CN110191530B - Microwave radiation heating device - Google Patents
Microwave radiation heating device Download PDFInfo
- Publication number
- CN110191530B CN110191530B CN201910451301.9A CN201910451301A CN110191530B CN 110191530 B CN110191530 B CN 110191530B CN 201910451301 A CN201910451301 A CN 201910451301A CN 110191530 B CN110191530 B CN 110191530B
- Authority
- CN
- China
- Prior art keywords
- heating device
- medium
- outer conductor
- antenna
- heating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/64—Heating using microwaves
- H05B6/72—Radiators or antennas
Abstract
The invention discloses a microwave radiation heating device, and relates to the technical field of microwave energy application devices. The heating device is provided with a metal box body with a heating cavity and a plurality of spiral microwave radiation antenna assemblies which are uniformly and parallelly arranged in the heating cavity; the antenna assembly comprises a medium outer cylinder for preventing a heated medium from entering the inside of the antenna assembly, and the antenna assembly is placed in the heated medium through the medium outer cylinder and uniformly radiates electromagnetic waves to the heated medium along the radial direction of the antenna assembly when in operation, and the heating device can uniformly heat the medium.
Description
Technical Field
The invention relates to the technical field of microwave energy application devices. And more particularly to a microwave radiation heating apparatus.
Background
In the prior art, the microwave feeding means used in the microwave energy application field is mostly radiated by one or more waveguide ports 10. For example, solid materials such as food 20 or materials are placed in a resonant cavity or waveguide, and the heating effect of the microwave is utilized to process the objects, and the specific structure is shown in fig. 1. Uneven heating of the medium can be caused by uneven distribution of the microwave field inside the cavity.
In general, in order to overcome the problem of uneven distribution of the microwave field, a mode stirrer, a rotating medium and the like can be added inside the microwave cavity to move the medium relative to the microwave electromagnetic field. When the microwaves are transmitted in a lossy medium,
and
by a factor e-αzThe greater the attenuation, the greater the loss of the medium, the smaller the microwave penetration distance. To overcome the limitation of limited distance penetration of microwaves and improve the uniformity of heating, it is common to reduce the volume of the microwave-affected object.
In order to meet the requirement of microwave energy engineering application, the currently used microwave with the frequency of 915MHz or 2450MHz can not penetrate 1m3Or a larger volume of medium, conventional waveguide port feeding has not been able to meet the requirements. However, the addition of the electric stirring device can significantly reduce the reliability and service life of the equipment and increase the running cost of the equipment.
In order to improve the uniformity of microwave heating, improve the reliability of microwave equipment and reduce the use cost of microwave equipment, innovative changes need to be made on the basis of the original structure.
Disclosure of Invention
The invention aims to provide a microwave radiation heating device capable of uniformly heating a medium.
In order to achieve the purpose, the invention adopts the following technical scheme:
a microwave radiant heating apparatus comprising: the microwave radiation heating device comprises a metal box body with a heating cavity, and a plurality of spiral microwave radiation antenna assemblies which are uniformly and parallelly arranged in the heating cavity;
the antenna assembly comprises a medium outer cylinder for preventing a heated medium from entering the inside of the antenna assembly, and the antenna assembly is placed in the heated medium through the medium outer cylinder and uniformly radiates electromagnetic waves to the heated medium along the radial direction of the antenna assembly when in operation.
Furthermore, it is preferred that the heating means comprises five helical microwave radiation antenna assemblies located within the heating chamber;
one antenna assembly is placed in the center of the heating cavity, and the other four antenna assemblies are centered on the antenna assembly in the center and form a square.
In addition, it is preferable that the distance between the antenna component at the center position and the four antenna components at the periphery is 50 to 100 mm.
Further, it is preferable that the antenna assembly includes: the device comprises a cylindrical outer conductor with an opening at one end and an inner conductor which is positioned in the outer conductor and is supported and fixed with the outer conductor through a support; the medium outer cylinder is sleeved on the outer surface of the outer conductor;
along the axial direction of outer conductor, outer conductor includes the spiral groove that runs through its lateral wall inside and outside surface, the spiral groove includes at least one pitch transition, the electromagnetic wave is evenly outwards radiated to the pitch transition of spiral groove of antenna module accessible.
