Method and system for predicting submodal heat flux in hypersonic thermochemical nonequilibrium flow

Abstract

The present invention proposes a method and system for predicting the modal heat flux of hypersonic thermochemical non-equilibrium flow, which relates to the technical field of hypersonic heat flux prediction. It includes constructing a group of N-S equations; characterizing the thermochemical non-equilibrium effects in the hypersonic flow field based on the vibration-electron energy source term and the chemical reaction source term; obtaining the translational-rotational thermal conductivity, vibration-electron thermal conductivity, and component mass diffusion coefficient and viscosity coefficient corresponding to the two temperature models based on the transport model; iteratively solving the N-S equations to obtain the translational-rotational modal heat flux density and the vibration-electron modal heat flux density according to Fourier's law, and simultaneously obtaining the chemical diffusion heat flux density; summing the translational-rotational modal heat flux density, the vibration-electron modal heat flux density, and the chemical diffusion heat flux density to obtain the total heat flux density. The present invention extracts the translational-rotational heat flux, the vibration-electron heat flux, and the surface chemical diffusion heat flux from the total heat flux, clarifying the heat flux composition.

Description

Technical Field

[0001] The present invention belongs to the technical field of hypersonic heat flow prediction, and in particular relates to a method and system for predicting submodal heat flow in hypersonic thermochemical non-equilibrium flow. Background Art

[0002] Hypersonic speed generally refers to flight with a Mach number greater than 5. During the re-entry process of the aircraft, the extremely high flight speed causes the free air flow to undergo shock wave compression and viscous stagnation in front of the aircraft, generating a strong bow shock wave at the leading edge of the aircraft. A large amount of kinetic energy in the air is converted into internal energy, and the flow field temperature rises sharply, reaching 10 4 Kelvin. In this case, the harsh aerodynamic thermal environment causes severe aerodynamic heating on the reentry vehicle surface, seriously threatening the vehicle's safety. Therefore, it is necessary to accurately predict the heat flux on the vehicle surface to provide guidance for the vehicle's thermal protection design.

[0003] However, the complex thermochemical nonequilibrium effects present in the flow field around a vehicle make heat flow prediction extremely difficult. Thermochemical nonequilibrium refers to the fact that high temperatures within the flow field excite the vibrational and electronic energy modes of air components, simultaneously inducing chemical reactions in the air, such as molecular dissociation, atomic recombination, and electron ionization. These thermodynamic changes and chemical reactions require molecular collisions, which takes a considerable amount of time. When the energy relaxation time of air components is comparable to the characteristic flow time, thermodynamic nonequilibrium occurs; when the chemical reaction time is comparable to the characteristic flow time, chemical nonequilibrium occurs. The coupling of these two factors creates a complex thermochemical nonequilibrium effect, a key characteristic of hypersonic flow. Complex thermochemical nonequilibrium effects introduce uncertainty into the prediction of aerodynamic heating for hypersonic reentry vehicles. Therefore, continued research into hypersonic aeroheating under the influence of thermochemical nonequilibrium is of great significance.

[0004] There are multiple methods for predicting reentry vehicle aeroheating, including engineering correlations and computational fluid dynamics (CFD) methods. Engineering correlations include the classic Fay-Riddell equation for calculating stagnation point heat flux and the Lees equation for calculating laminar heat flux in blunt bodies. When using CFD to solve hypersonic aeroheating, it is necessary to model the thermochemical nonequilibrium effects in the flow field. Thermodynamic nonequilibrium effects are generally characterized using multi-temperature models, while chemical nonequilibrium effects are typically characterized using the classic 5-, 7-, or 11-component chemical kinetic models of Park, Gupta, and Dunn-Kang. However, both CFD and engineering correlations can only predict the total convective heat flux; the heat fluxes corresponding to different internal energy modes under thermochemical nonequilibrium effects and the chemical diffusion heat have not yet been extracted. Further extraction of submodal heat fluxes and chemical diffusion heat is crucial for further understanding thermochemical nonequilibrium effects, clarifying the heat flux components, and focusing on the heat fluxes that contribute the most. Summary of the Invention

