Three-dimensional numerical simulation method and system for hydrogen-doped combustion chamber of gas turbine, computer equipment and storage medium

Abstract

The invention discloses a three-dimensional numerical simulation method and system for a hydrogen-doped combustion chamber of a gas turbine, computer equipment and a storage medium, and relates to the technical field of gas turbines.The method comprises the steps that three-dimensional modeling is conducted on the basis of a to-be-simulated combustion chamber of the gas turbine, and a three-dimensional solid model of the combustion chamber is constructed; performing flow field mesh generation on the combustion chamber solid model by using a mesh generation tool to obtain a solid model with a flow field mesh; based on the solid model with the flow field grid, determining boundary conditions, selecting a proper chemical reaction mechanism and a turbulent combustion model, constructing a simulation numerical model, and performing calculation; according to the method, key parameters in the combustion process of the hydrogen combustion chamber can be rapidly and accurately obtained, the combustion state can be more visually mastered, calculation examples of different working conditions are calculated and analyzed and compared, the influence of the hydrogen mixing proportion on the combustion state of the combustion chamber and the pollutant emission condition can be obtained, and the method is suitable for popularization and application. And a calculation result has an important reference effect on practical engineering application.

Description

Technical Field

[0001] The present invention relates to the technical field of gas turbines, and in particular to a three-dimensional numerical simulation method, system, computer equipment and storage medium for a hydrogen-blended combustion chamber of a gas turbine. Background Art

[0002] The future development of gas turbines is spurred by the use of hydrogen. Traditional gas turbines use natural gas as their primary fuel. The addition of hydrogen significantly alters the chemical reaction kinetics of the fuel mixture, impacting key combustion parameters such as temperature, combustion stability, and emissions. Measuring combustion chamber parameters using hydrogen-blended combustion tests on gas turbines requires constant adjustment of the fuel's hydrogen content and extensive combustion testing. This is costly, time-consuming, and dangerous when the hydrogen content is too high. Therefore, three-dimensional numerical simulation methods for hydrogen-blended combustion in gas turbines hold broad potential for application.

[0003] In early 3D simulations of gas turbine combustors, engineers constructed mathematical models based on prior design experience and theoretical formulas. For example, based on the laws of thermodynamics and fluid mechanics, they derived the combustion and flow equations within the combustor. These equations were then used to perform preliminary simulations using numerical calculation software (such as early versions of Fluent). When determining boundary conditions, simplifying assumptions were often made. For example, the temperature, pressure, and flow rate at the combustor inlet and outlet were assumed to be uniformly distributed, ignoring the local variations that may occur during actual operation. To reduce computational complexity and time costs, some existing technologies significantly simplified the combustor's physical structure. For example, complex burner and flame tube structures were simplified into regular geometric shapes, such as cylinders or rectangular parallelepipeds. When addressing the chemical reactions of the fuel, simple single-step reaction models were used, considering only the primary reactants and products while ignoring intermediate products and complex reaction pathways. This approach can rapidly generate simulation results to a certain extent, but it sacrifices accuracy. Some researchers instead conduct local experiments to obtain key parameters and then apply these parameters to the 3D simulation. For example, combustion experiments are conducted in a laboratory setting on a localized area of ​​a combustor to measure parameters such as temperature, pressure, and flow rate. This experimental data is then input into the simulation model as boundary conditions or empirical coefficients. However, because experimental conditions differ from the operating conditions of an actual gas turbine combustor, these parameters can introduce significant errors when applied to the overall simulation. Summary of the Invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is: how to overcome the defects of traditional gas turbine hydrogen-blended combustion tests, which are high cost, time-consuming and dangerous when the hydrogen content is too high, and obtain combustion chamber related parameters through three-dimensional numerical simulation methods to better study the hydrogen-blended combustion process of gas turbines.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention provides a three-dimensional numerical simulation method for a hydrogen-doped combustion chamber of a gas turbine, comprising:

[0008] Perform three-dimensional modeling based on the gas turbine combustion chamber to be simulated and build a three-dimensional solid model of the combustion chamber;

[0009] Use meshing tools to perform flow field meshing on the combustion chamber solid model to obtain a solid model with flow field meshes;

[0010] Based on the solid model with flow field grid, the boundary conditions are determined, the appropriate chemical reaction mechanism and turbulent combustion model are selected, and the simulation numerical model is constructed and calculated.

[0011] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0012] The three-dimensional modeling of the combustion chamber of the gas turbine to be simulated to construct a three-dimensional solid model of the combustion chamber includes:

[0013] The geometric dimensions of each combustion chamber component are obtained, and each component is three-dimensionally modeled using drawing software. The components are assembled to form a combustion chamber solid model. In the process of constructing the three-dimensional solid model of the combustion chamber, the installation method between the combustion chamber components and the flow routes of air and fuel are analyzed, and local complex structures that do not affect the flow field characteristics and combustion state of the combustion chamber are simplified.

