Microwave generation device, equipment and method for microwave ignition

Abstract

The invention relates to the technical field of microwave ignition, in particular to a microwave generation device, equipment and method for microwave ignition, and the microwave generation device comprises a microwave source, a resonant cavity and a microwave probe; the microwave source serves as an energy source, and single-frequency continuous waves are fed into the resonant cavity through the microwave probe. The resonant cavity receives single-frequency continuous waves, and resonance is generated to collect energy; when the resonant cavity resonates, the position of an electromagnetic wave antinode is located on the microwave probe. And the microwave probe is used for secondarily focusing energy gathered in the resonant cavity on the solid energetic material to be ignited. According to the device, through the cooperative focusing effect of the resonant cavity and the microwave probe, the local field intensity is rapidly improved, the energy transfer path is shortest, the loss is minimum, the energy utilization rate and the ignition efficiency are greatly improved, and the problems that in the prior art, microwave ignition cannot achieve full utilization of energy, and the ignition efficiency is low are solved. And the problems of high excitation power, high energy consumption, low ignition efficiency and poor safety are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave ignition, and specifically to a microwave generating device, equipment and method for microwave ignition, and in particular to a high-field-strength microwave generating device, equipment and method for microwave ignition. Background Art

[0002] Microwave ignition is an important way to ignite solid energetic materials. It uses electromagnetic waves in the frequency range of 300MHz to 300GHz to heat solid energetic materials to their ignition point and initiate the ignition process. As a non-contact ignition method, microwave ignition technology has the advantages of high directivity, fast heating rate, and high controllability, and is widely used in internal combustion engines, solid rocket engines, industrial heating, and combustion control.

[0003] The thermal effect of microwaves is related to the dielectric properties of the materials used. Since the thermal effect of microwave ignition is mainly achieved through the absorption of microwave energy by the material, for solid energetic materials with low dielectric constants and poor wave absorption performance such as small-grain black powder, and insensitive solid energetic materials with strong heat resistance and low thermal sensitivity, microwave energy is difficult to be effectively converted into thermal energy, and it is difficult to reach the temperature threshold required for ignition under conventional microwave field strength, resulting in low ignition efficiency. In order to overcome the problem of poor wave absorption performance of materials, ignition can only be completed under the action of extremely high field strength, and the output power of the microwave source needs to be greatly increased without changing the original microwave ignition device. For example, the Chinese invention with publication number CN112945032A discloses a microwave ignition device for artillery, which uses a coaxial resonant cavity as a microwave ignition cavity, which is filled with gunpowder medium, and the outer conductor of the coaxial resonant cavity is provided with evenly distributed through holes, which are used to allow the flame after igniting the gunpowder to be uniformly ejected from the through holes, so as to achieve the purpose of igniting the propellant at multiple points at the same time. The device utilizes the focusing effect of the electric field in the cavity when the resonant cavity resonates to achieve microwave ignition of solid energetic materials. However, the above-mentioned ignition device cannot fully utilize the energy fed by the microwave source, and still requires an ignition source greater than 3000W to achieve microwave ignition. This not only increases energy consumption and reduces the economy and practicality of the system, but the use of high-power microwave sources can easily cause accidental ignition or equipment overheating, posing a safety hazard.

[0004] Therefore, it is necessary to study a microwave ignition technology that produces high field strength under low-power excitation, so as to achieve effective and rapid ignition of solid energetic materials with high ignition field strength threshold, so as to meet the ignition requirements of high-energy and high-safety scenarios. Summary of the invention

[0005] In view of the problem in the prior art that microwave ignition cannot fully utilize energy, resulting in high excitation power, large energy consumption, low ignition efficiency and poor safety, the present invention provides a microwave generating device, equipment and method for microwave ignition.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a microwave generating device for microwave ignition, comprising a microwave source, a resonant cavity and a microwave probe; The microwave source is used as an energy source to feed a single-frequency continuous wave into the resonant cavity through a microwave probe; The resonant cavity receives a single-frequency continuous wave and resonates to collect energy; wherein, when the resonant cavity resonates, the antinode of the electromagnetic wave is located on the microwave probe; The microwave probe performs secondary focusing of the energy collected inside the resonant cavity onto the solid energetic material to be ignited.

