A device for regulating solid propellant combustion by coupling electric and magnetic fields

Abstract

This invention relates to the field of solid fuel engine technology, specifically to a device for controlling solid propellant combustion through electric and magnetic field coupling. The device includes a base plate with a left and right base fixedly mounted on it. A combustion chamber is fixed on each base, with a top cover at the right end and a Laval nozzle fixedly connected to the left end. The combustion chamber is filled with solid propellant and a combustion surface monitoring device for tracking the combustion surface. A displaceable physical field application device is located outside the combustion chamber to apply various physical fields to the combustion surface. A drive assembly is mounted on the base plate. The device also includes a monitoring and control unit for collecting data, calculating the position and velocity of the combustion surface within the combustion chamber, and controlling the drive assembly to displace the physical field application device. This allows for the application of electric and magnetic field coupling excitation to the solid propellant, enabling the study of the influence of electric and magnetic field coupling on solid propellant combustion.

Description

Technical Field

[0001] This invention relates to the field of solid fuel engine technology, specifically to a device for regulating solid propellant combustion by coupling electric and magnetic fields. Background Technology

[0002] Solid propellant is an energetic material containing both oxidizer and fuel, processed in a special way. It can burn in the absence of oxygen, producing a large amount of incandescent gas, and its combustion is often difficult to control. Solid propellants are generally used in aerospace or rocket engines. Due to this characteristic, once the engine is ignited, the solid propellant will continue to burn, making it extremely difficult to extinguish, and the engine thrust is difficult to adjust, which limits its development.

[0003] Existing control methods typically involve altering the throat area of ​​the Laval nozzle, but these methods are often structurally complex and prone to severe ablation. Therefore, in recent years, the use of external electric, acoustic, and magnetic fields to adjust the burning rate and efficiency of solid propellants in real time has been explored, enabling online dynamic control of solid propellant combustion. However, existing control methods often rely on a single energy field, and experimental equipment that uses coupled electric and magnetic fields to excite combustion is still scarce. Research on applying energy fields to the two-stage combustion region of solid-fuel engines remains incomplete. Furthermore, existing control devices often provide a single energy field direction, limiting their ability to study the intrinsic mechanisms of multi-physics-enhanced solid rocket engine combustion.

[0004] Therefore, it is necessary to invent a device for regulating solid propellant combustion by coupling electric and magnetic fields to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a device for regulating solid propellant combustion by coupling electric and magnetic fields, in order to overcome the problem that existing regulating devices have a single given energy field direction, which limits the study of the intrinsic mechanism of multi-physics field enhanced solid rocket engine combustion. This invention further studies the mechanism of solid propellant combustion in solid fuel engines by coupling electric and magnetic fields. This invention can simultaneously establish electric and magnetic fields in the combustion surface region of solid propellant, and establish magnetic fields in the throat and expansion section of the Laval nozzle to regulate thrust.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] An electric field and magnetic field coupled control device for solid propellant combustion includes a base plate, on which a left base and a right base are fixedly mounted. A combustion chamber is fixedly mounted on both the left and right bases. A top cover is provided at the right end of the combustion chamber. A Laval nozzle is fixedly connected to the left end of the combustion chamber and is coaxially arranged with the combustion chamber. The interior of the combustion chamber is filled with solid propellant and a combustion surface monitoring device for tracking the combustion surface of the solid propellant. A displaceable physical field application device is provided on the outside of the combustion chamber for applying various physical fields to the combustion surface. A drive component for displacing the physical field application device is installed on the base plate.

[0008] It also includes a monitoring and control device for collecting data and calculating the position and speed of the combustion surface in the combustion chamber, and controlling the drive assembly to pull the physical field application device to a certain displacement.

[0009] Furthermore, the physical field application device includes a mounting frame fitted onto the combustion chamber, with a sleeve fitted onto the combustion chamber hanging inside the mounting frame. A coil is wound around the sleeve, with the two ends of the coil connected to the positive and negative poles of a power supply. Applying direct current to the coil establishes a magnetic field, which can apply a stable magnetic field to the combustion chamber. A first set of electrode plates is provided at the upper and lower ends of the mounting frame, with the positive and negative poles of a DC high-voltage power supply connected to the first set of electrode plates. Applying voltage establishes an electric field, which can apply an electric field in the vertical direction to the combustion chamber. A second set of electrode plates is provided at the front and rear ends of the mounting frame, with the positive and negative poles of a DC high-voltage power supply connected to the second set of electrode plates. Applying voltage establishes an electric field, which can apply an electric field in the front and rear direction to the combustion chamber.