In addition, the preferable scheme is that the material of the medium outer cylinder is polytetrafluoroethylene or polyether ether ketone; the thickness of the medium outer cylinder is 2-6 mm.
In addition, preferably, the pitch of the pitch transition section of the thread groove gradually increases from the end close to the outer conductor opening to the end far away from the outer conductor opening.
In addition, preferably, the pitch gradual change mode of the pitch gradual change section of the screw groove is linear gradual change.
In addition, preferably, the spiral groove on the side wall of the outer conductor is formed by winding or metal cutting.
Preferably, the inner conductor and the outer conductor are coaxially disposed.
In addition, it is preferable that the material of the supporter is polytetrafluoroethylene or polyetheretherketone.
The invention has the following beneficial effects:
the microwave radiation heating device provided by the invention can directly insert the antenna component into the heated medium, increases the action area of the antenna and the medium, effectively improves the temperature uniformity of the heated medium along the axial direction (Z direction in the figure) and the radial direction (R direction in the figure) of the antenna component in the aspect of heating the large-volume medium by the microwave for engineering, and has the advantages of simple structure assembly, convenient operation, strong controllability and high reliability. Compared with the traditional microwave heating device, the heating device can greatly improve the reliability of the equipment, prolong the service life of the equipment, reduce the use energy consumption of the equipment and reduce the operation cost of the equipment in the aspect of heating large-volume media by microwaves for engineering.
Drawings
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
Fig. 1 shows a schematic view of a structure of a microwave heating object which is common in the prior art.
Figure 2 shows a schematic diagram of the construction of a helical microwave radiating antenna assembly in a heating device according to the invention.
Fig. 3 shows a schematic view of a partial structure of the microwave radiation heating apparatus of the present invention.
Fig. 4 shows the distribution pattern of the electric field in the axial direction of the antenna assembly in the antenna assembly of the present invention, which is obtained by simulation using the CST2010 software.
Description of reference numerals: 10. a waveguide port; 20. a food; 1. an antenna assembly; 11. an outer conductor; 111. a screw groove; 12. an inner conductor; 13. a supporter; 14. a medium outer cylinder; 2. a metal box body; 3. a microwave feed port.
Detailed Description
In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.
In the description of the present invention, it should be noted that the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present invention. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
In the prior art, most of the microwave feeding modes used in the microwave energy application field are one or more waveguide ports 10 for radiation, for example, solid substances such as food 20 or materials are placed inside a resonant cavity or a waveguide, and the object is processed by using the heating effect of microwaves, and the specific structure is shown in fig. 1, and the inside of the cavity can cause uneven heating of a medium due to uneven distribution of a microwave field. The invention provides a microwave radiation heating device, aiming at the problems that in the traditional microwave heating structure in the prior art, microwaves cannot penetrate into a medium deeply, so that the temperature inside and on the surface of the medium is obviously uneven, and the traditional microwave heating device cannot adapt to the problem that the requirement on the temperature uniformity of the whole medium is high (the temperature difference cannot exceed +/-5 ℃). Specifically, the following detailed description is made with reference to the accompanying drawings.
Fig. 1 shows a schematic view of a structure of a microwave heating object which is common in the prior art. Figure 2 shows a schematic diagram of the construction of a helical microwave radiating antenna assembly in a heating device according to the invention. Fig. 3 shows a schematic view of a partial structure of the microwave radiation heating apparatus of the present invention. Fig. 4 shows the electric field distribution in the axial direction of the antenna assembly in the heating device of the present invention, which was simulated by the CST2010 software.
The microwave radiation heating apparatus includes: the microwave radiation heating device comprises a metal box body 2 with a heating cavity, and a plurality of spiral microwave radiation antenna assemblies 1 which are uniformly and parallelly arranged and are positioned in the heating cavity; the antenna component 1 comprises a medium outer cylinder 14 for preventing a heated medium from entering the inside of the antenna component 1, and the antenna component 1 is placed in the heated medium through the medium outer cylinder 14 and uniformly radiates electromagnetic waves to the heated medium along the radial direction of the antenna component 1 during operation.