[0007] Optionally, a radio frequency isolator is provided between the microwave source and the microwave probe.

[0008] Optionally, the microwave source and the radio frequency isolator are connected via a coaxial cable.

[0009] Optionally, the resonant cavity is a square resonant cavity.

[0010] Optionally, a vertex of the resonant cavity is taken as the coordinate origin, and the long side of the resonant cavity is taken as x Axis direction, with the short side of the resonant cavity as y Axis direction, with the height of the resonant cavity as z A rectangular coordinate system is established in the direction of the axis; the relationship between the resonant frequency of the resonant cavity and the structural parameters of the resonant cavity is:

[0011] in, is the resonant frequency; is the speed of light in vacuum; is the resonant wave number of the resonant cavity; is the relative magnetic permeability of the medium in the resonant cavity; is the relative dielectric constant of the medium in the resonant cavity; for x The number of standing waves in the axial direction, for y The number of standing waves in the axial direction, for z The number of standing waves in the axial direction, is the length of the long side of the resonant cavity, is the short side length of the resonant cavity, is the height of the resonant cavity.

[0012] Optionally, a metal storage platform is provided inside the resonant cavity, and the metal storage platform is located below the microwave probe.

[0013] Optionally, the end of the microwave probe is a needle tip structure, and the angle between the cone surface of the needle tip and the axis of the microwave probe is 15°.

[0014] Optionally, observation windows are provided on both sides of the resonance cavity, and cutoff waveguides are provided at the observation windows, and a cutoff frequency of the cutoff waveguide is greater than the highest frequency of the electromagnetic wave in the resonance cavity.

[0015] A microwave ignition device comprises the microwave generating device for microwave ignition.

[0016] A microwave ignition method using the microwave generating device comprises: Feeding a single-frequency continuous wave into the resonant cavity to make the resonant cavity resonate and collect energy into the resonant cavity; The energy collected inside the resonant cavity is secondarily focused onto the solid energetic material to be ignited to achieve ignition.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a microwave generating device for microwave ignition, including a microwave source, a resonant cavity and a microwave probe. The microwave source is used as an energy source, and a single-frequency continuous wave is fed into the resonant cavity through the microwave probe as an energy transmission medium; the resonant cavity is used to resonate to collect energy, and finally the collected energy is secondary focused by the microwave probe to form a local high-intensity electric field area, which directly acts on the surface of the solid energetic material to achieve low-power excitation ignition. This ignition method can achieve a local field strength of MV / m at an excitation power of ~10W through the synergistic focusing effect of the resonant cavity and the microwave probe, reducing the energy loss during the transmission process and greatly improving the energy utilization rate; when the resonant cavity resonates, the antinode of the electromagnetic wave is located on the microwave probe, the energy transfer path is the shortest and the loss is the least, ensuring that the energy can be efficiently transferred to the surface of the solid energetic material, further improving the ignition efficiency and reducing energy loss. Compared with existing devices, the microwave generating device for microwave ignition provided by the present invention has greatly reduced microwave excitation power required to produce the same field intensity, has the characteristics of low energy consumption, high efficiency and high safety, and has broad application prospects in the fields of military, aerospace, industrial blasting, etc.

[0018] A radio frequency isolator is provided between the microwave source and the microwave probe, and the radio frequency isolator allows microwave energy to be transmitted unidirectionally from the microwave source to the microwave probe, and guides the reflected wave to the absorption port of the isolator to prevent the reflected wave from returning to the microwave source, thereby avoiding unstable output power of the microwave source and damage to the microwave source caused by the reflected wave, and improving the stability and service life of the microwave source The microwave source and the radio frequency isolator are connected via a coaxial cable, which can effectively shield external interference and reduce the loss of microwave energy during transmission.

