Engineering and numerical value combined light environment design method

Abstract

The invention discloses a light environment design method combining engineering and numerical values. The light environment design method comprises the following steps: carrying out numerical calculation of a three-dimensional thermochemical unbalanced flow field; selecting a typical observation window, and generating observation rays penetrating through the flow field area; interpolating the numerical calculation result of the three-dimensional thermochemical unbalanced flow field to the observation rays to obtain density and temperature data on different observation rays; calculating a high-temperature gas emission coefficient at each point on the observation ray based on a high-temperature gas visible light wave band radiation engineering calculation formula; integrating along an observation ray path to obtain a background flow field light radiation intensity value Isim of each point on the light path reaching the optical window; light environment measurement data of a previous flight test are used, a background flow field light radiation intensity simulation value Isim0 of each point on a light path reaching the optical window is obtained through the method, the simulation value Isim0 is compared with a measured value Iexp, and a light environment simulation correction factor f = Iexp / Isim0 is obtained; and multiplying the light environment simulation correction factor by a background flow field light radiation intensity value Isim of the optical window to obtain a light environment design result.

Description

Technical Field

[0001] The invention relates to a light environment design method combining engineering and numerical value, which can be used for the simulation and design of the light environment of the complex flow field at the tail of a high-speed aircraft, and belongs to the field of overall design of high-speed aircraft. Background Art

[0002] As the range of inertial navigation increases, its navigation and positioning error accumulates and increases over time. The combined navigation method based on star sensors and inertial systems can significantly improve the accuracy of strikes. However, for near-space high-speed aircraft, the gas around the aircraft is severely compressed and the temperature rises sharply, forming a complex multi-state particle component state. Under high temperature conditions, a large number of high-energy states of multi-state particles are successively excited, causing the surrounding flow field gas to emit self-luminous radiation, forming background interference for starlight detection. In engineering, many factors are taken into account. Generally, star sensors are installed at the bottom of the aircraft. The strong expansion non-equilibrium complex flow field at the bottom is very complex. Numerical simulation requires the use of a three-dimensional high-temperature non-equilibrium / radiation coupling model, which has a large amount of calculations and a long cycle, and is extremely difficult to accurately predict. Summary of the invention

[0003] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a light environment design method that combines engineering with numerical values, to improve computational efficiency, and to integrate flight test light environment data for rapid correction.

[0004] The technical solution of the present invention is: in the first aspect, a light environment design method combining engineering and numerical methods is provided, wherein:

[0005] S1. For typical flight conditions in the optical detection section of the flight orbit, numerical calculation of three-dimensional thermochemical non-equilibrium flow field is carried out according to the typical flight condition altitude, speed and angle of attack;

[0006] S2. According to the optical detection field of view, a typical observation window within the detection field of view is selected, and observation rays are generated in all directions with the center of the observation window as the origin, so that the observation rays pass through the flow field area in S1;

[0007] S3, interpolating the numerical calculation results of the three-dimensional thermochemical non-equilibrium flow field obtained in S1 to the observation rays in S2 to obtain density and temperature data on different observation rays;

[0008] S4. According to the density and temperature data of each point on the observation ray, based on the radiation engineering calculation formula of high-temperature gas in the visible light band, calculate the high-temperature gas emission coefficient J at each point on the observation ray. ω ;

[0009] S5. Based on the high-temperature gas emission coefficient at each point on the optical path obtained in S4, the background flow field light radiation intensity value I of each point on the optical path reaching the optical window is obtained by integrating along the observation ray path. sim ;

[0010] S6. Using the light environment measurement data of previous flight tests, the simulation value of the background flow field light radiation intensity I reaching the optical window at each point on the light path is obtained by calculation through the methods of S1 to S5. sim0 , compared with the measured value of the background flow field light radiation intensity I obtained during the flight test exp By comparison, we can obtain the light environment simulation correction factor f=I exp / I sim0 ;

[0011] S7, multiply the light environment simulation correction factor obtained in S6 by the background flow field light radiation intensity value I of the optical window obtained in S5 sim , and applied as a result of light environment design.

[0012] Preferably, when selecting a typical observation window within the detection field of view, the central optical axis direction and different pitch angles and circular angles should be included.

[0013] Preferably, the high temperature gas emission coefficient J at each point on the observation ray is calculated ω , specifically:

[0014] J ω =k p B ω

[0015] in,

[0016]

[0017] k p represents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature;

[0018] B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

[0019] Preferably, the background flow field light radiation intensity value I reaching the optical window at each point on the light path is sim for:

[0020] I sim =∫0 l J ω dl

[0021] Where l is the distance from the point on the observation ray to the observation origin.

[0022] In the second aspect, a light environment design system combining engineering and numerical methods is provided, including: a three-dimensional thermochemical non-equilibrium flow field numerical calculation module, an observation ray generation module, an interpolation solution module, a high-temperature gas emission coefficient calculation module, a background flow field light radiation intensity value calculation module, a light environment simulation correction factor calculation module, and a light environment design result generation module; wherein:

[0023] The three-dimensional thermochemical non-equilibrium flow field numerical calculation module performs three-dimensional thermochemical non-equilibrium flow field numerical calculation for typical flight conditions in the optical detection section of the flight track according to the typical flight condition altitude, speed and angle of attack, and sends the results to the interpolation solution module;

[0024] The observation ray generation module selects a typical observation window within the detection field of view according to the optical detection field of view, takes the center of the observation window as the origin, generates observation rays in all directions, and makes the observation rays pass through the flow field area set in the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, and sends the observation ray information in all directions to the interpolation solution module;

[0025] The interpolation solution module interpolates the three-dimensional thermochemical non-equilibrium flow field numerical calculation results obtained by the three-dimensional thermochemical non-equilibrium flow field numerical calculation module to the observation ray obtained by the observation ray generation module to obtain density and temperature data on different observation rays;

[0026] The high-temperature gas emission coefficient calculation module calculates the high-temperature gas emission coefficient J at each point on the observation ray based on the obtained density and temperature data of each point on the observation ray and the high-temperature gas visible light band radiation engineering calculation formula. ω , and send it to the background flow field light radiation intensity value calculation module;

[0027] The background flow field light radiation intensity value calculation module obtains the background flow field light radiation intensity value I at each point on the light path according to the high temperature gas emission coefficient calculation module, and integrates along the observation ray path. sim , and send it to the light environment design result generation module;

[0028] The light environment simulation correction factor calculation module uses the light environment measurement data of previous flight tests, calls the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, the observation ray generation module, the interpolation solution module, the high-temperature gas emission coefficient calculation module and the background flow field light radiation intensity value calculation module to calculate and obtain the background flow field light radiation intensity simulation value I of each point on the light path reaching the optical window. sim0 , compared with the measured value of the background flow field light radiation intensity I obtained during the flight test exp By comparison, we can obtain the light environment simulation correction factor f=Iexp / I sim0 , and send it to the light environment design result generation module;

[0029] The light environment design result generation module multiplies the light environment simulation correction factor obtained by the light environment simulation correction factor calculation module by the background flow field light radiation intensity value I of the optical window obtained by the background flow field light radiation intensity value calculation module. sim , and output as the light environment design result.

[0030] Preferably, when the observation ray generation module selects a typical observation window within the detection field of view, it should include the direction of the central optical axis and directions of different pitch angles and circular angles.

[0031] Preferably, the high temperature gas emission coefficient calculation module calculates the high temperature gas emission coefficient J at each point on the observation ray. ω , specifically:

[0032] J ω =k p B ω

[0033] in,

[0034]

[0035] k p represents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature;

[0036] B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

[0037] Preferably, the background flow field light radiation intensity value calculation module calculates the background flow field light radiation intensity value I of each point on the light path reaching the optical window. sim hour:

[0038] I sim =∫0 l J ω dl

[0039] Where l is the distance from the point on the observation ray to the observation origin.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] (1) The present invention adopts a light environment design method that combines engineering and numerical methods, which has high calculation efficiency;

[0042] (2) The present invention can integrate flight test light environment data to carry out rapid correction. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the aircraft optical detection device and light path of the present invention. DETAILED DESCRIPTION

[0044] Aiming at the problem of designing the light environment of the complex flow field at the tail of a high-speed aircraft, the present invention provides a light environment design method combining engineering and numerical methods. The technical characteristics of this method are: combining engineering and numerical methods, high calculation efficiency, and the ability to integrate flight test light environment data for rapid correction.

[0045] 1. For typical flight conditions in the optical detection section of the flight orbit, the typical flight conditions should cover the characteristics of altitude and angle of attack changes. Based on the altitude, speed and angle of attack of the typical flight conditions, numerical calculation of three-dimensional thermochemical non-equilibrium flow field should be carried out.

[0046] 2. According to the optical detection field of view, such as Figure 1 As shown, a typical observation window within the detection field of view is selected, which should include the central optical axis direction and different pitch angles and circular angle directions. With the center of the observation window as the origin, observation rays are generated in all directions so that the observation rays pass through the flow field area in step 1.

[0047] 3. According to the flow field simulation results obtained in step 1, the three-dimensional thermochemical non-equilibrium flow field numerical simulation results are interpolated to the observation rays in step 2 to obtain density and temperature data on different observation rays.

[0048] 4. According to the density and temperature data of each point along the observation ray obtained in step 3, the high-temperature gas emission coefficient J at each point on the observation ray is calculated based on the following high-temperature gas visible light band radiation engineering calculation formula: ω .

[0049] J ω =k p B ω

[0050] in,

[0051]

[0052] k p represents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature;

[0053] B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

[0054] 5. Based on the high-temperature gas emission coefficient at each point on the optical path obtained in step 4, the background flow field light radiation intensity reaching the optical window at each point on the optical path can be obtained by integrating along the observation ray path.

[0055]

[0056] Where l is the distance from the point on the observation ray to the observation origin, J ω is the emission coefficient at this point.

[0057] 6. Based on the previous flight test light environment measurement data, perform steps 1 to 5 according to the flight state corresponding to the test to obtain the light environment background flow field light radiation intensity simulation value I under the flight test state. sim0 and compared with the measured value of the background flow field light radiation intensity I obtained from the flight test exp By comparison, we can obtain the light environment simulation correction factor f=I exp / I sim0 7. According to the light environment simulation correction factor obtained in step 6, multiply the background flow field light radiation intensity value I of the optical window obtained in step 5 sim , and applied as a result of light environment design.

[0058] In a second aspect, the present invention provides a light environment design system combining engineering and numerical methods, including: a three-dimensional thermochemical non-equilibrium flow field numerical calculation module, an observation ray generation module, an interpolation solution module, a high-temperature gas emission coefficient calculation module, a background flow field light radiation intensity value calculation module, a light environment simulation correction factor calculation module, and a light environment design result generation module; wherein:

[0059] The three-dimensional thermochemical non-equilibrium flow field numerical calculation module performs three-dimensional thermochemical non-equilibrium flow field numerical calculation for typical flight conditions in the optical detection section of the flight track according to the typical flight condition altitude, speed and angle of attack, and sends the results to the interpolation solution module;

[0060] The observation ray generation module selects a typical observation window within the detection field of view according to the optical detection field of view, takes the center of the observation window as the origin, generates observation rays in all directions, and makes the observation rays pass through the flow field area set in the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, and sends the observation ray information in all directions to the interpolation solution module;

[0061] The interpolation solution module interpolates the three-dimensional thermochemical non-equilibrium flow field numerical calculation results obtained by the three-dimensional thermochemical non-equilibrium flow field numerical calculation module to the observation ray obtained by the observation ray generation module to obtain density and temperature data on different observation rays;

[0062] The high-temperature gas emission coefficient calculation module calculates the high-temperature gas emission coefficient J at each point on the observation ray based on the obtained density and temperature data of each point on the observation ray and the high-temperature gas visible light band radiation engineering calculation formula. ω , and send it to the background flow field light radiation intensity value calculation module;

[0063] The background flow field light radiation intensity value calculation module obtains the background flow field light radiation intensity value I at each point on the light path according to the high temperature gas emission coefficient calculation module, and integrates along the observation ray path. sim , and send it to the light environment design result generation module;

[0064] The light environment simulation correction factor calculation module uses the light environment measurement data of previous flight tests, calls the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, the observation ray generation module, the interpolation solution module, the high-temperature gas emission coefficient calculation module and the background flow field light radiation intensity value calculation module to calculate and obtain the background flow field light radiation intensity simulation value I of each point on the light path reaching the optical window. sim0 , compared with the measured value of the background flow field light radiation intensity I obtained during the flight test exp By comparison, we can obtain the light environment simulation correction factor f=I exp / I sim0 , and send it to the light environment design result generation module;

[0065] The light environment design result generation module multiplies the light environment simulation correction factor obtained by the light environment simulation correction factor calculation module by the background flow field light radiation intensity value I of the optical window obtained by the background flow field light radiation intensity value calculation module. sim , and output as the light environment design result.

[0066] When the observation ray generation module selects a typical observation window within the detection field of view, it should include the direction of the central optical axis and the directions of different pitch angles and circular angles.

[0067] The high temperature gas emission coefficient calculation module calculates the high temperature gas emission coefficient J at each point on the observation ray. ω , specifically:

[0068] J ω =k p B ω

[0069] in,

[0070]

[0071] k prepresents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature;

[0072] B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

[0073] The background flow field light radiation intensity value calculation module calculates the background flow field light radiation intensity value I of each point on the optical path reaching the optical window. sim hour:

[0074] I sim =∫0 l J ω dl

[0075] Where l is the distance from the point on the observation ray to the observation origin.

[0076] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in this field.

Claims

1. A light environment design method combining engineering and numerical methods, characterized in that include: S1. For typical flight conditions in the optical detection section of the flight orbit, numerical calculation of three-dimensional thermochemical non-equilibrium flow field is carried out according to the typical flight condition altitude, speed and angle of attack; S2. According to the optical detection field of view, a typical observation window within the detection field of view is selected, and observation rays are generated in all directions with the center of the observation window as the origin, so that the observation rays pass through the flow field area in S1; S3, interpolating the numerical calculation results of the three-dimensional thermochemical non-equilibrium flow field obtained in S1 to the observation rays in S2 to obtain density and temperature data on different observation rays; S4. According to the density and temperature data of each point on the observation ray, based on the radiation engineering calculation formula of high-temperature gas in the visible light band, calculate the high-temperature gas emission coefficient J at each point on the observation ray. ω ; S5. Based on the high-temperature gas emission coefficient at each point on the optical path obtained in S4, the background flow field light radiation intensity value I of each point on the optical path reaching the optical window is obtained by integrating along the observation ray path. sim ; S6. Using the light environment measurement data of previous flight tests, the simulation value I of the background flow field light radiation intensity reaching the optical window at each point on the light path is obtained by calculation through the methods of S1 to S5. sim0 , compared with the measured value of the background flow field light radiation intensity I obtained during the flight test exp By comparison, we can obtain the light environment simulation correction factor f=I exp / I sim0 ; S7, multiply the light environment simulation correction factor obtained in S6 by the background flow field light radiation intensity value I of the optical window obtained in S5 sim , and applied as a result of light environment design.

2. The method for designing a light environment combining engineering and numerical methods according to claim 1, characterized in that: When selecting a typical observation window within the detection field of view, the direction of the central optical axis as well as the directions of different pitch angles and circular angles should be included.