[0010] Furthermore, the drive assembly includes inverted U-shaped sliders fixed to the four corners of the lower end of the placement frame. Two slide rails arranged in the same direction as the combustion chamber are fixed on the base plate, and the sliders are slidably engaged with the slide rails located directly below. A force transmission shaft is fixedly installed at the lower corner of the placement frame. A motor is installed on the base plate on the same side as the force transmission shaft. A drum is fixedly mounted on the output shaft of the motor, and a force transmission rope is wound on the drum. The free end of the force transmission rope is fixedly connected to the force transmission shaft.

[0011] Furthermore, a magnetic field application device is provided on the outer side of the Laval nozzle. The magnetic field application device includes a support frame that is fitted on the outer side of the Laval nozzle and fixed to the base plate. A cylindrical tube fitted on the Laval nozzle is hung inside the support frame. A second coil is wound on the cylindrical tube. The two ends of the second coil are respectively connected to the positive and negative poles of the second power supply. Direct current is passed through the second coil to establish a magnetic field, which can apply a stable magnetic field to the Laval nozzle.

[0012] Furthermore, the sleeve and cylindrical tube are both coaxial with the combustion chamber; when direct current is applied to coil one and coil two, the magnetic field strength and direction can be changed by changing the magnitude and direction of the current; and there are multiple sets of coil one and coil two, with each set of coil one being supplied with a current of different intensities to achieve a gradual magnetic field; and each set of coil two being supplied with a current of different intensities to achieve a gradual magnetic field.

[0013] The first group of electrode plates and the second group of electrode plates each include a positive electrode plate and a negative electrode plate. The positive electrode plate and the negative electrode plate are fixed to the placement frame by a connecting rod. The positive electrode plate and the negative electrode plate can be interchanged to change the direction of the electric field, and the electric field strength can be changed by changing the magnitude of the applied current and voltage.

[0014] Furthermore, the combustion surface monitoring device includes several resistors connected in parallel via wires. These resistors are connected in series as a whole with a protective resistor, a power supply, and an ammeter, and the distance between the nodes connecting each resistor to the wires is equal. The several resistors, the protective resistor, the power supply, and the ammeter are all installed in the integrated device, except for the wires.

[0015] The wire is placed into the combustion chamber along with the solid propellant, and the axis of the wire is parallel to the axis of the combustion chamber. After the solid propellant is ignited, the wire located on the combustion surface is burned off, and the node connected to the resistor is also burned off. The current cannot flow through the resistor, causing the ammeter current to change. Since the distance between each node is equal, the combustion speed of the combustion surface can be obtained from the change of the ammeter and the time interval between two changes. Then, the position of the combustion surface can be calculated from the magnitude of the current change.

[0016] Furthermore, the monitoring and control device includes a computer, and the integrated device is electrically connected to the input terminal of the computer. The integrated device transmits the current change signal to the computer for calculating and analyzing the combustion speed and position of the combustion surface.

[0017] The monitoring and control device also includes a pressure tapping tube, a pressure transmitter, a thrust sensor, and a temperature sensor; a connecting hole is provided on the expansion wall at the left end of the Laval nozzle, and a pressure tapping tube is connected inside the connecting hole. The output end of the pressure tapping tube is connected to the input end of the pressure transmitter, and the output end of the pressure transmitter is electrically connected to the input end of the computer. A thrust sensor and a temperature sensor are installed on the side of the connecting hole, and the output ends of the thrust sensor and the temperature sensor are both electrically connected to the input end of the computer.

[0018] The monitoring and control device also includes a high-speed camera, which is installed on the side of the Laval nozzle exit, at the same height as the horizontal axis of the combustion chamber, and is used to capture the shape of the flame at the Laval nozzle exit; the output of the high-speed camera is electrically connected to the input of the computer.

[0019] The computer's output terminal is electrically connected to the motor's input terminal. The computer can control the motor's rotation speed by measuring the combustion speed and position of the combustion surface, thereby controlling the speed and position of the placement rack, so that the electric and magnetic fields on the placement rack can always act on the combustion surface of the solid propellant.

[0020] Furthermore, the computer calculation and analysis of the combustion rate and location of the combustion surface includes the following steps:

[0021] Step S1: Let the length of the solid propellant be L, the number of parallel resistors be n, and the distance between the nodes of the parallel resistors be equal, each being X.