[0005] To overcome the shortcomings of the aforementioned prior art, the present invention provides a method and system for predicting submodal heat flux in hypersonic thermochemical nonequilibrium flows. This method, based on the general Navier-Stokes equations, supplements the transport equations and closed-loop models for the corresponding physical quantities. A two-temperature model (translational-rotational temperature and vibrational-electronic temperature) and a multi-component chemical reaction model (5, 7, and 11 components) are used to characterize the thermochemical nonequilibrium effects in the flow field. The hypersonic flow field is numerically solved to predict the convective heat flux on the aircraft surface. The translational-rotational modal heat flux, the vibrational-electronic modal heat flux, and the surface chemical diffusion heat flux are simultaneously extracted from the total heat flux. The contribution of each submodal heat flux to the total heat flux is then given, clarifying the heat flux composition.

[0006] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0007] A first aspect of the present invention provides a method for predicting the partial modal heat flow of hypersonic thermochemical non-equilibrium flow. The method comprises the following steps:

[0008] Construct the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation;

[0009] Characterize the thermochemical non-equilibrium effects in hypersonic flow fields based on vibration-electron energy source terms and chemical reaction source terms;

[0010] Based on the transport model, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient and component viscosity coefficient corresponding to the two-temperature model are obtained;

[0011] The closed NS equations are iteratively solved until convergence. According to Fourier's law, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity and component mass diffusion coefficient are combined to obtain the translational-rotational and vibrational-electronic modal heat flux densities corresponding to the translational-rotational and vibrational-electronic temperatures, and the chemical diffusion heat flux density is also obtained.

[0012] The total heat flux density is obtained by adding the translational-rotational modal heat flux density, the vibrational-electronic modal heat flux density and the chemical diffusion heat flux density.

[0013] A second aspect of the present invention provides a hypersonic thermochemical non-equilibrium flow submodal heat flow prediction system.

[0014] Hypersonic thermochemical non-equilibrium flow submodal heat flow prediction system, including:

[0015] The NS equations building module is configured to: build the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation;

[0016] The source term module is configured to characterize the thermochemical non-equilibrium effects in the hypersonic flow field based on the vibration-electron energy source term and the chemical reaction source term;

[0017] The transport property calculation module is configured to: obtain the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient, and component viscosity coefficient corresponding to the two-temperature model based on the transport model;

[0018] The prediction and solution module is configured to iteratively solve the closed NS equations until convergence, and obtain the translational-rotational modal heat flux density and vibrational-electronic modal heat flux density corresponding to the translational-rotational temperature and vibrational-electronic temperature according to Fourier's law by combining the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, and component mass diffusion coefficient, and simultaneously obtain the chemical diffusion heat flux density;

[0019] The summing module is configured to sum the translation-rotational modal heat flux density, the vibration-electronic modal heat flux density, and the chemical diffusion heat flux density to obtain a total heat flux density.

[0020] A third aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements the steps in the hypersonic thermochemical non-equilibrium flow submodal heat flow prediction method as described in the first aspect of the present invention.

[0021] A fourth aspect of the present invention provides an electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor. When the processor executes the program, the steps of the method for predicting the submodal heat flow of hypersonic thermochemical non-equilibrium flow as described in the first aspect of the present invention are implemented.

[0022] One or more of the above technical solutions have the following beneficial effects:

[0023] The present invention provides a method and system for predicting submodal heat flux in hypersonic thermochemical non-equilibrium flow. Based on a two-temperature model (translational-rotational temperature, vibrational-electronic temperature) and a multi-component chemical reaction model (5, 7, and 11 components), the hypersonic vehicle flow field is numerically solved, and the surface heat flux is predicted by considering completely non-catalytic and super-catalytic wall boundary conditions respectively. Not only the total convective heat flux is given, but also the translational-rotational modal heat flux, vibrational-electronic modal heat flux, and chemical diffusion heat flux are extracted from the total heat flux, and the contribution of each submodal heat flux to the total heat flux is given.

