Electromagnetic sensitive solid propellant burning rate active regulation method and device

Abstract

The present invention discloses a method and device for actively controlling the burning rate of electromagnetically sensitive solid propellants. The method arranges a plurality of electromagnetic coils in parallel around the electromagnetically sensitive solid propellant, combines a step-by-step scanning control strategy, and utilizes the current feedback loaded by the electromagnetic coils to accurately identify the position of the burning surface. The program control system then turns on the power supply of a certain unit electromagnetic coil to control the burning rate of the electromagnetically sensitive solid propellant, thereby achieving the purpose of actively controlling the burning rate of the solid propellant. The device includes a parameter determination unit, an installation unit, a wiring unit, a calculation unit, a judgment unit, and an active control unit. The present invention solves the technical problems that the combustion process of the grain in a solid rocket engine cannot be controlled in real time and the engine energy management level is poor.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solid rocket engines, and particularly relates to a method and device for actively regulating the burning rate of electromagnetically sensitive solid propellant. BACKGROUND

[0002] In order to obtain better trajectory performance and use performance, the missile weapon or rocket overall often hopes that the size of the thrust of the engine can be real-time adjustable and controllable to realize efficient energy management. However, the solid propellant grain of the traditional solid rocket engine is ignited in the combustion chamber, and the combustion process cannot be real-time regulated, so that the engine thrust output is difficult to be real-time adjusted, and the energy management level is poor. In the existing technical solutions, the solid rocket engine capable of real-time changing the thrust is typically represented by the plug-type variable-thrust solid rocket engine, and the principle is to change the throat passage cross-sectional area of the nozzle by controlling the movement of the plug, so as to change the size of the engine thrust. However, due to the fact that the plug is directly exposed to the harsh environment of high pressure, high temperature, high speed and multi-phase scouring of the nozzle, the plug has a very serious ablation problem, the profile is difficult to maintain, the thrust is difficult to accurately regulate, and the engine size and working time are strictly required. In addition, the variable-thrust solid rocket engine scheme based on electrically controlled propellant is still in the exploratory stage, and has the disadvantages of low energy level of the propellant, difficulty in electrode arrangement and the need for additional energy supply. Therefore, the existing technical solutions all have certain problems and application limitations. SUMMARY

[0003] In order to overcome the defects of the above-mentioned prior art, the purpose of the present application is to provide a method and device for actively regulating the burning rate of electromagnetically sensitive solid propellant, so as to solve the technical problem that the combustion process of the propellant grain in the solid rocket engine cannot be real-time regulated, and the engine energy management level is poor.

[0004] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0005] A method for actively regulating the burning rate of electromagnetically sensitive solid propellant, comprising the following steps:

[0006] 1) Determine the size of the electromagnetically sensitive solid propellant, the size of the electromagnetic coil unit, the frequency and voltage parameters of the electromagnetic generator, and determine the number of electromagnetic coil units through the ratio of the height of the propellant to the height of the electromagnetic coil unit;

[0007] 2) Place the electromagnetically sensitive solid propellant on the object table, and place the electromagnetic coil around the propellant to ensure that the electromagnetic coil is coaxial and equal in height with the propellant;

[0008] 3) Connect each electromagnetic coil unit with the current sensor, the electromagnetic generator and the power supply of the electromagnetic generator by using wires to form a loop, and the electromagnetic coil units are connected in parallel in the circuit;

[0009] 4) Turn off the power supply of the electromagnetic generator, ignite the electromagnetically sensitive propellant by the laser igniter, open the high-speed camera to record the regression of the propellant combustion surface, calculate the propellant burning rate by the Matlab program, and obtain the propellant burning rate r0 without electromagnetic field excitation;

[0010] 5) Turn on the power supply of the electromagnetic generator, set the voltage as U1, and record the current I change in the regression process of the electromagnetically sensitive propellant in each electromagnetic coil unit. When the combustion surface passes through the electromagnetically sensitive material, the material melts due to high temperature, and the current in the electromagnetic coil unit is greatly reduced. Record the current value I min as the current threshold value. When the current I i <I min of the i-th electromagnetic coil unit is less than the current threshold value, it is considered that the electromagnetically sensitive material melts at this position, that is, the combustion surface passes through this position.