[0022] ;

[0023] In the formula, L represents the length of the solid propellant, in meters; n represents the number of parallel resistors; and X represents the distance between two adjacent parallel resistor nodes, in meters.

[0024] Step S2: The time interval between changes in the ammeter reading as combustion progresses is recorded as t. j (j=1,2,3,…n-1), then the velocity V of the burning surface at different nodes i (i=2,3,4…n) can be estimated as:

[0025] ;

[0026] In the formula, t j The time interval for the change in the ammeter reading, expressed in seconds; V i The velocity of the combustion surface at different nodes, in meters per second;

[0027] Step S3: All parallel resistors are equal, let's call them R, and the protective resistor is R0. Then, the magnitude of the current I0 before combustion begins is:

[0028] ;

[0029] In the formula, R represents the resistance value of the parallel resistor, in ohms; R0 represents the resistance value of the protective resistor, in ohms; and U represents the total voltage value of the circuit, in volts. This represents the electric current before combustion begins, measured in amperes.

[0030] The magnitude of the current when combustion reaches the a-th (a=1,2,3…n) node. for:

[0031] ;

[0032] The position S of the combustion surface can then be calculated as:

[0033] S = (a-1) * X.

[0034] Furthermore, the lower right end face of the Laval nozzle is fixedly connected to the left base, and a flange is fixedly connected to the right end of the combustion chamber. The flange is fixedly connected to the top cover by bolts, and the lower end face of the flange is fixedly connected to the right base.

[0035] Furthermore, the longitudinal section of the top cover is convex, which can push solid propellant into the combustion chamber. The combustion chamber is horizontally placed and made of a non-magnetic and high-temperature resistant material that can be penetrated by electric and magnetic fields.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. A device for regulating solid propellant combustion by coupling electric and magnetic fields, which can apply electric and magnetic field coupled excitation to solid propellant to study the effect of electric and magnetic field coupling on solid propellant combustion.

[0038] 2. A device for regulating solid propellant combustion by coupling electric and magnetic fields, wherein the applied electric field is perpendicular to the axis of the combustion chamber and consists of two sets of orthogonally placed positive and negative electrode plates, which can simultaneously adjust the electric field excitation in two directions.

[0039] 3. An electric field and magnetic field coupled control device for solid propellant combustion, which can follow and control the combustion surface of solid propellant during combustion through a physical field application device and a drive component, so that the electric field and magnetic field excitation can always act on the combustion surface of solid propellant.

[0040] 4. An electric field and magnetic field coupled control device for solid propellant combustion, which regulates the secondary combustion process of a solid fuel engine by applying a magnetic field and regulates the engine thrust by establishing magnetic field excitation at the throat and expansion section of a Laval nozzle. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 .

[0042] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 .

[0043] Figure 3 This is a schematic diagram of the monitoring and control device in this invention.

[0044] Figure 4 This is a schematic cross-sectional view of the combustion chamber in this invention.

[0045] Figure 5 This is a schematic diagram of the combustion surface monitoring device in this invention.

[0046] Figure 6 This is a schematic diagram of the physical field application device in this invention.

[0047] In the diagram: 1-base plate, 2-left base, 3-right base, 4-combustion chamber, 5-top cover, 6-Laval nozzle, 7-solid propellant;

[0048] 8-Placement rack, 9-Sleeve, 10-Coil 1, 11-First group of electrode plates, 12-Second group of electrode plates, 13-Slider, 14-Slide rail frame, 15-Force transmission shaft, 16-Motor, 17-Shelf, 18-Cylindrical cylinder, 19-Coil 2, 20-Connecting rod;

[0049] 21-Wire, 22-Resistor, 23-Protective resistor, 24-Power supply, 25-Ammeter;

[0050] 26-Computer, 27-Pressure tap, 28-Pressure transmitter, 29-Thrust sensor, 30-Temperature sensor, 31-Connecting hole, 32-High-speed camera, 33-Flange, 34-Integrated device. Detailed Implementation

[0051] The present invention will now be described in further detail with reference to the accompanying drawings and specific preferred embodiments.

[0052] In the description of this invention, it should be understood that the terms "left side," "right side," "inner side," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. The specific dimensions used in this embodiment are only for illustrating the technical solution and do not limit the scope of protection of this invention.