[0024] When numerically solving the hypersonic vehicle flow field, the present invention considers a two-temperature model involving translational-rotational temperature and vibrational-electronic temperature, deriving the total thermal conductivity corresponding to each. These two total thermal conductivities are then used to determine the translational-rotational heat flux and the vibrational-electronic heat flux. Furthermore, the chemical diffusion heat flux is derived based on the component diffusion coefficients. Ultimately, this method enables the prediction of submodal heat flux for hypersonic thermochemical nonequilibrium flows.

[0025] The method of this invention numerically solves the hypersonic thermochemical nonequilibrium flow field of a 1-meter spherical head model under eight classic flight conditions, considering both completely non-catalytic and super-catalytic wall conditions. The total heat flux, translational-rotational modal heat flux, vibrational-electronic modal heat flux, and chemical diffusion heat flux are presented for each condition. The proportion of each modal heat flux is also presented: under non-catalytic conditions, translational-rotational heat flux accounts for approximately 95%, and vibrational-electronic heat flux accounts for approximately 5%. Under super-catalytic wall conditions, translational-rotational heat flux accounts for approximately 55%, chemical diffusion heat flux accounts for approximately 40%, and vibrational-electronic heat flux accounts for approximately 5%.

[0026] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0028] Figure 1This is a flow chart of the method of the first embodiment.

[0029] Figure 2 Heat flow diagram along the wall of each mode under the working condition of Ma is 30.37.

[0030] Figure 3 Graph showing the ratio of stagnation point heat flux of each mode to total heat flux under two wall conditions. DETAILED DESCRIPTION

[0031] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0032] It should be noted that the terms used herein are for describing particular embodiments only and are not intended to limit the exemplary embodiments according to the present invention.

[0033] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0034] Example 1

[0035] As previously mentioned, when predicting aerodynamic heating of a reentry vehicle, using CFD methods or engineering correlations can only calculate the total convective heat flux. The heat flux corresponding to different internal energy modes under the effects of thermochemical nonequilibrium and the chemical diffusion heat cannot be separately extracted. Extracting the sub-modal heat flux and chemical diffusion heat is crucial for further understanding thermochemical nonequilibrium effects, clarifying the heat flux composition, and focusing on the heat fluxes that contribute the most.

[0036] Based on this, this embodiment discloses a method for predicting submodal heat flow in hypersonic thermochemical non-equilibrium flow.

[0037] like Figure 1 As shown, the hypersonic thermochemical non-equilibrium flow sub-modal heat flow prediction method includes the following steps:

[0038] Construct the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation;

[0039] Characterize the thermochemical non-equilibrium effects in hypersonic flow fields based on vibration-electron energy source terms and chemical reaction source terms;

[0040] Based on the transport model, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient and component viscosity coefficient corresponding to the two-temperature model are obtained;

[0041] The closed NS equations are iteratively solved until convergence. According to Fourier's law, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity and component mass diffusion coefficient are combined to obtain the translational-rotational and vibrational-electronic modal heat flux densities corresponding to the translational-rotational and vibrational-electronic temperatures, and the chemical diffusion heat flux density is also obtained.

[0042] The total heat flux density is obtained by adding the translational-rotational modal heat flux density, the vibrational-electronic modal heat flux density and the chemical diffusion heat flux density.