[0014] The beneficial effects of this preferred technical solution are: combining reverse mapping with CAD software to construct a solid model of the combustion chamber, simplifying local complex structures that do not affect the flow field characteristics and combustion state of the combustion chamber, which can improve modeling efficiency and avoid wasting too much time and computing resources on non-critical structures.

[0015] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0016] The three-dimensional modeling based on the gas turbine combustion chamber to be simulated to construct a three-dimensional solid model of the combustion chamber further includes:

[0017] The entire combustion chamber shape is used as the calculation area; based on the calculation consumption and computing hardware conditions, the specific calculation object is clarified, and the entrance of the calculation area is designated as the compressor outlet, and the exit is the end of the combustion chamber tail pipe.

[0018] The beneficial effects of this preferred technical solution are: considering the uncertainty of air distribution, reasonably determining the calculation area and inlet and outlet, and allocating the total air volume, providing a basis for accurate calculation, making the simulation more in line with actual conditions, and improving the accuracy of the calculation.

[0019] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0020] The method of using a meshing tool to perform flow field meshing on the combustion chamber solid model to obtain a solid model with a flow field mesh includes:

[0021] A meshing tool is used to divide the flow field of the combustion chamber solid model into mesh elements suitable for finite volume method calculations. The mesh elements include unstructured tetrahedral elements and structured hexahedral elements. The mesh type is selected based on the geometric shape of the solid model and the calculation requirements.

[0022] The beneficial effects of this preferred technical solution are: flexible selection of structured and unstructured grids based on the model shape and calculation requirements can better adapt to the complex geometric shape of the combustion chamber, while ensuring calculation accuracy and improving calculation efficiency.

[0023] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0024] The method of using a meshing tool to perform flow field meshing on the combustion chamber solid model to obtain a solid model with a flow field mesh further includes:

[0025] During the division process, different processing methods are adopted for different components. Unstructured grids are used for key components, and structured grids are used for regular components.

[0026] For walls that do not affect the global flow and whose temperature gradient in the thickness direction can be ignored, a zero wall thickness assumption is adopted to reduce the number of grids.

[0027] After the meshing is completed, the mesh units are quality checked to ensure that they are of qualified quality.

[0028] The beneficial effects of this preferred technical solution are: using different partitioning strategies and processing methods for different components, while ensuring accuracy and improving computational efficiency. Mesh quality checks ensure that subsequent calculations are accurate and avoid deviations in calculation results due to mesh quality issues.

[0029] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0030] The method of determining boundary conditions, selecting appropriate chemical reaction mechanisms and turbulent combustion models, building a simulation numerical model, and performing calculations based on a solid model with a flow field grid includes:

[0031] Based on the solid model with flow field grid and the design parameters or operating parameters of the gas turbine, the combustion chamber inlet and outlet boundary parameter values ​​are determined; the fuel calorific value under different blending ratios is calculated according to the fuel distribution amount and hydrogen blending ratio, and the fuel mass flow distribution of each nozzle is determined.

[0032] The beneficial effects of this preferred technical solution are: the inlet and outlet boundary parameters can be determined according to the design or operating parameters, the fuel calorific value and the flow rate of each nozzle can be calculated according to the fuel distribution and hydrogen blending ratio, the combustion process can be accurately simulated, and the simulation results can be closer to the actual combustion situation.

[0033] As a preferred solution for the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine, the following is presented:

[0034] The aforementioned steps of determining boundary conditions, selecting appropriate chemical reaction mechanisms and turbulent combustion models, constructing simulation numerical models, and performing calculations based on a solid model with a flow field grid also include:

[0035] When the design parameters of the gas turbine cannot be obtained, the monitoring points are found from the operating parameters, the compressor outlet parameters are used as the combustion chamber inlet conditions, and the turbine inlet temperature is used as the combustion chamber outlet temperature. The inlet and outlet boundary parameter values ​​are determined based on the three-dimensional data corresponding to the monitoring points; the actual temperature and pressure values ​​at the corresponding positions are obtained through sensors at the compressor outlet and turbine inlet of the gas turbine, and are used as the boundary conditions of the combustion chamber.

[0036] The beneficial effects of this preferred technical solution are: when design parameters are missing, the boundary conditions can be set through monitoring points and sensor measured values, ensuring the applicability and flexibility of the simulation method, and effective simulation calculations can be performed even when data is limited.

[0037] In a second aspect, an embodiment of the present invention provides a three-dimensional numerical simulation system for a gas turbine hydrogen-doped combustion chamber, comprising:

[0038] A three-dimensional solid model building module is used to perform three-dimensional modeling based on the gas turbine combustion chamber to be simulated and build a three-dimensional solid model of the combustion chamber;

[0039] A meshing module is used to perform flow field meshing on the combustion chamber solid model using a meshing tool to obtain a solid model with a flow field mesh;

[0040] The simulation module is used to determine boundary conditions, select appropriate chemical reaction mechanisms and turbulent combustion models, build simulation numerical models and perform calculations based on a solid model with a flow field grid.

