogen fuel supply ring cavity, 110 - first-stage duty combustion structure, 120 - second-stage duty combustion structure, 130 - third-stage duty combustion structure, 210 - first-stage main combustion stage combustion structure, 220 - second-stage main combustion stage combustion structure, 230 - third-stage main combustion stage combustion structure, 310 - first hydrogen supply ring cavity, 320 - second hydrogen supply ring cavity, 330 - third hydrogen supply ring cavity, 311 - first hydrogen supply channel, 321 - second hydrogen supply channel, 331 - third hydrogen supply channel, 111 - first-stage duty hydrogen supply pipeline, 1 21 - Second-level duty hydrogen supply pipeline, 131 - Third-level duty hydrogen supply pipeline, 112 - First-level duty hydrogen fuel tank, 122 - Second-level duty hydrogen fuel tank, 132 - Third-level duty hydrogen fuel tank, 113 - First-level duty lattice cell structure, 123 - Second-level duty lattice cell structure, 133 - Third-level duty lattice cell structure, 114 - First-level duty TPMS cell structure, 125 - Second-level duty TPMS cell structure, 135 - Third-level duty TPMS cell structure, 115 - First-level duty air chamber, 126 - Second-level duty air chamber, 136 - Third duty air compartment, 116- First duty air vent, 127- Second duty air vent, 137- Third duty air vent, 124- Second duty opening slot, 134- Third duty opening slot, 211- First stage main combustion hydrogen supply pipeline, 221- Second stage main combustion hydrogen supply pipeline, 231- Third stage main combustion hydrogen supply pipeline, 212- First stage main combustion hydrogen fuel compartment, 222- Second stage main combustion hydrogen fuel compartment, 232- Third stage main combustion hydrogen fuel compartment, 213- First stage main combustion lattice cell structure, 223- Second stage main combustion lattice cell structure, 233- Third stage main combustion hydrogen fuel compartment Combustion stage lattice cell structure, 214-first stage main combustion stage opening slot, 224-second stage main combustion stage opening slot, 234-third stage main combustion stage opening slot, 215-first stage main combustion stage TPMS cell structure, 225-second stage main combustion stage TPMS cell structure, 235-third stage main combustion stage TPMS cell structure, 216-first stage main combustion stage air compartment, 226-second stage main combustion stage air compartment, 236-third stage main combustion stage air compartment, 217-first stage main combustion stage air vent, 227-second stage main combustion stage air vent, 237-third stage main combustion stage air vent, 240-total air compartment, 241-reinforcing rib, 242-cooling vent. Detailed Implementation

[0034] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0035] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] This invention provides a multi-stage cellular structure hydrogen fuel nozzle, comprising: at least one center-level combustion unit and multiple main combustion units surrounding the center-level combustion unit. (See also...) Figures 1-6 The nozzle head adopts a ring array layout. In this embodiment, it includes a centrally located duty combustion unit 100 and six main combustion stage combustion units 200 evenly distributed around it. This layout is beneficial for forming a stable and symmetrical combustion field and making full use of space. The number of duty combustion units and main combustion stage combustion units can be set according to actual needs and is not limited to the aforementioned number.

[0037] Each of the aforementioned combustion units comprises a multi-stage independent combustion structure, which is sequentially arranged from the inside out, forming air cooling channels between adjacent stages and outside the outermost stage. In this embodiment, both the duty combustion unit 100 and the main combustion unit 200 adopt a three-stage concentric nested independent combustion structure, which is the basis for achieving staged combustion. The duty combustion unit 100 includes a first-stage duty combustion structure 110, a second-stage duty combustion structure 120, and a third-stage duty combustion structure 130, and the main combustion unit 200 includes a first-stage main combustion structure 210, a second-stage main combustion structure 220, and a third-stage main combustion structure 230. The distribution of each stage in the duty combustion unit 100 and the main combustion unit 200 is as follows:

[0038] The first stage: located at the very center of the combustion unit, it is cylindrical and is the core area for hydrogen fuel premixing or initial combustion.