In the heating device, the traditional microwave feeding mode with one or more waveguide ports is changed into a plurality of antenna radiation type heating modes which directly act on the inside of a heated medium, a microwave field is radiated to the inside of a heating cavity by an antenna component 1 and absorbed by the heated medium, so that the heating is more uniform; the medium outer cylinder 14 mainly prevents the heated medium from entering the inside of the antenna component 1, can bear certain pressure and temperature, and is acid-resistant and alkali-resistant. By adopting the structure, the microwave radiation heating device effectively improves the temperature uniformity of the heated medium along the axial direction (Z direction in the figure) and the radial direction (R direction in the figure) of the antenna component 1, and meanwhile, the structure has the advantages of simple assembly, convenient operation, strong controllability and high reliability.
To further improve the uniformity of R-direction microwave heating, the heating apparatus comprises five helical microwave radiation antenna assemblies 1 located within a heating chamber; one of the antenna assemblies 1 is placed in the center of the heating cavity, and the other four antenna assemblies 1 are centered on the antenna assembly 1 in the center and form a square, as shown in fig. 3.
In an embodiment of the present invention, it is preferable that the distance between the antenna component 1 in the central position and the four antenna components 1 in the periphery is 50-100 mm. The reason is that the microwave depth into the medium is limited, the microwave field intensity is inversely proportional to the distance, if the distance d between the radiation antennas is too large, the field intensity between the radiation antennas is too small, which can cause the uneven heating of the medium; meanwhile, if the distance between the radiation antennas is too small, mutual crosstalk between the radiated electromagnetic waves can be caused, the heating efficiency is reduced, and the service life of the microwave feed source can be even affected in severe cases. Through computer simulation optimization, the distance d (50-100mm) between the central radiation antenna and the surrounding antennas of the device is designed, so that the nonuniformity of microwave heating in the R direction can be improved, and the influence among the antennas is reduced to the minimum.
As shown in fig. 2, preferably, the antenna assembly 1 of the present invention includes: a cylindrical outer conductor 11 with one open end, and an inner conductor 12 which is positioned in the outer conductor 11 and is supported and fixed with the outer conductor 11 through a support 13; the medium outer cylinder 14 is sleeved on the outer surface of the outer conductor 11; in the axial direction of the outer conductor 11, the outer conductor 11 includes a spiral groove 111 penetrating through the inner and outer side surfaces of the side wall thereof, the spiral groove 111 includes at least one pitch transition, and the antenna assembly 1 can radiate electromagnetic waves uniformly outwards through the pitch transition of the spiral groove 111. It will be understood by those skilled in the art that the thread groove 111 may be provided as a pitch transition in its entirety or as a portion thereof. When a part of the thread groove 111 is provided with a gradual pitch transition section, the thread groove 111 is provided with a uniform pitch section at other places. In the above cases, the antenna assembly 1 can radiate electromagnetic waves uniformly outward through the pitch transition of the spiral groove 111. In order to make the antenna assembly 1 radiate electromagnetic waves uniformly outwards through the spiral groove 111, it can be understood by those skilled in the art that the pitch of the pitch transition section of the spiral groove 111 gradually increases from the end close to the opening of the outer conductor 11 to the end far from the opening of the outer conductor 11, and the efficiency of radiating electromagnetic waves from the end of the outer conductor 11 far from the opening of the outer conductor 11 is higher than that of radiating electromagnetic waves from the end of the outer conductor 11 close to the opening of the outer conductor 11 through the pitch transition, so as to offset the loss of electromagnetic waves when propagating in the inner conductor 12, and further ensure the uniformity of electromagnetic waves radiated outwards by the antenna assembly 1 in the axial direction thereof, and thus the temperature nonuniformity of the microwave heating medium along the axial direction of the antenna assembly 1 can be remarkably improved.
Further preferably, the pitch gradual change manner of the pitch gradual change section of the thread groove 111 is a linear gradual change manner, and the gradual change manner is an optimal manner obtained through a plurality of experimental verifications. In the actual design process, the pitch of the thread groove 111 near the open end of the outer conductor 11 is gradually changed to the pitch of the thread groove 111 far from the open end of the outer conductor 11 in a linear gradual change manner.
In the invention, the medium outer cylinder 14 can not only be penetrated by electromagnetic waves, but also can be used for preventing the heated medium from entering the inside of the antenna component 1, and meanwhile, the medium outer cylinder 14 must have a certain thickness, preferably, the thickness of the medium outer cylinder 14 is 2-6 mm; the medium outer cylinder 14 needs to withstand pressure (within 10 atmospheres), temperature (200 ℃), strong acid and strong alkali for a long time, and the material is preferably polytetrafluoroethylene or polyetheretherketone.