[0041] In a third aspect, an embodiment of the present invention provides a computer device, including:

[0042] memory and processor;

[0043] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the one or more programs are executed by the one or more processors, the one or more processors implement the three-dimensional numerical simulation method of the hydrogen-blended combustion chamber of a gas turbine as described in any embodiment of the present invention.

[0044] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the three-dimensional numerical simulation method of the hydrogen-doped combustion chamber of a gas turbine.

[0045] The beneficial effects of the present invention are as follows: The present invention combines reverse mapping with CAD software to construct a solid model of the combustion chamber, simplifying non-critical structures and improving modeling efficiency. Taking into account the uncertainty of air distribution, the calculation area and inlet and outlet are reasonably determined, and the total air volume is allocated, providing a basis for accurate calculations. Based on the model shape and calculation requirements, structured and unstructured grids are flexibly selected, and different partitioning strategies and processing methods are adopted for different components, such as the zero wall thickness assumption, to ensure accuracy while improving calculation efficiency. Grid quality inspection ensures the accuracy of subsequent calculations. The inlet and outlet boundary parameters can be determined based on design or operating parameters. When design parameters are missing, they can be set through monitoring points and sensor measurements. The fuel calorific value and the flow rate of each nozzle are calculated based on the fuel distribution and hydrogen blending ratio to accurately simulate the combustion process. Various turbulent combustion models and chemical reaction mechanisms are verified using experimental equipment, and the optimal one is selected after comparison with experimental data to more realistically reflect the combustion flow conditions in the combustion chamber and improve simulation accuracy. After completing the preliminary preparations, numerical calculations are performed to obtain key data such as the temperature field of the combustion area of ​​the combustion chamber, the outlet temperature, and the emission conditions, providing strong support for combustion chamber design optimization, performance evaluation, and pollution control. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0047] Figure 1It is an overall flow chart of the three-dimensional numerical simulation method of the hydrogen-blended combustion chamber of a gas turbine according to the present invention;

[0048] Figure 2 It is a three-dimensional modeling diagram of the entire combustion chamber in a simulation example of the three-dimensional numerical simulation method of the gas turbine hydrogen-blended combustion chamber according to the present invention;

[0049] Figure 3 It is a schematic diagram of the entire calculation area in a simulation example of the three-dimensional numerical simulation method of the gas turbine hydrogen-doped combustion chamber according to the present invention;

[0050] Figure 4 It is a schematic diagram of the main burner grid in a simulation example of the three-dimensional numerical simulation method of the gas turbine hydrogen-doped combustion chamber according to the present invention;

[0051] Figure 5 It is a grid diagram of a central duty burner in a simulation example of a three-dimensional numerical simulation method of a gas turbine hydrogen-doped combustion chamber according to the present invention;

[0052] Figure 6 1. It is a schematic diagram of a calculation grid of a combustion chamber head in a simulation example of a three-dimensional numerical simulation method of a gas turbine hydrogen-doped combustion chamber according to the present invention;

[0053] Figure 7 1. It is a schematic diagram of a calculation grid of a tail cylinder in a simulation example of a three-dimensional numerical simulation method of a gas turbine hydrogen-doped combustion chamber according to the present invention;

[0054] Figure 8 1. It is a schematic diagram of the calculation grid of the annular cavity in the simulation example of the three-dimensional numerical simulation method of the gas turbine hydrogen-doped combustion chamber according to the present invention;

[0055] Figure 9 It is a schematic diagram of the grid of the combustion chamber calculation area in the simulation example of the three-dimensional numerical simulation method of the gas turbine hydrogen-blended combustion chamber described in the present invention. DETAILED DESCRIPTION

[0056] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, the following detailed description of the specific embodiments of the present invention is given in conjunction with the accompanying drawings. It is obvious that the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in this field without creative work should fall within the scope of protection of the present invention.

[0057] Example 1, with reference to Figure 1 , which is the first embodiment of the present invention, provides a three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber, comprising:

[0058] S1: Perform 3D modeling based on the gas turbine combustion chamber to be simulated and construct a 3D solid model of the combustion chamber;

[0059] S2: Use a meshing tool to perform flow field meshing on the combustion chamber solid model to obtain a solid model with a flow field mesh;

[0060] S3: Based on the solid model with the flow field grid, determine the boundary conditions, select the appropriate chemical reaction mechanism and turbulent combustion model, build a simulation numerical model and perform calculations.

