Method and device for calculating the electronic energy level distribution of gas molecules

Abstract

This invention provides a method and apparatus for calculating the electronic energy level distribution of gas molecules. The method includes: determining macroscopic parameters of a target gas molecule in a one-dimensional flow field; the macroscopic parameters including the number density of the target gas molecule at each node in the one-dimensional flow field; calculating the number density of all electronic energy levels of the target gas molecule at an initial node in the one-dimensional flow field using the Boltzmann distribution formula based on the number density of the target gas molecule; determining the number density of all electronic energy levels at the next node of the initial node based on the number density of all electronic energy levels at the initial node, the convection term of the initial node, and the excitation term of the initial node; and using the next node of the initial node as a new initial node until the electronic energy level distribution of the target gas molecule in the one-dimensional flow field is obtained. This method not only reduces the computational load but also ensures the accuracy of the calculation of the electronic energy level distribution of gas molecules in a thermodynamically non-equilibrium hypersonic flow field.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of electron energy level distribution, and in particular to a method and device for calculating the electron energy level distribution of gas molecules. Background Art

[0002] When the flight altitude is high (generally greater than 30km) and the flight speed is high (generally greater than 6Ma), the flow field formed around the aircraft will be in a thermodynamic non-equilibrium state. The so-called thermodynamic non-equilibrium state means that when the flow field pressure is low and the flow velocity is fast, the gas molecules in the flow field do not collide sufficiently, resulting in the vibration and electron energy of these molecules not being fully exchanged, resulting in the distribution of molecular energy levels in the flow field not reaching the local thermodynamic equilibrium state, that is, not reaching the Boltzmann distribution. The flow, heat transfer and optical radiation properties of the flow field in a thermodynamic non-equilibrium state will be significantly different from those in a thermodynamic equilibrium state. Therefore, accurate simulation of the electronic energy level distribution of gas molecules in such hypersonic flow fields is the primary basis for predicting flow field distribution, aerodynamic heating and optical radiation. At the same time, since the energy level distribution in the thermodynamic non-equilibrium state is related to many microscopic physical processes, this problem has also become a key issue restricting the numerical simulation of thermal and optical effects in hypersonic flow fields.

[0003] The existing methods for calculating the electronic energy level distribution of gas molecules in thermodynamic non-equilibrium hypersonic flow fields mainly include: multi-temperature method (muti-temperature), quasi-steady-state method (quasi-steady-state), and state-to-state method (state-to-state). Among them, the multi-temperature method assumes that the gas in the flow field satisfies its own Boltzmann distribution in the four degrees of freedom of rotation, vibration, translation and electron respectively. It is the simplest method, but the simulation accuracy is the lowest. The quasi-steady-state method ignores the influence of the excitation process in the flow on the energy level distribution, and assumes that the excitation term in the electronic energy level distribution of gas molecules at various locations in the flow field is 0. This method is simple to calculate and has high accuracy when the quasi-steady-state assumption is met, but it is completely inapplicable when the assumption is not met. The state-to-state method treats each electronic state of the molecule as a completely independent component, and couples the flow to calculate the electronic energy level distribution at various locations in the flow field according to the method of chemical reaction flow. This method has high calculation accuracy, but the amount of calculation is too huge and it is difficult to meet the requirements of engineering applicability. Summary of the invention

[0004] Based on the problems that the multi-temperature method has low calculation accuracy, the quasi-steady-state method has limited application scope, and the state-to-state method has large calculation amount in the existing calculation methods of the electron energy level distribution of gas molecules in the thermodynamic non-equilibrium hypersonic flow field, the embodiments of the present invention provide a method and device for calculating the electron energy level distribution, which can greatly reduce the calculation amount while ensuring the calculation accuracy of the electron energy level distribution of gas molecules in the thermodynamic non-equilibrium hypersonic flow field.