[0053] An electric field and magnetic field coupled control device for solid propellant combustion includes a base plate 1, a left base 2 and a right base 3 fixedly mounted on the base plate 1, a combustion chamber 4 fixedly mounted on the left base 2 and the right base 3, a top cover 5 provided at the right end of the combustion chamber 4, a Laval nozzle 6 fixedly connected to the left end of the combustion chamber 4 and coaxially arranged with the combustion chamber 4, a solid propellant 7 and a combustion surface monitoring device for tracking the combustion surface of the solid propellant 7 are filled inside the combustion chamber 4, a displaceable physical field application device is provided outside the combustion chamber 4 for applying various physical fields to the combustion surface, and a drive component for displacing the physical field application device is installed on the base plate 1;

[0054] It also includes a monitoring and control device for collecting data and calculating the position and speed of the combustion surface in the combustion chamber 4, and controlling the drive assembly to pull the physical field application device to a certain displacement.

[0055] In this invention, the base plate 1 is fixed and serves as the experimental platform for combustion of the combustion chamber 4. The left base 2 and right base 3 are used to fix the combustion chamber 4. The top cover 5 is used to open and close the combustion chamber 4 and serves as the inlet for the solid propellant 7 and the outlet for the combustion residue. The physical field application device can apply two energy fields (electric field and magnetic field) to the primary combustion zone. The primary combustion zone refers to the area where the combustion surface of the solid propellant 7 is located. The drive component can pull the physical field application device to move with the movement of the combustion surface. The combustion surface monitoring device is used to track the combustion surface of the solid propellant 7. The calculation and control processes are controlled by the monitoring and control device.

[0056] The following details the physical field application device, driving component, combustion surface monitoring device, and monitoring and control device of this invention.

[0057] The physical field application device includes a mounting frame 8 fitted onto the combustion chamber 4, with a sleeve 9 fitted onto the combustion chamber 4 hanging inside the mounting frame 8. A coil 10 is wound around the sleeve 9, with the two ends of the coil 10 connected to the positive and negative poles of a power supply. Applying direct current to the coil 10 establishes a magnetic field, which can apply a stable magnetic field to the combustion chamber 4. A first set of electrode plates 11 is provided at the upper and lower ends of the mounting frame 8, with the positive and negative poles of a DC high-voltage power supply connected to the first set of electrode plates 11. Applying voltage establishes an electric field, which can apply an electric field in the vertical direction to the combustion chamber 4. A second set of electrode plates 12 is provided at the front and rear ends of the mounting frame 8, with the positive and negative poles of a DC high-voltage power supply connected to the second set of electrode plates 12. Applying voltage establishes an electric field, which can apply an electric field in the front and rear direction to the combustion chamber 4.

[0058] The sleeve 9, coil 10, and power supply form a magnetic field application assembly. The sleeve 9 is coaxially sleeved on the combustion chamber 4, and the coil 10 is wound around the sleeve 9. When DC current is applied to the coil 10, the magnetic field strength and direction can be changed by changing the magnitude and direction of the current. There are multiple sets of coil 10, and each set of coil 10 is supplied with a current of different intensities to achieve a gradual magnetic field (gradually increasing electric field and decreasing magnetic field).

[0059] The first group of electrode plates 11 and the second group of electrode plates 12 each include a positive electrode plate and a negative electrode plate. The positive electrode plate and the negative electrode plate are fixed to the placement frame 8 by a connecting rod 20. The positive electrode plate and the negative electrode plate can be interchanged to change the direction of the electric field, and the electric field strength can be changed by changing the magnitude of the current and voltage applied.

[0060] The drive assembly includes inverted U-shaped sliders 13 fixed to the four corners of the lower end of the placement frame 8. Two slide rails 14 arranged in the same direction as the combustion chamber 4 are fixed on the base plate 1, and the sliders 13 are slidably engaged with the slide rails 14 located directly below. A force transmission shaft 15 is fixedly installed at the lower corner of the placement frame 8. A motor 16 is installed on the base plate 1 and arranged on the same side as the force transmission shaft 15. A drum is fixedly mounted on the output shaft of the motor 16, and a force transmission rope is wound on the drum. The free end of the force transmission rope is fixedly connected to the force transmission shaft 15.

[0061] In this invention, the monitoring and control device calculates and analyzes the information obtained from the combustion surface monitoring device to obtain the position and speed of the combustion surface, and then controls the motor 16 to start. The output shaft of the motor 16 rotates and drives the drum on it to wind the force transmission rope. The gradually shortening force transmission rope drives the force transmission shaft 15 and the entire placement frame 8 to move towards the top cover 5. Its moving speed matches the combustion speed of the combustion surface. In this way, the physical field application device on the placement frame 8 can always apply the magnetic field and electric field to the combustion surface, that is, the primary combustion zone, thereby affecting the thrust of the solid fuel engine and realizing the adjustment of thrust.