[0039] The second stage: encloses the first stage and is cylindrical in shape. A first annular cylindrical air cooling channel is formed between the first stage and the second stage. For example, the first main combustion stage cooling channel formed between the first-stage main combustion stage combustion structure 210 and the second-stage main combustion stage combustion structure 220, and the first duty-shift cooling channel formed between the first-stage duty-shift combustion structure 110 and the second-stage duty-shift combustion structure 120.

[0040] The third stage: encloses the second stage and is cylindrical in shape. A second annular cylindrical air cooling channel is formed between the second and third stages, such as the second main combustion stage cooling channel formed between the second main combustion stage combustion structure 220 and the third main combustion stage combustion structure 230, and the second duty cooling channel formed between the second duty combustion stage combustion structure 120 and the third duty combustion stage combustion structure 130.

[0041] In addition to the third stage, there is a ring of cylindrical shell-shaped air cooling channels, such as the third main combustion stage cooling channel outside the third main combustion stage combustion structure 230, and the third duty cooling channel outside the third duty combustion stage combustion structure 130.

[0042] These air cooling channels guide cooling air and provide physical isolation and cooling for each stage of the combustion structure. This multi-stage concentric shell structure not only achieves staged combustion and spatial optimization, but more importantly, it provides the physical basis for independent management of internal gases, precise cooling, and flame isolation.

[0043] To achieve staged independent hydrogen supply, embodiments of the present invention preferably include a three-stage independent coaxial hydrogen fuel supply ring cavity, such as... Figures 1-6 As shown, the three-stage independent hydrogen fuel supply ring cavity 300 includes a first hydrogen supply ring cavity 310, a second hydrogen supply ring cavity 320 and a third hydrogen supply ring cavity 330. The hydrogen fuel supply ring cavity is coaxially distributed with the hydrogen fuel nozzle and is used to independently supply hydrogen fuel to the different levels of combustion structures of the duty combustion unit 100 and the main combustion unit 200.

[0044] The first hydrogen supply annular cavity 310, also known as the first-stage hydrogen annular cavity, is located at the front and close to the combustion unit. The first-stage standby combustion structure 110 is connected to the first hydrogen supply annular cavity 310 through the first-stage standby hydrogen supply pipe 111, and the first-stage main combustion stage combustion structure 210 is connected to the first hydrogen supply annular cavity 310 through the first-stage main combustion hydrogen supply pipe 211; thus supplying hydrogen to the first-stage combustion structures of all combustion units.

[0045] The second hydrogen supply annular cavity 320, also known as the second-stage hydrogen annular cavity, is located in the middle. The second-stage standby combustion structure 120 is connected to the second hydrogen supply annular cavity 320 via the second-stage standby hydrogen supply pipe 121, and the second-stage main combustion stage combustion structure 220 is connected to the second hydrogen supply annular cavity 320 via the second-stage main combustion hydrogen supply pipe 221; thus supplying hydrogen to the second-stage combustion structures of all combustion units.

[0046] The third hydrogen supply annular cavity 330, also known as the third-stage hydrogen annular cavity, is located at the rear, away from the combustion unit. The third-stage standby combustion structure 130 is connected to the third hydrogen supply annular cavity 330 via the third-stage standby hydrogen supply pipe 131, and the third-stage main combustion stage combustion structure 230 is connected to the third hydrogen supply annular cavity 330 via the third-stage main combustion hydrogen supply pipe 231; thus supplying hydrogen to the third-stage combustion structures of all combustion units.