[0005] In a first aspect, an embodiment of the present invention provides a method for calculating the electronic energy level distribution of a gas molecule, comprising:

[0006] Determine the macroscopic parameters of the target gas molecules in the one-dimensional flow field; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macroscopic parameters include the flow velocity, temperature and number density of the target gas molecules at each node in the one-dimensional flow field;

[0007] According to the number density of the target gas molecules, the number density of all electron energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field is calculated using the Boltzmann distribution formula;

[0008] Determining a convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node, and the flow velocity of a node next to the initial node;

[0009] Determining an excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes;

[0010] Determine the number density of all electronic energy levels of the next node of the initial node according to the number density of all electronic energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node;

[0011] The next node of the initial node is used as a new initial node, and the convection item of determining the initial node is executed in a jump manner until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

[0012] Preferably, the Boltzmann distribution formula is:

[0013]

[0014] in, is the number density of the i-th electronic energy level of the target gas molecule at the initial node of the one-dimensional flow field; N 0 is the molecular number density of the target gas molecules at the initial node; T 0 is the temperature of the initial node; g i is the degeneracy of the target gas molecule at the i-th electronic energy level of the initial node; E i is the energy item value of the i-th electronic energy level of the target gas molecule at the initial node; c is the preset radiation constant; and m is the number of electronic energy levels of the target gas molecule.

[0015] Preferably, the convection term of the initial node is calculated by the following formula:

[0016]

[0017] in, is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; u 0 is the flow rate of the initial node; u 1 is the flow rate of the next node of the initial node.

[0018] Preferably, the excitation term of the initial node is calculated by the following formula:

[0019]

[0020] in, is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node; dx is the distance between adjacent nodes; u 0 is the flow rate of the initial node, Related to the temperature of the initial node.

[0021] Preferably, the macroscopic parameters also include the number density of free electrons and the number density of heavy particles at each node;

[0022] The energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node is calculated by the following formula:

[0023]

[0024] in, is the number density of free electrons at the initial node; is the number density of heavy particles at the initial node; is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to collision with free electrons at the initial node; K is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to the collision with the heavy particles at the initial node; 0 (c,i) is the recombination rate of the target gas molecules at the initial node; K 0 (i,c) is the ionization rate of the target gas molecule at the initial node; A 0 (j,i) is the rate at which the target gas molecule spontaneously radiates from the jth energy level to the ith energy level at the initial node; m is the number of electron energy levels of the target gas molecule; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; is the number density of ions generated after the target gas molecules are ionized at the initial node; is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the free electron at the initial node; A is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the heavy particles at the initial node; 0 (i, j) is the rate at which the target gas molecule spontaneously radiates from the i-th energy level to the j-th energy level at the initial node; is the number density of the jth electronic energy level of the target gas molecule at the initial node.

[0025] Preferably, the number density of all electronic energy levels of the target gas molecule at the next node of the initial node is calculated by the following formula:

[0026]

[0027] in, is the number density of the i-th electronic energy level of the target gas molecule at the next node of the initial node; is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the i-th electronic energy level of the target gas molecule at the initial node.

[0028] Preferably, the macroscopic parameters of the one-dimensional flow field are obtained by simulation using CFD software.

[0029] In a second aspect, an embodiment of the present invention further provides a device for calculating the electronic energy level distribution of gas molecules, comprising:

[0030] A macro parameter determination module, used to determine the macro parameters of the target gas molecules in a one-dimensional flow field; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macro parameters include the flow velocity, temperature of each node in the one-dimensional flow field and the number density of the target gas molecules;

[0031] A first calculation module, used for calculating the number density of all electronic energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field using the Boltzmann distribution formula according to the number density of the target gas molecules;

[0032] A convection term determination module, used to determine the convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node and the flow velocity of the next node of the initial node;

[0033] An excitation item determination module, used to determine the excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes;

[0034] A second calculation module, used to determine the number density of all electronic energy levels of the next node of the initial node according to the number density of all electronic energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node;

[0035] A jump execution module is used to take the next node of the initial node as a new initial node, and jump to execute the convection item determined for the initial node until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

[0036] In a third aspect, an embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method described in any embodiment of this specification is implemented.

