Method for calculating the internal depth-dose curve of a single machine

Abstract

The present invention provides a method for calculating the depth-dose curve inside a single machine, and belongs to the field of space environment analysis technology. The method includes: S1, calculating the input depth-dose curve, and selecting the hollow single machine shell to be analyzed; S2, performing ray tracing analysis to obtain the shielding depth value of each sector area; S3, adding the shielding depth value of each sector area with the shielding depth value of the input depth-dose curve, and then calculating the corresponding dose value according to the added shielding depth value, and constructing the output depth-dose curve with the shielding depth value of the input depth-dose curve and the dose value calculated according to the added shielding depth value; S4, accumulating the output depth-dose curve according to the weight of each sector area, and constructing the depth-dose curve inside the single machine. The present invention realizes the efficient and accurate conversion of the depth-dose curve of the external environment into the depth-dose curve of the single machine shell.

Description

Technical Field

[0001] The invention relates to the technical field of space environment analysis, and in particular to a method for calculating a single-machine internal depth-dose curve. Background Art

[0002] During the mission cycle of a spacecraft, the radiation sources that affect it are complex and changeable, but in the overall time period, they can be regarded as isotropic influences. In order to evaluate the radiation dose received by sensitive components and key units inside the spacecraft, engineering now often simulates the space environment to obtain the depth-dose curve of the external environment during the entire mission cycle, and then efficiently estimates the total radiation dose received by sensitive components and key units by looking up the depth-dose curve. The depth-dose curve represents the radiation dose corresponding to a certain shielding depth. The shielding depth distribution of the part to be evaluated is calculated. Through this equivalent method, an estimate of the total radiation dose can be obtained.

[0003] In the early stage of the design of a spacecraft, it is necessary to optimize the interior of the single machine according to the distribution of radiation effects inside the shell of the single machine to maximize the use of the existing design and improve the life and reliability of the single machine. However, for the interior of the single machine, it is usually necessary to participate in the estimation of radiation dose together with the three-dimensional structure of the entire spacecraft. In some cases, this calculation method will add unnecessary burden to the designers of the single machine. In the design layout stage of the interior of the single machine, for the hollow single machine shell where the equipment has not yet been arranged, if the depth-dose curve inside the single machine can be converted, it can provide great convenience for the optimization design of the interior of the single machine. However, the existing method of obtaining the depth-dose curve inside the single machine is generally by means of indirect conversion of the calculated energy spectrum, and such conversion is indirect and loses precision for the depth-dose curve. Therefore, it is urgent to provide a method for converting the depth-dose curve of the external environment into the depth-dose curve of the single machine shell in an efficient and precision-free manner. Summary of the invention

[0004] In view of the above problems in the prior art, the present invention provides a method for calculating the internal depth-dose curve of a single machine.

[0005] To achieve the above objectives, the present invention is specifically implemented through the following technologies:

[0006] The present invention provides a method for calculating a single-machine internal depth-dose curve, comprising the following steps:

[0007] S1. Obtain the energy spectrum data corresponding to the space environment during the spacecraft mission cycle, calculate the input depth-dose curve, and simultaneously construct a three-dimensional model of the spacecraft. Select the on-board equipment to be analyzed in the three-dimensional model of the spacecraft, remove the internal structure of the on-board equipment, and obtain a hollow on-board housing;

[0008] S2. Perform ray tracing analysis on the three-dimensional model of the spacecraft to obtain the shielding depth value of each sector region;

[0009] S3. Add the shielding depth value of each sector region to the shielding depth value of the input depth-dose curve to obtain the added shielding depth value, and then calculate the corresponding dose value based on the added shielding depth value. For each sector region, construct the output depth-dose curve with the shielding depth value of the input depth-dose curve and the dose value calculated based on the added shielding depth value;

[0010] S4. Accumulate the output depth-dose curve according to the weight of each sector region to construct the depth-dose curve inside the on-board equipment.

[0011] Further, in step S1, the thickness of the on-board housing is 10 mm, and the length, width, and height are 500 mm, 300 mm, and 300 mm respectively, and the material is aluminum.

[0012] Further, in step S1, the software for calculating the input depth-dose curve is shieldose software.

[0013] Further, in step S2, the specific operations of the ray tracing analysis include the following steps: Use a ray tracing program that meets the data requirements, set the detection point coordinates and the number of angle divisions, and perform the ray tracing analysis operation on the three-dimensional model of the spacecraft.

[0014] Furthermore, the detection point coordinates are the center point coordinates of the on-board housing, and the number of angle divisions is selected as 60×60.

[0015] Further, in step S3, the specific operations for calculating the corresponding dose value based on the added shielding depth value include the following steps: Sequentially search for the interval containing the added shielding depth value on the input depth-dose curve, perform linear interpolation, and calculate the dose value corresponding to the added shielding depth value.

[0016] Further, the calculation method of the linear interpolation includes: Given two end points (X0, Y0) and (X1, Y1), where X0 < X1, for the x for which interpolation is desired, calculate the interpolation result y according to the first formula, and the first formula includes:

[0017]

[0018] Among them, X0 is the abscissa value of the left - hand endpoint, X1 is the abscissa value of the right - hand endpoint, Y0 is the ordinate value of the left - hand endpoint, Y1 is the ordinate value of the right - hand endpoint, x is the abscissa value of the interpolation point to be performed, X0 < x < X1, and y is the ordinate value of the interpolation point to be performed.

[0019] Further, step S4 specifically includes the following steps: multiplying the weight of each of the fan - shaped regions by each of the dose values of the output depth - dose curve corresponding to the fan - shaped region, accumulating the obtained dose values, calculating the accumulated dose value, and constructing the depth - dose curve inside the single machine with the shielding depth value of the input depth - dose curve and the accumulated dose value.

[0020] Further, calculate the weight of each of the fan - shaped regions according to the second formula, and the second formula includes:

[0021]

[0022] Among them, W i is the weight, θ u is the upper limit of the polar angle of the fan - shaped region, θ L is the lower limit of the polar angle of the fan - shaped region, is the upper limit of the azimuth angle of the fan - shaped region, is the lower limit of the azimuth angle of the fan - shaped region.

[0023] Furthermore, the shielding depth value of the fan - shaped region is 1.05 g / cm 2 , and the weight of the fan - shaped region is 5.556e -4 .

[0024] The present invention provides a method for directly converting a depth - dose curve based on the shielding depth value obtained by ray - tracing analysis technology. On each spatial fan - shaped region divided by the ray - tracing analysis technology, first, simulate and analyze to obtain the shielding depth value of the fan - shaped region. Then, add the shielding depth value of each fan - shaped region to the shielding depth value of the original depth - dose curve to obtain the added shielding depth value. After conversion, the dose value is obtained, so as to obtain a converted depth - dose curve for each fan - shaped region. Weightedly accumulate the converted depth - dose curves obtained above according to the weight of the fan - shaped region, and the depth - dose curve inside the single machine can be directly obtained, making the most of the characteristics of the original depth - dose curve itself, avoiding indirect, time - consuming, and inaccurate conversion, and improving the conversion accuracy and conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 is a depth-dose curve corresponding to the spacecraft mission cycle in Example 1 of the present invention;

[0027] Figure 2 It is a schematic structural diagram of a three-dimensional model of a spacecraft and a single machine shell to be analyzed according to Embodiment 1 of the present invention;

[0028] Figure 3 Calculation result diagram of shielding depth value of the sector area of ​​embodiment 1 of the present invention;

[0029] Figure 4 This is a depth-dose curve diagram after conversion in Example 1 of the present invention;

[0030] Figure 5 It is a comparison diagram of the depth-dose curve inside the single machine and the input depth-dose curve in Example 1 of the present invention. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present invention can be combined with each other. In addition, the meanings of the terms "comprising", "containing", and "having" are non-restrictive, and other steps and other components that do not affect the results can be added. Unless otherwise specified, materials, equipment, and reagents are all commercially available.

[0032] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0033] An embodiment of the present invention provides a method for calculating a single-machine internal depth-dose curve, comprising the following steps:

[0034] S1. Obtain the energy spectrum data corresponding to the space environment where the spacecraft mission cycle is located, calculate the depth-dose curve corresponding to the spacecraft mission cycle (for ease of distinction, hereinafter referred to as the input depth-dose curve), and simultaneously build a three-dimensional model of the spacecraft, select the single-machine equipment to be analyzed in the three-dimensional model of the spacecraft, remove the internal structure of the single-machine equipment, and obtain a hollow single-machine shell.

[0035] Figure 1 The depth-dose curve of a spacecraft during its entire mission cycle is given as an example. Figure 2A simplified three-dimensional model of a spacecraft is shown in FIG. 1 , in which the inner shell is the single-unit shell to be analyzed, with a thickness of 10 mm, a length, width and height of 500 mm, 300 mm and 300 mm respectively, and is made of aluminum. The outer shell is a three-dimensional model of the spacecraft shell, and the arrows in the figure are coordinate axes. In the design and layout stage of the interior of the single-unit equipment, for the hollow single-unit shell where no equipment has been arranged, converting the depth-dose curve of the external environment into the depth-dose curve of the single-unit shell can greatly facilitate the optimization design of the internal structure of the single-unit shell.