[0019] The resonant cavity is a square resonant cavity, which supports multiple electromagnetic modes and transverse magnetic field modes. By reasonably designing the cavity size, the excitation and energy distribution of a specific mode can be optimized, which is helpful to achieve efficient focusing and transmission of microwave energy. By obtaining the relationship between the resonant frequency of the resonant cavity and the structural parameters of the resonant cavity, the resonant frequency is accurately controlled to ensure efficient transmission and concentration of microwave energy in the cavity, and the energy can be more efficiently focused on the target area, thereby improving energy utilization and high space utilization, and can adapt to different microwave sources and ignition requirements.

[0020] A metal placement table is arranged inside the resonant cavity and is located below the microwave probe. The arrangement of the metal placement table can not only provide a placement point and necessary support for solid energetic materials, but also further compress the electric field distribution space during resonance, making the electric field energy concentration area smaller and closer to the microwave probe, thereby shortening the energy focusing ignition time and improving the ignition success rate.

[0021] The end of the microwave probe is a needle tip structure, and the angle between the needle tip cone and the axis of the microwave probe is 15°; the design of the needle tip structure enables the microwave energy to form a local high-intensity electric field area at the end of the probe, and the 15° cone angle can effectively guide the microwave energy to concentrate on the target area, reduce energy diffusion, significantly improve energy density, make it easier for energetic materials to reach the ignition temperature, shorten the ignition time, and improve the ignition success rate.

[0022] Observation windows are provided on both sides of the resonant cavity, and cutoff waveguides are arranged at the observation windows. The cutoff frequency of the cutoff waveguide is greater than the highest frequency of the electromagnetic wave in the resonant cavity. The cutoff waveguide can effectively prevent the radiation field leakage from causing damage to the equipment.

[0023] A microwave ignition device comprises the microwave generating device for microwave ignition. It is detected that the generating device has multiple operating frequencies in the range of 2 to 3 GHz, and the field strength can reach MV / m level under an excitation power of ~10W, thereby realizing efficient transmission, focusing and utilization of microwave energy. It has the advantages of efficient energy utilization, low power consumption, high safety, high ignition accuracy, wide applicability and structural strength, and provides important support for the further development and optimization of microwave ignition technology.

[0024] A microwave ignition method using the microwave generating device described above, wherein the method feeds a single-frequency continuous wave into a resonant cavity to cause the resonant cavity to resonate and collect energy into the resonant cavity; the energy collected inside the resonant cavity is secondarily focused onto a solid energetic material to be ignited, thereby achieving rapid ignition. The method is simple, easy to operate, and has good safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a schematic structural diagram of a microwave generating device for microwave ignition.

[0026] Figure 2 A rectangular resonant cavity TE of a microwave generating device for microwave ignition of the present invention m0l Graph of the electric field variation in the resonant mode.

[0027] Figure 3 It is a simulation diagram of a microwave generating device for wave ignition in an embodiment of the present invention, wherein a is an electric field distribution diagram, and b is an electric field intensity diagram at the end of a microwave probe.

[0028] Figure 4 The present invention is a flow chart of an ignition method using a microwave generating device.

[0029] Among them, 1-microwave source, 2-resonant cavity, 3-microwave probe, 4-RF isolator, 5-coaxial cable, 6-metal storage platform, 7-cutoff waveguide. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0033] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0034] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0035] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0037] Example 1 See also Figure 1 , the present invention discloses a microwave generating device for microwave ignition, comprising a microwave source 1, a resonant cavity 2 and a microwave probe 3; The microwave source 1 serves as an energy source, and feeds a single-frequency continuous wave into the resonant cavity 2 through a microwave probe 3; the resonant cavity 2 receives the single-frequency continuous wave, resonates, and collects energy; wherein, when the resonant cavity 2 resonates, the antinode of the electromagnetic wave is located on the microwave probe 3; the microwave probe 3 performs secondary focusing of the energy collected inside the resonant cavity 2 onto the solid energetic material to be ignited.

