Method and device for determining acoustic natural frequency of gas turbine combustor

Abstract

The present invention discloses a method and device for determining the acoustic natural frequency of a gas turbine combustion chamber. The method includes: performing flow field grid division on a pre-constructed combustion chamber solid model to obtain a first solid model with flow field grids, the model including a plurality of grid nodes; constructing a combustion chamber flow field simulation numerical model according to the first solid model, the parameter values corresponding to the pre-acquired combustion chamber inlet boundary parameters, the parameter values corresponding to the combustion chamber outlet boundary parameters, and the pre-configured constraint conditions; determining the temperature data corresponding to each of the grid nodes in the first solid model based on the combustion chamber flow field simulation numerical model; performing acoustic grid division on the combustion chamber solid model to obtain a second solid model with acoustic grids; constructing a combustion chamber acoustic numerical model based on the second solid model, the pre-acquired combustion chamber inlet boundary type, the combustion chamber outlet boundary type, and the temperature data of each grid node; and determining the acoustic natural frequency of the combustion chamber based on the combustion chamber acoustic numerical model.

Description

Technical Field

[0001] The present invention relates to the field of gas turbines, and particularly to a method and device for determining the acoustic natural frequency of a gas turbine combustor. Background Art

[0002] Gas turbines for power generation generally adopt lean-premixed staged combustion technology to control the generation of NOx pollutants by reducing the combustion temperature. However, lean-premixed combustion is relatively sensitive to changes in parameters such as fuel composition, air-fuel ratio, and atmospheric temperature, and is prone to thermoacoustic oscillation combustion instability problems. Combustion instability will generate complex sound pressure noise, and the acoustic natural frequency is an important basis for judging whether combustion noise will excite thermoacoustic coupled oscillation combustion. It is also a characteristic parameter of the combustor that needs to be focused on during the design process of the gas turbine combustor, and has an important guiding role in combustion state diagnosis and combustion stability control.

[0003] Currently, generally, the acoustic natural frequency of the combustor is measured mainly through a large number of combustion tests. It is necessary to open combustion pressure pulsation measurement holes on the combustor wall surface, and the test system and device are complex. Moreover, for heavy-duty gas turbines, the cost of combustion tests is high. Therefore, how to obtain the acoustic natural frequency of the combustor quickly, effectively, and conveniently is an urgent problem to be solved at present. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of high test cost and complex test device when measuring the acoustic natural frequency of a gas turbine combustor by using the test method in the prior art, so as to provide a method and device for determining the acoustic natural frequency of a gas turbine combustor.

[0005] In a first aspect, the present invention provides a method for determining the acoustic natural frequency of a gas turbine combustor, including: performing flow field grid division on a pre-constructed combustor solid model to obtain a first solid model carrying flow field grids, where the first solid model includes a plurality of grid nodes; constructing a combustor flow field simulation numerical model according to the first solid model, the parameter values corresponding to the pre-acquired combustor inlet boundary parameters and the parameter values corresponding to the combustor outlet boundary parameters, and the pre-configured constraint conditions; determining the temperature data corresponding to each grid node in the first solid model based on the combustor flow field simulation numerical model; performing acoustic grid division on the combustor solid model to obtain a second solid model carrying acoustic grids; constructing a combustor acoustic numerical model based on the second solid model, the pre-acquired combustor inlet boundary type, the combustor outlet boundary type, and the temperature data corresponding to each grid node; and determining the acoustic natural frequency based on the combustor acoustic numerical model.

[0006] The present invention divides the combustion chamber physical model into flow field grids, and based on the first physical model carrying the flow field grids, the parameter values corresponding to the combustion chamber inlet boundary parameters and the parameter values corresponding to the combustion chamber outlet boundary parameters obtained in advance, as well as the pre-configured constraint conditions, constructs a combustion chamber flow field simulation numerical model. After performing steady-state numerical calculations on the combustion chamber flow field simulation numerical model, the temperature data of each grid node corresponding to the flow field grids divided in the first physical model is output. The combustion chamber physical model is divided into acoustic grids. Based on the second physical model carrying the acoustic grids, the pre-determined combustion chamber inlet boundary type and outlet boundary type, as well as the temperature data of each grid node determined by the combustion chamber flow field simulation numerical model, a combustion chamber acoustic numerical model is constructed. When the combustion chamber acoustic numerical model is constructed, the constructed combustion chamber acoustic numerical model is used for calculation, and the same number of acoustic natural frequency values as the preset order are output, thereby obtaining the acoustic natural frequency of the gas turbine combustion chamber. This method determines the acoustic natural frequency of the combustion chamber through the constructed combustion chamber acoustic numerical model, without measuring the acoustic natural frequency of the combustion chamber through a large number of experiments, avoiding the defects of high test costs and complex test devices in the prior art. On the basis of ensuring low costs, this method can also quickly and conveniently obtain the acoustic natural frequency of the combustion chamber, ensuring the efficiency of the acquisition process.

[0007] Combined with the first aspect, in the first embodiment of the first aspect, after determining the acoustic natural frequency based on the combustion chamber acoustic numerical model, it further includes: determining a first curve based on the acoustic natural frequency and the first parameter value corresponding to the first inlet boundary parameter of the combustion chamber flow field simulation numerical model, where the first inlet boundary parameter is any one of the multiple inlet boundary parameters of the combustion chamber flow field simulation numerical model. The abscissa corresponding to the first curve is used to indicate the combustion moment, and the ordinate corresponding to the first curve is used to indicate the second parameter value corresponding to the first inlet boundary parameter corresponding to each combustion moment. After replacing the first parameter value corresponding to the first inlet boundary parameter in the combustion chamber flow field simulation numerical model with the second parameter value, transient numerical calculations are performed, and a calculation result is generated. A second curve is generated based on the calculation result. The acoustic natural frequency is verified based on the first curve and the second curve to determine the accuracy of the acoustic natural frequency.

[0008] After the acoustic natural frequency is output by the combustion chamber acoustic numerical model, according to the output acoustic natural frequency, the parameter value corresponding to the inlet boundary parameter of the combustion chamber flow field simulation numerical model is used to determine the first curve. And according to the first curve, at the corresponding combustion moment, the parameter value corresponding to the inlet boundary parameter of the combustion chamber flow field simulation numerical model is modified to the second parameter value corresponding in the first curve. Then, when the combustion chamber acoustic numerical model performs transient numerical calculation, it will adjust the corresponding first parameter value according to each combustion moment and generate calculation results corresponding to each combustion moment. According to the calculation results, the second curve is determined. Finally, based on the first curve and the second curve, the acoustic natural frequency output by the combustion chamber acoustic numerical model is verified to ensure the accuracy of the natural frequency output by the combustion chamber acoustic simulation model.