[0062] In addition, a magnetic field application device is provided on the outside of the Laval nozzle 6. The magnetic field application device includes a support frame 17 that is fitted on the outside of the Laval nozzle 6 and fixed on the base plate 1. A cylindrical tube 18 fitted on the Laval nozzle 6 is hung inside the support frame 17. A coil 19 is wound on the cylindrical tube 18. The two ends of the coil 19 are respectively connected to the positive and negative poles of the power supply. A magnetic field is established by passing DC current through the coil 19, which can apply a stable magnetic field to the Laval nozzle 6.

[0063] The magnetic field application device can apply a magnetic field to the secondary combustion zone, which can affect the thrust of the solid propellant 7 and achieve thrust adjustment. The secondary combustion zone refers to the area where the throat and expansion section of the Laval nozzle 6 are located.

[0064] The cylindrical tube 18 is coaxial with the combustion chamber 4; when DC current is applied to the coil 19, the magnetic field strength and direction can be changed by changing the magnitude and direction of the current; and there are multiple sets of coils 19, each set of coils 19 is applied with a current of different intensities to achieve a gradually changing magnetic field (gradually increasing electric field, decreasing magnetic field).

[0065] The combustion surface monitoring device includes several resistors 22 connected in parallel via wires 21. The several resistors 22 are connected in series as a whole with a protective resistor 23, a power supply 24, and an ammeter 25. The distance between the nodes where each resistor 22 is connected to the wires 21 is equal. The several resistors 22, the protective resistor 23, the power supply 24, and the ammeter 25 are all installed in the integrated device 34, except for the wires 21.

[0066] The wire 21 is placed into the combustion chamber 4 together with the solid propellant 7, and the axis of the wire 21 is parallel to the axis of the combustion chamber 4. After the solid propellant 7 is ignited, the wire 21 located on the combustion surface is burned off, and the node connected to the resistor 22 is also burned off. The current cannot flow through the resistor 22, causing the current of the ammeter 25 to change. Since the distance between each node is equal, the combustion speed of the combustion surface can be obtained from the change of the ammeter 25 and the time interval between two changes. Then, the position of the combustion surface can be calculated from the magnitude of the current change.

[0067] In this invention, the combustion surface monitoring device causes changes in the ammeter 25 due to the combustion of the wire 21 and the node. The ammeter 25 transmits these changes to the computer 26 in the monitoring and control device via signals. The computer 26 calculates and analyzes the speed and position of the combustion surface, and then controls the rotation speed of the motor 16 based on the speed and position of the combustion surface. The motor 16 drives the placement frame 8 to track the combustion surface through the force transmission rope. In this way, the physical field application device on it can always apply magnetic and electric fields to the combustion surface to achieve thrust adjustment.

[0068] The computer 26 calculates and analyzes the combustion rate and location of the combustion surface, including the following steps:

[0069] Step S1: Let the length of the solid propellant 7 be L, the number of parallel resistors 22 be n, and the distance between each node of the parallel resistors 22 be equal, each being X:

[0070] ;

[0071] In the formula, L represents the length of the solid propellant, in meters; n represents the number of parallel resistors; and X represents the distance between two adjacent parallel resistor nodes, in meters.

[0072] Step S2: The time interval between changes in the ammeter reading 25 as combustion progresses is recorded as t. j (j=1,2,3,…n-1), then the velocity V of the burning surface at different nodes i (i=2,3,4…n) can be estimated as:

[0073] ;

[0074] In the formula, t j This indicates the time interval in seconds for the change in the ammeter reading (V). i The velocity of the combustion surface at different nodes, in meters per second;

[0075] Step S3: All parallel resistors 22 are equal, let's call them R. The protective resistor 23 is R0. Then, the magnitude of the current I0 before combustion begins is:

[0076] ;

[0077] In the formula, R represents the resistance value of parallel resistor 22, in ohms; R0 represents the resistance value of protective resistor 23, in ohms; and U represents the total voltage value of the circuit, in volts. This represents the electric current before combustion begins, measured in amperes.