[0037] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute the method described in any embodiment of this specification.

[0038] The embodiment of the present invention provides a method and device for calculating the electronic energy level distribution of gas molecules, which obtains the flow field macroscopic distribution of the target gas molecules by determining the macroscopic parameters of the target gas molecules in the one-dimensional flow field, and then calculates the molecular electronic energy level distribution of the target gas molecules in the entire one-dimensional flow field according to the number density of all electronic energy levels of the initial nodes in the one-dimensional flow field, completely decouples the flow field distribution calculation from the electronic energy level calculation, and introduces convection terms and excitation terms when calculating the electronic energy level distribution. Therefore, this solution can not only greatly reduce the amount of calculation, but also ensure the calculation accuracy of the electronic energy level distribution of gas molecules in a thermodynamic non-equilibrium hypersonic flow field. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1It is a flow chart of a method for calculating the electronic energy level distribution of a gas molecule provided by one embodiment of the present invention;

[0041] Figure 2 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0042] Figure 3 It is a structural diagram of a device for calculating the electronic energy level distribution of gas molecules provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] As mentioned above, the existing quasi-steady-state method assumes that the energy level change is much smaller than the rate of various excitation processes. Therefore, it assumes that the excitation term in the electronic energy level distribution of gas molecules at various locations in the flow field is 0, ignoring the influence of the excitation process in the flow on the energy level distribution. It is completely inapplicable in flow fields that do not meet the assumption; while the state-to-state method treats each electronic energy level of the molecule as a completely independent component, and couples the flow process according to the method of chemical reaction flow to calculate the electronic energy level distribution at various locations in the flow field. This method has high calculation accuracy, but the amount of calculation is too large. Therefore, it is considered to independently calculate the macroscopic distribution of the target gas molecules in the one-dimensional flow field, obtain the flow velocity, temperature and number density of the target gas molecules at each node of the flow field, and completely decouple the flow field distribution calculation from the subsequent electronic energy level calculation. Compared with the state-to-state method, the amount of calculation is greatly reduced. At the same time, the convection term and the excitation term are introduced when calculating the electronic energy level distribution. Compared with the quasi-steady-state method, it is applicable to all hypersonic flow fields, and the calculation accuracy of the electronic energy level distribution of gas molecules in thermodynamic non-equilibrium hypersonic flow fields is guaranteed.

[0045] The specific implementation of the above concept is described below.

[0046] Please refer to Figure 1 , an embodiment of the present invention provides a method for calculating the electronic energy level distribution of gas molecules, the method comprising:

[0047] Step 100, determining the macroscopic parameters of the target gas molecules in a one-dimensional flow field; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macroscopic parameters include the flow velocity, temperature of each node in the one-dimensional flow field and the number density of the target gas molecules.

[0048] Step 102: Calculate the number density of all electron energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field using the Boltzmann distribution formula according to the number density of the target gas molecules.

[0049] Step 104 , determining the convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node and the flow velocity of the next node of the initial node.

[0050] Step 106: determining an excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes.

[0051] Step 108, determining the number density of all electron energy levels of the next node of the initial node according to the number density of all electron energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node.

[0052] Step 110: Taking the next node of the initial node as a new initial node, and jumping to execute the convection term of determining the initial node, until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

[0053] In the embodiment of the present invention, the flow field macroscopic distribution of the target gas molecules is obtained by determining the macroscopic parameters of the target gas molecules in the one-dimensional flow field, and then the molecular electronic energy level distribution of the target gas molecules in the entire one-dimensional flow field is calculated according to the number density of all electronic energy levels of the initial nodes in the one-dimensional flow field, and the flow field distribution calculation is completely decoupled from the electronic energy level calculation, while introducing convection terms and excitation terms when calculating the electronic energy level distribution. Therefore, this scheme can not only greatly reduce the amount of calculation, but also ensure the calculation accuracy of the electronic energy level distribution of gas molecules in the thermodynamic non-equilibrium hypersonic flow field.

[0054] Described below Figure 1 How the various steps are performed.

[0055] First, for step 100, the macroscopic parameters of the target gas molecules in the one-dimensional flow field are determined; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macroscopic parameters include the flow velocity, temperature and number density of the target gas molecules at each node in the one-dimensional flow field.

[0056] In an embodiment of the present invention, in order to reduce the amount of calculation compared to the state-to-state method, it is necessary to completely decouple the distribution of the target gas molecules in the flow field from the calculation of their electronic energy levels. Therefore, it is necessary to first determine the macroscopic parameters of the target gas molecules in the one-dimensional thermodynamic non-equilibrium flow field, and then calculate the electronic energy level distribution of the target gas molecules at each node after knowing the flow velocity, temperature and number density of the target gas molecules at each node in the flow field.

[0057] There are many methods to determine the macroscopic parameters of the target gas molecules in a one-dimensional flow field. In an embodiment of the present invention, the macroscopic parameters of the one-dimensional flow field are simulated by CFD software. The simulated macroscopic parameters include the flow velocity, temperature, pressure, density, number density of the target gas molecules and other parameters of each node in the one-dimensional flow field.

[0058] It should be noted that in practical applications, the complex flow field around a real aircraft is more than one-dimensional. We can first simulate the one-dimensional flow field for analysis and calculation, and then calculate the complex flow field around the real aircraft based on the actual situation.

[0059] Then, for step 102, according to the number density of the target gas molecules, the number density of all electron energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field is calculated using the Boltzmann distribution formula.

[0060] In an embodiment of the present invention, it is assumed that the flow field inlet boundary is in a thermodynamic equilibrium state. Therefore, the number density of all electron energy levels of the target gas molecules at the initial node at the boundary can be calculated using the Boltzmann distribution formula based on the temperature of the initial node determined in step 100 and the number density of the target gas molecules.

[0061] The Boltzmann distribution formula is as follows:

[0062]

[0063] in, is the number density of the i-th electronic energy level of the target gas molecule at the initial node of the one-dimensional flow field; N 0 is the molecular number density of the target gas molecules at the initial node; T 0 is the temperature of the initial node; g i is the degeneracy of the target gas molecule at the i-th electronic energy level of the initial node; E i is the energy item value of the i-th electronic energy level of the target gas molecule at the initial node; c is the preset radiation constant; and m is the number of electronic energy levels of the target gas molecule.

[0064] In the embodiment of the present invention, N 0 and T 0 can be determined from the macroscopic parameters in step 100, g i is the known quantity obtained according to Boltzmann distribution. Similarly, E i and c are also known quantities. m can be determined according to the type of target gas, so it can be calculated

[0065] It can be understood that the number of electron energy levels of the target gas molecules can be determined according to the type of the target gas, and the number density of all electron energy levels of the target gas molecules at the initial node can be calculated according to the Boltzmann distribution formula.

[0066] Next, for step 104, the convection term of the initial node is determined according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node, and the flow velocity of the next node of the initial node.

[0067] In order to ensure the calculation accuracy, the convection term of the initial node is introduced when calculating the number density of all electron energy levels of the next node of the initial node. The convection term of the initial node can be calculated according to the number density of all electron energy levels of the initial node obtained in step 102 and the flow rate between the initial node and its next node determined in step 100.

[0068] Specifically, the convection term of the initial node is calculated by the following formula:

[0069]

[0070] in, is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; u 0 is the flow rate of the initial node; u 1 is the flow rate of the next node of the initial node.

[0071] In an embodiment of the present invention, is the calculation result in step 102, u 0 and u 1 By determining the macro parameters in step 100, it can be calculated that

[0072] It can be understood that the convection term of each electron energy level of the target gas molecule at the initial node is calculated by the above formula.

[0073] Next, for step 106, the excitation item of the initial node is determined according to the temperature of the initial node and the distance between adjacent nodes.