3. The method for designing a light environment combining engineering and numerical methods according to claim 1, characterized in that: Calculate the high temperature gas emission coefficient J at each point on the observation ray ω , specifically: J ω =k p B ω in, k p represents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature; B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

4. The method for designing a light environment combining engineering and numerical methods according to claim 1, characterized in that: The background flow field light radiation intensity value I reaching the optical window at each point on the optical path sim for: I sim =∫0 l J ω dl Where l is the distance from the point on the observation ray to the observation origin.

5. A light environment design system combining engineering and numerical methods, characterized in that include: Three-dimensional thermochemical non-equilibrium flow field numerical calculation module, observation ray generation module, interpolation solution module, high-temperature gas emission coefficient calculation module, background flow field light radiation intensity value calculation module, light environment simulation correction factor calculation module and light environment design result generation module; Among them: The three-dimensional thermochemical non-equilibrium flow field numerical calculation module performs three-dimensional thermochemical non-equilibrium flow field numerical calculation for typical flight conditions in the optical detection section of the flight track according to the typical flight condition altitude, speed and angle of attack, and sends the results to the interpolation solution module; The observation ray generation module selects a typical observation window within the detection field of view according to the optical detection field of view, takes the center of the observation window as the origin, generates observation rays in all directions, and makes the observation rays pass through the flow field area set in the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, and sends the observation ray information in all directions to the interpolation solution module; The interpolation solution module interpolates the three-dimensional thermochemical non-equilibrium flow field numerical calculation results obtained by the three-dimensional thermochemical non-equilibrium flow field numerical calculation module to the observation ray obtained by the observation ray generation module to obtain density and temperature data on different observation rays; The high-temperature gas emission coefficient calculation module calculates the high-temperature gas emission coefficient J at each point on the observation ray based on the obtained density and temperature data of each point on the observation ray and the high-temperature gas visible light band radiation engineering calculation formula. ω , and send it to the background flow field light radiation intensity value calculation module; The background flow field light radiation intensity value calculation module obtains the background flow field light radiation intensity value I at each point on the light path according to the high temperature gas emission coefficient calculation module, and integrates along the observation ray path. sim , and send it to the light environment design result generation module; The light environment simulation correction factor calculation module uses the light environment measurement data of previous flight tests, calls the three-dimensional thermochemical non-equilibrium flow field numerical calculation module, the observation ray generation module, the interpolation solution module, the high-temperature gas emission coefficient calculation module and the background flow field light radiation intensity value calculation module to calculate and obtain the background flow field light radiation intensity simulation value I of each point on the light path reaching the optical window. sim0 , compared with the measured value of the background flow field light radiation intensity I obtained during the flight test exp By comparison, we can obtain the light environment simulation correction factor f=I exp / I sim0 , and send it to the light environment design result generation module; The light environment design result generation module multiplies the light environment simulation correction factor obtained by the light environment simulation correction factor calculation module by the background flow field light radiation intensity value I of the optical window obtained by the background flow field light radiation intensity value calculation module. sim , and output as the light environment design result.

6. The light environment design system combining engineering and numerical values ​​according to claim 5, characterized in that: When the observation ray generation module selects a typical observation window within the detection field of view, it should include the direction of the central optical axis and the directions of different pitch angles and circular angles.

7. The light environment design system combining engineering and numerical values ​​according to claim 5, characterized in that: The high temperature gas emission coefficient calculation module calculates the high temperature gas emission coefficient J at each point on the observation ray. ω , specifically: J ω =k p B ω in, k p represents the emission coefficient proportional factor, ρ represents the flow field temperature, ρ0 represents the sea level atmospheric density, and T represents the flow field temperature; B ω represents the blackbody radiation coefficient, ω represents the wave number, h represents the Planck constant, c represents the speed of light, λ represents the wavelength, and k represents the Boltzmann constant.

8. The light environment design system combining engineering and numerical values ​​according to claim 1, characterized in that: The background flow field light radiation intensity value calculation module calculates the background flow field light radiation intensity value I of each point on the optical path reaching the optical window. sim hour: I sim =∫0 l J ω dl Where l is the distance from the point on the observation ray to the observation origin.

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