An electrostatic atomization micro burner based on a highly integrated micropore array

Abstract

The invention discloses an electrostatic atomization micro burner based on a highly integrated micrometer hole array, comprising a combustion catalytic chamber, wherein the top and bottom of the combustion catalytic chamber are respectively a combustion outlet pipe and a fuel inlet pipe, and the fuel inlet pipe is respectively connected to a feed pipe and an air inlet pipe; a micrometer hole array electrostatic atomization unit and a collection catalytic unit are sequentially installed at the feed inlet of the feed pipe from the outside to the inside; the micrometer hole array electrostatic atomization unit comprises an electrostatic spray chamber, one side of the electrostatic spray chamber is connected to a fuel chamber through a pipeline, and the other side of the electrostatic spray chamber is sequentially installed from the inside of the electrostatic spray chamber to the outside with a micrometer hole array plate and an adjustment plate; the micrometer hole array plate and the adjustment plate are connected to the negative electrode of a negative high-voltage power supply to form a first-order potential difference; the collection catalytic unit is a collection grid, the collection grid is grounded, and a second-order potential difference exists between the adjustment plate and the collection grid; the invention can greatly increase the atomization flow rate on the basis of generating submicron-level atomized droplets with excellent monodispersity.

Description

Technical Field

[0001] The invention belongs to the field of micro combustion, and in particular relates to an electrostatic atomization micro burner based on a highly integrated micrometer hole array. Background Art

[0002] As one of the main types of micro-power devices, micro-burners have very obvious advantages. The energy density of fuel can reach dozens of times that of traditional chemical batteries. The continuous combustion of fuel can provide stable energy for the system for a long time, and there will be no energy loss as the shelf time increases. At the same time, the use of efficient clean energy as fuel can effectively reduce environmental pollution and avoid the problem of difficult collection and treatment of batteries after they are discarded. This makes micro-burners have broad application potential in high-tech fields such as automotive electronics, aerospace, automatic control, and national defense. In micro-power devices, people often use gas or liquid hydrocarbon fuels as power sources and use micro-burners as combustion devices. However, although micro-burners have various advantages, as their structural dimensions are reduced, they also face some technical problems that need to be solved urgently. The micro-burners currently available on the market are mainly based on easily combustible gas fuels. Although these micro-burners have a certain atomization combustion effect, the micro-structure design is complex and the processing is difficult. At the same time, compared with liquid fuels, the calorific value generated by gas micro-burners is significantly smaller. However, the atomization flow rate of the current liquid micro burners is low, the fuel stays in the burner for a short time, the fuel liquid is difficult to atomize or the size of the atomized droplets is too large, the combustion is unstable, and the combustion effect is unsatisfactory. Summary of the invention

[0003] In order to solve the shortcomings of the prior art, the present invention proposes an electrostatic atomization micro burner based on a highly integrated micropore array. The burner adopts a highly integrated micropore electrostatic micro-spray module with a mechanical supercharger, which can greatly increase the atomization flow rate on the basis of producing submicron-level atomized droplets with excellent monodispersity, and realize a liquid micro combustion with high energy, high combustion rate and low pollution emission.

[0004] The technical solution adopted by the present invention is as follows:

[0005] An electrostatic atomization micro burner based on a highly integrated micropore array comprises a combustion catalytic chamber, the top and bottom of the combustion catalytic chamber are respectively a combustion outlet pipe and a fuel inlet pipe, the fuel inlet pipe is respectively connected to a feed pipe and an air inlet pipe; a micropore array electrostatic atomization unit and a collection catalytic unit are sequentially installed at the feed inlet of the feed pipe from the outside to the inside; the micropore array electrostatic atomization unit comprises an electrostatic spray chamber, one side of the electrostatic spray chamber is connected to a fuel chamber through a pipeline, and the other side of the electrostatic spray chamber is sequentially installed with a micropore array plate and an adjustment plate from the inside of the electrostatic spray chamber to the outside; the micropore array plate and the adjustment plate are connected to the negative electrode of a negative high-voltage power supply to form a first-order potential difference; the collection catalytic unit is a collection grid, the collection grid is grounded, and a second-order potential difference exists between the adjustment plate and the collection grid.

[0006] Furthermore, there are two feed pipes; the two feed pipes are arranged perpendicular to the fuel inlet pipe, and the outlets of the two feed pipes are arranged opposite to each other; the air inlet pipe is arranged vertically and the air outlet end of the air inlet pipe is arranged opposite to the fuel inlet pipe 18; an axial flow fan is installed in the fuel inlet pipe.

[0007] Furthermore, the micrometer hole array plate adopts a silicon substrate and a super hydrophobic coating is coated on the surface of the micrometer hole array plate; micrometer circular holes A are arranged in an array on the micrometer hole array plate.

[0008] Furthermore, an annular groove is formed around the micrometer circular hole A.

[0009] Furthermore, the adjustment plate is a silicon substrate with a thickness of 150 microns and conductive coatings are sprayed on the upper and lower surfaces. Meanwhile, micron circular holes B are opened on the adjustment plate; micron circular holes B and micron circular holes A are arranged one by one.

[0010] Furthermore, the diameter ratio of the micron pore A to the micron pore B is 1:1.4, the diameter of the micron pore A is 100-150 microns, and the diameter of the micron pore B is 140-210 microns.

[0011] Furthermore, the voltage range of the negative high voltage power supply connected to the micrometer hole array plate can be 1-30KV, the voltage range of the negative high voltage power supply connected to the adjustment plate can be 0-20KV, and the voltage of the adjustment plate is less than the voltage of the micrometer hole array plate.

[0012] Furthermore, the collecting grid is provided with an array of square holes with a side length of 70 microns. The collecting grid is used to gather the atomized fuel using a high voltage electric field to form a large number of charged micro droplets with excellent monodispersity.

[0013] Furthermore, a combustion grid is installed inside the combustion catalytic chamber. The combustion grid is provided with regular hexagonal holes arranged in an array. The side length of the regular hexagonal holes is 40 microns. The surface of the combustion grid is sprayed with a combustion catalyst.

[0014] Beneficial effects of the present invention:

[0015] 1. The present invention is an electrostatic atomization micro burner with a highly integrated micropore array. The principle of electrostatic atomization is used to combine a micropore array plate, an adjustment electrode plate and a droplet collection grid to form an atomization jet device. The structure is simple and the step of installing a protruding capillary required for traditional electrostatic atomization is omitted. The circular holes on the micropore array plate, the adjustment electrode plate and the collection grid are used to complete the atomization process of the liquid. The intensity of the atomization can be controlled by adjusting parameters such as voltage. At the same time, the concentric circular grooves outside the circular holes of the micropore array plate can prevent the mutual fusion of liquid cones during the atomization process and interfere with the jet. In addition, the combustion grid is separately arranged in a combustion catalytic chamber with a variable diameter, so that the liquid fuel is charged and atomized, evaporated and gasified, and burned in steps to achieve complete combustion of the liquid fuel. Since the combustion catalytic chamber is an inlet with a gradually increasing diameter, the speed of the atomized fuel entering the combustion catalytic chamber will be reduced, and the eddy current disturbance generated at the same time greatly increases the contact time between the mixed gas and the combustion grid, thereby enhancing the catalytic effect.

[0016] 2. The voltage controller, booster pump and gas flow valve form a control module to deliver liquid fuel from the fuel chamber through the electrostatic spray cavity to the micrometer hole array electrostatic atomization module. The internal pressure of the fuel chamber can be adjusted by the voltage controller and the gas flow valve to obtain a suitable atomization amount. The air enters from the intake pipe, and its flow is controlled by the axial flow fan by adjusting the number of revolutions, thereby ensuring a suitable mixture of air and liquid fuel and improving combustion efficiency.

[0017] 3. The micrometer hole array plate and the adjustment plate of the present invention adopt micro-nano processing technology, and are provided with circular holes distributed in a regular hexagon, which can be 7, 19, or 64. At the same time, two highly integrated electrostatic atomization modules are designed to be symmetrically distributed in one burner, which greatly improves the flow rate of liquid fuel atomization. The mesh of the combustion grid is designed to be a regular hexagon, and the mesh is correspondingly reduced, which not only allows the gas to be discharged smoothly, but also prolongs the residence time of the gas on the combustion grid, making the combustion more complete. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the electrostatic atomization micro burner of the present invention;

[0019] Figure 2 A schematic diagram of a micrometer array electrostatic spray module of an electrostatic atomization micro burner of the present invention;

[0020] Figure 3 A bottom view of the micrometer array plate of the present invention;

[0021] Figure 4 It is a partial enlarged view of the annular groove of the micrometer array plate of the present invention;

[0022] Figure 5A bottom view of the adjustment plate of the present invention;

[0023] Figure 6 It is a schematic diagram of the structure of the droplet collection grid;

[0024] Figure 7 It is a structural schematic diagram of the combustion grid;

[0025] In the figure, 1. voltage controller, 2. boost pump, 3. gas flow valve, 4. electrostatic spray chamber, 5. micrometer hole array plate, 6. adjustment plate, 7. collection grid, 8. axial flow fan, 9. combustion grid, 10. ignition needle, 11. fuel chamber, 12. feed pipe, 13. combustion catalytic chamber, 14. combustion outlet pipe, 15. intake pipe, 16. fuel spray, 17. annular groove, 18. fuel inlet pipe. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] like Figure 1 An electrostatic atomization micro burner based on a highly integrated micropore array is shown, comprising a combustion catalytic chamber 13, the top of the combustion catalytic chamber 13 is a combustion outlet pipe 14, and an ignition needle 10 is installed in the combustion outlet pipe 14; the bottom of the combustion catalytic chamber 13 is a fuel inlet pipe 18, and the air inlet end of the fuel inlet pipe 18 is respectively connected to the feed pipe 12 and the air inlet pipe 15, and the fuel inlet pipe 18, the feed pipe 12 and the air inlet pipe 15 are interconnected; in this embodiment, there are two feed pipes 12; the two feed pipes 12 are arranged perpendicular to the fuel inlet pipe 18, and the outlet ports of the two feed pipes 12 are arranged opposite to each other; the air inlet pipe 15 is arranged vertically and the air outlet end of the air inlet pipe 15 is arranged opposite to the fuel inlet pipe 18; an axial flow fan 8 is installed in the fuel inlet pipe 18, and the axial flow fan 8 is used to input air into the combustion catalytic chamber 13.