In the preferred embodiment of the present invention, the spiral groove 111 on the side wall of the outer conductor 11 is formed by winding or metal cutting, and those skilled in the art can select other suitable forming manners according to actual needs, which is not limited further in the present invention.
Preferably, the inner conductor 12 and the outer conductor 11 are coaxially arranged, and the coaxial arrangement is supported and maintained by a supporter 13, so as to ensure the electromagnetic wave transmission function of the antenna assembly 1. Further, the material of the supporter 13 is polytetrafluoroethylene or polyetheretherketone.
The CST2010 software is utilized to simulate the distribution diagram of the electric field in the Z direction of the microwave transmission direction in the structure of the antenna component 1 of the invention, and the relation curve shown in the attached figure 4 is obtained. It can be seen from the figure that there is only a 20% difference between the maxima in the electric field strength over the entire microwave transmission direction.
According to the structure of the microwave radiation heating device provided by the invention, 5 assembled radiation antenna components 1 are inserted into a 10L microwave resonant cavity in a mode shown in the attached figure 3, 5 2450MHz magnetrons with the output power of 800W are connected at a microwave feed inlet 3, a heating object is deionized water, the heating time is automatically controlled for 30 minutes, the water temperature is heated from the normal temperature of 22 ℃ to 170 ℃, and the heat is preserved for 24 hours. Several temperature sensors are placed at different positions in the heating cavity, the change of water temperature in the heating and heat preservation processes is monitored, and the test result shows that the maximum temperature difference in the radial direction is 10 ℃ and the maximum temperature difference in the axial direction is 5 ℃. The tested temperature uniformity is obviously superior to the traditional microwave heating mode.
It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations or modifications may be made on the basis of the above description, and all embodiments may not be exhaustive, and all obvious variations or modifications may be included within the scope of the present invention.
Claims (9)
1. A microwave radiant heating apparatus, comprising: the microwave radiation heating device comprises a metal box body with a heating cavity, and a plurality of spiral microwave radiation antenna assemblies which are uniformly and parallelly arranged in the heating cavity;
the antenna assembly comprises a medium outer cylinder for preventing a heated medium from entering the inside of the antenna assembly, and the antenna assembly is placed in the heated medium through the medium outer cylinder and uniformly radiates electromagnetic waves to the heated medium along the radial direction of the antenna assembly in operation;
the antenna assembly includes: the device comprises a cylindrical outer conductor with an opening at one end and an inner conductor which is positioned in the outer conductor and is supported and fixed with the outer conductor through a support; the medium outer cylinder is sleeved on the outer surface of the outer conductor;
along the axial direction of outer conductor, outer conductor includes the spiral groove that runs through its lateral wall inside and outside surface, the spiral groove includes at least one pitch transition, the electromagnetic wave is evenly outwards radiated to the pitch transition of spiral groove of antenna module accessible.
2. A heating device as claimed in claim 1, wherein the heating device comprises five helical microwave radiation antenna assemblies located within a heating chamber;
one antenna assembly is placed in the center of the heating cavity, and the other four antenna assemblies are centered on the antenna assembly in the center and form a square.
3. A heating device according to claim 2, characterized in that the distance between the centrally located antenna component and the four surrounding antenna components is 50-100 mm.
4. The heating device of claim 1, wherein the material of the medium outer cylinder is polytetrafluoroethylene or polyetheretherketone; the thickness of the medium outer cylinder is 2-6 mm.
5. The heating device of claim 1, wherein the pitch of the gradual pitch transition of the thread groove increases from an end proximate to the outer conductor opening to an end distal from the outer conductor opening.
6. The heating device of claim 5, wherein the pitch progression of the flights is linear.
7. The heating device of claim 1, wherein the spiral groove on the side wall of the outer conductor is formed by winding or metal cutting.