[0011] 6) Design the upper computer control program according to the current threshold value in step 5), control the on-off state of the electromagnetic coil unit according to the burning rate requirement, and thus realize the active control of the burning rate of the electromagnetically sensitive propellant.

[0012] Further improvement of the present application is that the size of the electromagnetically sensitive solid propellant is determined, including: the shape, height, length, width or diameter of the electromagnetically sensitive propellant; and the size of the electromagnetic coil unit is determined, including: the wire diameter, circumferential diameter and coil spacing of the electromagnetic coil.

[0013] Further improvement of the present application is that the shape of the electromagnetically sensitive propellant is a cuboid or a cylinder.

[0014] Further improvement of the present application is that the voltage determination method of the electromagnetic generator is: energizing a certain electromagnetic coil unit, gradually increasing the voltage value from 0 V, recording the minimum voltage U0 that can cause the electromagnetically sensitive propellant to self-ignite, and ensuring that the subsequent applied voltage value is not greater than 0.7 U0.

[0015] Further improvement of the present application is that the method for calculating the propellant burning rate by the Matlab program is: converting the color image obtained by the high-speed camera into a black and white image, i.e. a gray scale image, by using the rgb2gray function in the Matlab software; determining the gray scale threshold value H for finding the position of the propellant combustion surface, calculating the actual length corresponding to a single pixel, determining the height of the combustion surface in each image, calculating the height L and the time t of the regression of the combustion surface from the beginning to the end of the combustion, and obtaining the burning rate of the propellant by the formula r=L / t.

[0016] Further improvement of the present application is that the electromagnetically sensitive material includes copper, iron and silver, and wires or rods of iron-nickel alloy.

[0017] Further improvement of the present application is that the upper computer control program includes: determining the current threshold value Imin , judge the current I of the i unit i and I min , if the current I i is greater than I min , it indicates that the electromagnetic sensitive material is not fused, and the combustion surface does not pass through the electromagnetic coil unit, at this time, the power supply is not opened for combustion rate adjustment; if the current I i is less than I min , it indicates that the electromagnetic sensitive material is fused, and the combustion surface passes through the electromagnetic coil unit, the electromagnetic generator power supply is opened, the electromagnetic coil unit parameters are adjusted, and the combustion rate is adjusted.

[0018] An electromagnetic sensitive solid propellant combustion rate active regulation device, comprising:

[0019] A parameter determination unit for determining the size of the electromagnetic sensitive solid propellant, the size of the electromagnetic coil unit, the frequency and voltage parameters of the electromagnetic generator; the number of electromagnetic coil units is determined by the ratio of the height of the propellant to the height of the electromagnetic coil unit;

[0020] A mounting unit for placing the electromagnetic sensitive solid propellant on the object table, and placing the electromagnetic coil around the propellant to ensure that the electromagnetic coil and the propellant are coaxial and isometric;

[0021] A wiring unit for connecting each electromagnetic coil unit with the current sensor, the electromagnetic generator and the electromagnetic generator power supply by using wires to form a loop, and the electromagnetic coil units are connected in parallel in the circuit;

[0022] A calculation unit for closing the electromagnetic generator power supply, igniting the electromagnetic sensitive propellant by using a laser igniter, opening a high-speed camera to record the propellant combustion surface recession, calculating the propellant combustion rate by using a Matlab program, and obtaining the propellant combustion rate r0 without electromagnetic field excitation;

[0023] A judgment unit for opening the electromagnetic generator power supply, setting the voltage to U1, recording the current I change of the electromagnetic sensitive propellant in the recession process of each electromagnetic coil unit, when the combustion surface passes through the electromagnetic sensitive material, the material is fused due to high temperature, the current in the electromagnetic coil unit is greatly reduced, and the current value I min after fusion is recorded as the current threshold, when the current I i of the i electromagnetic coil unit is less than I min , it is considered that the electromagnetic sensitive material is fused at this position, that is, the combustion surface passes through this position;

[0024] An active regulation unit for designing a host computer control program according to the current threshold in the judgment unit, regulating the on-off state of the electromagnetic coil unit according to the combustion rate demand, and then realizing the active regulation of the electromagnetic sensitive propellant combustion rate.

