Microwave feed system

Abstract

The utility model provides a microwave feed system. The microwave feed system comprises a waveguide excitation cavity, a rectangular waveguide, a rectangular resonant cavity, a dielectric waveguide and a microwave reaction cavity. The rectangular waveguide is respectively connected with the waveguide excitation cavity and the rectangular resonant cavity, and the bottom of the rectangular waveguide is parallel to the bottom of the rectangular resonant cavity; an opening is formed in the top of the rectangular resonant cavity; the dielectric waveguide is arranged in the opening; the microwave reaction cavity is arranged above the rectangular resonant cavity; the waveguide excitation cavity is used for converting the mode of the received microwave into a mode in which the rectangular waveguide can propagate, feeding the microwave into the rectangular waveguide, feeding the microwave into the rectangular resonant cavity through the rectangular waveguide, performing mode integration through the rectangular resonant cavity, and feeding the microwave reaction cavity through the dielectric waveguide; according to the utility model, the rectangular waveguide and the rectangular resonant cavity are combined between the microwave reaction cavity and the microwave source for feeding, so that the problem of low feeding efficiency of the existing feeding system is solved, and the antenna has the advantages of being easy to process and install.

Description

Technical Field

[0001] The utility model relates to the field of physics, in particular to a microwave heating technology, in particular to a microwave reactor, and specifically to a microwave feeding system. Background Art

[0002] The existing feeding method of microwave reactor adopts the following method: the microwave source antenna is directly fed into the microwave reaction cavity. This method has the following problems: it is easily affected by the materials in the microwave reaction cavity, resulting in low feeding efficiency. Utility Model Content

[0003] The purpose of the utility model is to provide a microwave feeding system for solving the problems pointed out in the above background technology.

[0004] The utility model provides a microwave feeding system, which comprises: a waveguide excitation cavity, a rectangular waveguide, a rectangular resonant cavity, a dielectric waveguide and a microwave reaction cavity; one end of the rectangular waveguide is connected to the waveguide excitation cavity, the other end of the rectangular waveguide is connected to the rectangular resonant cavity, and the bottom of the rectangular waveguide is parallel to the bottom of the rectangular resonant cavity; an opening is arranged on the top of the rectangular resonant cavity; the dielectric waveguide is arranged in the opening; the microwave reaction cavity is arranged above the rectangular resonant cavity; the waveguide excitation cavity is used for converting the mode of the received microwave into a mode that the rectangular waveguide can propagate, and then feeding it into the rectangular waveguide, and then feeding it into the rectangular resonant cavity through the rectangular waveguide, and then feeding it into the microwave reaction cavity through the dielectric waveguide after mode integration in the rectangular resonant cavity; the difference between the resonant frequency in the rectangular resonant cavity and the frequency of the microwave meets a preset condition.

[0005] In the utility model, a rectangular waveguide and a rectangular resonant cavity are combined between the microwave reaction cavity and the microwave source, and power feeding is performed by exciting the resonant state of the rectangular resonant cavity, which effectively solves the problem of low power feeding efficiency caused by directly feeding the microwave source into the microwave reaction cavity in the prior art. In addition, the rectangular resonant cavity has the advantages of easy processing and installation, and convenient adjustment of the power feeding efficiency.

[0006] In an implementation of the utility model, the size of the rectangular resonant cavity is determined by simulation so that the rectangular resonant cavity works in a target state to improve the feeding efficiency of the microwave feeding system.

[0007] In this implementation, the feeding efficiency of the microwave feeding system is adjusted by adjusting the size of the rectangular resonant cavity so that the rectangular resonant cavity can operate in a target state of a low-order mode or a lower-order mode, thereby improving the feeding efficiency of the microwave feeding system.

[0008] In an implementation of the present invention, the distance between the bottom of the rectangular waveguide and the bottom of the rectangular resonant cavity is determined by simulation to improve the feeding efficiency.

[0009] In this implementation, the purpose of further improving the feeding efficiency is achieved by adjusting the distance between the bottom of the rectangular waveguide and the bottom of the rectangular resonant cavity.

[0010] In an implementation of the present invention, the size of the dielectric waveguide is determined by simulation to improve the feeding efficiency.