8. The heating device of claim 1, wherein the inner conductor is coaxially disposed with the outer conductor.
9. The heating device of claim 1, wherein the material of the support is polytetrafluoroethylene or polyetheretherketone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910451301.9A CN110191530B (en) | 2019-05-28 | 2019-05-28 | Microwave radiation heating device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910451301.9A CN110191530B (en) | 2019-05-28 | 2019-05-28 | Microwave radiation heating device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110191530A CN110191530A (en) | 2019-08-30 |
| CN110191530B true CN110191530B (en) | 2021-10-29 |
Family
ID=67718324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910451301.9A Active CN110191530B (en) | 2019-05-28 | 2019-05-28 | Microwave radiation heating device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110191530B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04264387A (en) * | 1990-10-26 | 1992-09-21 | Bosch Siemens Hausgeraete Gmbh | Home microwave apparatus |
| WO1998016087A1 (en) * | 1996-10-08 | 1998-04-16 | Cadif S.R.L. | Electric radiating tube, generator and diffuser of heat, of insulating and of highly conducting spiralled bands |
| CN103841913A (en) * | 2011-04-08 | 2014-06-04 | 柯惠有限合伙公司 | Flexible microwave catheters for natural or artificial lumens |
| CN105813252A (en) * | 2016-04-28 | 2016-07-27 | 电子科技大学 | Industrial microwave heating device adopting radial radiation power of helical antennas |
| CN107087323A (en) * | 2017-05-22 | 2017-08-22 | 吴凡 | Microwave heats heat conductive rod |
-
2019
- 2019-05-28 CN CN201910451301.9A patent/CN110191530B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04264387A (en) * | 1990-10-26 | 1992-09-21 | Bosch Siemens Hausgeraete Gmbh | Home microwave apparatus |
| WO1998016087A1 (en) * | 1996-10-08 | 1998-04-16 | Cadif S.R.L. | Electric radiating tube, generator and diffuser of heat, of insulating and of highly conducting spiralled bands |
| CN103841913A (en) * | 2011-04-08 | 2014-06-04 | 柯惠有限合伙公司 | Flexible microwave catheters for natural or artificial lumens |
| CN105496552A (en) * | 2011-04-08 | 2016-04-20 | 柯惠有限合伙公司 | Flexible microwave catheters |
| CN105813252A (en) * | 2016-04-28 | 2016-07-27 | 电子科技大学 | Industrial microwave heating device adopting radial radiation power of helical antennas |
| CN107087323A (en) * | 2017-05-22 | 2017-08-22 | 吴凡 | Microwave heats heat conductive rod |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110191530A (en) | 2019-08-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2417831B1 (en) | Microwave processing chamber | |
| KR100368943B1 (en) | microwave | |
| US8383999B2 (en) | Device for heating a sample by microwave radiation | |
| AU3105699A (en) | Apparatus for supplying microwave energy to a cavity | |
| CN106231712B (en) | Antenna assembly of microwave oven and microwave oven | |
| US4185181A (en) | Microwave oven | |
| US11045249B2 (en) | Electrode for a system for heating biological tissue via RF energy | |
| CN109413789A (en) | A kind of control method of micro-wave oven and micro-wave oven | |
| CN107087323A (en) | Microwave heats heat conductive rod | |
| KR101558443B1 (en) | Device for applying electromagnetic energy to a reactive medium | |
| CN110191530B (en) | Microwave radiation heating device | |
| WO2020249082A1 (en) | Electric adjusting antenna structure for changing microwave electric field distribution | |
| CN110113833A (en) | A kind of microwave radiation heating antenna component | |
| CN210958867U (en) | Electrically tunable antenna structure for changing microwave electric field distribution | |
| JP3730854B2 (en) | High frequency heating device | |
| CN108682961B (en) | Circular waveguide leaky wave slot antenna based on TM01 mode | |
| CN114173442A (en) | Waveguide slot array heater designed by Taylor function synthesis method | |
| CN109417838B (en) | Microwave feeding system | |
| CN111991701B (en) | Four-quadrant loading 433MHz circular waveguide radiator | |
| CN211988573U (en) | Large-capacity microwave chemical reaction device | |
| GB2615765A (en) | Dual-frequency microwave antenna | |
| RU2085057C1 (en) | Superhigh-frequency oven | |
| KR100305962B1 (en) | Microwave waveguide system | |
| RU2203597C1 (en) | Vacuum sublimation drying apparatus | |
| KR100302915B1 (en) | Waveguide of microwave oven |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |