A method for determining spacecraft radiation resistance indicators in a comprehensive radiation environment

Abstract

The present invention relates to a method for determining the radiation resistance index of a spacecraft in a comprehensive radiation environment, and belongs to the field of spacecraft technology. At present, the application of space reactors is in its infancy, and the calculation method of its comprehensive radiation environment is not yet mature. There are only calculation methods for natural radiation environment conditions. The present method is applicable to the comprehensive radiation environment of space reactor spacecraft. The total ionization dose suffered by the spacecraft platform is the sum of the total ionization dose caused by the natural radiation environment and the artificial radiation environment; the displacement damage dose suffered by the spacecraft platform is the sum of the displacement damage dose caused by the natural radiation environment and the artificial radiation environment.

Description

Technical Field

[0001] The present invention relates to a method for determining a spacecraft radiation resistance index in a comprehensive radiation environment, and belongs to the technical field of spacecraft. Background Art

[0002] With the development of the space industry, missions such as deep space exploration have placed higher demands on energy supply. The use of space reactors is an inevitable choice. However, space reactors produce high fluences of neutrons and gamma rays. These neutral particles have strong penetrating power and can have more severe radiation effects on individual spacecraft than charged particles such as electrons and protons in the space environment. Traditional calculations of the radiation environment conditions for near-Earth spacecraft only consider the radiation effects of charged particles such as protons, electrons, and heavy ions in the natural radiation environment on the spacecraft. When calculating the radiation environment conditions for space reactor spacecraft, it is necessary to consider not only the radiation effects introduced by the natural radiation environment but also the radiation effects of the space reactor on the spacecraft. The traditional space environment cannot be directly applied and requires corresponding optimization.

[0003] Currently, the application of space reactors is in its infancy, and calculation methods for their integrated radiation environment are immature. Only methods targeting natural radiation environmental conditions exist, such as CN104143012A, "A Method for Identifying Hazards in the Space Radiation Environment," CN104142628A, "Design Method for Space Radiation Environment Reliability Indicators," "Space Radiation Environment Engineering," NASA SP-8116, "NASA Spacecraft Design Guidelines (Environment) Earth Trapped Radiation Belt," AIAA G-083-1999, "Guidelines for Modeling the Earth Trapped Radiation Environment," and ESA PSS-01-609, "Radiation Design Manual." This method is suitable for calculating the integrated radiation environment of space reactor spacecraft.

[0004] The calculation methods for the comprehensive radiation environment are not yet mature, and there are only calculation methods for natural radiation environment conditions. This method is applicable to the calculation of the comprehensive radiation environment (including natural radiation environment and artificial radiation environment) of space reactors and spacecraft. Summary of the Invention

[0005] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and propose a method for determining the radiation resistance index of a spacecraft under a comprehensive radiation environment.

[0006] The technical solution of the present invention is:

[0007] A method for determining a spacecraft's radiation resistance index in a comprehensive radiation environment, wherein the spacecraft's radiation resistance index includes the total ionization dose and displacement damage dose caused by the natural radiation environment, and also includes the total ionization dose and displacement damage dose caused by the reactor radiation environment;

[0008] The method for determining the total ionization dose and displacement damage dose caused by the natural radiation environment is:

[0009] Use radiation environment simulation software to simulate the natural radiation environment and obtain the total ionization dose and displacement damage dose caused by the natural radiation environment;

[0010] The radiation environment simulation software includes: Space radiation, FASTRAD, OMERE, Systema, SPENVIS, etc.

[0011] The input conditions for simulating the natural radiation environment include: the number of six orbits of the spacecraft, the launch time, the mission period, the natural radiation environment simulation model, and the analytical structure model;

[0012] The six orbital parameters of the spacecraft include the semi-major axis a, the eccentricity e, the orbital inclination i, as well as the argument of periapsis ω, the longitude of the ascending node Ω and the true anomaly at launch.

[0013] The natural radiation environment simulation models include: AP8 / AE8, AP9 / AE9, IGE2006, MEOv2, FLUMIC, and NASA's worst energy spectrum. AP8 / AE8 or AP9 / AE9 is usually selected as the simulation model.

[0014] The analytical structural model includes a solid sphere, a spherical shell model, a flat plate model or an infinite space model;

[0015] The method for determining the total ionization dose and displacement damage dose caused by the reactor radiation environment is as follows:

[0016] The total ionizing dose caused by the reactor radiation environment is determined by the following formula:

[0017]

[0018] Among them, I γ is the total ionizing dose generated by the space reactor on the spacecraft platform; η γ is the conversion factor between gamma energy spectrum and total dose; is the gamma fluence during the mission;

[0019] The displacement damage dose caused by the reactor radiation environment is determined by the following formula:

[0020]

[0021] Among them, D 中子 is the displacement damage dose caused by the space reactor to the spacecraft platform; η 中子is the conversion coefficient between neutron energy spectrum and displacement damage dose; is the neutron fluence during the mission;

[0022] The reactor radiation environment needs to clearly define the reactor particle information, spacecraft spatial distribution information, and the total gamma ionization dose I suffered by the aircraft platform during the flight mission. γ , neutron displacement damage dose D 中子 ;