[0061] It should be noted that steps S1-S3 sequentially complete the steps of constructing a solid model based on the combustion chamber to be simulated, meshing the flow field using meshing tools, determining boundary conditions based on the solid model with the flow field mesh, selecting an appropriate chemical reaction mechanism and turbulent combustion model, and constructing a simulation numerical model for calculation. This effectively and accurately simulates the combustion process in a gas turbine hydrogen-doped combustor. This provides a deeper understanding of the flow field characteristics, combustion state, and pollutant emissions within the combustor, providing a scientific and reliable basis for optimizing the design, improving performance, and reducing pollutant emissions of hydrogen-doped combustors in gas turbines. This has important practical application value and theoretical guidance for promoting the development of hydrogen-doped combustion technology for gas turbines.

[0062] Example 2, reference Figure 1 , which is an embodiment of the present invention, provides a three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber based on the previous embodiment, including:

[0063] In this embodiment, the three-dimensional modeling of the combustion chamber of the gas turbine to be simulated in step S1 is performed to construct a three-dimensional solid model of the combustion chamber, including:

[0064] Obtain geometric dimensions based on gas turbine design drawings or reverse mapping, build a combustion chamber solid model, and determine the calculation area.

[0065] Based on the geometric dimensions of each component, CAD software (such as ProE) is used to perform three-dimensional modeling on each component of the combustion chamber (burner head, fuel nozzle, flame tube and tail tube, etc.), and then the components are assembled to form a combustion chamber solid model.

[0066] During the modeling process, the installation methods between combustion chamber components and the flow routes of air and fuel are analyzed to find the main structures that affect the flow field characteristics and combustion state of the combustion chamber, and simplify the local complex structures that do not affect these characteristics.

[0067] Considering the uncertainty of the flow distribution of the total air volume in various parts of the combustion chamber, the entire combustion chamber shape is used as the calculation area. At the same time, the specific calculation object is determined based on the calculation consumption and computing hardware conditions. The inlet of the calculation area is designated as the compressor outlet, and the outlet is designated as the end of the combustion chamber tail pipe.

[0068] It should be noted that since the design drawings only give the total air volume at the combustion chamber inlet, in order to make the calculation more accurate, the entire combustion chamber is used as the calculation area, and the total air volume is divided into the oxygen part for combustion and the cooling air part for cooling.

[0069] In another possible implementation, virtual measurement technology can be used to create 3D models of the gas turbine combustor to be simulated. For example, a high-precision industrial photogrammetry system can be used to photograph the combustor from multiple angles. Software then processes and analyzes the captured images to reconstruct the combustor's 3D shape. This technology, without requiring direct contact with the object, can quickly acquire geometric information about complex shapes and is particularly suitable for large gas turbine combustors or those installed in specialized environments.

[0070] In another possible implementation, when performing 3D modeling of the gas turbine combustor to be simulated, CFD pre-simulation results can be incorporated. A simple CFD (computational fluid dynamics) pre-simulation can be performed to analyze the impact of different structural parameters on the combustor flow field and combustion performance. Based on the pre-simulation results, some of the combustor's structural components can be optimized and adjusted before 3D modeling is performed. For example, if the pre-simulation reveals that the flow rate in a certain area of ​​the flame tube is too low, resulting in incomplete combustion, the shape or size of that area can be modified during modeling to improve combustion.

[0071] In this embodiment, the meshing tool is used in step S2 to perform flow field meshing on the combustion chamber entity model. Obtaining the entity model with the flow field mesh includes:

[0072] Use meshing tools (such as Fluent, Gridgen, etc.) to divide the flow field of the combustion chamber solid model into mesh units suitable for finite volume method calculations.

[0073] The divided mesh units can be unstructured tetrahedral units or structured hexahedral units, etc.

[0074] It should be noted that structured meshes are suitable for regularly shaped graphics, offering fast generation speed and high mesh quality. However, when the geometry of a graphic is complex and irregular, the more flexible unstructured mesh is required. This can accommodate meshes of arbitrary shapes and connected regions, but the drawback is that it requires more memory and increases computation time. Therefore, the choice between these two meshes should be determined based on the geometry of the solid model and the computational requirements.

[0075] During the division process, different treatment methods are adopted for different components. The burner head, including the main burner and the central duty burner, as key components of the combustion chamber of the gas turbine, adopts unstructured meshes, while the tail pipe and the annular cavity can adopt structured meshes. For example, for walls that have no significant heat conduction effect, the temperature gradient in the thickness direction can be ignored, and they only serve as flow boundaries and do not need to consider structural deformation or stress and have no effect on the global flow, a zero wall thickness assumption can be adopted. For example, all the channel walls of the burner and the combustion chamber shell adopt the infinitely thin wall assumption of zero wall thickness to reduce the number of meshes. After the mesh division is completed, the mesh units are quality checked to ensure that the mesh units are of qualified quality to ensure the accuracy of subsequent numerical calculations.