[0078] The magnitude of the current when combustion reaches the a-th (a=1,2,3…n) node. for:

[0079] ;

[0080] The position S of the combustion surface can then be calculated as:

[0081] S = (a-1) * X.

[0082] The monitoring and control device includes a computer 26, and the integrated device 34 is electrically connected to the input terminal of the computer 26. The integrated device 34 transmits the current change signal to the computer 26 for calculating and analyzing the combustion speed and position of the combustion surface.

[0083] The monitoring and control device also includes a pressure tapping tube 27, a pressure transmitter 28, a thrust sensor 29, and a temperature sensor 30; a connecting hole 31 is provided on the expansion wall at the left end of the Laval nozzle 6, and a pressure tapping tube 27 is connected inside the connecting hole 31. The output end of the pressure tapping tube 27 is connected to the input end of the pressure transmitter 28, and the output end of the pressure transmitter 28 is electrically connected to the input end of the computer 26. The thrust sensor 29 and the temperature sensor 30 are installed on the side of the connecting hole 31, and the output ends of the thrust sensor 29 and the temperature sensor 30 are both electrically connected to the input end of the computer 26.

[0084] The monitoring and control device also includes a high-speed camera 32, which is installed on the side of the outlet of the Laval nozzle 6 at a height that is level with the axis of the combustion chamber 4, and is used to capture the shape of the flame at the outlet of the Laval nozzle 6; the output end of the high-speed camera 32 is electrically connected to the input end of the computer 26.

[0085] The output terminal of the computer 26 is electrically connected to the input terminal of the motor 16. The computer 26 can control the rotation speed of the motor 16 by the combustion speed and position of the combustion surface, thereby controlling the speed and position of the placement frame 8, so that the electric field and magnetic field on the placement frame 8 can always act on the combustion surface of the solid propellant.

[0086] In this invention, the pressure tube 27, thrust sensor 29, and temperature sensor 30 are installed on the Laval nozzle 6 to measure the pressure, thrust, and temperature when the flame is ejected, respectively. The high-speed camera 32 is used to capture the shape of the flame at the exit of the Laval nozzle 6. The pressure, thrust, temperature, and shape when the flame is ejected can reflect the influence of the physical field application device and the magnetic field application device on the combustion excitation of the solid propellant 7.

[0087] In addition, the lower right end face of the Laval nozzle 6 is fixedly connected to the left base 2, and the right end of the combustion chamber 4 is fixedly connected to a flange 33. The flange 33 is fixedly connected to the top cover 5 by bolts, and the lower end face of the flange 33 is fixedly connected to the right base 3.

[0088] The top cover 5 has a convex cross section, which can push the solid propellant 7 into the combustion chamber 4. The combustion chamber 4 is horizontally placed and made of a non-magnetic and high-temperature resistant material that can be penetrated by electric and magnetic fields.

[0089] This invention can apply electric and magnetic fields to the combustion surface (first-stage combustion region) of solid propellant 7 and track and control them, and apply magnetic field control to the throat and expansion section (second-stage combustion region) of Laval nozzle 6. It establishes an experimental device for bipolar control of rocket solid fuel engine with electric and magnetic field coupling, which can study the influence of electric and magnetic field coupling on the combustion excitation of solid propellant 7.

[0090] During the experiment, the solid propellant 7 was first determined according to the research requirements. Then, the solid propellant 7 and the wire 21 were pushed into the combustion chamber 4 through the top cover 5 and the top cover 5 was closed. Then, the solid propellant 7 was ignited using a laser igniter or an electric heating wire igniter, and the burning flame was ejected from the tail end of the Laval nozzle 6.

[0091] During the combustion of solid propellant 7, electric field excitation and / or magnetic field excitation are applied or not applied to the primary combustion zone according to research requirements, and magnetic field excitation is applied or not applied to the secondary combustion zone. The combustion temperature, pressure, thrust, and flame morphology changes are monitored and recorded by the monitoring and control device at the tail of the Laval nozzle 6 under different intensities and directions of electric field excitation and / or magnetic field excitation. After the solid propellant 7 has finished burning, the top cover 5 is opened, and then the solid propellant 7 and wire 21 are replaced. The top cover 5 is closed, and the intensity or direction of the electric field or magnetic field is changed for the next combustion experiment.