[0023] The reactor particle information includes the gamma energy spectrum and neutron energy spectrum generated by the space reactor after shadow shielding; the gamma radiation flux during the mission Neutron Fluence

[0024] The spacecraft spatial distribution information includes the space angle θ of the space reactor and the distance L between the space reactor and the spacecraft;

[0025] The steps of the method include:

[0026] The first step is to use the space radiation environment simulation software, input the spacecraft orbit parameters, and calculate the total ionizing dose I generated by the natural radiation environment to the spacecraft platform. 天然 ;

[0027] The second step is to calculate the total gamma dose I based on the reactor particle information and spacecraft spatial distribution information during the mission. γ ;

[0028] The third step is to use the space radiation environment simulation software to input the spacecraft orbit parameters and calculate the displacement damage dose D caused by the natural radiation environment to the spacecraft platform. 天然 ;

[0029] The fourth step is to calculate the neutron displacement damage dose D according to the reactor particle information and spacecraft spatial distribution information during the flight mission. 中子 ;

[0030] Step 5: The total ionization dose suffered by the aircraft platform during the mission is I = I 天然+ I γ ; The displacement damage dose suffered by the aircraft platform during the mission D = D 天然+ D 中子 .

[0031] Beneficial effects

[0032] Currently, the application of space reactors is in its infancy, and calculation methods for their comprehensive radiation environment are immature. Only methods exist for natural radiation conditions. This method is applicable to the comprehensive radiation environment of space reactor spacecraft. The total ionization dose to the spacecraft platform is the sum of the total ionization doses caused by the natural and artificial radiation environments; the displacement damage dose to the spacecraft platform is the sum of the displacement damage doses caused by the natural and artificial radiation environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the six numbers of satellite orbits;

[0034] Figure 2 Spacecraft layout for space reactors. DETAILED DESCRIPTION

[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0036] Example

[0037] A method for determining the radiation resistance index of a spacecraft in a comprehensive radiation environment includes the calculation of the total ionization dose and displacement damage dose caused by the natural radiation environment and the reactor radiation environment:

[0038] The natural radiation environment calculation requires clear orbit information of the space reactor and spacecraft; natural radiation environment simulation model; analysis structure model; space radiation environment simulation software;

[0039] The orbital information includes the orbital parameters, launch time, and mission period of the space reactor spacecraft. The orbital parameters include: semi-major axis a, eccentricity e, orbital inclination i, as well as the argument of periapsis ω, ascending node longitude Ω, and true anomaly at launch. The orbital information of the spacecraft can be determined by combining the six orbital numbers with the launch time and mission period, such as Figure 1 As shown;

[0040] The natural radiation environment simulation models include: AP8 / AE8, AP9 / AE9, IGE2006, MEOv2, FLUMIC, and NASA's worst energy spectrum. AP8 / AE8 or AP9 / AE9 is usually selected as the simulation model.

[0041] Table 1 Characteristics of commonly used models of Earth's radiation belts

[0042]

[0043] The analytical structural models mentioned above mainly include solid sphere, spherical shell, flat plate, infinite space, etc. Since the secondary effects of particles in different structural models are different, the calculation results of each model will vary. In conventional analysis, the solid sphere model is generally used for analysis.

[0044] The space radiation environment simulation software includes: Space radiation, FASTRAD, OMERE, Systema, SPENVIS, etc. The default aircraft shielding thickness is 3mm Al.

[0045] The reactor radiation environment needs to clarify the reactor particle information, space distribution information of the aircraft during the flight mission, and the total gamma ionization dose I suffered by the aircraft platform. γ , neutron displacement damage dose D 中子 ;

[0046] like Figure 2 As shown, the reactor particle information includes the gamma energy spectrum and neutron energy spectrum generated by the space reactor after shadow shielding; the gamma flux during the mission Neutron Fluence

[0047] The spacecraft spatial distribution information includes the space angle θ of the space reactor and the distance L between the space reactor and the spacecraft;

[0048] The total ionizing dose is determined by the following formula:

[0049]

[0050] Among them, I γ is the total ionizing dose generated by the space reactor to the spacecraft platform; η γ is the conversion factor between gamma energy spectrum and total dose; is the gamma fluence during the mission;

[0051] The displacement damage dose is determined by the following formula:

[0052]

[0053] Among them, D 中子 is the displacement damage dose caused by the space reactor to the spacecraft platform; η 中子 is the conversion coefficient between neutron energy spectrum and displacement damage dose; is the neutron fluence during the mission;

[0054] A method for determining a spacecraft radiation resistance index in a comprehensive radiation environment, the method comprising the following steps:

[0055] The first step is to use the space radiation environment simulation software, input the spacecraft orbit parameters, and calculate the total ionizing dose I generated by the natural radiation environment to the spacecraft platform. 天然 ;

[0056] The second step is to calculate the total gamma dose I based on the reactor particle information and spacecraft spatial distribution information during the mission. γ ;

[0057] The third step is to use the space radiation environment simulation software to input the spacecraft orbit parameters and calculate the displacement damage dose D caused by the natural radiation environment to the spacecraft platform. 天然 ;

[0058] The fourth step is to calculate the neutron displacement damage dose D according to the reactor particle information and spacecraft spatial distribution information during the flight mission. 中子 ;

[0059] Step 5: The total ionization dose suffered by the aircraft platform during the mission is I = I 天然+ I γ ; The displacement damage dose suffered by the aircraft platform during the mission D = D 天然+ D 中子 .