[0009] Combined with the first aspect, in the second embodiment of the first aspect, verifying the acoustic natural frequency based on the first curve and the second curve includes: performing Fourier transform on the first curve to obtain the third curve; performing Fourier transform on the second curve to obtain the fourth curve; verifying the acoustic natural frequency according to the third curve and the fourth curve.

[0010] The present invention converts the first curve into the third curve and the second curve into the fourth curve through Fourier transform. The first amplitude corresponding to the first acoustic natural frequency at the combustion chamber inlet can be read from the third curve, and the second amplitude corresponding to the first acoustic natural frequency inside the combustion chamber can be read from the fourth curve. Then, according to the judgment of the first amplitude and the second amplitude, when the parameter value corresponding to the combustion chamber inlet boundary parameter is modified, whether the amplitude corresponding to this parameter inside the combustion chamber is amplified or remains unchanged is used to verify the accuracy of the acoustic natural frequency.

[0011] Combined with the first aspect, in the third embodiment of the first aspect, the abscissa of the third curve is used to indicate the frequency of the combustion chamber inlet boundary perturbation excitation, and the ordinate is used to indicate the first amplitude corresponding to the first inlet boundary parameter at the combustion chamber inlet. The abscissa of the fourth curve is used to indicate the frequency corresponding to the first inlet boundary parameter inside the combustion chamber, and the ordinate is used to indicate the second amplitude corresponding to the first inlet boundary parameter inside the combustion chamber. Verifying the acoustic natural frequency based on the third curve and the fourth curve includes: obtaining the first amplitude corresponding to the first acoustic natural frequency from the third curve, where the first acoustic natural frequency is any one of multiple acoustic natural frequencies; obtaining the second amplitude corresponding to the first frequency from the fourth curve, where the first frequency is the frequency corresponding to any wave peak in the fourth curve and the first frequency is within the preset domain of the first acoustic natural frequency; judging the magnitudes of the first amplitude and the second amplitude. When the second amplitude is greater than the first amplitude, or when the second amplitude is less than the first amplitude and the difference between the first amplitude and the second amplitude is less than the preset threshold, it is determined that the first acoustic natural frequency is correct.

[0012] In the present invention, the first acoustic natural frequency and the first amplitude corresponding to the first acoustic natural frequency are obtained from the third curve, the second amplitude corresponding to the first acoustic natural frequency is obtained from the fourth curve, and the accuracy of the first acoustic natural frequency is verified by comparing the magnitude relationship between the first amplitude and the second amplitude. Since the setting conditions of the combustion chamber flow field simulation numerical model are all determined, the calculation results obtained by transient calculation through this model are also determined. Therefore, the data in the fourth curve after transformation based on this calculation result are also accurate. Thus, the accuracy of the natural frequency can be determined by comparing it with the second amplitude in the fourth curve.

[0013] Combined with the first aspect, in the fourth embodiment of the first aspect, determining the first curve based on the acoustic natural frequency and the first parameter value corresponding to the first inlet boundary parameter of the combustion chamber flow field simulation numerical model includes: generating a sub-function corresponding to each acoustic natural frequency based on all acoustic natural frequencies, the first inlet boundary value of the combustion chamber flow field simulation numerical model, and a preset phase; combining the sub-functions corresponding to all acoustic natural frequencies to generate an objective function; and generating the first curve based on the objective function.

[0014] The present invention generates an objective function based on the acoustic natural frequency, the parameter value of the first inlet parameter boundary of the combustion chamber flow field simulation numerical model, and a preset phase value, and generates a corresponding first curve based on the objective function. Thus, it is convenient to load the first curve graph to the first inlet parameter boundary of the combustion chamber flow field simulation numerical model, and a second curve is obtained through transient calculation by the combustion chamber flow field simulation numerical model, so as to verify the acoustic natural frequency through the first curve and the second curve.

[0015] Combined with the first aspect, in the fifth embodiment of the first aspect, the method further includes: determining the type of the combustion chamber inlet / outlet boundary based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameters of the combustion chamber inlet / outlet boundary.

[0016] Combined with the first aspect, in the sixth embodiment of the first aspect, determining the type of the combustion chamber inlet / outlet boundary based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameters of the combustion chamber inlet / outlet boundary includes: making a primary determination of the type of the combustion chamber inlet / outlet boundary based on the structural characteristics of the combustion chamber inlet / outlet boundary. When it is determined that the combustion chamber inlet / outlet type is a hard boundary, the determination process ends; or, when it is impossible to determine whether the combustion chamber inlet / outlet type is a hard boundary, a secondary determination of the type of the combustion chamber inlet / outlet boundary is made based on the airflow parameters of the combustion chamber inlet / outlet boundary, and the type of the combustion chamber inlet / outlet boundary is determined based on the result of the secondary determination.

[0017] The present invention determines the types of the inlet / outlet boundaries of the combustion chamber by analyzing the structural characteristics of the inlet / outlet boundaries of the combustion chamber and the airflow parameters of the inlet / outlet boundaries. Through this method, a preliminary judgment on the types of the inlet / outlet boundaries of the combustion chamber can be made more objectively and accurately. Since the types of the inlet / outlet boundaries of the combustion chamber are one of the conditions for constructing the acoustic numerical model of the combustion chamber, when the accuracy of the types of the inlet / outlet boundaries of the combustion chamber is improved, the accuracy of the natural frequencies output by the acoustic numerical model of the combustion chamber can also be ensured.

[0018] In a second aspect, the present invention provides an apparatus for determining the acoustic natural frequency of a gas turbine combustion chamber, including: a first partitioning module for partitioning the flow field grid of a pre-constructed combustion chamber solid model to obtain a first solid model with a flow field grid, where the first solid model includes a plurality of grid nodes; a first construction module for constructing a combustion chamber flow field simulation numerical model according to the first solid model, the pre-obtained combustion chamber inlet boundary value and combustion chamber outlet boundary value, and the pre-configured constraint conditions; an acquisition module for determining the temperature data corresponding to each grid node in the first solid model based on the combustion chamber flow field simulation numerical model; a second partitioning module for partitioning the acoustic grid of the combustion chamber solid model to obtain a second solid model with an acoustic grid; a second construction module for constructing an acoustic numerical model of the combustion chamber based on the second solid model, the pre-obtained combustion chamber inlet boundary type, combustion chamber outlet boundary type, and the temperature data corresponding to each grid node; and a first determination module for determining the acoustic natural frequency based on the acoustic numerical model of the combustion chamber.

[0019] In a third aspect, the present invention provides a computer device, including: a memory and a processor, which are communicatively connected to each other. The memory is used to store a computer program. When the computer program is executed by the processor, the processor executes the method for determining the acoustic natural frequency of a gas turbine combustion chamber according to any one of the invention contents.

[0020] In a fourth aspect, the present invention provides a computer-readable storage medium, which is used to store computer instructions. When the computer instructions are executed by the processor, the method for determining the acoustic natural frequency of a gas turbine combustion chamber according to any one of the invention contents is implemented. Description of the Drawings

[0021] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1Flow chart of the method for determining the acoustic natural frequency of a gas turbine combustor provided in an embodiment of the present invention;

[0023] Figure 2 Combustion chamber structure diagram provided in an embodiment of the present invention;

[0024] Figure 3 Time-domain diagram of the inlet pressure pulsation disturbance of the combustion chamber provided in an embodiment of the present invention;

[0025] Figure 4 Frequency-domain diagram of the inlet pressure pulsation disturbance of the combustion chamber provided in an embodiment of the present invention;

[0026] Figure 5 Time-domain diagram of the internal pressure pulsation disturbance of the combustion chamber provided in an embodiment of the present invention;

[0027] Figure 6 Frequency-domain diagram of the internal pressure pulsation disturbance of the combustion chamber provided in an embodiment of the present invention;

[0028] Figure 7 Connection diagram of the device for determining the acoustic natural frequency of a gas turbine combustor provided in an embodiment of the present invention;

[0029] Figure 8 Connection diagram of the computer device provided in an embodiment of the present invention. Detailed implementation manners

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] The present invention discloses a method for determining the acoustic natural frequency of a gas turbine combustor. As Figure 1 shown, the method specifically includes the following steps:

[0032] Step S1: Perform flow field grid division on a pre-constructed combustion chamber solid model to obtain a first solid model carrying flow field grids, and the first solid model includes a plurality of grid nodes.

[0033] Specifically, a meshing tool can be called to mesh the flow field grid of the combustion chamber solid model. When meshing, it needs to be meshed into grid cells suitable for finite volume method calculation, and the meshed combustion chamber solid model, that is, the first solid model with the flow field grid, is obtained. In this solid model, the nodes of the meshed grid cells are included. In this process, the meshing tool can use meshing software such as Fluent and Flotherm; the meshed grid cells can be unstructured tetrahedral cells or structured hexahedral cells, etc.

[0034] Specifically, after the grid meshing is completed, it is necessary to check the quality of the meshed grid cells. Generally, the standard for quality inspection is to judge whether the skewness value of the grid cell is higher than 0.95. When the skewness value is not higher than 0.95, it means that the grid cell quality is qualified. When the skewness value is higher than 0.95, it means that the grid cell quality is unqualified and the grid meshing needs to be redone.

[0035] In an implementable example, the combustion chamber structure diagram is as Figure 2 shown. By analyzing the combustion chamber structure characteristics and the air flow path, it is found that the air participating in combustion mainly enters from the combustion chamber inlet boundary 5 at the left end face of the fuel nozzle 1, and the fuel mainly sprays out from the fuel holes on the surface of the swirl vane 6. After the fuel and air are fully combusted in the flame tube 2 and the transition section 3, they then flow out from the combustion chamber outlet boundary 4 at the right end face of the transition section 3. Considering that the acoustic natural frequency of the combustion chamber is mainly related to the internal cavity structure of the combustion chamber, the small fuel injection holes in the swirl vane 6 can be ignored when establishing the combustion chamber acoustic model. Since there are no design drawings, the reverse mapping method is used to obtain the geometric dimensions of components such as the fuel nozzle 1, the flame tube 2, and the transition section 3, and the local small boss structures in the fuel nozzle 1, the flame tube 2, and the transition section 3 are simplified to establish the combustion chamber solid model.

[0036] Specifically, for the construction of the combustion chamber solid model, it is necessary to first analyze the installation method between the combustion chamber components and the flow routes of air and fuel to find out the main structures that affect the acoustic natural frequency and the flow field characteristics of the combustion chamber; then obtain the geometric dimensions of the combustion chamber components according to the design drawings of the combustion chamber components, and construct the combustion chamber solid model according to the geometric dimensions of the combustion chamber components. In this process, the local complex structures that do not affect the acoustic natural frequency and the flow field characteristics of the combustion chamber can be simplified; when there are no design drawings of the combustion chamber components, the geometric dimensions of the combustion chamber components can also be obtained by the reverse mapping method, and then the combustion chamber solid model is established according to the geometric dimensions.

[0037] Step S2: Construct a combustion chamber flow field simulation numerical model according to the first solid model, the parameter values corresponding to the pre-acquired combustion chamber inlet boundary parameters and the parameter values corresponding to the combustion chamber outlet boundary parameters, and the pre-configured constraint conditions.

[0038] Specifically, after dividing the combustion chamber flow field grid and obtaining the first solid model with the flow field grid, determine the parameter values corresponding to the combustion chamber inlet boundary parameters and the parameter values corresponding to the combustion chamber outlet boundary parameters through the design parameters of the gas turbine or the operating parameters of the gas turbine; and select one item each from the combustion model and the turbulence model as the constraint conditions for combustion calculation. For example, the Eddy Dissipation Concept model can be selected in the combustion model, and the k-ε model can be selected in the turbulence model.

[0039] Specifically, the inlet boundary parameters or outlet boundary parameters of the combustion chamber include three dimensions: mass flow rate, temperature, and pressure. The mass flow rate at the inlet includes the air mass flow rate and the fuel mass flow rate. The temperature at the inlet includes the air temperature and the fuel temperature. The pressure at the inlet includes the air pressure and the fuel pressure. When determining the inlet / outlet boundary conditions of the combustion chamber, when the design parameters of the gas turbine exist, the corresponding values of the above three dimensions can be directly obtained from the design parameters as the parameter values of the inlet boundary parameters or the outlet boundary parameters. When the design parameters of the gas turbine cannot be obtained, find the monitoring points from the operating parameters, and determine the parameter values of the inlet boundary parameters or the outlet boundary parameters based on the data of the three dimensions corresponding to the monitoring points.

[0040] Step S3: Based on the combustion chamber flow field simulation numerical model, determine the temperature data corresponding to each grid node in the first solid model.

[0041] Specifically, based on the first solid model, perform steady-state numerical calculation under the parameter values corresponding to the set boundary parameters and the configured constraint conditions, and output the results of the steady-state numerical calculation, that is, the temperature data on the grid nodes corresponding to each grid unit divided inside the combustion chamber.

[0042] Step S4: Perform acoustic grid division on the combustion chamber solid model to obtain a second solid model with acoustic grids.

[0043] Specifically, call a division tool different from the flow field grid division to divide the pre-constructed combustion chamber solid model into acoustic grids, and obtain the divided combustion chamber solid model, that is, the second solid model with acoustic grids. Among them, the acoustic grids can be tetrahedral grids or hexahedral grids, etc. The division tools used can be division software such as Ansys, Abaqus, and Nastran, which are suitable for finite element calculation methods.

[0044] Step S5: Based on the second solid model, the pre-obtained combustion chamber inlet boundary type, combustion chamber outlet boundary type, and the temperature data corresponding to each grid node, construct a combustion chamber acoustic numerical model.

[0045] Specifically, after dividing the acoustic grid and obtaining the second entity model with the acoustic grid, first, determine the inlet boundary type and outlet boundary type of the combustion chamber according to the structural characteristics of the inlet boundary and outlet boundary of the combustion chamber, as well as the airflow parameters of the inlet boundary and outlet boundary of the combustion chamber; secondly, according to the temperature data at the grid nodes corresponding to each flow field grid cell obtained in step S3, and determine the load conditions of the acoustic numerical model based on the temperature data at each grid node, and load them onto all nodes of the divided acoustic grid in the form of body loads.

[0046] Specifically, when determining the load conditions of the acoustic numerical model according to the temperature data at each grid node, the average value of multiple temperature values distributed inside the combustion chamber obtained in step S1 can be obtained, and this average value is used as the load condition of the acoustic numerical model. Among them, this average value is used to measure the average temperature inside the combustion chamber, so this average value can be the geometric mean or the arithmetic mean, etc.; finally, after the above preparations are completed, the acoustic numerical model of the combustion chamber can be constructed.

[0047] Step S6: Determine the acoustic natural frequency based on the acoustic numerical model of the combustion chamber.

[0048] Specifically, after constructing the acoustic numerical model of the combustion chamber, set the order of the acoustic natural frequency to be solved, and then use the acoustic numerical model of the combustion chamber to determine and output the corresponding acoustic natural frequencies of each order according to the preset order. Therefore, the number of acoustic natural frequencies depends on the set order. Therefore, the acoustic natural frequency can be one or more.

[0049] The present invention divides the combustion chamber physical model into flow field grids, and constructs a combustion chamber flow field simulation numerical model based on the first physical model with the flow field grids, the parameter values corresponding to the pre-acquired combustion chamber inlet boundary parameters and the parameter values corresponding to the combustion chamber outlet boundary parameters, and the pre-configured constraint conditions. After performing steady-state numerical calculations on the combustion chamber flow field simulation numerical model, the temperature data of each grid node corresponding to the flow field grids divided in the first physical model is output. The combustion chamber physical model is divided into acoustic grids, and based on the second physical model with the acoustic grids, the pre-determined combustion chamber inlet boundary type and outlet boundary type, and the temperature data of each grid node determined by the combustion chamber flow field simulation numerical model, a combustion chamber acoustic numerical model is constructed. When the combustion chamber acoustic numerical model is constructed, the constructed combustion chamber acoustic numerical model is used for calculation, and the same number of acoustic natural frequency values as the preset order are output, thereby obtaining the acoustic natural frequency of the gas turbine combustion chamber. This method determines the acoustic natural frequency of the combustion chamber through the constructed combustion chamber acoustic numerical model, instead of measuring the acoustic natural frequency of the combustion chamber through a large number of experiments, avoiding the defects of high test costs and complex test devices in the prior art. On the basis of ensuring low costs, this method can also quickly and conveniently obtain the acoustic natural frequency of the combustion chamber, ensuring the efficiency of the acquisition process.

[0050] In an alternative embodiment, after determining the acoustic natural frequency based on the combustion chamber acoustic numerical model, it further includes: determining a first curve based on the acoustic natural frequency and the first parameter value corresponding to the first inlet boundary parameter of the combustion chamber flow field simulation numerical model; replacing the first parameter value corresponding to the first inlet boundary parameter in the combustion chamber flow field simulation numerical model with a second parameter value, performing transient numerical calculations, and generating a calculation result; generating a second curve based on the calculation result; and verifying the acoustic natural frequency based on the first curve and the second curve to determine the accuracy of the acoustic natural frequency.

[0051] Exemplarily, the first inlet boundary parameter is any one of the multiple inlet boundary parameters of the combustion chamber flow field simulation numerical model. The abscissa of the first curve is used to indicate the combustion moment, and the ordinate of the first curve is used to indicate the second parameter value corresponding to the first inlet boundary parameter corresponding to each combustion moment.

[0052] Exemplarily, after the combustion chamber acoustic numerical model outputs the corresponding number of acoustic natural frequencies of a preset order, it is necessary to first load the output multiple acoustic natural frequencies into the parameter values corresponding to any inlet boundary parameter of the combustion chamber flow field simulation numerical model. In this embodiment, the output multiple acoustic natural frequencies can be loaded into the pressure value corresponding to the pressure inlet boundary of the combustion chamber flow field simulation numerical model. When loading, first, it is necessary to determine the combustion chamber inlet pressure pulsation disturbance time-domain diagram, i.e., the first curve, according to all the output acoustic natural frequencies and the pressure inlet boundary value of the combustion chamber flow field simulation numerical model; secondly, obtain the pressure values corresponding to each combustion moment in the first curve (i.e., the second parameter values corresponding to the first inlet boundary parameter), and replace the original pressure value (i.e., the first parameter value corresponding to the first inlet boundary parameter) in the combustion chamber flow field simulation numerical model with the pressure values corresponding to each moment in the first curve (i.e., the second parameter values) in real time according to the combustion moment; then, perform transient numerical calculation on the combustion chamber flow field simulation numerical model after modifying the parameter values corresponding to the inlet boundary parameter, and generate a calculation result, which is the pressure values corresponding to each combustion moment inside the combustion chamber after modifying the parameter values; draw the combustion chamber internal pressure pulsation disturbance time-domain diagram, i.e., the second curve, based on the combustion moment and the pressure values corresponding to each combustion moment; finally, convert the first curve and the second curve into the third curve and the fourth curve that are convenient for verifying the acoustic natural frequencies respectively, so as to verify the output acoustic natural frequencies based on the third curve and the fourth curve. The purpose of verification is to determine whether the output acoustic natural frequencies are the correct acoustic natural frequencies.

[0053] After the present invention outputs the acoustic natural frequencies through the combustion chamber acoustic numerical model, it determines the first curve according to the output acoustic natural frequencies and the parameter values corresponding to the inlet boundary parameter of the combustion chamber flow field simulation numerical model, and according to the first curve, at the corresponding combustion moment, modifies the parameter values corresponding to the inlet boundary parameter of the combustion chamber flow field simulation numerical model to the corresponding second parameter values in the first curve. Then, when the combustion chamber acoustic numerical model performs transient numerical calculation, it will adjust the corresponding first parameter values according to each combustion moment and generate calculation results corresponding to each combustion moment. According to this calculation result, the second curve is determined. Finally, based on the first curve and the second curve, the output acoustic natural frequencies of the combustion chamber acoustic numerical model are verified to ensure the accuracy of the natural frequencies output by the combustion chamber acoustic simulation model.

[0054] In an alternative embodiment, verifying the acoustic natural frequencies based on the first curve and the second curve includes: performing Fourier transform on the first curve to obtain the third curve; performing Fourier transform on the second curve to obtain the fourth curve; verifying the acoustic natural frequencies according to the third curve and the fourth curve.