[0047] The first hydrogen supply annular cavity 310, the second hydrogen supply annular cavity 320, and the third hydrogen supply annular cavity 330 are respectively connected to a hydrogen source through a first hydrogen supply channel 311, a second hydrogen supply channel 321, and a third hydrogen supply channel 331, thereby forming hydrogen fuel supply channels for each stage of the combustion structure. For example, at the outlet of each annular cavity, a solenoid valve (not shown in the figure) controlled by a PLC (Programmable Logic Controller) is provided on each hydrogen fuel supply channel. By controlling the opening of the solenoid valves on each hydrogen fuel supply channel, independent hydrogen fuel supply is achieved for each stage of the independent combustion structure in each combustion unit.

[0048] In this embodiment of the invention, each level of the independent combustion structure of the above-mentioned combustion unit integrates a dot matrix cell structure and a TPMS cell structure.

[0049] Before entering the cellular structure, hydrogen gas first enters the hydrogen fuel tank, such as... Figures 1-6 As shown, in the main combustion unit 200, hydrogen first enters the first-stage main combustion hydrogen fuel chamber 212 in the first-stage main combustion structure 210, the second-stage main combustion hydrogen fuel chamber 222 in the second-stage main combustion structure 220, and the third-stage main combustion hydrogen fuel chamber 232 in the third-stage main combustion structure 230; in the shift combustion unit 100, hydrogen first enters the first-stage shift hydrogen fuel chamber 112 in the first-stage shift combustion structure 110, the second-stage shift hydrogen fuel chamber 122 in the second-stage shift combustion structure 120, and the third-stage shift hydrogen fuel chamber 132 in the third-stage shift combustion structure 130. The hydrogen fuel chamber consists of two layers of baffles with densely packed circular holes; for example, the baffles are plate-shaped or arc-shaped. The function of the hydrogen fuel chamber is to uniformly distribute the velocity and pressure of the incoming hydrogen, eliminate turbulence, and provide stable and uniform inlet conditions for subsequent premixing or stabilization processes.

[0050] After the hydrogen gas is stabilized, it enters the lattice cell structure. The lattice cell structure is selected from at least one of the Octet, Diamond, and IsoTruss structures. These structures are composed of a series of highly porous and three-dimensionally interconnected repeating lattice units. For example, the lattice cell structure is an Octet structure.

[0051] To accommodate the geometry of each stage, the lattice cell structures in the first stage are distributed in a cylindrical shape, such as the first-stage main combustion stage lattice cell structure 213 in the first-stage main combustion stage combustion structure 210 and the first-stage duty class lattice cell structure 113 in the first-stage duty class combustion structure 110; the lattice cell structures in the second and third stages are distributed in a cylindrical shell shape, such as the second-stage main combustion stage lattice cell structure 223 in the second-stage main combustion stage combustion structure 220, the second-stage duty class lattice cell structure 123 in the second-stage duty class combustion structure 120, the third-stage main combustion stage lattice cell structure 233 in the third-stage main combustion stage combustion structure 230, and the third-stage duty class lattice cell structure 133 in the third-stage duty class combustion structure 130.

[0052] Each stage of the combustion structure in the main combustion unit 200 and the lattice cell structures in the second and third stages of the duty combustion unit 100 have openings on their walls for introducing external air. Preferably, multiple openings are formed on the outer wall of the front end of the lattice cell structures in these stages, such as the first-stage main combustion stage opening 214 on the outer wall of the front end of the first-stage main combustion stage lattice cell structure 213, the second-stage main combustion stage opening 224 on the outer wall of the front end of the second-stage main combustion stage lattice cell structure 223, the third-stage main combustion stage opening 234 on the outer wall of the front end of the third-stage main combustion stage lattice cell structure 233, the second-stage duty lattice opening 124 on the outer wall of the front end of the second-stage duty lattice cell structure 123, and the third-stage duty lattice opening 134 on the outer wall of the front end of the third-stage duty lattice cell structure 133. These openings are key radial inlets for external air to enter and premix with hydrogen fuel. External air flows into the lattice cell structure through these open slots, where it is thoroughly and rapidly mixed with the axially flowing hydrogen fuel within the complex microscopic network of the lattice cell structure. Except for the open slots, the walls are completely closed, ensuring a controllable and efficient premixing process. This greatly promotes uniform mixing of hydrogen and air, effectively suppressing the formation of localized hydrogen-rich regions and high-temperature hotspots, thereby significantly reducing thermal NO₂ production. x The specific parameters of the opening slots are preferably as follows: the ratio of the radial height (H) to the wall thickness (T) of the slot, H / T, is 1.5:1 to 3:1; the ratio of the circumferential width (W) to the height (H) of the slot, W / H, is 1:1 to 2.5:1; the shape is rectangular, elliptical, or racetrack-shaped; it is uniformly distributed along the circumferential direction of the wall surface; in each lattice cell structure with opening slots, the area where all opening slots are located occupies 25% to 60% of the total area of ​​the outer wall surface at the front end of the lattice cell structure. This design ensures that air can effectively and deeply participate in mixing, while preventing hydrogen from prematurely escaping without mixing.

