Spraying pipe ablation calculation method and device and storage medium

Abstract

The invention discloses a nozzle ablation calculation method and device and a storage medium, and belongs to the technical field of aerospace. Comprising the following steps: 1, acquiring spectral data of main components of high-temperature fuel gas in a spray pipe, and processing the spectral data to obtain radiation data of the high-temperature fuel gas; 2, according to the high-temperature fuel gas radiation data obtained in the step 1, obtaining actual temperature offline intensity, broadening of Doppler and Lorentz effects and monochromatic absorption coefficients, and calculating a Planck average absorption coefficient; 3, inputting the Planck average coefficient into a two-way coupling model, wherein the two-way coupling model introduces a DO model and simulates a wall surface retreating process by adopting a dynamic grid technology; and iteratively updating the flow field, and outputting distribution data of the ablation rate and the ablation amount of the spray pipe. When numerical simulation is carried out on the nozzle ablation problem, a reasonable algorithm is introduced, a proper radiation heat exchange mathematical model is combined, radiation heat is considered in the calculation process, and the method has extremely high practical application value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aerospace technology, in particular to a nozzle ablation calculation method, device and storage medium. BACKGROUND

[0002] In the development of aerospace power, the nozzle as a key component, its working environment is extremely harsh, often face high temperature, high pressure and high speed impact and other extreme conditions, resulting in nozzle material ablation, affecting the stability and performance of the engine. Especially carbon-based material nozzle, because of its excellent physical and chemical properties are widely used, but its ablation performance has become a research hotspot. The present application is compared with the existing technology at home and abroad, and the closest existing technology as follows: The closest existing technology to the present application includes: 1) the patent entitled "Solid rocket engine C / C composite nozzle ablation behavior modeling and simulation method" (application unit: South China University of Technology, application number: CN113722830B, publication date: 2021.11.30); 2) the patent entitled "Multi-field coupling near-field dynamics simulation method for surface ablation morphology simulation" (application unit: Shanghai Jiaotong University, application number: CN119026415A, publication date: 2024.11.26).

[0003] Compared with the former two, the core advantage of the present application is that the above two close patents focus on "material multi-scale ablation response" and "numerical simulation of complex morphology evolution", respectively, while the present application focuses on more basic and common problems under the background of nozzle ablation problem. While considering the change of nozzle profile during ablation, the present application introduces the DO radiation model and couples the HITRAN database spectrum data to realize high-precision calculation of radiation heat flux in nozzle ablation simulation, making the whole ablation process closer to the real situation. Under the background of nozzle ablation problem, the consideration of the influence of radiation heat flow is of great significance, because the working environment of the nozzle is relatively harsh, belonging to high temperature and high pressure environment. Since the relationship between heat transfer and convective heat transfer and temperature difference is linear, while the relationship between radiation heat and temperature difference is quartic. Therefore, radiation heat has a significant impact on the inner wall temperature distribution of the nozzle during the nozzle ablation process, and its influence on the inner wall temperature distribution will also affect the whole ablation process. The bidirectional coupling model established in the present application realizes the accurate simulation of the strong coupling process of "flow-chemical reaction-radiation heat transfer-structure evolution". This improvement significantly improves the accuracy of wall temperature field and ablation rate prediction. The present application can not only be used as an independent high-precision calculation method, but also can improve the prediction reliability and engineering application value of various advanced ablation response models. SUMMARY

[0004] The present application considers that the radiation heat has a significant influence on the temperature distribution of the inner wall of the nozzle during the nozzle ablation process, and in the numerical simulation of the nozzle ablation problem, a reasonable algorithm is introduced, and a suitable radiation heat mathematical model is combined, and in the calculation process, the consideration of the radiation heat is extremely practical and has positive significance for the accuracy of the simulation results.

[0005] The present application provides a kind of nozzle ablation calculation method, comprising: Step 1: obtaining the spectrum data of the main components of high-temperature gas in the nozzle, processing the spectrum data, and obtaining the radiation data of high-temperature gas; Step 2: according to the high-temperature gas radiation data obtained in step 1, the line intensity, Doppler and Lorentz effect broadening, monochromatic absorption coefficient calculation Planck average absorption coefficient under actual temperature; Step 3: input the Planck average coefficient into the two-way coupling model, the two-way coupling model is introduced DO model and adopts dynamic grid technology to simulate wall retreat process;Iterative update flow field, output nozzle ablation rate and ablation amount distribution data.