[0043] The specific technical solutions are as follows:

[0044] ①Nano-Sigmoid equations

[0045] The mathematical model of this method uses the basic equations of hypersonic thermochemical non-equilibrium flow, in which the conservation equations of mass, momentum, total energy and vibration electron energy are as follows in the Cartesian coordinate system:

[0046]

[0047] Where t is time; x i is the coordinate in the i direction; u i is the velocity in the i direction; N s represents the total number of components; J s,j is the mass diffusion flux of component s in direction j; ρ s ,ω s , h s and e ve,s are the density, mass generation rate per unit volume, enthalpy, and vibrational-electronic energy of the s component; ρ, p, and τ ij is the total density, total pressure and viscous shear stress; e, h and e ve is the total energy, total enthalpy and vibration-electronic energy; q j and q ve,j is the total heat flow and vibration-electron heat flow, ω ve is the vibration-electronic energy source term.

[0048] ②Transport model

[0049] In this method, air is considered as a chemical reaction gas mixture. The viscosity coefficient of each component s is obtained by the Blottner fitting formula:

[0050] μ s =0.1exp[A s (lnT) 2 +B s lnT+C s ] (5)

[0051] Among them A s , Bs and C s is the fitting coefficient. When calculating the viscosity coefficient of free electrons, the translation-rotation temperature T in Equation (5) should be replaced by the vibration-electronic temperature T ve The thermal conductivity corresponding to the multiple internal energy modes of each component is calculated using the Eucken relation:

[0052]

[0053] k ves =μ s C V,vs +μ s C V,es (7)

[0054] Among them C V,ts , C V,rs , C V,vs and C V,es are the constant volume specific heat under translation, rotation, vibration and electronic modes respectively; μ s is the viscosity coefficient of the s component in the air; k trs is the thermal conductivity of the s component in air under the translational-rotational energy mode; k ves is the thermal conductivity of the s component in air in the vibration-electronic energy mode.

[0055] The total viscosity coefficient and thermal conductivity were calculated using Wilke's semi-empirical formula.

[0056] The total viscosity coefficient is:

[0057]

[0058] Among them, M s 、X s and Φ s are the molar mass, mole fraction and partition function of component s respectively; μ r and M r is the viscosity coefficient and molar mass of the r component.

[0059] The total thermal conductivity corresponding to different modes is calculated as follows:

[0060]

[0061] Among them, k tr is the total thermal conductivity of the translational-rotational energy mode; k ve is the total thermal conductivity of the vibrational-electronic energy mode.

[0062] The equivalent mass diffusion coefficient of component s is given by the CLN (Constant Lewis Number) model:

[0063]

[0064] Where Le is the Lewis number, which is 1.4 in this method; C p,tr is the total translational-rotational constant-pressure specific heat.

[0065] ③ Heat flow identification of different aerodynamic heating modes

[0066] According to Fourier's law, the translational-rotational heat flow and the vibrational-electronic heat flow are calculated as follows:

[0067]

[0068] The calculation formula for chemical diffusion heat flux is as follows:

[0069]

[0070] The total heat flux density is calculated as follows:

[0071] q cw =q tw +q vw +q dw (16)

[0072] Among them, k tr and k ve is the total thermal conductivity corresponding to the translation-rotation energy mode and the vibration-electronic energy mode; Y s is the mass fraction of the s component, n represents the wall normal; T tr is the translation-rotation temperature; T ve is the vibrational-electronic temperature.

[0073] ④ Solver

[0074] PHAROS (Parallel Hypersonic Aerothermodynamics and Radiation Optimized Solver) is a multi-block parallel solver for hypersonic non-equilibrium flows using the finite volume method. It computes the inviscid flux using a modified Steger-Warming scheme, achieving second-order accuracy using MUSCL interpolation. The viscous flux discretization scheme uses second-order central differences. Time marching is performed using linear relaxation iterations.

[0075] PHAROS has been successfully used to study various hypersonic aerodynamic problems, such as RAM-C, FIRE II, Mars Pathfinder, and AS-202.

[0076] Furthermore: Based on the vibration-electronic energy source term, chemical reaction source term, and supplementary state equations and thermodynamic relations, the NS equations are combined and iteratively solved.