[0053] In the first-level duty lattice cell structure 113, there are no openings or slots on the wall. By utilizing the porous medium characteristics of the lattice cell structure, the hydrogen fuel is partially compressed and further stabilized, providing a stable and uniform hydrogen flow for subsequent diffusion combustion.

[0054] The gas (premixed hydrogen-air or pure hydrogen) pretreated by the aforementioned lattice cell structure then flows into the TPMS cell structure. The TPMS cell structure is a unique lattice structure with continuous three-dimensional curved surfaces, possessing extremely high specific surface area, high porosity, and unique multi-channel design. The TPMS cell structure can be selected from at least one of TPMS-Gyroid, TPMS-Lidinoid, and TPMS-Splitp structures; for example, the TPMS cell structure is selected as a Gyroid structure.

[0055] To accommodate the geometry of each stage, the TPMS cell structures in the first-stage combustion structure of all combustion units are distributed in a cylindrical shape, such as the first-stage main combustion stage TPMS cell structure 215 in the first-stage main combustion stage combustion structure 210 and the first-stage duty TPMS cell structure 114 in the first-stage duty combustion stage combustion structure 110; the TPMS cell structures in the second and third-stage combustion structures are distributed in a cylindrical shell shape, such as the second-stage main combustion stage TPMS cell structure 225 in the second-stage main combustion stage combustion structure 220, the second-stage duty TPMS cell structure 125 in the second-stage duty combustion stage combustion structure 120, the third-stage main combustion stage TPMS cell structure 235 in the third-stage main combustion stage combustion structure 230, and the third-stage duty TPMS cell structure 135 in the third-stage duty combustion stage combustion structure 130.

[0056] The aforementioned TPMS structure has two interconnected but separable channel networks. Fuel gas (premixed gas or hydrogen) flows stably axially towards the combustion outlet within one channel network. Simultaneously, cooling air flows radially into the other channel network from its outer wall. Its unique topological design ensures that the two fluid streams flow independently and do not mix.

[0057] When cooling air flows through the TPMS wall, which has a very large specific surface area, it can carry out efficient heat exchange, rapidly removing the heat generated by combustion, achieving powerful cooling of the nozzle structure, reducing the nozzle temperature, and further suppressing NO. x The generation of [something] extends nozzle life.

[0058] In addition, the complex network of tiny, tortuous, and continuous channels inside the TPMS creates a strong viscous resistance and quenching effect on flame propagation, which can effectively block the backfire of the flame and thus fundamentally suppress the backfire phenomenon, greatly improving the safety of the entire combustion system.