[0006] Further, the adjustment line intensity adapts to non-standard temperature is: wherein, is the spectral line intensity at actual temperature; is the spectral line intensity at reference temperature; is the partition function at reference temperature; is the partition function at actual temperature; is the actual temperature; is the reference temperature; is the second radiation constant; is the low-energy state energy.

[0007] Further, the Doppler broadening half-width is: wherein, is the Avogadro constant; is the molar mass of isotope molecule; is the Boltzmann constant; is the spectral line center wave number; is the vacuum light speed; Lorentz broadening half-width is: wherein, is the total pressure of gas system; is the temperature broadening index; is the air broadening coefficient; is the self-broadening coefficient; reference partial pressure of the target gas component; partial pressure of the target gas component.

[0008] Further, the monochromatic absorption coefficient is specifically: Step 2.1: In the atmosphere, the spectral line center wavenumber widens near the transition, and the Lorentz line shape function is: wherein, is the Lorentz line shape function; is the spectral calculation point position wavenumber; is the Lorentz pressure broadening half-width; is the pressure shift coefficient; Step 2.2: The Gaussian line shape dominated by Doppler broadening is: wherein, is the Gaussian line shape; is the Doppler broadening half-width; Step 2.3: Convolution of the Gaussian line shape and the Lorentz line shape; for engineering calculations in the nozzle environment, the approximation is . wherein, is the weight coefficient of the broadening mechanism; Step 2.4: The monochromatic absorption coefficient at the wavenumber (cm -1 ) is calculated as: Further, the Planck mean absorption coefficient is: wherein, is the blackbody total radiance; is a constant.

[0009] Further, in step 3, the DO radiation model is: wherein, is the radiation power per unit solid angle, per unit area at a specific wavenumber v; is the radiation heat flow vector; G is the integral of all direction incident radiation.

[0010] Further, in step 3, the dynamic mesh technique is used to solve the ablation rate of the radiation transfer equation type calculation according to the DO radiation mode, and the node position and speed of the nozzle wall surface are updated in real time to reflect the transient change of the nozzle profile.

[0011] Further, in step 3, the pressure inlet, pressure outlet, transmittance and absorption rate are set, and a two-way coupling model is used to simulate the radiation heat transfer in the nozzle to obtain the ablation rate and ablation amount distribution of the nozzle; wherein, is the optical depth; wherein, is the column density; is the monochromatic absorption coefficient; is the volume number density of the absorbing molecules along the target path.

[0012] The present application also provides a computer device / equipment / system, which comprises a memory, a processor and a computer program stored in the memory, and the processor implements the steps of the nozzle ablation calculation method according to any one of the above when executing the computer program.

[0013] The present application also provides a computer readable storage medium, which stores a computer program / instruction, and the computer program / instruction implements the steps of the nozzle ablation calculation method according to any one of the above when executed by a processor.

[0014] The present application also provides a computer program product, which comprises a computer program / instruction, and the computer program / instruction implements the steps of the nozzle ablation calculation method according to any one of the above when executed by a processor.

[0015] The present application has the following beneficial effects: The algorithm of the present application, in combination with the dynamic mesh technique, significantly improves the prediction accuracy of the nozzle ablation rate and ablation amount by introducing a radiation heat transfer model, making it closer to the actual experimental results and improving the prediction accuracy. Unlike existing research which simplifies the problem as a steady-state problem, the algorithm of the present application can simulate the process of gradually increasing ablation rate at the initial stage of the nozzle and the influence of surface shape change on the ablation process, realizing non-steady-state full-process numerical simulation. The algorithm of the present application can be applied to the design and optimization of solid rocket engine nozzles, providing technical support and reference for improving engine performance and stability, and has high engineering application value. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 Flow chart of the nozzle ablation calculation method of the present application; Figure 2 Schematic diagram of the calculation model of the nozzle ablation calculation method of the present application; Figure 3 Comparison chart of the calculation effect of the nozzle ablation calculation method of the present application; wherein, figure (a) is the nozzle wall surface temperature distribution considering the radiation model, figure (b) is the nozzle wall surface temperature distribution without considering the radiation model; figure (c) is the nozzle wall surface ablation rate distribution considering the radiation model; and figure (d) is the nozzle wall surface ablation rate distribution without considering the radiation model. DETAILED DESCRIPTION

[0017] The present application will be further described below in combination with the drawings.