[0077] in:

[0078] Equation of state:

[0079] To account for the equation of state of a multicomponent chemical reaction, the first term on the right is the sum of the partial pressures of the components obtained from Dalton's law of partial pressures, and the second term is the electron pressure of the free electrons in the gas component, where R is the universal gas constant, R = 8.314 J / (mol·K):

[0080]

[0081] Thermodynamic relationship:

[0082] The high temperatures in hypersonic flow fields excite vibrations and electronic energy modes in atmospheric components, causing the specific heat ratio γ to no longer be constant. Simultaneously, the relationship between internal energy or enthalpy and temperature is no longer linear. The following equation uses the kinetic theory model to give the relationship between internal energy and temperature under thermodynamic non-equilibrium conditions:

[0083]

[0084] Among them, e and e tr 、e ve They are the total specific energy of the mixed gas, the total specific translational-rotational energy, and the total specific vibrational-electronic energy.

[0085]

[0086] where e trs is the component molar translational kinetic energy e ts , molar rotational energy e rs , molar zero-point enthalpy h 0s sum:

[0087] e trs =e ts +e rs +h 0s (20)

[0088]

[0089] Where mon. represents a monatomic molecule or ion, and dia. represents a diatomic molecule or ion. The total specific vibration-electronic energy of the mixed gas is e ve have

[0090] e ve =e v +e e (twenty three)

[0091] The total specific vibration energy of the mixed gas is e v

[0092]

[0093] The molar vibration energy e of the sth component vs

[0094]

[0095] where θ vs is the vibration characteristic temperature of component s. The total specific electron energy of the mixed gas is e e

[0096]

[0097]

[0098] For the non-free electron components, e es is the molar electron binding energy of component s, which is solved by equation (27), where θ es is the electronic characteristic temperature, g0 and g1 are the degeneracy of the ground state and the first excited state of the electronic energy level of the s component respectively; for the free electron component, e ee is the free electron translational energy, e ee Solve it using formula (28).

[0099] In summary, from h = e + p / ρ, the molar absolute enthalpy of component s is given by formula (29), and the electronic enthalpy is given by formula (30):

[0100]

[0101] Assuming that each component of the flow field satisfies the complete gas state equation, the translational molar constant volume heat capacity C of component s is V,ts , Rotational molar heat capacity at constant volume C V,rs , vibrational molar heat capacity at constant volume C V,vs 、Electron molar heat capacity at constant volume C V,es They are respectively:

[0102]

[0103] C V,rs =R,s=dia. (32)

[0104]

[0105] Therefore, the translational-rotational constant volume specific heat capacity C of the mixed gas is V,tr , vibration constant volume specific heat capacity C V,v 、Electronic constant volume specific heat C V,e , total specific heat capacity C V They are:

[0106]

[0107] C V =C V,tr +C V,ve (37)

[0108] The relationship between the total specific heat capacity at constant pressure and the total specific heat capacity at constant volume is as follows, where M is the equivalent molecular molar mass:

[0109]

[0110] Chemical reactions generate source terms:

[0111] Formula (40) is the chemical reaction equation of each component, where A j is the molecular formula of component j, N represents the forward and reverse stoichiometric coefficients of the rth reaction of component j, respectively. r represents the total number of chemical reactions. The chemical reaction rate of the rth reaction is obtained by formula (41), where k fr 、k br is the forward and reverse reaction rate coefficient, which can be calculated as in formula (42), where A r 、B r 、C r is the fitting coefficient, T c To control the temperature.

[0112] In summary, the chemical reaction generation source term of component s is obtained by formula (2.44):

[0113]

[0114]

[0115] Vibration energy source term:

[0116] The three terms on the right side of Equation (44) represent the energy exchange between the translational energy mode and the vibrational energy mode, and the vibrational energy loss caused by molecular dissociation and atomic recombination, respectively. τ vs are the molar vibration energy and vibration-translation relaxation time of component s calculated using translation temperature, τ es The molar vibration energy and electron-vibration relaxation time of component s are calculated using the electron temperature. s is the vibrational dissociation energy, c vs is the proportional coefficient, which is 1.

[0117]

[0118] Electronic energy source term:

[0119] Equation (46) is the expression of the electron energy source term. The three terms on the right side are the energy exchange between heavy particles and electron translational energy modes, the electron energy loss caused by forced ionization reaction, and the effect of radiation on electron energy. es represents the effective collision frequency between electrons and component s, I O , I N are the molar first ionization energies of O and N atoms, I O =1.3×10 6 J / mol, I N =1.4×10 6 J / mol,R O 、R N They represent the forward reaction rates of forced ionization, and the two reactions are shown in Equations (47) and (48).

[0120]

[0121]

[0122] Vibrational electron energy source term:

[0123] ω ve =ω v +ω e (49)

[0124] Coupling of chemical non-equilibrium and thermodynamic non-equilibrium effects:

[0125] Chemical non-equilibrium and thermodynamic non-equilibrium in the flow field will interact with each other. In the numerical calculation process, the temperature T can be controlled. c To describe the effect of thermodynamic non-equilibrium process on the chemical reaction between particles in the flow field, this paper adopts Park two-temperature model, where a c 、b c The value of varies depending on the type of chemical reaction

[0126]

[0127] exist Figure 2 and Figure 3 In, Q cw is the total heat flow, Q tw , Q vw and Q dw are the translational-rotational modal heat flow, vibrational-electronic modal heat flow and chemical diffusion heat flow, respectively; St, Ma and Re are the Stanton number, Mach number and Reynolds number, respectively; ncw (non-catalytic wall) and scw (super-catalytic wall) represent the completely non-catalytic wall boundary conditions and super-catalytic wall boundary conditions, respectively.

[0128] Figure 2 The figure shows the heat flow along the wall in each mode under the working condition of Ma 30.37. Figure 2 As shown, the total heat flux, translational-rotational modal heat flux, and vibrational-electronic modal heat flux under the completely non-catalytic wall boundary condition (ncw); and the total heat flux, translational-rotational modal heat flux, vibrational-electronic modal heat flux, and chemical diffusion heat flux under the super-catalytic wall boundary condition (scw) are shown.

[0129] Figure 3 The following shows the ratio of the stagnation point heat flux of each mode to the total heat flux under two wall conditions. Figure 3 As shown, St tw / St cw St represents the ratio of translational-rotational modal heat flux to total heat flux; vw / St cw St represents the ratio of vibration-electronic mode heat flow to total heat flow; dw / St cw It represents the ratio of chemical diffusion heat flow to total heat flow.

[0130] pass Figure 2 and Figure 3 By analyzing the data from the experiment, we found the distribution of heat flux in each mode. Under non-catalytic conditions, the translational-rotational heat flux accounts for about 95%, and the vibrational-electronic heat flux accounts for about 5%. Under supercatalytic wall conditions, the translational-rotational heat flux accounts for about 55%, the chemical diffusion heat flux accounts for about 40%, and the vibrational-electronic heat flux accounts for about 5%.

[0131] Example 2

[0132] This embodiment discloses a hypersonic thermochemical non-equilibrium flow sub-modal heat flow prediction system.