[0060] In this embodiment, the six orbital elements are selected as follows: semi-major axis a = 7200 km, eccentricity e = 0, orbit inclination i = 0, and the argument of pericenter ω = 0, the longitude of the ascending node Ω = 0, and the true anomaly angle The launch date is January 2025, with a mission life of 10 years. The natural radiation environment simulation model is AP8 / AE8. The analysis structure model is a solid sphere model. The space radiation environment simulation software is SPENVIS. The default spacecraft shielding thickness is 3mm Al. The gamma and neutron energy spectra are based on typical fast neutron reactor spectra. The gamma radiation dose is 6×10 10 / cm 2 , neutron injection 6×10 15 / cm 2 The spatial angle is 1.5π. The distance L between the space reactor and the spacecraft is 10m. Calculation result I 天然 =4.8krad(Si),I γ =20krad(Si),D 天然 =1.1×10 7 MeV / g,D 中子 =2×10 8 MeV / g. The total ionization dose I suffered by the spacecraft platform during the mission was 24.8krad(Si); the displacement damage dose D suffered by the spacecraft platform during the mission was 2.11×10 8 MeV / g.

Claims

1. A method for determining the radiation resistance index of a spacecraft in a comprehensive radiation environment, characterized by The steps of the method include: The first step is to use space radiation environment simulation software to calculate the total ionizing dose I generated by the natural radiation environment on the spacecraft platform. 天然 ; The second step is to calculate the total gamma dose I based on the reactor particle information and spacecraft spatial distribution information during the mission. γ ; The third step is to use space radiation environment simulation software to calculate the displacement damage dose D caused by the natural radiation environment to the spacecraft platform. 天然 ; The fourth step is to calculate the neutron displacement damage dose D according to the reactor particle information and spacecraft spatial distribution information during the flight mission. 中子 ; Step 5: The total ionization dose I = I suffered by the spacecraft platform during the mission 天然+ I γ ; The displacement damage dose suffered by the aircraft platform during the mission is D = D 天然+ D 中子 ; The reactor radiation environment needs to clearly define the reactor particle information, spacecraft spatial distribution information, and the total gamma ionization dose I suffered by the aircraft platform during the flight mission. γ , neutron displacement damage dose D 中子 ; The reactor particle information includes the gamma energy spectrum and neutron energy spectrum generated by the space reactor after shadow shielding; the gamma flux φ during the mission γ , neutron flux φ 中子 ; The spacecraft spatial distribution information includes the space angle θ of the space reactor and the distance L between the space reactor and the spacecraft; The total ionizing dose caused by the reactor radiation environment is determined by the following formula: I γ =h γ ×φ γ ×θ / 4π / L 2 Among them, I γ is the total ionizing dose generated by the space reactor on the spacecraft platform; η γ is the conversion coefficient between gamma energy spectrum and total dose; φ γ is the gamma fluence during the mission; The displacement damage dose caused by the reactor radiation environment is determined by the following formula: D 中子 =η 中子 ×φ 中子 ×θ / 4π / L 2 Among them, D 中子 is the displacement damage dose caused by the space reactor to the spacecraft platform; η 中子 is the conversion coefficient between neutron energy spectrum and displacement damage dose; φ 中子 is the neutron fluence during the mission.

2. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 1, characterized in that: The spacecraft radiation resistance index includes the total ionization dose and displacement damage dose caused by the natural radiation environment, and also includes the total ionization dose and displacement damage dose caused by the reactor radiation environment.

3. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 2, characterized in that: The method for determining the total ionization dose and displacement damage dose caused by the natural radiation environment is: The natural radiation environment is simulated using radiation environment simulation software to obtain the total ionization dose and displacement damage dose caused by the natural radiation environment.

4. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 3, characterized in that: The radiation environment simulation software is Space radiation, FASTRAD, OMERE, Systema or SPENVIS.

5. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 3, characterized in that: The input conditions for simulating the natural radiation environment include: the number of six orbits of the spacecraft, the launch time, the mission cycle, as well as the natural radiation environment simulation model and the analytical structure model.

6. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 5, characterized in that: The six orbital parameters of the spacecraft include the semi-major axis a, the eccentricity e, the orbital inclination i, as well as the argument of periapsis ω, the longitude of the ascending node Ω and the true anomaly φ at launch.

7. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 5, characterized in that: The natural radiation environment simulation model is AP8 / AE8, AP9 / AE9, IGE2006, MEOv2, FLUMIC or NASA's worst energy spectrum.

8. The method for determining a spacecraft radiation resistance index in a comprehensive radiation environment according to claim 5, characterized in that: The analytical structural model includes a solid sphere, a spherical shell model, a flat plate model or an infinite space model.

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