[0025] The further improvement of the application is that the electromagnetic sensitive solid propellant size determination in the parameter determination unit comprises: electromagnetic sensitive propellant shape, height, length, width or diameter; and the electromagnetic coil unit size determination comprises: electromagnetic coil wire diameter, circumference diameter and coil spacing.

[0026] The further improvement of the application is that the electromagnetic generator voltage determination method in the parameter determination unit is: gradually increasing the voltage value from 0 V for a certain electromagnetic coil unit, recording the minimum voltage U0 that can cause the self-ignition of the electromagnetic sensitive propellant, and ensuring that the subsequent applied voltage value is not greater than 0.7 U0.

[0027] Compared with the prior art, the application has at least the following beneficial technical effects:

[0028] The application provides a technical method and device for active regulation of the burning rate of a solid propellant grain, wherein multiple-stage electromagnetic heating coils are arranged in parallel around the solid propellant grain, when the burning rate of the solid propellant grain needs to be regulated, electromagnetic heating is performed by gradually opening the high-frequency power supply cabinets under the control of a program control system, and according to the working current fed back by the high-frequency power supply cabinets in real time, if the working current fed back by a certain unit high-frequency power supply is large, it means that the solid propellant in the electromagnetic heating coil has not been burned out, so the burning surface position is determined, and the electromagnetic heating coil power supply near the burning surface is opened to regulate the burning rate, and the subsequent unit coil regulation is completed in the same way, so that the electromagnetic heating effect is dynamically loaded with the change of the solid propellant burning surface. This scheme changes the shortcoming that the traditional solid propellant can only release energy according to the preset rule after being ignited, and the parallel arrangement and sequential control of multiple unit electromagnetic coils ensure safety and realize precise and controlled loading of electromagnetic excitation. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the application or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0030] Figure 1 It is a schematic diagram of the host computer program.

[0031] Figure 2 It is a schematic diagram of the experimental device of the application.

[0032] Figure 3 It is a schematic diagram of the experimental results of typical burning rate processed by Matlab in the embodiment.

[0033] Figure 4This is a structural block diagram of an electromagnetically sensitive solid propellant burning rate active control device of the present invention. DETAILED DESCRIPTION

[0034] Hereinafter, only certain exemplary embodiments are briefly described. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are to be considered as illustrative in nature and not restrictive.

[0035] It will be understood that when used in this specification and the appended claims, the terms “comprises” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0036] It should also be understood that the terms used in the present specification are only for the purpose of describing particular embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0037] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0038] The accompanying drawings illustrate various schematic diagrams of structures according to embodiments disclosed herein. These figures are not drawn to scale; for clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0039] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0040] Example 1

[0041] like Figure 2 As shown, the present invention provides a method for actively controlling the burning rate of electromagnetically sensitive solid propellants, comprising the following steps:

[0042] 1) Determine the size of the electromagnetic sensitive solid propellant, the size of the electromagnetic coil unit, and the frequency and voltage parameters of the electromagnetic generator; determine the number of electromagnetic coil units by the ratio of the propellant height to the electromagnetic coil unit height;

[0043] 2) Place the electromagnetic sensitive solid propellant on the stage, and place the electromagnetic coil around the propellant to ensure that the electromagnetic coil is coaxial with the propellant and has the same height;

[0044] 3) Connect each electromagnetic coil unit with the current sensor, the electromagnetic generator, and the electromagnetic generator power supply by wires to form a loop, and the electromagnetic coil unit is connected in parallel in the circuit;