[0059] In embodiments of the present invention, such as Figures 3-7As shown, in the region where the lattice cell structure and the TPMS cell structure are combined, the air cooling channel is connected to the air chamber, that is, the first main combustion stage cooling channel is connected to the first main combustion stage air chamber 216, the first duty coolant cooling channel is connected to the first duty air chamber 115, the second main combustion stage cooling channel is connected to the second main combustion stage air chamber 226, the second duty coolant cooling channel is connected to the second duty air chamber 126, the third main combustion stage cooling channel is connected to the third main combustion stage air chamber 236, and the third duty coolant cooling channel is connected to the third duty air chamber 136. The walls of the first duty air chamber 115, the second duty air chamber 126, the third duty air chamber 136, the first main combustion stage air chamber 216, the second main combustion stage air chamber 226, and the third main combustion stage air chamber 236 are respectively provided with first duty air holes 116, second duty air holes 127, third duty air holes 137, first main combustion stage air holes 217, second main combustion stage air holes 227, and third main combustion stage air holes 237; each of the aforementioned air holes includes multiple small holes. External air flows into the air chambers through cylindrical shell-shaped cooling channels. After flowing through the air chambers outside the combustion structures of each stage, part of the cooling air enters the TPMS cell structure, while the other part flows out through the air holes. The outflowing air forms a cooling air curtain (isolation layer) between the combustion stages and between combustion units. This cooling airflow not only further enhances the structural cooling effect but also effectively isolates flames of different combustion stages, preventing mutual interference and crosstalk between flames. This ensures the independence, stability, and uniformity of combustion at each stage and prevents NOx emissions caused by flame crosstalk. x Emissions have increased in some areas.

[0060] In addition, multiple air ports are provided on the side of the entire nozzle head to introduce external air into the internal main air chamber 240. One end of the main air chamber 240 is supported by a reinforcing rib plate 241 to fix all combustion units and reduce vibration, preventing displacement and oscillation caused by thermal stress or vibration during combustion, and ensuring the overall strength, stability and operational reliability of the hydrogen fuel nozzle. The other end of the main air chamber 240 (i.e., the outlet end face of the entire hydrogen nozzle head) is designed with uniformly distributed cooling air holes 242. Cooling air flows out evenly through the air holes, forming comprehensive cooling of the entire hydrogen nozzle head, while further isolating the individual combustion units to prevent them from affecting each other during combustion, thereby ensuring the stability and uniformity of overall combustion.

[0061] This invention also provides a staged combustion control method for a hydrogen fuel nozzle based on the above-described multi-level cell structure, the method comprising:

[0062] Hydrogen fuel is supplied independently to each combustion unit of the hydrogen fuel nozzle through independent hydrogen fuel supply channels. Specifically, by controlling the opening and closing of solenoid valves installed in each hydrogen fuel supply channel via PLC, hydrogen fuel can be supplied independently to each individual combustion structure, achieving highly flexible combustion control.

[0063] Under low-load conditions: The PLC control only opens the solenoid valve on the hydrogen fuel supply channel leading to the first-stage combustion structure 110 of the duty combustion unit. Specifically, after the hydrogen gas undergoes pressure division and flow stabilization in this stage through the first-stage duty lattice cell structure 113, it flows through the first-stage duty TPMS cell structure 114 and flows out along the axial direction of the TPMS cell structure to the port. The cooled hydrogen gas is ejected and ignited to form a stable diffusion combustion flame, thereby forming a stable and highly interference-resistant high-temperature core zone. This flame serves as a reliable ignition source, ensuring combustion continuity under low-load conditions.

[0064] Under medium and high load conditions: Based on actual operating requirements, the PLC automatically calculates and independently opens the solenoid valves on the hydrogen fuel supply channels of each stage of the main combustion unit 200 and / or each stage of the duty combustion unit 100 according to power demand, to supply hydrogen fuel accordingly. Hydrogen gas is premixed with external air introduced from the opening slot in each stage of the main combustion unit 200 and the non-first stage combustion structure of the duty combustion unit 100 within the lattice cell structure. The resulting mixed gas is then ejected through the TPMS cell structure for efficient, low-NOx emission. x Premixed combustion. In this embodiment of the invention, under medium load conditions, the PLC controls the solenoid valves to independently open the hydrogen fuel supply channels of each stage of the main combustion unit and the second or third stage of the duty unit, according to actual operating requirements. Under high load conditions, all hydrogen fuel supply channels of each stage of the main combustion unit and the duty unit are fully opened, allowing the nozzles to operate at maximum power and provide maximum thrust or energy output. By independently controlling the opening of the solenoid valves in real time, optimal combustion efficiency and emission performance can be achieved. This intelligent combustion logic, combined with the aforementioned precise structural design, ensures that the nozzles can achieve efficient, stable, and low-emission combustion throughout the entire engine load range.