[0092] In the description of this invention, it should be understood that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0093] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for regulating solid propellant combustion by coupling electric and magnetic fields, characterized in that: Includes a base plate (1), on which a left base (2) and a right base (3) are fixedly installed. A combustion chamber (4) is fixedly installed on both the left base (2) and the right base (3). A top cover (5) is provided at the right end of the combustion chamber (4). A Laval nozzle (6) is fixedly connected to the left end of the combustion chamber (4) and is coaxially arranged with the combustion chamber (4). The interior of the combustion chamber (4) is filled with solid propellant (7) and a combustion surface monitoring device for tracking the combustion surface of the solid propellant (7). A displaceable physical field application device is provided on the outside of the combustion chamber (4) for applying various physical fields to the combustion surface. A drive assembly for displacing the physical field application device is installed on the base plate (1). It also includes a monitoring and control device for collecting data and calculating the position and speed of the combustion surface in the combustion chamber (4), and controlling the drive assembly to pull the physical field application device to displacement; The physical field application device includes a placement rack (8) fitted on the combustion chamber (4), a sleeve (9) fitted on the combustion chamber (4) is hung inside the placement rack (8), a coil (10) is wound on the sleeve (9), the two ends of the coil (10) are respectively connected to the positive and negative poles of the power supply, and a magnetic field is established by passing DC current through the coil (10), which can apply a stable magnetic field to the combustion chamber (4); a first set of electrode plates (11) is provided at the upper and lower ends of the placement rack (8), and the positive and negative poles of the DC high voltage power supply are respectively connected on the first set of electrode plates (11), and an electric field is established by applying voltage, which can apply an electric field in the vertical direction to the combustion chamber (4); a second set of electrode plates (12) is provided at the front and rear ends of the placement rack (8), and the positive and negative poles of the DC high voltage power supply are respectively connected on the second set of electrode plates (12), and an electric field is established by applying voltage, which can apply an electric field in the front and rear direction to the combustion chamber (4).

2. The solid propellant combustion device for electric field and magnetic field coupling regulation according to claim 1, characterized in that: The drive assembly includes sliders (13) fixed to the four corners of the lower end of the placement frame (8) and in the shape of an inverted U. Two slide rails (14) arranged in the same direction as the combustion chamber (4) are fixed on the base plate (1), and the sliders (13) are slidably engaged with the slide rails (14) located directly below. A force transmission shaft (15) is fixedly installed at the lower corner of the placement frame (8). A motor (16) is installed on the base plate (1) on the same side as the force transmission shaft (15). A drum is fixedly mounted on the output shaft of the motor (16), and a force transmission rope is wound on the drum. The free end of the force transmission rope is fixedly connected to the force transmission shaft (15).

3. The device for controlling solid propellant combustion by coupling electric and magnetic fields according to claim 1, characterized in that: A magnetic field application device is provided on the outside of the Laval nozzle (6). The magnetic field application device includes a shelf (17) which is fitted on the outside of the Laval nozzle (6) and fixed on the base plate (1). A cylindrical tube (18) fitted on the Laval nozzle (6) is hung inside the shelf (17). A coil (19) is wound on the cylindrical tube (18). The two ends of the coil (19) are respectively connected to the positive and negative poles of the power supply. A magnetic field is established by passing DC current through the coil (19), which can apply a stable magnetic field to the Laval nozzle (6).

4. The solid propellant combustion device for electric field and magnetic field coupling regulation according to claim 3, characterized in that: The sleeve (9) and the cylindrical tube (18) are both coaxial with the combustion chamber (4); when DC current is applied to coil one (10) and coil two (19), the magnetic field strength and direction can be changed by changing the magnitude and direction of the current; and there are multiple sets of coil one (10) and coil two (19), with each set of coil one (10) being supplied with a current of different intensities to achieve a gradual magnetic field; each set of coil two (19) is supplied with a current of different intensities to achieve a gradual magnetic field; The first group of electrode plates (11) and the second group of electrode plates (12) both include positive electrode plates and negative electrode plates. The positive electrode plates and negative electrode plates are fixed on the placement frame (8) by connecting rods (20), and the positive electrode plates and negative electrode plates can be interchanged to change the direction of the electric field, and the electric field strength can be changed by changing the magnitude of the current and voltage.