[0076] It should be noted that during the meshing process, fine meshing of the entire burner solid model can significantly reduce computational efficiency. Therefore, different meshing strategies can be used for different components to improve computational efficiency while ensuring accuracy. After meshing, the mesh units are quality-checked to ensure that they meet quality standards, thereby ensuring the accuracy of subsequent numerical calculations.

[0077] In another possible implementation, when using a meshing tool to mesh the flow field, adaptive meshing techniques can be employed during the meshing process. Initial meshing is performed on the combustion chamber model, followed by preliminary numerical calculations. Based on the calculation results, the mesh is refined in areas where physical quantities vary dramatically (such as the flame front and high-gradient temperature zones), while areas with more gradual changes in physical quantities maintain the original mesh density or appropriately thin out the mesh. This reduces unnecessary mesh count while ensuring computational accuracy, thereby improving computational efficiency.

[0078] In another possible implementation, in addition to using structured or unstructured grids independently, a hybrid meshing approach can be employed. Structured grids are used for sections of the combustor with regular shapes and relatively simple flow (such as the majority of the tailpipe), while unstructured grids are used for sections with complex structures and highly variable flow characteristics (such as the junction between the burner head and the flame tube). The two different types of grids are then connected using specialized mesh interface technology to achieve meshing of the entire combustor flow field.

[0079] In this embodiment, the above step S3 includes determining boundary conditions based on a solid model with a flow field grid, selecting a suitable chemical reaction mechanism and turbulent combustion model, constructing a simulation numerical model, and performing calculations, including:

[0080] Based on a solid model with a flow field mesh and the design parameters of the gas turbine (such as air flow, inlet air temperature, fuel temperature, inlet air pressure, combustion pressure, etc.) or operating parameters, the parameter values ​​corresponding to the inlet and outlet boundary parameters of the combustion chamber are determined.

[0081] When the design parameters cannot be obtained, the monitoring points are found from the operating parameters, the compressor outlet parameters are used as the combustion chamber inlet conditions, and the turbine inlet temperature is used as the combustion chamber outlet temperature. The inlet and outlet boundary parameter values ​​are determined based on the three-dimensional data corresponding to the monitoring points; the actual temperature and pressure values ​​at the location are obtained through sensors at the compressor outlet and turbine inlet of the gas turbine, and are used as the boundary conditions of the combustion chamber.

[0082] The calorific value of the fuel at different blending ratios is calculated based on the fuel distribution amount and the hydrogen blending ratio to be studied, and the fuel mass flow distribution of each nozzle is determined.

[0083] Furthermore, in order to more realistically reflect the combustion flow conditions in the combustion chamber, reliability verification is carried out by selecting experimental equipment, and the temperature field, velocity field, reactants, intermediate products and pollutant emissions of various different turbulent combustion models and chemical reaction mechanisms are calculated respectively. The results are compared with the existing experimental data, and the fitting results are analyzed. Finally, the most appropriate turbulent combustion model (such as the FGM model) and chemical reaction mechanism (such as the GRI3.0 mechanism) are selected.

[0084] It should be noted that the experimental device was modeled, and different chemical reaction mechanisms and turbulence models were used on the model to carry out methane-hydrogen combustion. The experimental data of the experiment were compared and fitted with the numerical simulation results calculated by different mechanisms and models. A good fitting result proves that the chemical reaction mechanism and turbulence model are suitable for simulating hydrogen-mixed combustion in gas turbines, and the calculation accuracy is high.

[0085] Specifically, the steps for selecting an appropriate turbulent combustion model and chemical reaction mechanism include:

[0086] The Sydney Blunt Body Flame (HM1e) experimental setup was selected for reliability verification. Because the test fuel is methane mixed with hydrogen, it is an ideal configuration for evaluating methane-hydrogen combustion models. Based on this configuration, the temperature, velocity, reactant, intermediate product, and pollutant emissions fields for seven different turbulent combustion models and eight chemical reaction mechanisms were calculated. By comparing the internal flow field with existing experimental data and analyzing the fitting results, the most appropriate combustion model and chemical reaction mechanism were determined. The numerically calculated temperature, velocity (axial and radial) and composition fields at different axial positions were compared with experimental results. The composition field provides comparisons of the calculated concentrations of reactants (represented by H2 and O2), products (represented by H2O), intermediate products (represented by OH and CO), and the main pollutant (represented by NO).

[0087] For example, from the fitting results analysis of the calculation result curve and the experimental data curve, it can be found that the FGM model and the GRI3.0 mechanism have the best fitting effect with the experimental data.

[0088] After modeling and meshing the combustion chamber, determining the boundary conditions, and selecting the appropriate turbulence model and chemical reaction mechanism, numerical calculations are performed using simulation software to obtain results such as the temperature field in the combustion area of ​​the combustion chamber, the temperature of the combustion chamber outlet section, and the emission conditions at the outlet.