[0074] Similarly, since the quasi-steady state method ignores the influence of the excitation process in the flow on the energy level distribution, resulting in a limited scope of application, the present invention introduces an excitation term. The excitation term of the initial node can be calculated based on the temperature of the initial node determined in step 100 and the preset distance between adjacent nodes of the flow field.

[0075] In one embodiment of the present invention, the excitation item of the initial node may be determined at least through the following steps S1-S2:

[0076] S1, the excitation term of the initial node is calculated by the following formula:

[0077]

[0078] in, is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node; dx is the distance between adjacent nodes; u 0 is the flow rate of the initial node, Related to the temperature of the initial node.

[0079] In the embodiment of the present invention, dx is preset according to the required accuracy, u 0 According to the macro parameter determination in step 100, It needs to be calculated through step S2 to calculate

[0080] It can be understood that calculating the excitation term of the initial node is to calculate the excitation term of each electron energy level of the target gas molecule at the initial node.

[0081] However, in this step, the energy level excitation rate of each electronic energy level of the target gas molecule at the initial node is also related to the temperature of the initial node. Therefore, to calculate the excitation term of the initial node, it is also necessary to calculate the energy level excitation rate of each electronic energy level of the target gas molecule at the initial node based on the temperature of the initial node.

[0082] S2, the macroscopic parameters also include the number density of free electrons and the number density of heavy particles at each node; the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node is calculated by the following formula:

[0083]

[0084] in, is the number density of free electrons at the initial node; is the number density of heavy particles at the initial node; is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to collision with free electrons at the initial node; K is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to the collision with the heavy particles at the initial node; 0(c,i) is the recombination rate of the target gas molecules at the initial node; K 0 (i,c) is the ionization rate of the target gas molecule at the initial node; A 0 (j,i) is the rate at which the target gas molecule spontaneously radiates from the jth energy level to the ith energy level at the initial node; m is the number of electron energy levels of the target gas molecule; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; is the number density of ions generated after the target gas molecules are ionized at the initial node; is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the free electron at the initial node; A is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the heavy particles at the initial node; 0 (i, j) is the rate at which the target gas molecule spontaneously radiates from the i-th energy level to the j-th energy level at the initial node; is the number density of the jth electronic energy level of the target gas molecule at the initial node.

[0085] In an embodiment of the present invention, and Determined according to the macro parameters in step 100; can be determined based on the temperature of the initial node, which is a known quantity. Similarly, K 0 (c,i),K 0 (i,c), Also a known quantity; A 0 (j,i),A 0 (i,j), is also a known quantity; and is the calculation result in step 102, so it can be calculated that Will Substituting into S1, we can get

[0086] In the embodiment of the present invention, the energy level excitation rate of each electronic energy level of the target gas molecule at the initial node obtained according to the calculation formula in step S2 is brought into step S1 to obtain the excitation term of the initial node.

[0087] Next, for step 108, the number density of all electron energy levels of the next node of the initial node is determined according to the number density of all electron energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node.

[0088] In an embodiment of the present invention, the number density of all electron energy levels of the next node of the initial node can be calculated based on the number density of all electron energy levels of the initial node obtained in step 102, the convection term of the initial node obtained in step 104, and the excitation term of the initial node obtained in step 106.

[0089] Specifically, the number density of all electronic energy levels of the target gas molecule at the next node of the initial node is calculated by the following formula:

[0090]

[0091] in, is the number density of the i-th electronic energy level of the target gas molecule at the next node of the initial node; is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the i-th electronic energy level of the target gas molecule at the initial node.

[0092] In an embodiment of the present invention, is the calculation result of step 104, is the calculation result of step 106, is the calculation result of step 102, so it can be calculated that

[0093] It should be noted that in order to clearly distinguish it from the existing quasi-steady-state method and state-to-state method, the convection term of the initial node in step 104 and the excitation term of the initial node in step 106 are calculated respectively, and then the number density of all electron energy levels of the next node of the initial node is calculated through step 108.