[0036] The software program used for the above calculation of the depth-dose curve corresponding to the spacecraft mission cycle is shieldose software.

[0037] S2. Perform ray tracing analysis on the three-dimensional model of the spacecraft to obtain the shielding depth value of each sector area. The calculation results of the shielding depth value can be found in Figure 3 .

[0038] The specific operation of the ray tracing analysis described above includes the following steps: using a ray tracing program, setting the detection point coordinates and the number of angle divisions, and performing ray tracing analysis operations on the spacecraft three-dimensional model. Generally speaking, the ray tracing program is a certain program that meets the data requirements and conditions, the detection point coordinates are the center point coordinates of a single shell, and the number of angle divisions is 60×60.

[0039] S3. Add the shielding depth value of each sector area with the shielding depth value of the input depth-dose curve to obtain the added shielding depth value, and then calculate the corresponding dose value based on the added shielding depth value. For each sector area, construct the output depth-dose curve with the shielding depth value of the input depth-dose curve and the newly calculated dose value.

[0040] The specific operations of step S3 include the following steps: For each sector region, traverse each row of the depth-dose curve input in step S1, and add the shielding depth value of each sector region to the shielding depth value of each row of the input depth-dose curve. This is equivalent to translating the numerical values on the horizontal axis of the input depth-dose curve by the shielding depth value of the sector region, calculating the sum of the shielding depth values, and then sequentially searching for the interval containing the sum of the shielding depth values on the input depth-dose curve, performing linear interpolation, and calculating the dose value corresponding to the sum of the shielding depth values. For each sector region, construct the output depth-dose curve with the shielding depth value of the original input depth-dose curve and the newly calculated dose value. Thus, the number of output depth-dose curves formed is equal to the number of sector regions. The pseudo-code program description of the foregoing process is as follows. Here, Inputs DoseCurve is the depth-dose curve corresponding to the spacecraft mission cycle calculated in step S1, with two columns and seventy rows. X is the shielding depth value of the sector region calculated by ray tracing analysis. Outputs NewCurve is the converted depth-dose curve, and its format is the same as the Inputs DoseCurve array. Depth is the sum of the shielding depth values, and Dose is the dose value calculated by searching based on the sum of the shielding depth values.

[0041]

[0042] The calculation method of the above-mentioned linear interpolation includes: Given two endpoints: (X0, Y0) and (X1, Y1), where X0 < X1, for the x for which interpolation is desired, calculate the interpolation result y according to the first formula. The first formula includes:

[0043]

[0044] Among them, X0 is the abscissa value of the left endpoint, X1 is the abscissa value of the right endpoint, Y0 is the ordinate value of the left endpoint, Y1 is the ordinate value of the right endpoint, x is the abscissa value of the interpolation point for which interpolation is desired, X0 < x < X1, and y is the ordinate value of the interpolation point for which interpolation is desired.

[0045] Exemplarily, taking the shielding depth value X of one of the sector regions as 1.05 g / cm 2 as an example, the converted depth-dose curve (i.e., the output depth-dose curve) is shown in Figure 4 .

[0046] S4. Accumulate the output depth-dose curves according to the weight of each sector region to construct the depth-dose curve inside the single machine.

[0047] Specifically, the weight of each sector area is calculated according to a second formula, wherein the second formula includes:

[0048]

[0049] Among them, W i is the weight, θ u is the upper limit of the polar angle of the fan-shaped area, θ L is the lower limit of the polar angle of the fan-shaped area, is the upper limit of the azimuth angle of the fan-shaped area, It is the lower limit of the azimuth of the fan-shaped area. The units of the above parameters are all radians.

[0050] For example, Figure 3 The relevant parameters of the fan-shaped area in the calculation are calculated, and the weight result of the shielding depth value of each fan-shaped area is 5.556e -4 .

[0051] The specific operation of accumulating the output depth-dose curve according to the weight of each sector area to construct the depth-dose curve inside the single machine as described above includes: multiplying the weight of each sector area by each dose value of the output depth-dose curve of the corresponding sector area, accumulating the obtained dose values, calculating the accumulated dose value, and constructing the depth-dose curve inside the single machine with the shielding depth value of the original input depth-dose curve and the accumulated dose value.