[0038] The device uses a microwave source 1 as an energy source to provide a continuous single-frequency continuous wave for the resonant cavity 2; the resonant cavity 2 resonates to collect energy, and the collected energy is secondary focused by the microwave probe 3 to form a local high-intensity electric field area, which directly acts on the surface of the solid energetic material to achieve low-power excitation ignition. This ignition method can achieve a local field strength of MV / m at an excitation power of ~10W through the coordinated focusing effect of the resonant cavity and the microwave probe, reducing the loss of energy during transmission and greatly improving the utilization rate of energy. It has the characteristics of low energy consumption, high efficiency and high safety, and has broad application prospects in the fields of military, aerospace, industrial blasting, etc.

[0039] Example 2 See also Figure 1 , the present invention provides a microwave generating device for microwave ignition, comprising a microwave source 1, a resonant cavity 2, a microwave probe 3, a radio frequency isolator 4 and a coaxial cable 5; The microwave source 1 is used as an energy source to provide energy for the entire device; the single-frequency continuous wave output end of the microwave source 1 is connected to the coaxial cable 5, the radio frequency isolator 4 and the microwave probe 3 in sequence; The microwave probe 3 is located in the resonant cavity 2 and acts as a medium to feed a single-frequency continuous wave into the resonant cavity 2; the radio frequency isolator 4 is used to prevent the energy reflected by the resonant cavity 2 from damaging the microwave source 1; The microwave source 1 and the radio frequency isolator 4 are connected via a coaxial cable 5, which can effectively shield external interference and reduce the loss of microwave energy during transmission; When in use, the microwave source 1 is turned on to output a single-frequency continuous wave, which is then fed continuously into the resonant cavity 2 via the coaxial cable 5, the RF isolator 4 and the microwave probe 3 to generate resonance, and the energy is gathered near the microwave probe 3. Through the secondary focusing of the microwave probe 3, the energy is focused onto the solid energetic material to achieve efficient and rapid ignition. The device has the advantages of simple structure, easy operation, low energy consumption and good safety, and can be applied to microwave ignition in a variety of scenarios.

[0040] Example 3 See also Figure 1 The present invention provides a microwave generating device for microwave ignition, comprising a microwave source 1, wherein the microwave source 1 is sequentially connected to a coaxial cable 5, a radio frequency isolator 4 and a microwave probe 3, wherein a resonant cavity 2 is arranged below the microwave probe 3, wherein the resonant cavity 2 is a square resonant cavity, wherein a metal storage platform 6 is arranged inside the resonant cavity 2; and the microwave probe 3 is inserted into the resonant cavity 2; See also Figure 2The designed resonant cavity 2 is composed of a rectangular waveguide section with two short-circuited ends. The resonant frequency reflects the steady-state oscillation law of the electric field energy and magnetic field energy conservation in the resonant cavity 2, and is the frequency at which the electric field energy and magnetic field energy in the cavity are completely converted periodically. In order to clarify the relationship between the resonant frequency and the cavity structure parameters of the resonant cavity 2, a rectangular coordinate system is established in the rectangular resonant cavity, with a vertex of the resonant cavity 2 as the coordinate origin and the long side of the resonant cavity 2 as the coordinate system. x Axis direction, with the short side of the resonant cavity 2 as y Axis direction, with the height of the resonant cavity 2 as z Axis direction, a rectangular coordinate system is established; the relationship between the resonant frequency of the resonant cavity 2 and the structural parameters of the resonant cavity 2 is:

[0041] in, is the resonant frequency; is the speed of light in vacuum; is the resonant wave number of resonant cavity 2; is the relative magnetic permeability of the medium in the resonant cavity 2; is the relative dielectric constant of the medium in the resonant cavity 2; for x The number of standing waves in the axial direction, for y The number of standing waves in the axial direction, for z The number of standing waves in the axial direction, is the length of the long side of the resonant cavity 2, is the short side length of the resonant cavity 2, is the height of resonant cavity 2.

[0042] It can be seen that by reasonably designing the cavity size, the excitation and energy distribution of a specific mode can be optimized, which is helpful to achieve efficient focusing and transmission of microwave energy. By obtaining the relationship between the resonant frequency of the resonant cavity and the structural parameters of the resonant cavity 2, the resonant frequency can be accurately controlled to ensure efficient transmission and concentration of microwave energy in the resonant cavity 2. The energy can be more efficiently focused on the target area, the energy utilization rate is improved, and the space utilization rate is high, which can be adapted to different microwave sources and ignition requirements.