[0011] In this implementation, by adjusting the size of the dielectric waveguide, the performance of adjusting the microwave coupling to the microwave reaction cavity is achieved, thereby improving the feeding efficiency.

[0012] In one implementation of the present invention, the resonant frequency satisfies the following formula:

[0013]

[0014] Among them, f mnl is the resonant frequency; c is the speed of light in vacuum; ε r and μ r are the relative dielectric constant and relative magnetic permeability of the medium filled in the rectangular resonant cavity; x, y, z are the length, width and height of the rectangular resonant cavity; m, n, l are the number of half wavelengths in the length, width and height of the rectangular resonant cavity.

[0015] In an implementation of the utility model, the microwave feeding system further includes: a microwave source; the microwave source is connected to the waveguide excitation cavity, and the microwave source is used to emit the microwave.

[0016] In an implementation of the utility model, the microwave source includes: a magnetron or a solid-state source; the magnetron or the solid-state source is connected to the waveguide excitation cavity, and the magnetron or the solid-state source is used to emit the microwave.

[0017] In an implementation of the present invention, the mode in which the rectangular waveguide can propagate is the TE10 mode.

[0018] In an implementation of the present invention, the resonance mode of the rectangular resonant cavity includes: a transverse electric field mode or a transverse magnetic field mode.

[0019] In an implementation of the present invention, the shape of the dielectric waveguide includes at least any one of the following: cylindrical, wedge-shaped, rectangular or conical.

[0020] In an implementation of the present invention, the dielectric waveguide is made of a wave-transmitting material; wherein the wave-transmitting material at least includes: quartz and / or corundum or other materials with low microwave absorption.

[0021] As described above, the microwave feeding system described in the utility model has the following beneficial effects:

[0022] (1) Compared with the prior art, the utility model provides a novel microwave feeding system, which uses a combination of rectangular waveguide and rectangular resonant cavity between the microwave reaction cavity and the microwave source to feed by exciting the resonant state of the rectangular resonant cavity, thereby effectively solving the problem of low feeding efficiency caused by directly feeding the microwave source into the microwave reaction cavity in the prior art. The rectangular resonant cavity has the advantages of being easy to process and install, and is convenient for adjusting the feeding efficiency.

[0023] (2) The utility model makes the mode of the rectangular resonant cavity relatively stable by adjusting the size of the rectangular resonant cavity, the distance between the bottom of the rectangular waveguide and the bottom of the rectangular resonant cavity, and the size of the dielectric waveguide. The disturbance caused by the dielectric waveguide is relatively small. When the dielectric properties of the reaction medium in the microwave reaction cavity change greatly, the feeding efficiency can still be maintained at a high level, and the feeding efficiency is not easily affected by the reaction medium in the microwave reaction cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Shown is a principle block diagram of the microwave feeding system described in an embodiment of the utility model.

[0025] Figure 2 Shown is a schematic structural diagram of the microwave feeding system described in an embodiment of the utility model.

[0026] Figure 3 Shown is a schematic diagram of the dimensions of the rectangular resonant cavity described in an embodiment of the present utility model. DETAILED DESCRIPTION

[0027] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0028] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention. The illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0029] See also Figures 1 to 3 The following embodiments of the utility model provide a microwave feeding system. Compared with the prior art, the utility model provides a novel microwave feeding system. By adopting a combination of rectangular waveguide and rectangular resonant cavity between the microwave reaction cavity and the microwave source, feeding is performed by exciting the resonant state of the rectangular resonant cavity, which effectively solves the problem of low feeding efficiency caused by directly feeding the microwave source into the microwave reaction cavity in the prior art. The rectangular resonant cavity has the advantages of easy processing and installation, and is easy to adjust the feeding efficiency. The utility model adjusts the size of the rectangular resonant cavity, the distance between the bottom of the rectangular waveguide and the bottom of the rectangular resonant cavity, and the size of the dielectric waveguide, so that the mode of the rectangular resonant cavity is relatively stable, the disturbance caused by the dielectric waveguide is relatively small, and when the dielectric properties of the reaction medium in the microwave reaction cavity change greatly, the feeding efficiency can still be maintained at a high level, so that the feeding efficiency is not easily affected by the reaction medium in the microwave reaction cavity.