[0055] Exemplarily, after generating a first curve (i.e., the time-domain diagram of the combustion chamber inlet pressure pulsation disturbance) based on the first parameter value corresponding to the first inlet boundary parameter of the acoustic natural frequency and the combustion chamber flow field simulation numerical model, the first curve is converted into a third curve (i.e., the frequency-domain diagram of the combustion chamber inlet pressure pulsation disturbance) by using the Fourier transform algorithm; after performing transient numerical calculation on the combustion chamber flow field simulation numerical model with the parameter value corresponding to the modified inlet boundary parameter and generating a second curve (i.e., the time-domain diagram of the combustion chamber internal pressure pulsation disturbance) according to the output calculation result, the second curve is converted into a fourth curve (i.e., the frequency-domain diagram of the combustion chamber internal pressure pulsation disturbance) by using the Fourier transform algorithm, and then the acoustic natural frequency can be verified based on the third curve and the fourth curve.

[0056] In the present invention, the first curve is converted into the third curve, and the second curve is converted into the fourth curve by Fourier transform. The first amplitude corresponding to the first acoustic natural frequency at the combustion chamber inlet can be read from the third curve, and the second amplitude corresponding to the first acoustic natural frequency inside the combustion chamber can be read from the fourth curve. Then, it is judged according to the first amplitude and the second amplitude whether the amplitude corresponding to the parameter inside the combustion chamber is amplified or remains unchanged when the parameter value corresponding to the combustion chamber inlet boundary parameter is modified, so as to verify the accuracy of the acoustic natural frequency.

[0057] In an optional embodiment, verifying the acoustic natural frequency based on the third curve and the fourth curve includes: obtaining a first amplitude corresponding to the first acoustic natural frequency from the third curve, where the first acoustic natural frequency is any one of multiple acoustic natural frequencies; obtaining a second amplitude corresponding to the first frequency from the fourth curve, where the first frequency is the frequency corresponding to any wave peak in the fourth curve and the first frequency is within a preset range of the first acoustic natural frequency; judging the magnitudes of the first amplitude and the second amplitude. When the second amplitude is greater than the first amplitude, or when the second amplitude is less than the first amplitude and the difference between the first amplitude and the second amplitude is less than a preset threshold, it is determined that the first acoustic natural frequency is correct.

[0058] Exemplarily, the abscissa of the third curve is used to indicate the frequency of the combustion chamber inlet boundary disturbance excitation, and the ordinate is used to indicate the first amplitude corresponding to the first inlet boundary parameter at the combustion chamber inlet. The abscissa of the fourth curve is used to indicate the frequency corresponding to the first inlet boundary parameter inside the combustion chamber, and the ordinate is used to indicate the second amplitude corresponding to the first inlet boundary parameter inside the combustion chamber.

[0059] Exemplarily, if the combustion chamber acoustic numerical model outputs 3rd-order acoustic natural frequencies, which are 81.99 Hz, 258.27 Hz, and 501.04 Hz respectively, for comparison, a first-order natural frequency of 160 Hz is artificially added, and these 4th-order acoustic natural frequencies are loaded into the pressure inlet boundary of the combustion chamber flow field simulation numerical model to generate at the inlet asFigure 3 The time-domain diagram of the pressure pulsation disturbance at the combustion chamber inlet shown, using Fourier transform, converts this time-domain diagram into as Figure 4 shown in the frequency-domain diagram of the pressure pulsation disturbance at the combustion chamber inlet. From Figure 4 it can be seen that in the frequency-domain diagram, one acoustic natural frequency corresponds to one peak. Obtain the first amplitude with the same frequency as the acoustic natural frequency, that is, the first amplitude corresponding to 81.99 Hz is approximately 4000 Pa, the first amplitude corresponding to 160 Hz is approximately 4000 Pa, the first amplitude corresponding to 258.27 Hz is approximately 4000 Pa, and the first amplitude corresponding to 501.04 Hz is approximately 4000 Pa.

[0060] After loading Figure 3 to the pressure inlet boundary of the combustion chamber flow field simulation numerical model, perform transient numerical calculation on the combustion chamber flow field simulation numerical model and output the calculation results; during the transient calculation, the pressure values corresponding to the combustion chamber inlet pressure are all modified according to Figure 3 the corresponding pressure values in it. In the calculation results of the transient numerical calculation, the pressure values corresponding to each moment inside the combustion chamber are included. Therefore, a time-domain diagram of the pressure pulsation disturbance inside the combustion chamber as shown in Figure 5 can be generated according to this calculation result, and using Fourier transform to convert Figure 5 into as Figure 6 shown in the frequency-domain diagram of the pressure pulsation disturbance inside the combustion chamber. From Figure 6 it can be seen that the frequencies and amplitudes at the peaks are respectively, the second amplitude corresponding to 80 Hz is approximately 7000 Pa, the second amplitude corresponding to 160 Hz is approximately 1500 Pa, the second amplitude corresponding to 256 Hz is approximately 6000 Pa, and the second amplitude corresponding to 501 Hz is approximately 6000 Pa.

[0061] Among them, in this embodiment, the preset neighborhood can be 2 Hz, that is, the first frequency can fluctuate within the range of the first acoustic natural frequency - 2 Hz to the acoustic natural frequency + 2 Hz. For example, 80 Hz is within the neighborhood range of 81.99 Hz. Therefore, the magnitudes of the second amplitude of 7000 Pa corresponding to 80 Hz and the first amplitude of 4000 Pa corresponding to 81.99 Hz can be directly compared, and it can be judged whether 81.99 Hz is the correct acoustic natural frequency according to the magnitudes. Since 7000 Pa > 4000 Pa, the second amplitude is greater than the first amplitude. Therefore, 81.99 Hz is the correct acoustic natural frequency.

[0062] After comparison in the same way, it is found that the first amplitude corresponding to 160 Hz is 4000 Pa, and the second amplitude corresponding to 160 Hz is 1500 Pa. Obviously, the second amplitude is smaller than the first amplitude. Then, it is necessary to calculate the difference between the first amplitude and the second amplitude, that is, 4000 Pa - 1500 Pa = 2500 Pa. At this time, it is necessary to further determine whether the difference between the two is less than the preset threshold. In this embodiment, the preset threshold is 20% of the first amplitude, 4000 Pa * 20% = 800 Pa, that is, the preset threshold is 800 Pa. Since 2500 Pa > 800 Pa, so, 160 Hz is loaded into the parameter value corresponding to the inlet boundary pressure. The amplitude corresponding to the frequency of the disturbance excitation is not amplified, and the difference from the first amplitude is greater than the preset threshold. Therefore, 160 Hz is not the correct acoustic natural frequency. It should be noted that the setting of the preset threshold is determined based on the first amplitude and a specific ratio. Among them, the size of the ratio can be determined according to the operator's experience or a large amount of experimental data, etc.