[0089] In another possible implementation, when determining boundary conditions and selecting appropriate chemical reaction mechanisms and turbulent combustion models for calculation, in addition to considering conventional fluid dynamics boundary conditions (such as air flow, pressure, etc.) and thermal boundary conditions (such as temperature), multi-field coupling boundary conditions can also be considered. For example, the thermal radiation boundary conditions of the combustion chamber wall can be considered, and the thermal radiation effect can be incorporated into the setting of boundary conditions by measuring or calculating parameters such as the emissivity and absorptivity of the wall. In addition, for some combustion chambers that use cooling technology, the mass, momentum, and energy exchange boundary conditions between the coolant and the main fluid can also be considered to make the setting of boundary conditions more in line with actual conditions.

[0090] Example 3. The above is a schematic scheme of the three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber according to this embodiment. It should be noted that the technical scheme of the three-dimensional numerical simulation system for a gas turbine hydrogen-doped combustion chamber and the technical scheme of the three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber described above are based on the same concept. For details not described in detail in the technical scheme of the three-dimensional numerical simulation system for a gas turbine hydrogen-doped combustion chamber according to this embodiment, please refer to the description of the technical scheme of the three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber described above.

[0091] This embodiment further provides a system based on a three-dimensional numerical simulation method of a gas turbine hydrogen-blended combustion chamber, comprising:

[0092] A three-dimensional solid model building module is used to perform three-dimensional modeling based on the gas turbine combustion chamber to be simulated and build a three-dimensional solid model of the combustion chamber;

[0093] A meshing module is used to perform flow field meshing on the combustion chamber solid model using a meshing tool to obtain a solid model with a flow field mesh;

[0094] The simulation module is used to determine boundary conditions, select appropriate chemical reaction mechanisms and turbulent combustion models, build simulation numerical models and perform calculations based on a solid model with a flow field grid.

[0095] This embodiment further provides a computer device applicable to a three-dimensional numerical simulation method for a hydrogen-doped combustion chamber of a gas turbine, comprising:

[0096] Memory and processor; the memory is used to store computer-executable instructions, and the processor is used to execute computer-executable instructions to implement the three-dimensional numerical simulation method of the hydrogen-blended combustion chamber of the gas turbine proposed in the above embodiment.

[0097] This embodiment further provides a storage medium storing a computer program, which, when executed by a processor, implements the three-dimensional numerical simulation method for a gas turbine hydrogen-doped combustion chamber as proposed in the above embodiment.

[0098] The storage medium proposed in this embodiment and the three-dimensional numerical simulation method of the gas turbine hydrogen-doped combustion chamber proposed in the above embodiment belong to the same inventive concept. For technical details not fully described in this embodiment, please refer to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0099] Example 4, with reference to Figure 2-Figure 9 Tables 1 and 2 are an embodiment of the present invention, which provides a three-dimensional numerical simulation method for a hydrogen-doped combustion chamber of a gas turbine. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through simulation experiments.

[0100] This simulation example studies an actual F-class heavy-duty gas turbine used for power generation and performs three-dimensional modeling of the combustion chamber.

[0101] The combustion system of the gas turbine under study features an annular tube combustion chamber structure, with the upper and lower combustion chamber casings integrally connected to the compressor and turbine outer casings. Twenty burners are inserted into the combustion chamber casing at an angle, evenly spaced along the circumference of the unit. The fuel nozzles consist of eight dry premixing main nozzles arranged in a circle, and a service nozzle located at the center of the circle.

[0102] In determining the calculation area, since the flow distribution of the total air volume in each part of the combustion chamber cannot be determined, the entire combustion chamber shape is considered as the calculation area, including the area formed by the combustion chamber shell and the outer cylinder. At the same time, considering the calculation consumption and calculation hardware conditions, one of the 20 burners (and the circumferential area of ​​18°) is taken as the calculation object. Figure 2 As shown in the figure, it is the three-dimensional modeling of the entire combustion chamber. The construction of the combustion chamber shape is carried out using the commercial CAD software ProE. The combustion chamber shape, including the burner head, fuel nozzle, flame tube and tail tube, is modeled separately and then assembled to provide shape detail information for mesh generation. Figure 3 As shown in Figure 1, it is a schematic diagram of the entire calculation area. Since the distribution of combustion air and cooling air in the combustion chamber is unknown, the inlet of the calculation area is specified to be the compressor outlet, and the outlet of the calculation area is specified to be the end of the combustion chamber tail pipe.

[0103] The meshing of a pre-built combustion chamber for a gas turbine was completed using the professional mesh generation software package Gridgen 15.15. The entire combustion chamber area from inlet to outlet was divided into 16 unstructured blocks, which were combined to form the entire combustion chamber fluid region. The total computational grid count was approximately 4.4 million, which met the accuracy requirements and computational cost requirements.

[0104] Figure 4 A schematic diagram of the mesh for the main burner is shown. The burner channel walls are assumed to be infinitely thin with zero thickness, avoiding the large mesh size required to resolve thin-walled structures. Furthermore, this thin-walled structure forms the boundary between computational blocks. The main burner comprises eight unstructured blocks within the computational domain.