[0030] The technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0031] like Figure 1 and Figure 2 As shown, in one embodiment, the utility model provides a microwave feeding system, which includes: a waveguide excitation cavity 1, a rectangular waveguide 2, a rectangular resonant cavity 3, a dielectric waveguide 4 and a microwave reaction cavity 5.

[0032] Specifically, one end of the rectangular waveguide 2 is connected to the waveguide excitation cavity 1, and the other end of the rectangular waveguide 2 is connected to the rectangular resonant cavity 3, and the bottom of the rectangular waveguide 2 is parallel to the bottom of the rectangular resonant cavity 3; the top of the rectangular resonant cavity 3 is provided with an opening; the dielectric waveguide 4 is arranged in the opening; the microwave reaction cavity 5 is arranged above the rectangular resonant cavity 3; the waveguide excitation cavity 1 is used to convert the mode of the received microwave into a mode that can be propagated by the rectangular waveguide 2 and then feed it into the rectangular waveguide 2, and then feed it into the rectangular resonant cavity 3 through the rectangular waveguide 2, and after mode integration in the rectangular resonant cavity 3, it is fed into the microwave reaction cavity 5 through the dielectric waveguide 4; the difference between the resonant frequency in the rectangular resonant cavity 3 and the frequency of the microwave meets the preset conditions.

[0033] It should be noted that the mode integration of the rectangular resonant cavity 3 refers to the conversion of the transmission mode of the microwaves in the rectangular resonant cavity 3 so as to convert the transmission mode of the microwaves from the original propagation mode in the rectangular waveguide 2 to the resonant mode in the rectangular resonant cavity 3 .

[0034] In one embodiment, the preset condition is that the difference between the resonant frequency in the rectangular resonant cavity 3 and the frequency of the microwave is less than or equal to a preset value.

[0035] It should be noted that the purpose of setting the preset value is to ensure that the resonant frequency in the rectangular resonant cavity 3 is as equal as possible to the frequency of the microwave. Therefore, the preset value is relatively small. However, the specific setting of the preset value is not a condition to limit the present invention. In actual applications, it can be set according to the specific application scenario.

[0036] In one embodiment, the preset condition is that the resonant frequency in the rectangular resonant cavity 3 is equal to the frequency of the microwave.

[0037] That is, corresponding to the above, the default value is 0.

[0038] In one embodiment, the resonant frequency satisfies the following formula:

[0039]

[0040] Among them, f mnl is the resonant frequency; c is the speed of light in vacuum; ε r and μ r are the relative dielectric constant and relative magnetic permeability of the medium filled in the rectangular resonant cavity; x, y, z are the length, width, and height of the rectangular resonant cavity (e.g. Figure 3 m, n, and l are the numbers of half wavelengths in the length, width, and height of the rectangular resonant cavity, respectively.

[0041] It should be noted that m, n, and l can all be any natural number among 0, 1, 2, 3, etc.

[0042] In one embodiment, m, n, and l are all ≤10.

[0043] It should be noted that when m, n, and l are all ≤10, correspondingly, the rectangular resonant cavity 3 operates in the target state.

[0044] In one embodiment, the size of the rectangular resonant cavity 3 is determined by simulation so that the rectangular resonant cavity 3 works in a target state, thereby improving the feeding efficiency of the microwave feeding system.

[0045] Specifically, first, the microwave feeding system is simulated; then, the size of the rectangular resonant cavity 3 is adjusted so that the rectangular resonant cavity 3 works in a target state.

[0046] It should be noted that when the rectangular resonant cavity 3 operates in the target state, it is less affected by the reaction medium in the microwave reaction cavity 5, thereby being able to improve the feeding efficiency of the microwave feeding system.

[0047] In one embodiment, the target state is a low-order mode or a lower-order mode.

[0048] It should be noted that the "lower-order modes" here are relative to the higher-order modes.

[0049] It should be noted that in practical applications, the frequency of microwaves is known, i.e., f mnl Specifically, according to the above-mentioned calculation formula of the resonant frequency, by adjusting the dimensions of the rectangular resonant cavity 3, namely x, y, z, the values ​​of m, n, and l are made smaller (such as all ≤10), so that the rectangular resonant cavity 3 works in the target state.

[0050] In one embodiment, the reflected wave energy reflected from the rectangular resonant cavity 3 to the rectangular waveguide 2 is obtained, and x, y, z are adjusted multiple times according to the reflected wave energy until x, y, z are finally determined.

[0051] It should be noted that the lower the reflected wave energy is, the higher the feeding efficiency is. Therefore, in this embodiment, by adjusting x, y, and z, the reflected wave energy is lowered, and the final x, y, and z are found accordingly.

[0052] In one embodiment, the distance between the bottom of the rectangular waveguide 2 and the bottom of the rectangular resonant cavity 3 is determined by simulation to improve the feeding efficiency.

[0053] Specifically, first, the above microwave feeding system is simulated; then, by adjusting the distance h between the bottom of the rectangular waveguide 2 and the bottom of the rectangular resonant cavity 3 (such as Figure 3 to improve the feeding efficiency.

[0054] In one embodiment, the reflected wave energy reflected from the rectangular resonant cavity 3 to the rectangular waveguide 2 is obtained, so as to adjust the distance h between the bottom of the rectangular waveguide 2 and the bottom of the rectangular resonant cavity 3 according to the reflected wave energy.

[0055] It should be noted that the lower the reflected wave energy is, the higher the feeding efficiency is; therefore, in this embodiment, the reflected wave energy is made lower by adjusting h.

[0056] In one embodiment, h≥0.1λ, wherein λ represents the wavelength of the microwave.

[0057] In one embodiment, the size of the dielectric waveguide 4 is determined by simulation to improve the feeding efficiency.

[0058] Specifically, first, the above microwave feeding system is simulated; then, the feeding efficiency is improved by adjusting the size of the dielectric waveguide 4 .

[0059] In one embodiment, the reflected wave energy reflected from the rectangular resonant cavity 3 to the rectangular waveguide 2 is obtained, so that the size of the dielectric waveguide 4 is adjusted according to the reflected wave energy.

[0060] It should be noted that the lower the reflected wave energy is, the higher the feeding efficiency is; therefore, in this embodiment, the reflected wave energy is made lower by adjusting the size of the dielectric waveguide 4 .

[0061] In one embodiment, the shape of the dielectric waveguide 4 at least includes but is not limited to any one of the following: cylindrical, wedge-shaped, rectangular or conical.

[0062] by Figure 3 In the figure, the shape of the dielectric waveguide 4 is a cylinder + a cone as an example; specifically, adjusting the size of the dielectric waveguide 4 is to adjust the height t of the cone (this part extends into the rectangular resonant cavity 3), the diameter d and the height s of the cylinder.

[0063] It should be noted that by adjusting the size of the dielectric waveguide 4 , the performance of microwave coupling from the rectangular resonant cavity 3 to the microwave reaction cavity 5 can be adjusted; specifically, the higher the feeding efficiency, the better the performance of microwave coupling from the rectangular resonant cavity 3 to the microwave reaction cavity 5 .

[0064] It should be noted that, through the above adjustment method, the mode of the rectangular resonant cavity 3 is relatively stable, and the disturbance caused by the dielectric waveguide is relatively small, so that the feeding efficiency is not easily affected by the reaction medium in the microwave reaction cavity 5.

[0065] In one embodiment, after h and / or the size of the dielectric waveguide 4 are adjusted, the size of the rectangular resonant cavity 3 is adjusted again.

[0066] Specifically, after multiple simulation calculations, the size, h, of the rectangular resonant cavity 3 and the size of the dielectric waveguide 4 are finally determined, so as to finally build the microwave feeding system.

[0067] In one embodiment, the microwave feeding system further includes: a microwave source 6 .

[0068] Specifically, the microwave source 6 is connected to the waveguide excitation cavity 1 , and the microwave source 6 is used to emit the microwave.

[0069] In one embodiment, the microwave source 6 includes a magnetron or a solid-state source.

[0070] Specifically, the magnetron or the solid-state source is connected to the waveguide excitation cavity 1 , and the magnetron or the solid-state source is used to emit the microwave.

[0071] In one embodiment, the rectangular waveguide 2 can propagate in a TE10 mode.

[0072] In one embodiment, the resonance mode of the rectangular resonant cavity 3 includes: a transverse electric field mode or a transverse magnetic field mode.