[0018] The bidirectional coupling model of the present application includes an integrated radiation transmission and chemical reaction response module and a dynamic mesh module capturing structural deformation; both form a closed loop feedback through real-time data exchange.

[0019] The radiation transmission and chemical reaction response module calculates the local ablation rate by solving the flow field and surface chemical reaction containing multi-species transmission; at the same time, by using high-precision spectral data based on the HITRAN database, the radiation transmission equation is solved by the discrete ordinate method (DO model) to accurately obtain the radiation heat flux acting on the wall and the radiation source term inside the gas. The radiation heat flux is directly coupled into the wall chemical reaction as an energy boundary condition, which significantly affects the wall temperature and ablation rate.

[0020] The dynamic mesh module then updates the node position and velocity of the nozzle wall in real time according to the ablation rate calculated by the radiation transmission and chemical reaction response module, accurately reflecting the transient change of the nozzle profile.

[0021] The bidirectional coupling of the model is reflected in that the dynamic mesh module feeds back the updated geometric features to the flow field solver, changing the distribution of the flow field, temperature field and concentration field; and the changed field data are input to the property response module to recalculate the new ablation rate and radiation heat flux. Such a cycle iteration realizes accurate simulation of the strong coupling process of "flow-chemical reaction-radiation heat transfer-structural evolution", significantly improves the prediction accuracy of the nozzle ablation rate and ablation amount, makes it closer to the actual experimental results, and improves the prediction accuracy.

[0022] Example 1 This invention uses PyCharm Community Edition with Python 3.7 as its core, combined with scientific computing libraries such as NumPy and MatePlotlib, to write a program that calls HAPI to access the HITRANonline website and uses the Python program to call the HITRAN database to obtain line-by-line molecular spectra of the main components of high-temperature fuel gas. The spectral data of the main components of the fuel gas are obtained. The processing of the spectral data is as follows... Figure 1 The algorithm flowchart is shown. The acquired gas molecule radiation data is processed to obtain the absorption coefficient versus wavenumber curves under specific temperature and pressure conditions. The Planck-mean absorption coefficient of the gas component is calculated as follows: a. Adjust the linear strength to accommodate non-standard temperatures. The strength at temperatures different from 296K (HITRAN reference temperature) is calculated using formulas (1) and (2): (1) (2) in, The intensity of the spectral line is at the actual temperature; Isotope abundance; Einstein's coefficient; It is the speed of light in a vacuum; It is the second radiation constant; Low-energy state statistical weights; It is the energy of a low-energy state; The center wavenumber of the spectral line; Absolute temperature; The intensity of the spectral line at that temperature; The spectral line intensity is at the reference temperature; For reference temperature; The partition function at the reference temperature; This is the partition function at the actual temperature.

[0023] Formula (2) processes the database parameters, gives the definition of spectral lines, establishes the basic parameters of spectral lines, and provides the basic parameters for Formula (1); Formula (1) calculates the spectral line intensity at the actual temperature based on the temperature-corrected spectral line intensity. .

[0024] b. Calculate the linewidth considering the Doppler and Lorentz effects; When using a database, the Voigt line type is typically used; this line type is a Lorentz (pressure spread) profile. L (ν) and Gaussian (Doppler extension) profile ƒ G The convolution of (ν). The maximum half-width (HWHM) of the Doppler spread component is given by the following equation: (3) in, It is Avogadro's constant; The molar mass of the isotope molecule; Boltzmann's constant; The center wavenumber of the spectral line; Gas under pressure, temperature T (K), p (atm), and partial pressure P self Lorentz (pressure broadening) HWHM at (atm): (4) In the formula Expand Lorenz by half a width; Temperature broadening index; This refers to the air spanning factor; This refers to the total pressure of the gas system. The partial pressure of the target gas component; Self-expansion coefficient.