[0105] Figure 5 A schematic diagram of the mesh for the central duty burner is given. Similarly, the burner channel wall is assumed to be infinitely thin with zero wall thickness, and the mesh is dense near the swirl vane channel. The central duty burner constitutes an unstructured block in the computational domain.

[0106] Figure 6 The computational mesh of the combustion chamber head is given. This part of the computational mesh includes the computational space of the burner head after removing the main swirler and the service swirler. The primary air inlet is arranged circumferentially at the rear, supplied by primary air jet holes.

[0107] Figure 7 The calculation grid for the tailpipe is presented. The first two rows of cooling air inlets are assumed to have equivalent areas. Each row has five cooling holes arranged circumferentially, with the area of ​​the holes being the same as the original. The last row (the third row) has the same size and arrangement as the original cooling holes.

[0108] Figure 8This is a schematic diagram of the calculation grid of the annular cavity. Since the flow details in the annular cavity are not of concern during the numerical simulation of hydrogen-blended combustion in the combustion chamber, the calculation of this part is only to ensure the flow distribution among the various parts of the combustion chamber. Therefore, in order to reduce the computational cost, the calculation grid of this part is sparse compared with other blocks. The local grid is encrypted near the corner points where the curvature changes greatly to ensure the convergence of the calculation.

[0109] Figure 9 A grid diagram of the entire combustion chamber calculation area is shown. The outer wall of the calculation area corresponds to the inner wall of the combustion chamber shell. Air enters from the left annular space. The flow space formed by the outer wall of the calculation area and the outer wall of the flame tube determines the air distribution in various parts of the combustion chamber. The inner walls of the flame tube and the tail tube form the combustion and mixing space. After combustion, the fuel is discharged from the end of the tail tube.

[0110] Step 3: Based on the physical model and the specific design conditions of the gas turbine, the boundary conditions of the combustion chamber inlet and outlet are analyzed and calculated, and the appropriate chemical reaction mechanism and turbulent combustion model are selected to construct a numerical model for combustion chamber flow field simulation.

[0111] In this example, the Sydney blunt-body flame HM1e experimental device was used for reliability verification. The temperature field, velocity field, reactants, intermediate products, and pollutant emissions of seven different turbulent combustion models and eight chemical reaction mechanisms were calculated. By comparing the existing experimental data with the internal flow field conditions and analyzing the fitting results, it was concluded that the most suitable turbulent combustion model and chemical reaction mechanism for calculating hydrogen-blended combustion in gas turbines are the FGM model and the GRI3.0 mechanism.

[0112] The known design conditions of the gas turbine are shown in Table 1.

[0113] Table 1 Design parameters of a certain type of gas turbine

[0114]

[0115]

[0116] Calculate the combustion chamber operating pressure:

[0117] p2=17×101325=1722525Pa

[0118] Compute the air inlet boundary conditions:

[0119] The total air volume is 651 kg / s, of which 83% is fed into the combustion chamber and 17% is used for cooling. There are 20 combustion chambers along the circumference, so the flow rate of each combustion chamber is G = 651 / 20 × 0.83 = 27 kg / s;

[0120] The isentropic adiabatic temperature at the compressor outlet (combustion chamber inlet) is:

[0121] T 2s =T1π k-1 / k =290×17 0.4 / 1.4 =652K

[0122] Actual temperature at compressor outlet (combustion chamber inlet):

[0123]

[0124] Fuel inlet boundary conditions:

[0125] Taking 100% natural gas (original conditions) as an example (natural gas is calculated as 100% pure CH4, Qlow = 50108 kJ / kg), the calculation method is as follows. The calculation results of fuels with different hydrogen blending ratios are shown in Table 2.

[0126] a) Main fuel inlet

[0127] Fuel requirement:

[0128]

[0129] Q f =0.0217×651=14.126kg / s

[0130] The fuel volume of the watch nozzle and the main fuel nozzle accounts for 15% and 85% of the total fuel volume respectively.

[0131]

[0132] b) Duty fuel inlet

[0133]

[0134] Maintaining constant unit output, constant unit specific power, constant compressor pressure ratio, and constant air flow, the above calculation method yields the required fuel volume and fuel flow rate for each fuel nozzle at different hydrogen blending ratios, as shown in the table. The calculation results in the table show that, while unit output remains constant, the fuel mass flow rate in the combustion chamber decreases as the hydrogen blending ratio increases.