[0073] In one embodiment, the dielectric waveguide 4 is made of a wave-transmitting material; wherein the wave-transmitting material at least includes: quartz and / or corundum.

[0074] In one embodiment, the rectangular resonant cavity 3 is made of metal material.

[0075] In one embodiment, the opening is located at the center of the top of the rectangular resonant cavity 3 .

[0076] It should be noted that the existing microwave reactor feeding method generally adopts the following two methods: (1) connecting the magnetron antenna to a rectangular waveguide, and then feeding the rectangular waveguide into the microwave reaction cavity; (2) connecting the magnetron antenna to a rectangular waveguide, feeding it into a circular resonant cavity through the rectangular waveguide, and then feeding it into the microwave reactor through the circular resonant cavity.

[0077] The existing feeding method (1) also has the following problems: it is easily affected by the materials in the microwave reaction cavity, resulting in low feeding efficiency; the existing feeding method (2) has the following problems: the use of circular resonant cavity feeding has the disadvantages of complex processing and difficulty in adjusting efficiency.

[0078] The microwave feeding system provided by the utility model adopts a rectangular waveguide and a rectangular resonant cavity to perform feeding between a microwave reaction cavity and a microwave source, which effectively solves the problem of low feeding efficiency caused by directly feeding a microwave source into a microwave reaction cavity in the prior art. The rectangular resonant cavity has the advantages of being easy to process and install, and is convenient for adjusting the feeding efficiency. The utility model can make the rectangular resonant cavity in a relatively stable mode by adjusting the size of the rectangular resonant cavity, the distance between the rectangular waveguide and the bottom of the rectangular resonant cavity, and the size of the dielectric waveguide, so that when the dielectric properties of the reaction medium in the microwave reaction cavity change greatly, a high feeding efficiency can still be maintained.

[0079] The descriptions of the processes or structures corresponding to the above-mentioned figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0080] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

Claims

1. A microwave feeding system, characterized in that: The microwave feeding system comprises: a waveguide excitation cavity, a rectangular waveguide, a rectangular resonant cavity, a dielectric waveguide and a microwave reaction cavity; One end of the rectangular waveguide is connected to the waveguide excitation cavity, the other end of the rectangular waveguide is connected to the rectangular resonant cavity, and the bottom of the rectangular waveguide is parallel to the bottom of the rectangular resonant cavity; The top of the rectangular resonant cavity is provided with an opening; the dielectric waveguide is arranged in the opening; The microwave reaction cavity is arranged above the rectangular resonant cavity; The waveguide excitation cavity is used to convert the mode of the received microwave into a mode that can be propagated by the rectangular waveguide, and then feed it into the rectangular waveguide, and then feed it into the rectangular resonant cavity through the rectangular waveguide, and after mode integration in the rectangular resonant cavity, it is fed into the microwave reaction cavity through the dielectric waveguide; the difference between the resonant frequency in the rectangular resonant cavity and the frequency of the microwave meets the preset conditions.

2. The microwave feeding system according to claim 1, characterized in that: The resonant frequency satisfies the following formula: Among them, f mnl is the resonant frequency; c is the speed of light in vacuum; ε r and μ r are the relative dielectric constant and relative magnetic permeability of the medium filled in the rectangular resonant cavity; x, y, z are the length, width and height of the rectangular resonant cavity; m, n, l are the number of half wavelengths in the length, width and height of the rectangular resonant cavity.

3. The microwave feeding system according to claim 1, characterized in that: The microwave feeding system further includes: a microwave source; the microwave source is connected to the waveguide excitation cavity, and the microwave source is used to emit the microwave.

4. The microwave feeding system according to claim 3, characterized in that: The microwave source includes: a magnetron or a solid-state source; the magnetron or the solid-state source is connected to the waveguide excitation cavity, and the magnetron or the solid-state source is used to emit the microwave.

5. The microwave feeding system according to claim 1, characterized in that: The rectangular waveguide can propagate in the TE10 mode.

6. The microwave feeding system according to claim 1, characterized in that: The resonance mode of the rectangular resonant cavity includes: a transverse electric field mode or a transverse magnetic field mode.

7. The microwave feeding system according to claim 1, characterized in that: The shape of the dielectric waveguide includes at least any one of the following: cylindrical, wedge-shaped, rectangular or conical.

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