[0094] In the embodiment of the present invention, the number density of all electronic energy levels of the next node of the initial node can be directly calculated according to the following formula:

[0095]

[0096] in, is the number density of the i-th electronic energy level of the target gas molecule at the next node of the initial node; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; u 0 is the flow rate of the initial node; u 1 is the flow rate of the next node of the initial node; is the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node; dx is the distance between adjacent nodes.

[0097] In the embodiment of the present invention, u 0 and u 1 Determined by the macro parameters in step 100, dx is preset according to the required accuracy, is the calculation result of step S2, is the calculation result of step 102, so it can be calculated that

[0098] In an embodiment of the present invention, the energy level excitation rate of each electronic energy level of the target gas molecule at the initial node obtained by the calculation formula in step S2 can be substituted into this formula to obtain the number density of all electronic energy levels of the next node of the initial node.

[0099] Finally, for step 110, the next node of the initial node is used as a new initial node, and the convection term of determining the initial node is jumped to execute until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

[0100] In the embodiment of the present invention, in step 102, the number density of all electron energy levels of the target gas molecules at the initial node at the flow field inlet boundary is calculated using the Boltzmann distribution formula. Steps 104-108 are executed cyclically along the flow velocity direction according to the preset flow field nodes, and the number density of all the electron energy levels of the target gas molecules at each node is recursively calculated one by one. The electronic energy level distribution of the target gas molecules in the one-dimensional flow field can be obtained.

[0101] It should be noted that in practical applications, the complex flow field around a real aircraft is more than one-dimensional and contains more than one type of gas molecules. Therefore, it is necessary to calculate the molecular electronic energy level distribution of each gas in the complex flow field around a real aircraft separately according to the actual situation.

[0102] like Figure 2 , Figure 3 As shown, an embodiment of the present invention provides a device for calculating the electronic energy level distribution of gas molecules. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 2 As shown, a hardware architecture diagram of a computing device where a computing device for calculating the electronic energy level distribution of gas molecules provided by an embodiment of the present invention is located, except Figure 3 In addition to the processor, memory, network interface, and non-volatile memory shown in the figure, the computing device in which the device is located in the embodiment may also generally include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 3 As shown, as a device in a logical sense, the CPU of the computing device in which it is located reads the corresponding computer program in the non-volatile memory into the memory and runs it. This embodiment provides a computing device for the electronic energy level distribution of gas molecules, including:

[0103] The macro parameter determination module 301 is used to determine the macro parameters of the target gas molecules in the one-dimensional flow field; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macro parameters include the flow velocity, temperature and number density of the target gas molecules at each node in the one-dimensional flow field;

[0104] A first calculation module 302 is used to calculate the number density of all electron energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field using the Boltzmann distribution formula according to the number density of the target gas molecules;

[0105] A convection term determination module 303, configured to determine the convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node and the flow velocity of the next node of the initial node;

[0106] An excitation item determination module 304, configured to determine an excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes;

[0107] A second calculation module 305 is used to determine the number density of all electron energy levels of the next node of the initial node according to the number density of all electron energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node;

[0108] The jump execution module 306 is used to take the next node of the initial node as a new initial node, and jump to execute the convection item determined for the initial node until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

[0109] In one embodiment of the present invention, in the first calculation module 302, the Boltzmann distribution formula is:

[0110]

[0111] in, is the number density of the i-th electronic energy level of the target gas molecule at the initial node of the one-dimensional flow field; N 0 is the molecular number density of the target gas molecules at the initial node; T 0 is the temperature of the initial node; g i is the degeneracy of the target gas molecule at the i-th electronic energy level of the initial node; E iis the energy item value of the i-th electronic energy level of the target gas molecule at the initial node; c is the preset radiation constant; and m is the number of electronic energy levels of the target gas molecule.

[0112] In one embodiment of the present invention, in the convection term determination module 303, the convection term of the initial node is calculated by the following formula:

[0113]

[0114] in, is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; u 0 is the flow rate of the initial node; u 1 is the flow rate of the next node of the initial node.

[0115] In one embodiment of the present invention, in the excitation item determination module 304, the excitation item of the initial node is calculated by the following formula:

[0116]

[0117] in, is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node; dx is the distance between adjacent nodes; u 0 is the flow rate of the initial node, Related to the temperature of the initial node.

[0118] In one embodiment of the present invention, in the macroscopic parameter determination module 301, the macroscopic parameters also include the number density of free electrons and the number density of heavy particles at each node;

[0119] In the excitation term determination module 304, the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node is calculated by the following formula:

[0120]

[0121] in, is the number density of free electrons at the initial node; is the number density of heavy particles at the initial node; is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to collision with free electrons at the initial node; K is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to the collision with the heavy particles at the initial node; 0 (c,i) is the recombination rate of the target gas molecules at the initial node; K 0 (i,c) is the ionization rate of the target gas molecule at the initial node; A 0 (j,i) is the rate at which the target gas molecule spontaneously radiates from the jth energy level to the ith energy level at the initial node; m is the number of electron energy levels of the target gas molecule; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; is the number density of ions generated after the target gas molecules are ionized at the initial node; is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the free electron at the initial node; A is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the heavy particles at the initial node; 0 (i, j) is the rate at which the target gas molecule spontaneously radiates from the i-th energy level to the j-th energy level at the initial node; is the number density of the jth electronic energy level of the target gas molecule at the initial node.

[0122] In one embodiment of the present invention, in the second calculation module 305, the number density of all electronic energy levels of the target gas molecule at the next node of the initial node is calculated by the following formula:

[0123]

[0124] in, is the number density of the i-th electronic energy level of the target gas molecule at the next node of the initial node; is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the i-th electronic energy level of the target gas molecule at the initial node.

[0125] In one embodiment of the present invention, the macroscopic parameters of the one-dimensional flow field in the macroscopic parameter determination module 301 are obtained by simulating with CFD software.

[0126] It is understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a device for calculating the electronic energy level distribution of a gas molecule. In other embodiments of the present invention, a device for calculating the electronic energy level distribution of a gas molecule may include more or fewer components than shown in the figure, or combine certain components, or split certain components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0127] The information interaction, execution process and other contents between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0128] An embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a method for calculating the electronic energy level distribution of a gas molecule in any embodiment of the present invention is implemented.

[0129] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor executes a method for calculating the electronic energy level distribution of a gas molecule in any embodiment of the present invention.

[0130] Specifically, a system or device equipped with a storage medium can be provided, on which software program code that implements the functions of any of the above-mentioned embodiments is stored, and a computer (or CPU or MPU) of the system or device can be enabled to read and execute the program code stored in the storage medium.

[0131] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute a part of the present invention.

[0132] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

[0133] In addition, it should be clear that the functions of any of the above embodiments can be implemented not only by executing the program code read by the computer, but also by enabling an operating system operating on the computer to complete part or all of the actual operations based on instructions from the program code.

[0134] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above-mentioned embodiments.

[0135] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical factors in the process, method, article or device including the elements.

[0136] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0137] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating the electronic energy level distribution of gas molecules, characterized in that: include: Determine the macroscopic parameters of the target gas molecules in the one-dimensional flow field; the one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macroscopic parameters include the flow velocity, temperature and number density of the target gas molecules at each node in the one-dimensional flow field; According to the number density of the target gas molecules, the number density of all electron energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field is calculated using the Boltzmann distribution formula; Determining a convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node, and the flow velocity of a node next to the initial node; Determining an excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes; Determine the number density of all electronic energy levels of the next node of the initial node according to the number density of all electronic energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node; The next node of the initial node is used as a new initial node, and the convection item of determining the initial node is executed in a jump manner until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

2. The method according to claim 1, characterized in that The Boltzmann distribution formula is: in, is the number density of the i-th electronic energy level of the target gas molecule at the initial node of the one-dimensional flow field; N 0 is the molecular number density of the target gas molecules at the initial node; T 0 is the temperature of the initial node; g i is the degeneracy of the target gas molecule at the i-th electronic energy level at the initial node; E i is the energy item value of the i-th electronic energy level of the target gas molecule at the initial node; c is the preset radiation constant; and m is the number of electronic energy levels of the target gas molecule.