[0043] The setting of the metal placement table 6 can not only provide a placement point and necessary support for the solid energetic material, but also further compress the electric field distribution space during resonance, making the electric field energy concentration area smaller and closer to the microwave probe 3, shortening the energy focusing ignition time and improving the ignition success rate.

[0044] The metal storage table 6 is not limited in form. A flat metal plate can be used as the storage table, and the surface can be polished or plated to improve the microwave reflection efficiency; the surface of the storage table can also be designed to be concave to enhance the focusing effect of microwave energy, and the shape of the concave surface can be optimized according to the position of the microwave probe and the energy distribution requirements; the metal storage table 6 can be flat, concave reflective, multi-level reflective, grid-shaped and adjustable, etc. By reasonably selecting materials, optimizing structures and surface treatments, the focusing effect of microwave energy, ignition efficiency and system safety can be significantly improved. In practical applications, the most suitable metal storage table form should be selected according to the specific scene requirements to achieve the best ignition effect and system performance.

[0045] Example 4 See also Figure 1 The present invention provides a microwave generating device for microwave ignition, comprising a microwave source 1, wherein the power range of the microwave source 1 is 0 to 100 W, the microwave source 1 is sequentially connected to a coaxial cable 5, a radio frequency isolator 4 and a microwave probe 3, a resonant cavity 2 is arranged below the microwave probe 3, the resonant cavity 2 is a square resonant cavity, a metal storage table 6 is arranged inside the resonant cavity 2; the microwave probe 3 is inserted into the resonant cavity 2; when the resonant cavity 2 resonates, the antinode of the electromagnetic wave is located on the microwave probe 3; The microwave probe 3 needle tip structure has an angle of 15° between the needle tip cone and the axis of the microwave probe 3, the distance between the microwave probe 3 and the metal stand 6 is 1 to 5 mm, and the radius of the microwave probe 3 is greater than or equal to 2.5 mm; the parameters are optimized through simulation so that the electric field energy in the cavity 2 is concentrated in the area between the microwave probe 3 and the metal stand 6 for placing solid energetic materials during resonance; See also Figure 2 The designed resonant cavity 2 is composed of a rectangular waveguide section with two short-circuited ends. The resonant frequency reflects the steady-state oscillation law of the electric field energy and magnetic field energy conservation in the resonant cavity 2, and is the frequency at which the electric field energy and magnetic field energy in the cavity are completely converted periodically. In order to clarify the relationship between the resonant frequency and the cavity structure parameters of the resonant cavity 2, a rectangular coordinate system is established in the rectangular resonant cavity, with a vertex of the resonant cavity 2 as the coordinate origin and the long side of the resonant cavity 2 as the coordinate system. x Axis direction, with the short side of the resonant cavity 2 as y Axis direction, with the height of the resonant cavity 2 as z Axis direction, a rectangular coordinate system is established; the relationship between the resonant frequency of the resonant cavity 2 and the structural parameters of the resonant cavity 2 is:

[0046] in, is the resonant frequency; is the speed of light in vacuum; is the resonant wave number of resonant cavity 2; is the relative magnetic permeability of the medium in the resonant cavity 2; is the relative dielectric constant of the medium in the resonant cavity 2; for x The number of standing waves in the axial direction, for y The number of standing waves in the axial direction, for z The number of standing waves in the axial direction, is the length of the long side of the resonant cavity 2, is the short side length of the resonant cavity 2, is the height of resonant cavity 2.