[0052] With a weight of 5.556e -4 For example, the converted depth-dose curve inside a single machine is as follows Figure 5 As shown in the middle left figure, the original input depth-dose curve is as follows Figure 5 As shown in the middle right figure, after comparison, it can be seen that the maximum value of the depth-dose curve inside the single machine obtained by conversion is smaller and the rate of change is also smaller.

[0053] The present invention provides a method for directly converting a depth-dose curve based on a shielding depth value obtained by a ray tracing analysis technology. On each space sector area divided by the ray tracing analysis technology, a simulation analysis is first performed to obtain a shielding depth value of the sector area, and then the shielding depth value of each sector area is added to the shielding depth value of the original depth-dose curve to obtain the added shielding depth value, and then the dose value is obtained through conversion, so as to obtain a converted depth-dose curve for each sector area. The converted depth-dose curve obtained above is weightedly accumulated according to the weight of the sector area, and the depth-dose curve inside a single machine can be directly obtained, thereby making the most of the characteristics of the original depth-dose curve itself, avoiding indirect, time-consuming and inaccurate conversion, improving the conversion accuracy and conversion efficiency, and realizing efficient and accurate conversion of the depth-dose curve of the external environment into the depth-dose curve of the single machine shell.

[0054] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually based on the conditions recommended by the manufacturer.

[0055] Example 1

[0056] A method for calculating a single-machine internal depth-dose curve comprises the following steps:

[0057] S1. Obtain the energy spectrum data corresponding to the space environment of the spacecraft mission cycle, and use shield software to calculate the depth-dose curve corresponding to the spacecraft mission cycle as the input depth-dose curve. The format of the input depth-dose curve is usually referred to in Figure 1 At the same time, a three-dimensional model of the spacecraft is constructed, the single-machine equipment to be analyzed in the three-dimensional model of the spacecraft is selected, the internal structure of the single-machine equipment is removed, and a hollow single-machine shell is obtained. Figure 2 A simplified single-unit shell structure of a spacecraft three-dimensional model is shown in the figure, wherein the inner shell is the single-unit shell to be analyzed, with a thickness of 10 mm, a length, width and height of 500 mm, 300 mm and 300 mm respectively, and a material of aluminum; the outer shell is a three-dimensional model of the spacecraft shell, and the arrows in the figure are coordinate axes.

[0058] S2. Using a ray tracing program that meets the data requirements and conditions, set the detection point coordinates (in this embodiment, the center of the single-unit shell is used as the detection point) and the number of angle divisions (in this embodiment, the division score is 60×60), take the center of the single-unit shell as the detection point, perform ray tracing analysis on the three-dimensional model of the spacecraft, and obtain the shielding depth value of each sector area. The calculation result of the shielding depth value is shown in Figure 3 ;

[0059] S3. For each sector region, according to the following pseudocode program, take the input depth-dose curve obtained in step S1 as the Inputs DoseCurve array, take the shielding depth value of the sector region calculated by ray tracing analysis in step S2 as the input X value, traverse each row of the Inputs DoseCurve array, add the shielding depth value X of each sector region to the shielding depth value of each row of the input depth-dose curve Inputs DoseCurve array, which is equivalent to translating the horizontal axis value of the input depth-dose curve by the shielding depth value of the sector region, calculate the sum of the shielding depth values Depth, then sequentially search for the interval containing the sum of the shielding depth values Depth on the Inputs DoseCurve array, perform linear interpolation, calculate the dose value Dose corresponding to the sum of the shielding depth values Depth, and then construct the output depth-dose curve NewCurve with the shielding depth value of the original input depth-dose curve and the newly calculated dose value Dose. Taking X as 1.05 g / cm 2 as an example, the output depth-dose curve NewCurve is shown in Figure 4 ;

[0060]

[0061] The calculation method of linear interpolation includes: given two endpoints: (X0, Y0), (X1, Y1), where X0 < X1, for the x at which interpolation is desired, calculate the interpolation result y according to the first formula, and the first formula includes:

[0062]

[0063] where X0 is the abscissa value of the left endpoint, X1 is the abscissa value of the right endpoint, Y0 is the ordinate value of the left endpoint, Y1 is the ordinate value of the right endpoint, x is the abscissa value of the interpolation point at which interpolation is desired, X0 < x < X1, and y is the ordinate value of the interpolation point at which interpolation is desired.