[0025] Since the shape of the spectral line is determined by both molecular thermal motion and molecular collisions, at the actual temperature, the Doppler span determined by molecular thermal motion can be solved by equation (4), and the pressure broadening determined by molecular collisions can be solved by equation (5).

[0026] c. Calculation of absorption coefficient In the atmosphere, the center wavenumber ν of the spectral line during the transition ij The area widens in the vicinity, and its expansion is represented by a normalized linear function: (5) in, It is a Lorentz linear function; Calculate the wavenumber of the point location in the spectrum; To widen the Lorentz pressure by half; This is the pressure displacement coefficient; In low-pressure atmospheres where pressure broadening of spectral lines dominates, if a Lorentz distribution can be assumed, then in the low-pressure environment of the upper atmosphere, the linear and Gaussian distributions dominated by Doppler expansion can be assumed as follows: (6) in, It is a Gaussian line type; To widen the half-width for Doppler; In nozzle ablation problems, because the nozzle is subjected to extreme conditions of high temperature, high pressure, and high speed, a single Gaussian profile f... L Or Lorentz line f GNeither of these methods is sufficient to accurately describe the actual spectral line shape; therefore, a more detailed Voigt line type is required, which is the convolution of the Gaussian and Lorentz line types. (7) For engineering calculations in nozzle environments, the following approximate expression is often used: (8) in, The weighting coefficients for the broadening mechanism; In wavenumber (cm) -1 The monochromatic absorption coefficient at () is (9) Formula (9) calculates the monochromatic absorption coefficient at the corresponding wavenumber, which is the product of the spectral line intensity at the actual temperature obtained from formula (2) and the Voigt line shape in equation (8).

[0027] d. Planck's average absorption coefficient (10) In the formula, This represents the total radiative power of the blackbody. The monochromatic absorption coefficient at the wavenumber calculated by formula (9) is given.

[0028] By processing the acquired spectral data using the line-by-line method, the curves of the absorption coefficients of the gas components under the working environment of the nozzle under temperature and pressure as a function of wavenumber are obtained. This yields the transmission and absorption spectra of each molecule under the required operating conditions. The Planck average absorption coefficient of the gas components is obtained through the analysis and calculation of the spectral data. Combined with the gas characteristic parameters required by the DO radiation model, the radiation heat transfer problem in the nozzle is described using the DO model in the FLUENT commercial software.

[0029] The DO radiation model is as follows: (11) (12) in, It is the radiated power per unit solid angle and per unit area at a specific wavenumber ν. It is the radiative heat flux vector. G This is the integral of the incident radiation in all directions.

[0030] Equation (11) is the radiative transfer equation, and Equation (12) is the mathematical description of the radiation source term using the Planck average approximation. Equation (11) describes the energy balance when radiation propagates in a medium, i.e., the change in radiation intensity = radiation emitted by the medium - radiation absorbed by the medium. Equation (12) describes the contribution of radiative energy to the local energy balance, i.e., the change in radiative energy = radiation emitted by the medium - radiation absorbed by the medium.

[0031] By coupling the influence of radiative heat on temperature distribution with flow and energy equations and iteratively solving the equations, combined with dynamic mesh technology, a more accurate description of the ablation process can be achieved.

[0032] Calculation process and result verification: To verify the reliability of the algorithm of this invention, BATES was selected as the calculation model to conduct numerical simulation of rocket engine ablation. The reliability of the algorithm was verified by comparing it with the BATES database, a standard equivalent for measuring and comparing the performance of solid rocket engines.

[0033] Calculation setup: The nozzle inlet is set as a pressure inlet, the nozzle outlet as a pressure outlet, and the nozzle inner wall is set as a heat transfer coupling wall and a surface where heterogeneous reactions occur. The heat flux density at all wall surfaces is zero, meaning the walls are adiabatic. The calculation uses a two-dimensional axisymmetric model of the BATES nozzle, such as... Figure 2 The calculation model is shown in the diagram.

[0034] First, based on the engine's operating conditions and the nozzle geometry model, the initial boundary conditions are set as follows: pressure 6 MPa, temperature 3000 K. The absolute pressure at the pressure outlet is 1 atm. Using the Do radiation model, considering radiative heat transfer between the combustion gas and the nozzle wall, the absorption coefficient of the mixed combustion gas is input.