[0133] A hypersonic thermochemical non-equilibrium flow submodal heat flow prediction system is characterized by comprising:

[0134] The NS equations building module is configured to: build the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation;

[0135] The source term module is configured to characterize the thermochemical non-equilibrium effects in the hypersonic flow field based on the vibration-electron energy source term and the chemical reaction source term;

[0136] The transport property calculation module is configured to: obtain the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient, and component viscosity coefficient corresponding to the two-temperature model based on the transport model;

[0137] The prediction and solution module is configured to iteratively solve the closed NS equations until convergence, and obtain the translational-rotational modal heat flux density and vibrational-electronic modal heat flux density corresponding to the translational-rotational temperature and vibrational-electronic temperature according to Fourier's law by combining the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, and component mass diffusion coefficient, and simultaneously obtain the chemical diffusion heat flux density;

[0138] The summing module is configured to sum the translation-rotational modal heat flux density, the vibration-electronic modal heat flux density, and the chemical diffusion heat flux density to obtain a total heat flux density.

[0139] Example 3

[0140] The purpose of this embodiment is to provide a computer-readable storage medium.

[0141] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the hypersonic thermochemical non-equilibrium flow sub-modal heat flow prediction method as described in Example 1 of the present disclosure.

[0142] Example 4

[0143] The purpose of this embodiment is to provide an electronic device.

[0144] An electronic device includes a memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the hypersonic thermochemical non-equilibrium flow submodal heat flow prediction method as described in Example 1 of the present disclosure are implemented.

[0145] The steps involved in the apparatuses of Examples 2, 3, and 4 above correspond to those of Method Example 1. For detailed implementations, please refer to the relevant description of Example 1. The term "computer-readable storage medium" should be understood to mean a single medium or multiple media containing one or more instruction sets; it should also be understood to include any medium capable of storing, encoding, or carrying an instruction set for execution by a processor and causing the processor to perform any method of the present invention.

[0146] Those skilled in the art will appreciate that the modules or steps of the present invention described above can be implemented using a general-purpose computer device. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. Alternatively, they can be fabricated into separate integrated circuit modules, or multiple modules or steps can be fabricated into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0147] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without any creative work are still within the scope of protection of the present invention.

Claims

1. A method for predicting the modal heat flow of hypersonic thermochemical non-equilibrium flow, characterized by: The following steps are involved: Construct the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation; Characterize the thermochemical non-equilibrium effects in hypersonic flow fields based on vibration-electron energy source terms and chemical reaction source terms; Based on the transport model, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient, and component viscosity coefficient corresponding to the two-temperature model are obtained, including: The components were obtained based on the Blottner fitting formula. s The viscosity coefficient is obtained, and then the components under the translation-rotation energy mode and vibration-electronic energy mode are obtained. s Thermal conductivity; According to Wilke's semi-empirical formula, the components of the translational-rotational energy mode and the vibrational-electronic energy mode are combined. s The thermal conductivity of the two-temperature model is obtained by the translational-rotational thermal conductivity and the vibrational-electronic thermal conductivity. Translational-rotational thermal conductivity and vibrational-electronic thermal conductivity are calculated as follows: ； ； in, s Indicates components; X s and Φ s They are s Mole fractions and partition functions of components; is the total number of components; is the component under the translation-rotation energy mode s Thermal conductivity; is the translational-rotational thermal conductivity; is the component under the vibration-electronic energy mode s Thermal conductivity; is the vibration-electronic thermal conductivity; The closed NS equations are iteratively solved until convergence. According to Fourier's law, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity and component mass diffusion coefficient are combined to obtain the translational-rotational modal heat flux density and vibrational-electronic modal heat flux density corresponding to the translational-rotational temperature and vibrational-electronic temperature. At the same time, the chemical diffusion heat flux density is obtained. The calculation formulas are: ； ； ； in, is the translational-rotational heat flux density; is the translational-rotational temperature; represents the wall normal; is the translational-rotational thermal conductivity; is the vibration-electron heat flux density; is the vibration-electronic temperature; is the vibration-electronic thermal conductivity; is the chemical diffusion heat flux; is the total number of components; is the total density of air; For components s The equivalent mass diffusion coefficient of For the air s enthalpy of the components; for r molar mass of the components; for s Mass fraction of components; The total heat flux density is obtained by adding the translational-rotational modal heat flux density, the vibrational-electronic modal heat flux density and the chemical diffusion heat flux density.