[0064] S4. Calculate the weight of each sector region according to the second formula, multiply the weight of each sector region by each dose value of the output depth-dose curve of the corresponding sector region, and accumulate the obtained dose values onto the result depth-dose curve (i.e., the depth-dose curve inside the single machine), where the shielding depth value of the result depth-dose curve remains the shielding depth value of the input depth-dose curve, that is, construct the depth-dose curve inside the single machine with the shielding depth value of the original input depth-dose curve and the accumulated dose values. Calculate according to the second formula Figure 3The weight of the fan-shaped area represented by the shielding depth value is 5.556e -4 The shape comparison of the final depth-dose curve and the original depth-dose curve can be seen in Figure 5 The second formula includes:

[0065]

[0066] Among them, W i is the weight, θ u is the upper limit of the polar angle of the fan-shaped area, θ L is the lower limit of the polar angle of the fan-shaped area, is the upper limit of the azimuth angle of the fan-shaped area, is the lower limit of the azimuth angle of the fan-shaped area, W i ,θ u ,θ L , and The units are radians.

[0067] from Figure 5 It can be seen that the depth-dose curve inside the single machine obtained by conversion ( Figure 5 Compared with the original input depth-dose curve ( Figure 5 The maximum value (as shown in the middle right figure) is smaller and the rate of change is also smaller, which shows that the conversion efficiency and conversion accuracy of the method of the present invention are high.

Claims

1. A method for calculating a single-machine internal depth-dose curve, characterized in that: It includes the following steps: S1. Obtain the energy spectrum data corresponding to the space environment during the spacecraft mission cycle, calculate the input depth-dose curve, and simultaneously construct a three-dimensional model of the spacecraft. Select the on-board equipment to be analyzed in the three-dimensional model of the spacecraft, remove the internal structure of the on-board equipment, and obtain a hollow on-board housing. S2. Conduct ray tracing analysis on the three-dimensional model of the spacecraft to obtain the shielding depth value of each sector area. S3. Add the shielding depth value of each sector area to the shielding depth value of the input depth-dose curve to obtain the added shielding depth value. Then, calculate the corresponding dose value based on the added shielding depth value. For each sector area, construct the output depth-dose curve using the shielding depth value of the input depth-dose curve and the dose value calculated based on the added shielding depth value. Among them, in step S3, the specific operation of calculating the corresponding dose value based on the added shielding depth value includes the following steps: Sequentially search for the interval containing the added shielding depth value on the input depth-dose curve, perform linear interpolation, and calculate the dose value corresponding to the added shielding depth value. The calculation method of the linear interpolation includes: Given two end points (X0, Y0) and (X1, Y1), where X0 < X1, for the x for which interpolation is desired, calculate the interpolation result y according to the first formula, and the first formula includes: Where X0 is the abscissa value of the left end point, X1 is the abscissa value of the right end point, Y0 is the ordinate value of the left end point, Y1 is the ordinate value of the right end point, x is the abscissa value of the interpolation point, X0 < x < X1, and y is the ordinate value of the interpolation point. S4. Accumulate the output depth-dose curve according to the weight of each sector area to construct the depth-dose curve inside the on-board equipment.

2. The method according to claim 1, characterized in that In step S1, the thickness of the on-board housing is 10 mm, and the length, width, and height are 500 mm, 300 mm, and 300 mm respectively, and the material is aluminum.

3. The method according to claim 1, characterized in that: In step S1, the software for calculating the input depth-dose curve is shieldose software.

4. The method according to claim 1, characterized in that: In step S2, the specific operation of the ray tracing analysis includes the following steps: Use a ray tracing program that meets the data requirements, set the detection point coordinates and the number of angle divisions, and perform the ray tracing analysis operation on the three-dimensional model of the spacecraft.

5. The method according to claim 4, characterized in that The detection point coordinates are the center point coordinates of the on-board housing, and the number of angle divisions is selected as 60×60.

6. The method according to claim 1, characterized in that Step S4 specifically includes the following steps: Multiply the weight of each sector area by each dose value of the output depth-dose curve corresponding to the sector area, accumulate the obtained dose values, calculate the accumulated dose value, and construct the depth-dose curve inside the on-board equipment using the shielding depth value of the input depth-dose curve and the accumulated dose value.

7. The method according to claim 1, characterized in that Calculate the weight of each sector area according to the second formula, and the second formula includes: Among them, W i is the weight, θ u is the upper limit of the polar angle of the fan-shaped area, θ L is the lower limit of the polar angle of the fan-shaped area, is the upper limit of the azimuth angle of the fan-shaped area, is the lower limit of the azimuth of the fan-shaped area.

8. The method according to any one of claims 1 to 7, characterized in that: The shielding depth value of the sector area is 1.05 g / cm 2 , the weight of the sector area is 5.556e -4 .

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