[0035] By setting transmittance and absorptivity, and then updating flow field parameters, species concentration distribution, and mesh shape through iterative calculations, the distribution maps of nozzle ablation rate and ablation amount are finally obtained. The accuracy and reliability of the algorithm are demonstrated through comparison with actual experimental data.

[0036] (13) (14) in, Transmittance; Absorption rate; The dimensionless optical depth is calculated using formula (15) by multiplying the absorption coefficient by the column density of the absorbing molecules. (molecular cm) -2 The dimensionless optical depth is formed by the formula (9). The optical depth is a dimensionless quantity that represents the degree of attenuation of radiation as it propagates in the medium. With formula (16) To obtain.

[0037] (15) (16) in, For column density; For the volume number density of absorber molecules along the target path; in particular, if If it is constant on the target path, then .

[0038] Based on the Beer-Lambert law, the transmittance formula (13) and absorptivity formula (14) are derived. Transmittance represents the proportion of radiation remaining after passing through the medium, and absorptivity represents the proportion absorbed by the medium. In the nozzle environment, this refers to the distribution ratio of radiant energy absorbed by the combustion gas itself and radiated to the nozzle wall. The optical depth is calculated using formula (15). Substituting directly into formulas (13) and (14), the spectral transmittance and absorptivity at a specific wavenumber are used to solve for the attenuation behavior of radiative energy in the medium. The above calculation of spectral transmittance and absorptivity is a direct result of the Beer-Lambert law based on a uniform path. However, in the actual non-uniform, multidimensional flow field of the nozzle, radiative energy comes from all directions, and its transmission is a complex integral-differential process. Formulas (13) and (14) provide a basis for solving the radiative transfer equation (RTE) to obtain the global radiative heat flux distribution.

[0039] By comparing cases that consider and ignore radiative heat transfer, the influence of radiative heat transfer on the nozzle temperature field and ablation rate distribution is discussed.

[0040] Depend on Figure 3 The comparison chart of wall temperature distribution and ablation rate with and without radiation models shows the following pattern: In the convergence section, the temperature field distribution on the nozzle wall exhibits the following characteristics: When radiative heat transfer is neglected, the temperature distribution on the convergence section wall follows a "V" shape, and the temperature remains below 1500K. The peak temperature occurs at the nozzle throat, and even at the throat, the peak temperature is below 2500K. When radiative heat transfer is considered, the temperature distribution on the convergence section wall is higher on the left and lower on the right. In the convergence section, the wall temperature rapidly rises to nearly 3500K. This is because the gas radiation intensity is proportional to the fourth power of the temperature, resulting in a significantly enhanced radiative heating effect.

[0041] Temperature field distribution in the expansion section: After the high-temperature gas is accelerated through the nozzle throat, the overall gas temperature in the divergence section is relatively low, and the influence of radiative heat transfer on the inner wall temperature field is small. Therefore, compared with the convergence section, the expansion section is less sensitive to radiative heat transfer, and the consideration of the radiation model has little impact on the temperature distribution in this section.

[0042] From the perspective of ablation rate, whether or not a radiation model is used, the ablation rate distribution trend of the nozzle wall is the same. The ablation rate increases with time and reaches a peak near the nozzle throat. The difference is that when the radiation model is considered, the peak ablation rate at the nozzle throat is 0.45 mm / s, compared to 0.35 mm / s when the radiation model is not considered.

[0043] The calculation results show that radiative heat transfer has a significant impact on the calculation results in the initial stage of nozzle operation, especially in the convergence phase. However, in the expansion phase, as the nozzle wall temperature gradually reaches equilibrium, the influence of radiative heat transfer weakens. Therefore, whether or not radiative heat transfer is considered has little impact on the distribution of wall temperature and ablation rate.

[0044] When performing transient calculations on nozzle ablation, the radiation model has a significant impact on the calculation results. By incorporating the radiation model in conjunction with dynamic mesh technology, the calculation results are more consistent with experimental results and can more realistically and accurately reflect the nozzle ablation process.

[0045] In particular, in some preferred embodiments of the present invention, a computer device is also provided, including a memory and a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the nozzle ablation calculation method described in any of the above embodiments.