[0045] 4) Turn off the electromagnetic generator power supply, ignite the electromagnetic sensitive propellant with a laser igniter, open the high-speed camera to record the propellant combustion surface recession, calculate the propellant burning rate using the Matlab program, and obtain the propellant burning rate r0 without electromagnetic field excitation;

[0046] 5) Turn on the electromagnetic generator power supply, set the voltage to U1, and record the current I change of the electromagnetic sensitive propellant during the recession process. When the combustion surface passes through the electromagnetic sensitive material, the material melts due to high temperature, and the current in the electromagnetic coil unit decreases significantly. Record the current value I min as the current threshold. When the current I i <I min of the i-th electromagnetic coil unit is less than I

[0047] 6) Design the upper computer control program according to the current threshold in step 5), adjust the on-off state of the electromagnetic coil unit according to the burning rate requirement, and realize the active regulation of the electromagnetic sensitive propellant burning rate.

[0048] In this embodiment, the size of the electromagnetic sensitive solid propellant is determined, including: the shape, height, length, width or diameter of the electromagnetic sensitive propellant; the size of the electromagnetic coil unit is determined, including: the wire diameter, circumference diameter and coil spacing of the electromagnetic coil.

[0049] In this embodiment, the electromagnetic sensitive propellant is in the shape of a cuboid or a cylinder.

[0050] In this embodiment, the voltage determination method of the electromagnetic generator is: energize a certain electromagnetic coil unit, gradually increase the voltage value from 0 V, record the minimum voltage U0 that can cause the electromagnetic sensitive propellant to self-ignite, and ensure that the subsequent applied voltage value is not greater than 0.7 U0.

[0051] In the embodiment, the method for calculating the propellant burning rate by using the Matlab program is as follows: the color image obtained by the high-speed camera is converted into a black-and-white image, i.e., a gray-scale image, by using the rgb2gray function in the Matlab software; the gray value threshold H is determined for finding the propellant burning surface position; the actual length corresponding to a single pixel is calculated; the height of the burning surface in each image is determined; the height L and the time t of the burning surface retreat from the beginning to the end of the burning are calculated; and the propellant burning rate is obtained by the formula r=L / t.

[0052] In the embodiment, the electromagnetic sensitive material includes a wire or rod of copper, iron, silver, and iron-nickel alloy.

[0053] In the embodiment, the host computer control program, as shown in Figure 1 includes: determining the electromagnetic coil unit current threshold I min , judging the size relationship between the current I i of the i unit and I min , if the current I i is greater than I min , it indicates that the electromagnetic sensitive material is not fused, and the burning surface does not pass through the electromagnetic coil unit, at this time, the power supply is not needed to be turned on for the burning rate adjustment; if the current I i is less than I min , it indicates that the electromagnetic sensitive material is fused, and the burning surface passes through the electromagnetic coil unit, the electromagnetic generator power supply is turned on, the electromagnetic coil unit parameters are adjusted, and the burning rate adjustment is performed.

[0054] Embodiment 2

[0055] 1) The size of the electromagnetic sensitive solid propellant is determined to be 5 mm×5 mm×50 mm, the electromagnetic sensitive material is a 0.4 mm iron wire located in the center of the propellant, the electromagnetic coil unit size includes a wire diameter of 2.5 mm, a circumferential diameter of 50 mm, a coil spacing of 5 mm, an electromagnetic coil unit height of 10 mm, an electromagnetic generator frequency of 77 kHz, and a voltage of 0-55 V adjustable; the number of electromagnetic coil units is determined to be 5 through the ratio of the propellant height 50 mm to the electromagnetic coil unit height 10 mm;

[0056] 2) The 50 mm electromagnetic sensitive solid propellant is placed on the object table, and the five 10 mm electromagnetic coil units are placed on the periphery of the propellant to ensure that the electromagnetic coils are coaxial and equal in height with the propellant;

[0057] 3) The wires are used to connect each electromagnetic coil unit with the current sensor, the electromagnetic generator, and the electromagnetic generator power supply to form a loop, and the electromagnetic coil units are connected in parallel in the circuit;