5. The solid propellant combustion device for electric field and magnetic field coupling regulation according to claim 3, characterized in that: The combustion surface monitoring device includes several resistors (22) connected in parallel via wires (21). The several resistors (22) are connected in series as a whole with a protective resistor (23), a power supply (24), and an ammeter (25). The distance between the nodes connecting each resistor (22) to the wires (21) is equal. The several resistors (22), the protective resistor (23), the power supply (24), and the ammeter (25) are all installed in the integrated device (34), except for the wires (21). The wire (21) and the solid propellant (7) are placed into the combustion chamber (4) together, and the axis of the wire (21) is parallel to the axis of the combustion chamber (4). After the solid propellant (7) is ignited, the wire (21) located on the combustion surface is burned off, and the node connected to the resistor (22) is also burned off. The current cannot flow through the resistor (22), causing the current of the ammeter (25) to change. Since the distance between each node is equal, the combustion speed of the combustion surface can be obtained according to the change of the ammeter (25) and the time interval between each change. Then, the position of the combustion surface can be calculated according to the magnitude of the current change.

6. The device for controlling solid propellant combustion by coupling electric and magnetic fields according to claim 5, characterized in that: The monitoring and control device includes a computer (26), and the integrated device (34) is electrically connected to the input terminal of the computer (26). The integrated device (34) transmits the current change signal to the computer (26) for calculating and analyzing the combustion speed and position of the combustion surface. The monitoring and control device also includes a pressure tap (27), a pressure transmitter (28), a thrust sensor (29), and a temperature sensor (30); a connecting hole (31) is provided on the expansion wall of the left end of the Laval nozzle (6), and a pressure tap (27) is connected in the connecting hole (31). The output end of the pressure tap (27) is connected to the input end of the pressure transmitter (28), and the output end of the pressure transmitter (28) is electrically connected to the input end of the computer (26). A thrust sensor (29) and a temperature sensor (30) are installed on the side of the connecting hole (31), and the output ends of the thrust sensor (29) and the temperature sensor (30) are both electrically connected to the input end of the computer (26). The monitoring and control device also includes a high-speed camera (32), which is installed on the side of the outlet of the Laval nozzle (6) at a height that is level with the axis of the combustion chamber (4) and is used to capture the shape of the flame at the outlet of the Laval nozzle (6); the output end of the high-speed camera (32) is electrically connected to the input end of the computer (26); The output of the computer (26) is electrically connected to the input of the motor (16). The computer (26) can control the rotation speed of the motor (16) by the combustion speed and position of the combustion surface, thereby controlling the speed and position of the placement rack (8) so that the electric field and magnetic field on the placement rack (8) can always act on the combustion surface of the solid propellant.

7. The device for controlling solid propellant combustion by coupling electric and magnetic fields according to claim 6, characterized in that: The computer (26) calculates and analyzes the combustion rate and location of the combustion surface, including the following steps: Step S1: Let the length of the solid propellant (7) be L, the number of parallel resistors (22) be n, and the distance between each node of the parallel resistors (22) be equal, all being X: ； In the formula, L represents the length of the solid propellant, in meters; n represents the number of parallel resistors; and X represents the distance between two adjacent parallel resistor nodes, in meters. Step S2: As combustion proceeds, the time interval between changes in the ammeter (25) value is recorded as t. j (j=1,2,3,…n-1), then the velocity V of the burning surface at different nodes i (i=2,3,4…n) can be estimated as: ； In the formula, t j This indicates the time interval of the change in the ammeter (25) value, in seconds; V i The velocity of the combustion surface at different nodes, in meters per second; Step S3: If all parallel resistors (22) are equal and set as R, and the protective resistor (23) is R0, then the current I0 before combustion begins is: ； In the formula, R represents the resistance value of the parallel resistor (22), in ohms; R0 represents the resistance value of the protective resistor (23), in ohms; and U represents the total voltage value of the circuit, in volts. This represents the electric current before combustion begins, measured in amperes. The magnitude of the current when combustion reaches the a-th (a=1,2,3…n) node. for: ； The position S of the combustion surface can then be calculated as: S = (a-1) * X.

8. The solid propellant combustion device for electric field and magnetic field coupling regulation according to claim 1, characterized in that: The lower right end face of the Laval nozzle (6) is fixedly connected to the left base (2), and the right end of the combustion chamber (4) is fixedly connected to a flange (33). The flange (33) is fixedly connected to the top cover (5) by bolts, and the lower end face of the flange (33) is fixedly connected to the right base (3).

9. The device for controlling solid propellant combustion by coupling electric and magnetic fields according to claim 1, characterized in that: The top cover (5) has a convex cross section, which can push the solid propellant (7) into the combustion chamber (4). The combustion chamber (4) is horizontally placed and made of a non-magnetic and high-temperature resistant material that can be penetrated by electric and magnetic fields.

Images