2. The hypersonic thermochemical non-equilibrium flow partial modal heat flow prediction method according to claim 1, characterized in that: The NS equations are obtained based on a two-temperature model and a multi-component chemical kinetic model; wherein the two-temperature model is: The translational energy mode and rotational energy mode of each atmospheric component are calculated using the translation-rotational temperature T tr The vibrational energy mode and the electronic energy mode are expressed by the vibration-electronic temperature T ve express.

3. The hypersonic thermochemical non-equilibrium flow partial modal heat flow prediction method according to claim 1, characterized in that: Based on the CLN model, the translational-rotational thermal conductivity is obtained. , calculate the component mass diffusion coefficient of each component in the air.

4. The hypersonic thermochemical non-equilibrium flow partial modal heat flow prediction method according to claim 1, characterized in that: Based on the vibration-electronic energy source term, chemical reaction source term, and supplementary state equations and thermodynamic relations, the NS equations are combined and solved iteratively.

5. Hypersonic thermochemical non-equilibrium flow modal heat flow prediction system, characterized by: include: The NS equations building module is configured to: build the NS equations, including the component mass conservation equation, the total momentum conservation equation, the total energy conservation equation, and the vibration electron energy equation; The source term module is configured to characterize the thermochemical non-equilibrium effects in the hypersonic flow field based on the vibration-electron energy source term and the chemical reaction source term; The transport property calculation module is configured to obtain the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity, component mass diffusion coefficient, and component viscosity coefficient corresponding to the two-temperature model based on the transport model, specifically including: The components were obtained based on the Blottner fitting formula. s The viscosity coefficient is obtained, and then the components under the translation-rotation energy mode and vibration-electronic energy mode are obtained. s Thermal conductivity; According to Wilke's semi-empirical formula, the components of the translational-rotational energy mode and the vibrational-electronic energy mode are combined. s The thermal conductivity of the two-temperature model is obtained by the translational-rotational thermal conductivity and the vibrational-electronic thermal conductivity. Translational-rotational thermal conductivity and vibrational-electronic thermal conductivity are calculated as follows: ； ； in, s Indicates components; X s and Φ s They are s Mole fractions and partition functions of components; is the total number of components; is the component under the translation-rotation energy mode s Thermal conductivity; is the translational-rotational thermal conductivity; is the component under the vibration-electronic energy mode s Thermal conductivity; is the vibration-electronic thermal conductivity; The prediction and solution module is configured to iteratively solve the closed NS equations until convergence. According to Fourier's law, the translational-rotational thermal conductivity, vibrational-electronic thermal conductivity and component mass diffusion coefficient are combined to obtain the translational-rotational modal heat flux density and vibrational-electronic modal heat flux density corresponding to the translational-rotational temperature and vibrational-electronic temperature. At the same time, the chemical diffusion heat flux density is obtained. The calculation formulas are: ； ； ； in, is the translational-rotational heat flux density; is the translational-rotational temperature; represents the wall normal; is the translational-rotational thermal conductivity; is the vibration-electron heat flux density; is the vibration-electronic temperature; is the vibration-electronic thermal conductivity; is the chemical diffusion heat flux; is the total number of components; is the total density of air; For components s The equivalent mass diffusion coefficient of For the air s enthalpy of the components; for r molar mass of the components; for s Mass fraction of components; The summing module is configured to sum the translation-rotational modal heat flux density, the vibration-electronic modal heat flux density, and the chemical diffusion heat flux density to obtain a total heat flux density.

6. A computer-readable storage medium having a program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method for predicting submodal heat flow of hypersonic thermochemical non-equilibrium flow are implemented.

7. An electronic device comprising a memory, a processor, and a program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the method for predicting submodal heat flow of hypersonic thermochemical non-equilibrium flow are implemented as described in any one of claims 1 to 4.

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