3. The method according to claim 1, characterized in that The convection term of the initial node is calculated by the following formula: in, is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; u 0 is the flow rate of the initial node; u 1 is the flow rate of the next node of the initial node.

4. The method according to claim 1, characterized in that: The excitation term of the initial node is calculated by the following formula: in, is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node; dx is the distance between adjacent nodes; u 0 is the flow rate of the initial node, Related to the temperature of the initial node.

5. The method according to claim 4, characterized in that The macroscopic parameters also include the number density of free electrons and the number density of heavy particles at each grid node; The energy level excitation rate of the target gas molecule at the i-th electronic energy level of the initial node is calculated by the following formula: in, is the number density of free electrons at the initial node; is the number density of heavy particles at the initial node; is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to collision with free electrons at the initial node; K is the rate at which the target gas molecule is excited from the jth energy level to the ith energy level due to the collision with the heavy particles at the initial node; 0 (c,i) is the recombination rate of the target gas molecules at the initial node; K 0 (i,c) is the ionization rate of the target gas molecule at the initial node; A 0 (j,i) is the rate at which the target gas molecule spontaneously radiates from the jth energy level to the ith energy level at the initial node; m is the number of electron energy levels of the target gas molecule; is the number density of the target gas molecule at the i-th electronic energy level at the initial node; is the number density of ions generated after the target gas molecules are ionized at the initial node; is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the free electron at the initial node; A is the rate at which the target gas molecule is excited from the i-th energy level to the j-th energy level due to the collision with the heavy particles at the initial node; 0 (i, j) is the rate at which the target gas molecule spontaneously radiates from the i-th energy level to the j-th energy level at the initial node; is the number density of the jth electronic energy level of the target gas molecule at the initial node.

6. The method according to claim 1, characterized in that The number density of all electronic energy levels of the target gas molecule at the next node of the initial node is calculated by the following formula: in, is the number density of the i-th electronic energy level of the target gas molecule at the next node of the initial node; is the convection term of the target gas molecule at the i-th electronic energy level of the initial node; is the excitation term of the target gas molecule at the i-th electronic energy level of the initial node; is the number density of the i-th electronic energy level of the target gas molecule at the initial node.

7. The method according to any one of claims 1 to 6, characterized in that The macroscopic parameters of the one-dimensional flow field are obtained by simulation using CFD software.

8. A device for calculating the electronic energy level distribution of gas molecules, characterized in that: include: A macro parameter determination module is used to determine the macro parameters of the target gas molecules in a one-dimensional flow field; The one-dimensional flow field is in a thermodynamic non-equilibrium state, and the macroscopic parameters include the flow velocity, temperature and number density of the target gas molecules at each node in the one-dimensional flow field; A first calculation module, used for calculating the number density of all electronic energy levels of the target gas molecules at the initial nodes in the one-dimensional flow field using the Boltzmann distribution formula according to the number density of the target gas molecules; A convection term determination module, used to determine the convection term of the initial node according to the number density of all electron energy levels of the initial node, the flow velocity of the initial node and the flow velocity of the next node of the initial node; An excitation item determination module, used to determine the excitation item of the initial node according to the temperature of the initial node and the distance between adjacent nodes; A second calculation module is used to determine the number density of all electronic energy levels of the next node of the initial node according to the number density of all electronic energy levels of the initial node, the convection term of the initial node and the excitation term of the initial node; A jump execution module is used to take the next node of the initial node as a new initial node, and jump to execute the convection item determined for the initial node until the electronic energy level distribution of the target gas molecules in the one-dimensional flow field is obtained.

9. A computing device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method according to any one of claims 1 to 7.

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