[0065] Throughout the process, a continuous flow of cooling air is introduced to the outside of the TPMS cell structure. This means that as the hydrogen fuel or mixed gas flows through the TPMS cell structure, cooling air is simultaneously introduced from the outside of the TPMS cell structure to create a synergistic cooling effect. By introducing cooling air from the outside of the TPMS cell structure, the TPMS cell structure achieves isolated flow between the premixed gas or hydrogen fuel and the cooling air, efficient cooling, and flashback suppression, ensuring that the cooling and flashback suppression functions remain effective at all times.

[0066] To verify the beneficial effects of the multi-stage cellular structure hydrogen fuel nozzle and its combustion control method described in this invention, numerical simulations of the hot combustion process were conducted. The simulation results directly demonstrate the effectiveness of this invention in suppressing backfire and reducing NO₂ levels. x Significant advantages in emissions and ensuring temperature field uniformity.

[0067] See Figure 8 The diagram illustrates the temperature distribution cloud map at the nozzle outlet when the hydrogen fuel combustion nozzle provided in this embodiment is operating in a hot state. Simulation results show that under stable combustion conditions, the nozzle outlet cross-sectional temperature is uniformly distributed within the range of 600 K to 800 K. This temperature is significantly lower than the flame temperature in the central region of the combustion chamber, and no localized high-temperature zones or backfire phenomena occur. This temperature distribution characteristic demonstrates that this invention achieves effective thermal management of the nozzle structure through the efficient cooling of the TPMS cell structure and the uniform premixing effect of the lattice cell structure, providing the necessary low-temperature environment to suppress backfire.

[0068] See Figure 9 It illustrates the NO at the nozzle outlet when the hydrogen fuel combustion nozzle provided in the embodiment of the present invention is operating in a hot state. X Emissions distribution cloud map. NO X Emissions increase exponentially with combustion temperature. NO x High emissions indicate the presence of localized high-temperature zones in the combustion chamber, poor temperature control, and excessive thermal NOx emissions. x High NO production; uneven fuel-air mixing easily generates localized "hot spots" and stoichiometric mixing regions (equivalent ratio close to 1), leading to high temperatures. Simulation results show that at the nozzle exit cross-section, NO... x Emissions are evenly distributed between 0 ppm and 2.28 ppm, with the highest NO emission level in the combustion chamber. x Emissions were also low (7.78 ppm). This indicates that the nozzle combustion temperature control was effective, avoiding localized high temperatures, while the hydrogen fuel and air were premixed evenly, resulting in a lower overall combustion temperature. These results confirm the advanced nozzle design, leading to a cleaner combustion process and a higher level of organization.

[0069] See Figure 10The diagram shows the distribution cloud map of hydroxyl (OH) radicals at the nozzle outlet under the same operating conditions. OH radicals are key reactive intermediates in the flame, and their concentration directly reflects the presence and location of the flame. Simulation results show that the concentration of OH radicals at the outlet cross-section of the nozzle of this invention is essentially zero. This indicates that the flame front is stably maintained outside the nozzle outlet, with no tendency to propagate back into the nozzle. This result directly confirms that the TPMS cell structure, with its complex microchannel characteristics, exerts a strong inhibitory effect on flame propagation, thereby completely eliminating backfire.