[0047] Observation windows are provided on both sides of the resonant cavity 2, and a cutoff waveguide 7 is provided at the observation window, and the cutoff frequency of the cutoff waveguide 7 is greater than the highest frequency of the electromagnetic wave in the resonant cavity 2, and the cutoff waveguide 7 is used to effectively prevent the radiation field leakage from causing damage to the equipment; the proposed observation window is a circular observation window, and a circular waveguide tube with an inner diameter the same as the observation window radius is used as the cutoff waveguide 7 to prevent the radiation field leakage from causing damage to the equipment. If the highest frequency of the electromagnetic wave in the resonant cavity 2 is less than the cutoff frequency of the cutoff waveguide, the intensity of the electromagnetic wave decays exponentially when it propagates outward through the cutoff waveguide:

[0048] in, is the electric field strength of the electromagnetic wave in the resonant cavity 2 before entering the cutoff waveguide 7; is the distance the electromagnetic wave propagates in the cutoff waveguide, The field strength of the electromagnetic wave at this time is is the attenuation constant of electromagnetic waves propagating in the cutoff waveguide 7. It can be seen that the longer the cutoff waveguide 7 is, the higher the attenuation capacity of electromagnetic waves is. However, an overly long cutoff waveguide 7 is not conducive to the observation and recording of the ignition phenomenon in the resonant cavity 2, and the observation window will lose its original meaning. In the design, the appropriate length of the dielectric waveguide 7 can be designed according to the electromagnetic compatibility requirements and observation needs.

[0049] The device uses a microwave probe 3 to feed the resonant cavity 2. By reasonably selecting the resonant mode of the resonant cavity 2 and setting the connection point between the microwave probe 3 and the resonant cavity 2 as the center of the upper surface, the electric field energy is gathered near the microwave probe area during resonance; a metal storage table 6 is further set below the microwave probe 3 to place solid energetic materials and compress the electric field distribution space during resonance, so that the electric field energy gathering area is smaller and closer to the probe; the end of the microwave probe 3 is designed to be a needle tip structure, the probe radius is not less than 2.5 mm, and the angle between the cone and the axis is 15°. The electric field energy distributed near the probe during resonance is concentrated at the tip of the microwave probe 3 through the distortion effect of the metal tip on the electric field; on the basis of ensuring that the front end of the microwave probe 3 is 1 to 5 mm apart from the metal storage table 6, the parameter fine-tuning optimization design is performed to make the antinode position of the electromagnetic wave at the resonance be at the probe position, further improve the maximum field strength, complete the secondary focusing of the energy in the cavity, and achieve ignition.

[0050] To further illustrate the beneficial effects of the microwave generating device for microwave ignition provided by the present invention, a resonance cavity 2 in a certain device is designed to be 170 mm long, 150 mm wide and 150 mm high, a microwave probe 3 is 51 mm long, a maximum radius of the needle tip is 2.5 mm, an angle between the needle tip cone and the axis is 15°, and a distance of 2 mm between the needle tip and the metal stand is 2 mm. Simulation is performed under 25 W power excitation. Figure 3 The simulation results show that the maximum field strength generated under 25W power excitation exceeds 7MV / m. It can be seen that the device has multiple operating frequencies in the range of 2 to 3GHz, and the field strength can reach MV / m at a power level of ~10W. Compared with existing devices, the microwave excitation power required to generate the same field strength is greatly reduced.

[0051] A microwave ignition device comprises the microwave generating device for microwave ignition. It is detected that the generating device has multiple operating frequencies in the range of 2 to 3 GHz, and the field strength can reach MV / m level under an excitation power of ~10W, thereby realizing efficient transmission, focusing and utilization of microwave energy. It has the advantages of efficient energy utilization, low power consumption, high safety, high ignition accuracy, wide applicability and structural strength, and provides important support for the further development and optimization of microwave ignition technology.

[0052] See also Figure 4 The present invention also provides a microwave ignition method using the microwave generating device, comprising: S1: Feed a single-frequency continuous wave into the resonant cavity 2 to make the resonant cavity 2 resonate and collect energy into the resonant cavity 2; S2: The energy collected inside the resonance cavity 2 is secondarily focused onto the solid energetic material to be ignited to achieve ignition.

[0053] The method is simple, easy to operate and safe.