[0058] 4) Turn off the power supply of the electromagnetic generator, ignite the electromagnetically sensitive propellant with a laser igniter, open the high-speed camera (resolution 500x800, frame rate 2000 fps) to record the regression of the propellant combustion surface, and calculate the propellant burning rate using a Matlab program, as shown in the first electromagnetic coil unit, the propellant burning rate r0=1.16 mm / s without electromagnetic field excitation is obtained; Figure 3

[0059] 5) Turn on the power supply of the electromagnetic generator, set the voltage to U1=60 V, and record the current I change of the electromagnetically sensitive propellant during the regression of the first and second electromagnetic coil units. When the combustion surface passes through the electromagnetically sensitive material, the material melts due to high temperature, the current in the first electromagnetic coil unit decreases significantly, and the current value I min =0.01 A is recorded as the current threshold. When the current I2 of the second electromagnetic coil unit is less than I min , it is considered that the electromagnetically sensitive material is melted, that is, the combustion surface passes through this place;

[0060] 6) Design the upper computer control program according to the current threshold in step 5), control the voltage and evaluation rate of the second electromagnetic coil unit, and realize the control effect of increasing the burning rate of the electromagnetically sensitive propellant by 2 times.

[0061] Example 3

[0062] As shown in the Figure 4 , the application provides an electromagnetic sensitive solid propellant burning rate active control device, which comprises:

[0063] A parameter determination unit is used to determine the size of the electromagnetically sensitive solid propellant, the size of the electromagnetic coil unit, the frequency and voltage parameters of the electromagnetic generator, and the number of electromagnetic coil units through the ratio of the height of the propellant to the height of the electromagnetic coil unit;

[0064] A mounting unit is used to place the electromagnetically sensitive solid propellant on the object table, and the electromagnetic coil is placed around the propellant to ensure that the electromagnetic coil and the propellant are coaxial and isometric;

[0065] A wiring unit is used to connect each electromagnetic coil unit with the current sensor, the electromagnetic generator and the power supply of the electromagnetic generator by wires to form a loop, and the electromagnetic coil units are connected in parallel in the circuit;

[0066] A calculation unit is used to turn off the power supply of the electromagnetic generator, ignite the electromagnetically sensitive propellant with a laser igniter, open the high-speed camera to record the regression of the propellant combustion surface, and calculate the propellant burning rate using a Matlab program, and obtain the propellant burning rate r0 without electromagnetic field excitation;

[0067] ​A judging unit is configured to open the power supply of the electromagnetic generator, set the voltage to U1, and record the current I change of the electromagnetic sensitive propellant during the retreat of each electromagnetic coil unit, when the combustion surface passes through the electromagnetic sensitive material, the material is fused due to high temperature, and the current in the electromagnetic coil unit is greatly reduced, and the current value I in the loop after the fusion is recorded min is the current threshold value, when the current I of the i-th electromagnetic coil unit i <I min , it is considered that the electromagnetic sensitive material is fused at this position, i.e., the combustion surface passes through this position.

[0068] An active regulation unit is configured to design a host computer control program according to the current threshold value in the judging unit, regulate the on-off state of the electromagnetic coil unit according to the burning rate requirement, and thus realize the active regulation of the burning rate of the electromagnetic sensitive propellant.

[0069] In the embodiment, the size of the electromagnetic sensitive solid propellant in the parameter determining unit includes: the shape, height, length, width or diameter of the electromagnetic sensitive propellant; and the size of the electromagnetic coil unit includes: the wire diameter, circumferential diameter and coil spacing of the electromagnetic coil.

[0070] In the embodiment, the voltage determination method of the electromagnetic generator in the parameter determining unit is: energizing a certain electromagnetic coil unit, gradually increasing the voltage value from 0 V, recording the minimum voltage U0 that can cause the electromagnetic sensitive propellant to self-ignite, and ensuring that the subsequent applied voltage value is not greater than 0.7 U0.