[0135] Table 2 Calculation boundary conditions for different hydrogen mixing ratios in the combustion chamber

[0136]

[0137] With the aforementioned boundary conditions in place, numerical calculations can be performed using the selected chemical reaction mechanism and turbulent combustion model to obtain the desired temperature field in the combustion chamber's combustion area, the temperature of the combustion chamber's outlet cross-section, and the emissions at the outlet. This method allows for quick and accurate determination of key parameters in the hydrogen-fired combustion process, providing a more intuitive understanding of the combustion state. By performing calculations and comparative analysis on examples of different operating conditions, the impact of the hydrogen blending ratio on the combustion state and pollutant emissions in the combustion chamber can be determined. The results provide valuable insights for practical engineering applications.

[0138] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber, characterized in that: include: Perform three-dimensional modeling based on the gas turbine combustion chamber to be simulated and build a three-dimensional solid model of the combustion chamber; Use meshing tools to perform flow field meshing on the combustion chamber solid model to obtain a solid model with flow field meshes; Based on the solid model with flow field grid, the boundary conditions are determined, the appropriate chemical reaction mechanism and turbulent combustion model are selected, and the simulation numerical model is constructed and calculated.

2. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 1, characterized in that: The three-dimensional modeling of the combustion chamber of the gas turbine to be simulated to construct a three-dimensional solid model of the combustion chamber includes: The geometric dimensions of each combustion chamber component are obtained, and each component is three-dimensionally modeled using drawing software. The components are assembled to form a combustion chamber solid model. In the process of constructing the three-dimensional solid model of the combustion chamber, the installation method between the combustion chamber components and the flow routes of air and fuel are analyzed, and local complex structures that do not affect the flow field characteristics and combustion state of the combustion chamber are simplified.

3. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 2, characterized in that: The three-dimensional modeling based on the gas turbine combustion chamber to be simulated to construct a three-dimensional solid model of the combustion chamber further includes: The entire combustion chamber shape is used as the calculation area; based on the calculation consumption and computing hardware conditions, the specific calculation object is clarified, and the entrance of the calculation area is designated as the compressor outlet, and the exit is the end of the combustion chamber tail pipe.

4. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 3, characterized in that: The method of using a meshing tool to perform flow field meshing on the combustion chamber solid model to obtain a solid model with a flow field mesh includes: A meshing tool is used to divide the flow field of the combustion chamber solid model into mesh elements suitable for finite volume method calculations. The mesh elements include unstructured tetrahedral elements and structured hexahedral elements. The mesh type is selected based on the geometric shape of the solid model and the calculation requirements.

5. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 4, characterized in that: The method of using a meshing tool to perform flow field meshing on the combustion chamber solid model to obtain a solid model with a flow field mesh further includes: During the division process, different processing methods are adopted for different components. Unstructured grids are used for key components, and structured grids are used for regular components. For walls that do not affect the global flow and whose temperature gradient in the thickness direction can be ignored, a zero wall thickness assumption is adopted to reduce the number of grids. After the meshing is completed, the mesh units are quality checked to ensure that they are of qualified quality.

6. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 5, characterized in that: The method of determining boundary conditions, selecting appropriate chemical reaction mechanisms and turbulent combustion models, building a simulation numerical model, and performing calculations based on a solid model with a flow field grid includes: Based on the solid model with flow field grid and the design parameters or operating parameters of the gas turbine, the combustion chamber inlet and outlet boundary parameter values ​​are determined; the fuel calorific value under different blending ratios is calculated according to the fuel distribution amount and hydrogen blending ratio, and the fuel mass flow distribution of each nozzle is determined.

7. The three-dimensional numerical simulation method for a gas turbine hydrogen-blended combustion chamber according to claim 6, characterized in that: The aforementioned steps of determining boundary conditions, selecting appropriate chemical reaction mechanisms and turbulent combustion models, constructing simulation numerical models, and performing calculations based on a solid model with a flow field grid also include: When the design parameters of the gas turbine cannot be obtained, the monitoring points are found from the operating parameters, the compressor outlet parameters are used as the combustion chamber inlet conditions, and the turbine inlet temperature is used as the combustion chamber outlet temperature. The inlet and outlet boundary parameter values ​​are determined based on the three-dimensional data corresponding to the monitoring points; the actual temperature and pressure values ​​at the corresponding positions are obtained through sensors at the compressor outlet and turbine inlet of the gas turbine, and are used as the boundary conditions of the combustion chamber.

8. A three-dimensional numerical simulation system for a hydrogen-doped combustion chamber of a gas turbine, using the method according to any one of claims 1 to 7, characterized in that: include: A three-dimensional solid model building module is used to perform three-dimensional modeling based on the gas turbine combustion chamber to be simulated and build a three-dimensional solid model of the combustion chamber; A meshing module is used to perform flow field meshing on the combustion chamber solid model using a meshing tool to obtain a solid model with a flow field mesh; The simulation module is used to determine boundary conditions, select appropriate chemical reaction mechanisms and turbulent combustion models, build simulation numerical models and perform calculations based on a solid model with a flow field grid.

9. A computer device comprising: memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions, when executed by a processor, implement the steps of the method according to any one of claims 1 to 7.

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