[0070] The simulation results above confirm that the hydrogen fuel nozzle structure described in this invention can simultaneously achieve efficient cooling, uniform temperature distribution, and low NO content. x Emissions and backfire suppression ensure the stability and safety of the hydrogen fuel combustion process.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-stage cellular structure hydrogen fuel nozzle, characterized in that, include: At least one center-value class combustion unit and multiple main combustion stage combustion units surrounding the center-value class combustion unit; Each of the combustion units includes a multi-stage independent combustion structure, which is wrapped from the inside out and forms an air cooling channel between adjacent stages and outside the outermost stage. Each of the independent combustion structures at each stage of the combustion unit integrates: a lattice cell structure and a TPMS cell structure; The lattice cell structure in each stage of the main combustion unit and in the non-first stage combustion structure of the duty combustion unit has an opening groove on its wall for introducing external air. The external air and hydrogen fuel are premixed and mixed in the lattice cell structure to form a premixed gas. The lattice cell structure in the first stage of the duty combustion unit does not have the opening groove on its wall. The hydrogen fuel or the premixed gas flowing out from the lattice cell structure flows to the TPMS cell structure and along its axial direction, and the walls of the TPMS cell structure are used for cooling air to flow through.

2. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, It also includes a multi-stage independent hydrogen fuel supply ring cavity, which is coaxially distributed with the hydrogen fuel nozzle, and is used to independently supply hydrogen fuel to different stages of combustion structures of the duty combustion unit and the main combustion unit.

3. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1 or 2, characterized in that, The duty combustion unit and the main combustion stage combustion unit are arranged in a ring array.

4. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, The multi-stage independent combustion structure is divided into three stages, from the inside out: a cylindrical first stage, a cylindrical shell-shaped second stage that surrounds the first stage, and a cylindrical shell-shaped third stage that surrounds the second stage; the air cooling channel is cylindrical shell-shaped.

5. The multi-stage cellular structure hydrogen fuel nozzle according to claim 4, characterized in that, The lattice cell structure and the TPMS cell structure are distributed in a cylindrical shape in the first stage of the combustion unit, and in a cylindrical shell shape in the second and third stages of the combustion unit.

6. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, Each combustion unit has a hydrogen fuel chamber at each stage hydrogen fuel inlet, which consists of two layers of perforated partitions.

7. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, The air cooling channel is connected to the air chamber, and air holes are provided on the wall of the air chamber.

8. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, The lattice cell structure is selected from at least one of Octet, Diamond, and IsoTruss structures; the TPMS cell structure is selected from at least one of TPMS-Gyroid, TPMS-Lidinoid, and TPMS-Splitp structures.

9. The multi-stage cellular structure hydrogen fuel nozzle according to claim 1, characterized in that, The opening slot is formed on the outer front wall of the lattice cell structure, and the area where the opening slot is formed accounts for 25% to 60% of the total area of ​​the outer front wall of the lattice cell structure.

10. A staged combustion control method, characterized in that, The method comprises: using a multi-stage cellular structure hydrogen fuel nozzle as described in any one of claims 1-9 Hydrogen fuel is supplied independently to each combustion unit of the hydrogen fuel nozzle through an independent hydrogen fuel supply channel. Under low load conditions, only the hydrogen fuel supply channel of the first stage combustion structure of the duty combustion unit is opened, so that the hydrogen fuel is pressure divided and stabilized through the lattice cell structure, and then ignited through the axial outlet port of the TPMS cell structure to form a diffusion combustion flame. Under medium and high load conditions, the hydrogen fuel supply channels of each stage of the combustion structure of the main combustion stage unit and the combustion structure of each stage of the duty combustion unit are opened according to the working conditions. In each stage of the combustion structure of the main combustion unit and the non-first stage combustion structure of the duty combustion unit, hydrogen fuel is premixed with external air introduced from the opening slot in the lattice cell structure to form a mixed gas, which then flows out through the TPMS cell structure for premixed combustion. As the hydrogen fuel or the mixed gas flows through the TPMS cell structure, a cooling airflow is introduced from the outside of the TPMS cell structure to create a synergistic cooling effect.

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