[0063] Through verification, when the output acoustic natural frequency is incorrect, the inlet boundary type and / or outlet boundary type of the combustion chamber can be modified again, and then steps S5 and S6 in the acoustic natural frequency determination method are executed again to obtain the acoustic natural frequency again, and the obtained acoustic natural frequency is verified again by the above method.

[0064] The present invention obtains the first acoustic natural frequency and the first amplitude corresponding to the first acoustic natural frequency from the third curve, obtains the second amplitude corresponding to the first acoustic natural frequency from the fourth curve, and verifies the accuracy of the first acoustic natural frequency by comparing the magnitude relationship between the first amplitude and the second amplitude. Since the setting conditions of the combustion chamber flow field simulation numerical model are all determined, the calculation results obtained by the transient calculation of this model are also determined. Therefore, the data in the fourth curve after transformation based on this calculation result are also accurate. Therefore, the accuracy of this natural frequency can be determined by comparing with the second amplitude in the fourth curve.

[0065] In an alternative embodiment, determining the first curve based on the acoustic natural frequency and the first parameter value corresponding to the first inlet boundary parameter of the combustion chamber flow field simulation numerical model includes: generating a sub-function corresponding to each acoustic natural frequency based on all acoustic natural frequencies, the first inlet boundary value of the combustion chamber flow field simulation numerical model, and a preset phase; combining the sub-functions corresponding to all acoustic natural frequencies to generate an objective function; generating the first curve based on the objective function.

[0066] Exemplarily, after the combustion chamber acoustic numerical model outputs the corresponding number of acoustic natural frequencies for a preset order, it is necessary to load the generated acoustic natural frequencies into the parameter values corresponding to any inlet boundary parameter of the combustion chamber flow field simulation numerical model. The specific loading process is as follows: Based on the output multiple acoustic natural frequencies, the parameter values corresponding to any inlet boundary parameter of the combustion chamber flow field simulation numerical model, and a preset phase value, sub-functions corresponding to each acoustic natural frequency are generated, and all the sub-chord functions are combined, and finally a target function is generated; and a first curve corresponding to the target function is generated based on the target function.

[0067] Exemplarily, if the combustion chamber acoustic numerical model outputs 3 acoustic natural frequencies corresponding to the first 3 orders, which are ω1, ω2, and ω3 respectively, the 3 acoustic natural frequencies are used as the frequency values of 3 sine functions respectively; the pressure value of the pressure boundary in the combustion chamber flow field numerical model is used as the amplitude A of the 3 sine functions at the same time, and three phase values are defined by the operator according to the actual situation, which are Since there are 3 acoustic natural frequencies, each acoustic natural frequency corresponds to a sub-function, which are respectively:

[0068]

[0069]

[0070]

[0071] And the 3 sub-functions are combined into a target function, that is:

[0072]

[0073] The time-domain graph corresponding to this target function is the third curve, and the time-domain graph is converted into a frequency-domain graph, that is, the first curve, by using Fourier transform.

[0074] The present invention generates a target function based on the acoustic natural frequencies, the parameter values of the first inlet parameter boundary of the combustion chamber flow field simulation numerical model, and the preset phase values, and generates a corresponding first curve based on the target function, thereby facilitating loading the first curve graph to the first inlet parameter boundary of the combustion chamber flow field simulation numerical model. After transient calculation through the combustion chamber flow field simulation numerical model, a second curve is obtained, so as to verify the acoustic natural frequencies through the first curve and the second curve.

[0075] In an alternative embodiment, it further includes: determining the types of the combustion chamber inlet / outlet boundaries based on the structural characteristics of the combustion chamber inlet / outlet boundaries and the airflow parameters of the combustion chamber inlet / outlet boundaries.

[0076] Exemplarily, the combustion chamber inlet / outlet boundary types include acoustic hard boundaries and acoustic soft boundaries.

[0077] Exemplarily, the boundary type of the combustion chamber inlet / outlet is determined based on the structural characteristics of the combustion chamber inlet / outlet boundary. When the combustion chamber inlet / outlet boundary has the structural characteristic that sound waves can transmit through, it indicates that the combustion chamber inlet / outlet boundary is a soft boundary; when the combustion chamber inlet / outlet boundary has the structural characteristic that sound waves cannot transmit through, it indicates that the combustion chamber inlet / outlet boundary is a hard boundary.

[0078] Exemplarily, the airflow parameter is the airflow velocity. When determining the boundary type of the combustion chamber inlet / outlet based on the airflow parameter of the combustion chamber inlet / outlet boundary, it is necessary to first obtain the local speed of sound. When the airflow velocity is greater than or equal to the local speed of sound, it indicates that the inlet / outlet boundary of the combustion chamber is a hard boundary; when the airflow velocity is less than the local speed of sound, it indicates that the inlet / outlet boundary of the combustion chamber is a soft boundary.

[0079] In an alternative embodiment, determining the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameter of the combustion chamber inlet / outlet boundary includes: making a first judgment on the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary. When it is determined that the combustion chamber inlet / outlet type is a hard boundary, the judgment process ends; or, when it is impossible to determine whether the combustion chamber inlet / outlet type is a hard boundary, a second judgment is made on the combustion chamber inlet / outlet boundary type based on the airflow parameter of the combustion chamber inlet / outlet, and the combustion chamber inlet / outlet boundary type is determined based on the result of the second judgment.

[0080] Exemplarily, after the acoustic grid is divided, it is necessary to determine the boundary type of the combustion chamber inlet / outlet according to the structural characteristics and the airflow parameter of the combustion chamber inlet / outlet. The process is to first make a first judgment according to the structural characteristics of the combustion chamber inlet / outlet, and then decide whether to make a second judgment based on the result of the first judgment. When it is determined through the first judgment that the combustion chamber inlet / outlet boundary is a hard boundary, there is no need to make a second judgment; when it is impossible to determine whether the combustion chamber inlet / outlet boundary type is a hard boundary through the first judgment, a second judgment is made on the combustion chamber inlet / outlet boundary type according to the airflow parameter of the combustion chamber inlet / outlet, and finally the type of the combustion chamber inlet / outlet boundary is determined according to the result of the second judgment.

[0081] Exemplarily, when it is impossible to determine whether the inlet / outlet boundary of the combustion chamber is a hard boundary through the first judgment, a second judgment is made. When the result of the second judgment is that the inlet / outlet boundary of the combustion chamber is a hard boundary, it is determined that the inlet / outlet boundary of the combustion chamber is a hard boundary; when the result of the second judgment is that the inlet / outlet boundary of the combustion chamber is a soft boundary, it is determined that the inlet / outlet boundary of the combustion chamber is a soft boundary.