[0054] In summary, the present invention provides a microwave generating device, equipment and method for microwave ignition, including a resonant cavity 2, a microwave probe 3, a metal placement table 6 and a cutoff waveguide 7. The device uses a solid-state microwave source 1 with a power range of 0 to 100W as an energy source, feeds a single-frequency continuous wave into the microwave ignition cavity through a radio frequency isolator 4, and the resonant cavity 2 is coupled with an external circuit through a microwave probe 3. When the microwave frequency fed into the resonant cavity 2 by the microwave source 1 causes the resonant cavity 2 to resonate, the energy in the resonant cavity 2 is concentrated in the middle of the cavity, and further utilizes the distortion effect of the front end needle tip structure of the microwave probe 3 on the electric field and the compression effect of the metal placement table on the electric field distribution space to perform secondary focusing on the electric field in the cavity, and forms a region with extremely high electric field strength at the place where the solid energetic material is placed on the metal placement table 6, so as to realize microwave ignition of the solid energetic material. Compared with the prior art, the device has the characteristics of high energy utilization, low energy consumption, good safety, high ignition efficiency, etc., and can be widely used in military, aerospace, industrial blasting and other fields.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and substitutions, and these modifications and substitutions are also within the scope of protection covered by the claims.

Claims

1. A microwave generating device for microwave ignition, characterized in that: It comprises a microwave source (1), a resonant cavity (2) and a microwave probe (3); The microwave source (1) serves as an energy source and feeds a single-frequency continuous wave into the resonant cavity (2) through a microwave probe (3); The resonant cavity (2) receives a single-frequency continuous wave and resonates to collect energy; wherein, when the resonant cavity (2) resonates, the antinode of the electromagnetic wave is located on the microwave probe (3); The microwave probe (3) performs secondary focusing of the energy collected inside the resonant cavity (2) onto the solid energetic material to be ignited.

2. The microwave generating device for microwave ignition according to claim 1, characterized in that: A radio frequency isolator (4) is provided between the microwave source (1) and the microwave probe (3).

3. The microwave generating device for microwave ignition according to claim 2, characterized in that: The microwave source (1) and the radio frequency isolator (4) are connected via a coaxial cable (5).

4. The microwave generating device for microwave ignition according to claim 1, characterized in that: The resonant cavity (2) is a square resonant cavity.

5. The microwave generating device for microwave ignition according to claim 4, characterized in that: Take a vertex of the resonant cavity (2) as the coordinate origin and the long side of the resonant cavity (2) as x axial direction, with the short side of the resonant cavity (2) as y axial direction, with the height of the resonant cavity (2) as z A rectangular coordinate system is established in the axial direction; the relationship between the resonant frequency of the resonant cavity (2) and the structural parameters of the resonant cavity (2) is: in, is the resonant frequency; is the speed of light in vacuum; is the resonant wave number of the resonant cavity (2); is the relative magnetic permeability of the medium in the resonant cavity (2); is the relative dielectric constant of the medium in the resonant cavity (2); for x The number of standing waves in the axial direction, for y The number of standing waves in the axial direction, for z The number of standing waves in the axial direction, is the length of the long side of the resonant cavity (2), is the short side length of the resonant cavity (2), is the height of the resonant cavity (2).

6. The microwave generating device for microwave ignition according to claim 1, characterized in that: A metal storage platform (6) is provided inside the resonant cavity (2), and the metal storage platform (6) is located below the microwave probe (3).

7. The microwave generating device for microwave ignition according to claim 1, characterized in that: The end of the microwave probe (3) is a needle tip structure, and the angle between the needle tip cone surface and the axis of the microwave probe (3) is 15°.

8. The microwave generating device for microwave ignition according to claim 1, characterized in that: Observation windows are provided on both sides of the resonant cavity (2), and cutoff waveguides (7) are provided at the observation windows, and the cutoff frequency of the cutoff waveguide (7) is greater than the highest frequency of the electromagnetic waves in the resonant cavity (2).

9. A microwave ignition device, characterized in that: The invention comprises a microwave generating device for microwave ignition as described in any one of claims 1 to 8.

10. A microwave ignition method using the microwave generating device according to any one of claims 1 to 8, characterized in that: include: Feeding a single-frequency continuous wave into the resonant cavity (2) to cause the resonant cavity (2) to resonate and collect energy into the resonant cavity (2); The energy collected inside the resonant cavity (2) is secondarily focused onto the solid energetic material to be ignited, thereby achieving ignition.

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