[0046] In some other preferred embodiments of the present invention, a computer-readable storage medium is also provided, on which a computer program / instruction is stored, wherein when the computer program is executed by a processor, the steps of the nozzle ablation calculation method described in any of the above embodiments are implemented.

[0047] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the above-described nozzle ablation calculation method embodiments, which will not be repeated here.

[0048] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more N executable instructions for implementing custom logic functions or processes, and the scope of preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of the invention pertain.

[0051] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0052] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0053] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0054] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0055] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for calculating nozzle ablation, characterized in that, include: Step 1: Obtain spectral data of the main components of the high-temperature gas inside the nozzle, process the spectral data to obtain the radiation data of the high-temperature gas; Step 2: Based on the high-temperature gas radiation data obtained in Step 1, obtain the actual temperature upper limit intensity, Doppler and Lorentz effect broadening, monochromatic absorption coefficient, and calculate the Planck average absorption coefficient. Step 3: Input the Planck average coefficients into the two-way coupled model, which is to introduce the DO model and use dynamic mesh technology to simulate the wall retreat process; The flow field is iteratively updated, and the distribution data of nozzle ablation rate and ablation amount are output.

2. The nozzle ablation calculation method according to claim 1, characterized in that, The adjustment line strength is adapted to non-standard temperatures as follows: in, The intensity of the spectral line is at the actual temperature; The spectral line intensity is at the reference temperature; The partition function at the reference temperature; The partition function is given at the actual temperature. This refers to the actual temperature. For reference temperature; It is the second radiation constant; It represents the energy of a low-energy state.

3. The nozzle ablation calculation method according to claim 1, characterized in that, The Doppler broadening half-width is: in, It is Avogadro's constant; The molar mass of the isotope molecule; Boltzmann's constant; The center wavenumber of the spectral line; It is the speed of light in a vacuum. Lorenz widens the half-width as follows: in, This refers to the total pressure of the gas system. Temperature broadening index; This refers to the air spanning factor; This is the self-expansion factor; The reference partial pressure of the target gas component; This represents the partial pressure of the target gas component.

4. The nozzle ablation calculation method according to claim 1, characterized in that, The monochromatic absorption coefficient is specifically: Step 2.1: In the atmosphere, the center wavenumber of the spectral line during the transition. The width increases in the vicinity, and the Lorentz linear function is: in, It is a Lorentz linear function; Calculate the wavenumber of the point location in the spectrum; To widen the Lorentz pressure by half; This is the pressure displacement coefficient; Step 2.2: The Gaussian line shape dominated by Doppler extension is as follows: in, It is a Gaussian line type; To widen the half-width for Doppler; Step 2.3: Convolve the Gaussian and Lorentz curves; for engineering calculations in the nozzle environment, the approximation is... ; in, The weighting coefficients for the broadening mechanism; Step 2.4: Calculate the wave number (cm) -1 The monochromatic absorption coefficient at () is:

5. The nozzle ablation calculation method according to claim 1, characterized in that, The Planck average absorption coefficient is: in, This represents the total radiative power of a blackbody. It is a constant.

6. The nozzle ablation calculation method according to claim 1, characterized in that, In step 3, the radiative transfer equation of the DO radiation model is: in, The radiated power per unit solid angle and per unit area at a specific wavenumber ν; G is the radiative heat flux vector; G is the integral of incident radiation in all directions.

7. The nozzle ablation calculation method according to claim 6, characterized in that, In step 3, the dynamic mesh technology calculates the ablation rate based on the DO radiation model by solving the radiation transfer equation, and updates the node positions and velocities of the nozzle wall in real time to reflect the transient changes in the nozzle profile.

8. The nozzle ablation calculation method according to claim 1, characterized in that, In step 3, the pressure inlet, pressure outlet, and transmittance are set. and absorption rate We began by using a two-way coupling model to simulate the radiative heat transfer inside the nozzle, and obtained the nozzle ablation rate and ablation amount distribution. in, Optical depth; in, For column density; The monochromatic absorption coefficient; This refers to the volume number density of the absorbing molecules along the target path.

9. A computer device / equipment / system, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the method according to any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program / instructions stored thereon, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method according to any one of claims 1 to 8.

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