[0082] The present invention determines the inlet / outlet boundary types of a combustion chamber by analyzing the structural characteristics of the inlet / outlet boundaries of the combustion chamber and the airflow parameters at the inlet / outlet boundaries. By this method, a preliminary judgment on the inlet / outlet boundary types of the combustion chamber can be made more objectively and accurately. Since the inlet / outlet boundary types of the combustion chamber are one of the conditions for constructing the acoustic numerical model of the combustion chamber, when the accuracy of the inlet / outlet boundary types of the combustion chamber is improved, the accuracy of the natural frequencies output by the acoustic numerical model of the combustion chamber can also be guaranteed.

[0083] The present invention discloses a device for determining the acoustic natural frequency of a gas turbine combustion chamber, as Figure 7 shown, including:

[0084] A first partitioning module 71, configured to perform a flow field grid partitioning on a pre-constructed combustion chamber solid model to obtain a first solid model carrying the flow field grid, and the first solid model includes a plurality of grid nodes;

[0085] A first construction module 72, configured to construct a combustion chamber flow field simulation numerical model according to the first solid model, pre-acquired combustion chamber inlet boundary values and combustion chamber outlet boundary values, and pre-configured constraint conditions;

[0086] An acquisition module 73, configured to determine temperature data corresponding to each grid node in the first solid model based on the combustion chamber flow field simulation numerical model;

[0087] A second partitioning module 74, configured to perform an acoustic grid partitioning on the combustion chamber solid model to obtain a second solid model carrying the acoustic grid;

[0088] A second construction module 75, configured to construct an acoustic numerical model of the combustion chamber based on the second solid model, pre-acquired combustion chamber inlet boundary types, combustion chamber outlet boundary types, and temperature data corresponding to each grid node;

[0089] A first determination module 76, configured to determine the acoustic natural frequency based on the acoustic numerical model of the combustion chamber.

[0090] In an alternative embodiment, after the first determination module, the system further includes: a second determination module, configured to determine a first curve based on the acoustic natural frequency and a first parameter value corresponding to a first inlet boundary parameter of the combustion chamber flow field simulation numerical model, where the first inlet boundary parameter is any one of a plurality of inlet boundary parameters of the combustion chamber flow field simulation numerical model, the abscissa of the first curve is used to indicate the combustion moment, and the ordinate of the first curve is used to indicate a second parameter value corresponding to the first inlet boundary parameter corresponding to each combustion moment; a first generation module, configured to perform transient numerical calculation after replacing the first parameter value corresponding to the first inlet boundary parameter in the combustion chamber flow field simulation numerical model with the second parameter value, and generate a calculation result; a second generation module, configured to generate a second curve based on the calculation result; and a verification module, configured to verify the acoustic natural frequency based on the first curve and the second curve to determine the accuracy of the acoustic natural frequency.

[0091] In an alternative embodiment, the verification module includes: a first acquisition sub-module, configured to perform Fourier transform on the first curve to obtain a third curve; a second acquisition sub-module, configured to perform Fourier transform on the second curve to obtain a fourth curve; and a verification sub-module, configured to verify the acoustic natural frequency according to the third curve and the fourth curve.

[0092] In an alternative embodiment, the verification sub-module includes: an acquisition unit, first configured to obtain a first amplitude corresponding to a first acoustic natural frequency from the third curve, where the first acoustic natural frequency is any one of a plurality of acoustic natural frequencies; a second acquisition unit, configured to obtain a second amplitude corresponding to a first frequency from the fourth curve, where the first frequency is the frequency corresponding to any wave peak in the fourth curve, and the first frequency is within a preset range of the first acoustic natural frequency; and a judgment unit, configured to judge the magnitudes of the first amplitude and the second amplitude. When the second amplitude is greater than the first amplitude, or when the second amplitude is less than the first amplitude and the difference between the first amplitude and the second amplitude is less than a preset threshold, it is determined that the first acoustic natural frequency is correct.

[0093] In an alternative embodiment, the second determination module includes: a first generation sub-module, configured to generate a sub-function corresponding to each acoustic natural frequency based on all the acoustic natural frequencies, the first inlet boundary value of the combustion chamber flow field simulation numerical model, and a preset phase; a second generation sub-module, configured to merge the sub-functions corresponding to all the acoustic natural frequencies to generate an objective function; and a third generation sub-module, configured to generate a first curve based on the objective function.

[0094] In an alternative embodiment, the system further includes: a third determination module, configured to determine the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameters of the combustion chamber inlet / outlet boundary.

[0095] In an alternative embodiment, the third determination module includes: a first judgment sub-module, configured to perform a primary judgment on the type of the combustion chamber inlet / outlet boundary based on the structural characteristics of the combustion chamber inlet / outlet boundary, and end the judgment process when it is determined that the combustion chamber inlet / outlet type is a hard boundary; a second judgment sub-module, configured to perform a secondary judgment on the type of the combustion chamber inlet / outlet boundary based on the combustion chamber inlet / outlet air flow parameters when the primary judgment cannot determine whether the combustion chamber inlet / outlet type is a hard boundary, and determine the type of the combustion chamber inlet / outlet boundary based on the result of the secondary judgment.

[0096] This embodiment provides a computer device. As Figure 8 shown, the computer device may include at least one processor 81, at least one communication interface 82, at least one communication bus 83, and at least one memory 84. Among them, the communication interface 82 may include a display screen (Display) and a keyboard (Keyboard). Optionally, the communication interface 82 may further include a standard wired interface and a wireless interface. The memory 84 may be a high-speed RAM memory (Random Access Memory, volatile random access memory), or a non-volatile memory, such as at least one disk memory. Optionally, the memory 84 may further be at least one storage device located far from the aforementioned processor 81. The processor 81 may be combined with Figure 8 the described device. An application program is stored in the memory 84, and the processor 81 calls the program code stored in the memory 84 to execute the method for determining the acoustic natural frequency of the gas turbine combustion chamber in any of the above method embodiments.

[0097] Among them, the communication bus 83 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The communication bus 83 may be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience of representation, Figure 8 only a thick line is shown in

[0098] Among them, the memory 84 may include a volatile memory, such as a random-access memory (RAM); the memory may also include a non-volatile memory, such as a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); the memory 84 may further include a combination of the above types of memories.

[0099] Among them, the processor 81 may be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP.

[0100] Among them, the processor 81 may further include a hardware chip. The above hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The above PLD may be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof. Optionally, the memory 84 is further configured to store program instructions. The processor 81 may call the program instructions to implement the method for determining the acoustic natural frequency of the gas turbine combustor in any embodiment of the present invention.

[0101] This embodiment provides a computer-readable storage medium. The computer storage medium stores computer-executable instructions, and these computer-executable instructions can execute the method for determining the acoustic natural frequency of a gas turbine combustor in any of the above method embodiments. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above types of memories.