[0071] In summary, the present application controls the burning rate by arranging multiple-stage electromagnetic heating coils in parallel around the solid propellant grain and using electromagnetic heating to control the burning rate. When it is necessary to control the burning rate of the solid propellant grain, the program control system is used to sequentially open the high-frequency power supply cabinet for electromagnetic heating. According to the real-time feedback of the working current of the high-frequency power supply cabinet, if the working current of a certain unit high-frequency power supply is relatively large, it means that the solid propellant in the electromagnetic heating coil has not been burned out, so the position of the combustion surface is determined, and the electromagnetic heating coil power near the combustion surface is turned on for burning rate control. In this way, the subsequent unit coil control is completed, and the electromagnetic heating effect is dynamically loaded with the change of the solid propellant combustion surface. This scheme changes the shortcoming that the traditional solid propellant can only release energy according to the preset rule after ignition, and at the same time, the parallel arrangement and sequential control of multiple unit electromagnetic coils ensure safety and realize precise and controlled loading of electromagnetic excitation.

[0072] The foregoing merely illustrates the principles of the application and application of its leading features. This application is not limited to the exact details shown above and described herein, and obvious modifications will occur to those skilled in the art upon reading the foregoing description. Therefore, the scope of the application is not to be determined by the specific examples shown above, but only by the claims below. Any reference signs in the claims should not be construed as limiting the scope of the claims.

[0073] Furthermore, it should be appreciated that although the present specification describes particular embodiments, these are merely examples of the same, and that the specification is not limited to only the particular embodiments described. The scope of the present specification extends to all alternatives, modifications, additions and / or deletions, which take into account the technical ideas of the present specification, and which are obvious to those skilled in the art.

Claims

1. A method for actively controlling the burning rate of electromagnetically sensitive solid propellants, characterized in that: The following steps are involved: 1) Determine the size of the electromagnetic sensitive solid propellant, the size of the electromagnetic coil unit, and the frequency and voltage parameters of the electromagnetic generator; determine the number of electromagnetic coil units by the ratio of the propellant height to the electromagnetic coil unit height; 2) Place the electromagnetically sensitive solid propellant on the stage and the electromagnetic coil around the propellant, ensuring that the electromagnetic coil and the propellant are coaxial and at the same height. 3) Using wires to connect each electromagnetic coil unit to the current sensor, the electromagnetic generator, and the electromagnetic generator power supply to form a loop, with the electromagnetic coil units connected in parallel in the circuit; 4) Turn off the power supply of the electromagnetic generator, use the laser igniter to ignite the electromagnetically sensitive propellant, turn on the high-speed camera to record the propellant burning surface retreat, use the Matlab program to calculate the propellant burning rate, and obtain the propellant burning rate r0 without electromagnetic field excitation; 5) Turn on the power supply of the electromagnetic generator, set the voltage to U1, and record the change of the current I of the electromagnetic sensitive propellant during the retreat process of each electromagnetic coil unit. When the burning surface passes through the electromagnetic sensitive material, the material melts due to the high temperature, and the current in the electromagnetic coil unit drops significantly. Record the current value I in the circuit after the melting. min is the current threshold, when the current I i <I min When the electromagnetic sensitive material is melted, the burning surface passes through this place; 6) Design a host computer control program based on the current threshold in step 5) to regulate the on / off status of the electromagnetic coil unit according to the burning rate requirement, thereby achieving active regulation of the burning rate of the electromagnetic sensitive propellant.

2. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 1, characterized in that: The size of the electromagnetic sensitive solid propellant is determined, including: the shape, height, length, width or diameter of the electromagnetic sensitive propellant; the size of the electromagnetic coil unit is determined, including: the electromagnetic coil wire diameter, circumferential diameter and coil spacing.

3. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 2, characterized in that: The electromagnetically sensitive propellant is in the shape of a cuboid or a cylinder.

4. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 1, characterized in that: The method for determining the voltage of the electromagnetic generator is as follows: energize a certain electromagnetic coil unit, gradually increase the voltage value from 0 V, record the minimum voltage U0 that can cause the electromagnetic sensitive propellant to spontaneously ignite, and ensure that the subsequently applied voltage value is no more than 0.7 U0.

5. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 1, characterized in that: The method for calculating the propellant burning rate using the Matlab program is as follows: the color image obtained by the high-speed camera is converted into a black and white image, that is, a grayscale image, using the rgb2gray function in the Matlab software; the grayscale value threshold H is determined to find the position of the propellant burning surface, the actual length corresponding to a single pixel is calculated, the height of the burning surface in each image is determined, and the height L and time t of the burning surface retreat from the start to the end of combustion are calculated. The burning rate of the propellant is obtained using the formula r=L / t.

6. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 1, characterized in that: Electromagnetically sensitive materials include copper, iron, and silver, as well as wires or rods of iron-nickel alloys.

7. The method for actively controlling the burning rate of electromagnetically sensitive solid propellant according to claim 1, characterized in that: The host computer control program includes: determining the electromagnetic coil unit current threshold I min , determine the current I of unit i i with I min If the current I i Greater than I min , indicating that the electromagnetic sensitive material has not been melted and the burning surface has not passed through the electromagnetic coil unit. At this time, there is no need to turn on the power supply to adjust the burning rate; if the current I i Less than I min , indicating that the electromagnetic sensitive material has melted and the burning surface has passed through the electromagnetic coil unit. Turn on the power supply of the electromagnetic generator, adjust the parameters of the electromagnetic coil unit, and adjust the burning rate.

8. An electromagnetically sensitive solid propellant burning rate active control device, characterized in that: include: A parameter determination unit is used to determine the size of the electromagnetic sensitive solid propellant, the size of the electromagnetic coil unit, the frequency and voltage parameters of the electromagnetic generator; and the number of electromagnetic coil units is determined by the ratio of the propellant height to the electromagnetic coil unit height; The mounting unit is used to place the electromagnetic sensitive solid propellant on the stage, and the electromagnetic coil is placed outside the propellant to ensure that the electromagnetic coil and the propellant are coaxial and at the same height; A wiring unit, used to connect each electromagnetic coil unit with the current sensor, the electromagnetic generator and the electromagnetic generator power supply using a wire to form a loop, wherein the electromagnetic coil units are connected in parallel in the circuit; The calculation unit is used to turn off the power supply of the electromagnetic generator, ignite the electromagnetic sensitive propellant using a laser igniter, turn on a high-speed camera to record the retreat of the propellant burning surface, calculate the propellant burning rate using a Matlab program, and obtain the propellant burning rate r0 without electromagnetic field excitation; The judgment unit is used to turn on the power supply of the electromagnetic generator, set the voltage to U1, and record the change of the current I of the electromagnetic sensitive propellant during the retreat process of each electromagnetic coil unit. When the burning surface passes through the electromagnetic sensitive material, the material melts due to the high temperature, and the current in the electromagnetic coil unit drops significantly. The current value I in the circuit after the melting is recorded. min is the current threshold, when the current I i <I min When the electromagnetic sensitive material is melted, the burning surface passes through this place; The active control unit is used to design the host computer control program based on the current threshold in the judgment unit, and to control the on-off status of the electromagnetic coil unit according to the burning rate requirements, thereby realizing active control of the burning rate of the electromagnetic sensitive propellant.

9. The electromagnetically sensitive solid propellant burning rate active control device according to claim 8, characterized in that: In the parameter determination unit, the size of the electromagnetic sensitive solid propellant is determined, including: the shape, height, length, width or diameter of the electromagnetic sensitive propellant; the size of the electromagnetic coil unit is determined, including: the electromagnetic coil wire diameter, circumferential diameter and coil spacing.

10. The electromagnetically sensitive solid propellant burning rate active control device according to claim 8, characterized in that: In the parameter determination unit, the method for determining the electromagnetic generator voltage is as follows: energize a certain electromagnetic coil unit, gradually increase the voltage value from 0 V, record the minimum voltage U0 that can cause the electromagnetic sensitive propellant to spontaneously ignite, and ensure that the subsequently applied voltage value is no more than 0.7 U0.

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