[0102] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A method for determining the acoustic natural frequency of a gas turbine combustor, characterized in that, Including: Performing a flow field grid division on a pre - built combustion chamber solid model to obtain a first solid model carrying the flow field grid, where the first solid model includes multiple grid nodes; Constructing a combustion chamber flow field simulation numerical model according to the first solid model, the parameter values corresponding to the pre - obtained combustion chamber inlet boundary parameters and the parameter values corresponding to the combustion chamber outlet boundary parameters, and the pre - configured constraint conditions; Based on the combustion chamber flow field simulation numerical model, determining the temperature data corresponding to each of the grid nodes in the first solid model; Performing an acoustic grid division on the combustion chamber solid model to obtain a second solid model carrying the acoustic grid; Constructing a combustion chamber acoustic numerical model based on the second solid model, the pre - obtained combustion chamber inlet boundary type, combustion chamber outlet boundary type, and the temperature data corresponding to each of the grid nodes, including: determining the combustion chamber inlet boundary type and outlet boundary type according to the structural characteristics of the combustion chamber inlet boundary and outlet boundary and the airflow parameters of the combustion chamber inlet boundary and outlet boundary, determining the load conditions of the acoustic numerical model according to the temperature data of each grid node corresponding to the flow field grid unit obtained, and loading them in the form of body loads to all nodes of the divided acoustic grid; Determining the acoustic natural frequency based on the combustion chamber acoustic numerical model.

2. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 1, characterized in that, After determining the acoustic natural frequency based on the combustion chamber acoustic numerical model, it further includes: Determining a first curve based on the acoustic natural frequency and the first parameter value corresponding to the first inlet boundary parameter of the combustion chamber flow field simulation numerical model, where the first inlet boundary parameter is any one of the multiple inlet boundary parameters of the combustion chamber flow field simulation numerical model, the abscissa of the first curve is used to indicate the combustion moment, and the ordinate of the first curve is used to indicate the second parameter value corresponding to the first inlet boundary parameter at each combustion moment; After replacing the first parameter value corresponding to the first inlet boundary parameter in the combustion chamber flow field simulation numerical model with the second parameter value, performing transient numerical calculation and generating a calculation result; Generating a second curve based on the calculation result; Verifying the acoustic natural frequency based on the first curve and the second curve to determine the accuracy of the acoustic natural frequency.

3. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 2, characterized in that The verifying the acoustic natural frequency based on the first curve and the second curve includes: Performing a Fourier transform on the first curve to obtain a third curve; Performing a Fourier transform on the second curve to obtain a fourth curve; Verifying the acoustic natural frequency according to the third curve and the fourth curve.

4. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 3, characterized in that, The abscissa of the third curve is used to indicate the frequency of the combustion chamber inlet boundary perturbation excitation, and the ordinate is used to indicate the first amplitude corresponding to the first inlet boundary parameter at the combustion chamber inlet. The abscissa of the fourth curve is used to indicate the frequency corresponding to the first inlet boundary parameter inside the combustion chamber, and the ordinate is used to indicate the second amplitude corresponding to the first inlet boundary parameter inside the combustion chamber; Verifying the acoustic natural frequency based on the third curve and the fourth curve includes: Obtaining a first amplitude corresponding to a first acoustic natural frequency from the third curve, where the first acoustic natural frequency is any one of multiple acoustic natural frequencies; Obtaining a second amplitude corresponding to a first frequency from the fourth curve, where the first frequency is the frequency corresponding to any wave peak in the fourth curve, and the first frequency is within a preset range of the first acoustic natural frequency; Judging the magnitudes of the first amplitude and the second amplitude. When the second amplitude is greater than the first amplitude, or when the second amplitude is less than the first amplitude and the difference between the first amplitude and the second amplitude is less than a preset threshold, it is determined that the first acoustic natural frequency is correct.

5. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 2, characterized in that, Determining the first curve based on the acoustic natural frequency and a first parameter value corresponding to a first inlet boundary parameter of the combustion chamber flow field simulation numerical model includes: Generating a sub-function corresponding to each of the acoustic natural frequencies based on all the acoustic natural frequencies, a first inlet boundary value of the combustion chamber flow field simulation numerical model, and a preset phase; Combining the sub-functions corresponding to all the acoustic natural frequencies to generate an objective function; Generating the first curve based on the objective function.

6. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 1, characterized in that, The method further includes: Determining the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameters of the combustion chamber inlet / outlet boundary.

7. The method for determining the acoustic natural frequency of a gas turbine combustor according to claim 6, characterized in that, Determining the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary and the airflow parameters of the combustion chamber inlet / outlet boundary includes: Making a first judgment on the combustion chamber inlet / outlet boundary type based on the structural characteristics of the combustion chamber inlet / outlet boundary. When it is judged that the combustion chamber inlet / outlet type is a hard boundary, the judgment process ends; Or, when it is impossible to determine whether the combustion chamber inlet / outlet type is a hard boundary, making a second judgment on the combustion chamber inlet / outlet boundary type based on the combustion chamber inlet / outlet airflow parameters, and determining the combustion chamber inlet / outlet boundary type based on the result of the second judgment.

8. An apparatus for determining the acoustic natural frequency of a gas turbine combustor, characterized in that Including: A first partitioning module for performing a flow field grid partition on a pre-constructed combustion chamber solid model to obtain a first solid model carrying the flow field grid, where the first solid model includes multiple grid nodes; A first construction module for constructing a combustion chamber flow field simulation numerical model according to the first solid model, pre-obtained combustion chamber inlet boundary values and combustion chamber outlet boundary values, and pre-configured constraint conditions; An acquisition module for determining temperature data corresponding to each of the grid nodes in the first solid model based on the combustion chamber flow field simulation numerical model; A second partitioning module for performing an acoustic grid partition on the combustion chamber solid model to obtain a second solid model carrying the acoustic grid; A second construction module for constructing an acoustic numerical model of a combustion chamber based on the second entity model, pre-acquired combustion chamber inlet boundary types, combustion chamber outlet boundary types, and temperature data corresponding to each of the grid nodes, including: determining the inlet boundary type and outlet boundary type of the combustion chamber according to the structural characteristics of the combustion chamber inlet boundary and outlet boundary and the airflow parameters of the combustion chamber inlet boundary and outlet boundary, determining the load conditions of the acoustic numerical model according to the temperature data of each grid node corresponding to each flow field grid unit obtained, and loading the load conditions onto all nodes of the divided acoustic grid in the form of body loads; A first determination module for determining the acoustic natural frequency based on the acoustic numerical model of the combustion chamber.

9. A computer device, characterized in that, including: A memory and a processor, the memory and the processor are communicatively connected to each other, the memory is used for storing a computer program, and when the computer program is executed by the processor, the processor executes the method for determining the acoustic natural frequency of a gas turbine combustion chamber according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium is used for storing computer instructions, and when the computer instructions are executed by a processor, the method for determining the acoustic natural frequency of a gas turbine combustion chamber according to any one of claims 1 to 7 is implemented.

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