[0028] The micrometer hole array electrostatic atomization unit and the collection catalytic unit are sequentially installed at the inlet of the two feed pipes 12 from the outside to the inside, and the micrometer hole array electrostatic atomization unit is arranged toward the fuel inlet pipe 18. Figure 2The micropore array electrostatic atomization unit includes an electrostatic spray chamber 4. One side of the electrostatic spray chamber 4 is connected to a fuel chamber 11 through a pipeline. The fuel chamber 11 is connected to the outlet of the booster pump 2. The booster pump 2 is connected to a voltage controller 1. The start and stop of the booster pump 2 is controlled by the voltage controller 1. The booster pump 2 is also equipped with a gas flow valve 3. The gas flow at the inlet and outlet of the booster pump 2 can be adjusted by adjusting the opening of the gas flow valve 3. The other side of the electrostatic spray chamber 4 is equipped with a micropore array plate 5 and an adjustment electrode plate 6 in sequence from the inside of the electrostatic spray chamber 4 to the outside. The micropore array plate 5 is as shown in FIG. Figure 3 As shown, the micrometer hole array plate 5 adopts a silicon substrate and is coated with a super hydrophobic coating, such as polytetrafluoroethylene, on the surface of the micrometer hole array plate 5; the thickness of the micrometer hole array plate is 300 microns, and micrometer circular holes A are arranged in an array on the micrometer hole array plate 5. In order to avoid the fusion of liquid fuel when it is ejected from the micrometer circular hole A of the micrometer hole array plate 5, on the basis of spraying the super hydrophobic coating, an annular groove 17 is opened around the micrometer circular hole A, as shown in 4, under the action of the annular groove 17 and the super hydrophobic coating, when the liquid fuel ejected from the micrometer circular hole A overflows and is adsorbed on the orifice, the super hydrophobic coating will fully exert the hydrophobic property, and the diffused liquid fuel will be gathered back into the micrometer circular hole A. If the liquid fuel flow is large, when it exceeds the hydrophobic ability of the super hydrophobic coating, the annular groove 17 around the micrometer circular hole A will cache part of the liquid fuel, which serves the purpose of blocking diffusion, and finally avoids the mutual fusion of the liquid cone ejected from the micrometer circular hole A. The micrometer hole array plate 5 is connected to the negative pole of the negative high-voltage power supply, and the voltage range can be 1-30KV.

[0029] Adjust the plate 6 as Figure 5 As shown, the adjustment plate 6 is a silicon substrate with a thickness of 150 microns and the upper and lower surfaces are sprayed with conductive paint. At the same time, a micron hole B is opened on the adjustment plate 6; the micron hole B is set in a one-to-one correspondence with the micron hole A. Since the diameter ratio of the micron hole A to the micron hole B is 1:1.4, the diameter of the micron hole A is 100-150 microns, and the diameter of the micron hole B is 140-210 microns; the adjustment plate 6 is connected to the negative pole of another negative high-voltage power supply, and the voltage range can be 0-20KV. The voltage on the adjustment plate is always lower than the voltage of the micron hole array plate. By changing the size of the voltage of the two, the size of the liquid fuel atomized particles can be controlled, and then the entire combustion process can be precisely controlled.

[0030] like Figure 6 The collecting catalytic unit is arranged near the outlet of the feed pipe 12. The collecting catalytic unit is a collecting grid 7 made of metal such as stainless steel or copper. The collecting grid 7 is provided with square holes with a side length of 70 microns arranged in an array. The collecting grid 7 is grounded. By setting the collecting grid 7, the atomized fuel can be further gathered by the high voltage electric field to form a large number of charged micro droplets with excellent monodispersity.

[0031] A combustion grid 9 is installed inside the combustion catalytic chamber 13. Figure 7 As shown, the combustion grid 9 is made of metal such as stainless steel or copper and is sprayed with a combustion catalyst on the surface. The combustion grid 9 not only improves the reaction efficiency and reduces the ignition temperature, but also reduces the temperature of the entire burner, shortens the reaction time, and improves the combustion efficiency. At the same time, the combustion grid 9 is provided with regular hexagonal holes arranged in an array, and the side length of the regular hexagonal hole is 40 microns. The mesh of the combustion grid 9 is smaller than that of the collection grid 7, which not only allows the gas to be discharged smoothly, but also prolongs the residence time of the gas on the combustion grid, making the combustion more complete.

[0032] The working process of an electrostatic atomization micro burner based on a highly integrated micropore array of the present invention is further explained; when the voltage controller 1 is powered on, the booster pump 2 pressurizes the liquid in the fuel chamber 11, and the voltage at both ends of the booster pump 2 can be adjusted by the voltage controller 1, thereby adjusting its power, and the gas flow at the inlet and outlet of the booster pump 2 can be adjusted by adjusting the opening of the gas flow valve 3; the booster pump 2 injects air of a certain pressure into the fuel chamber 11 through the gas pipeline; there is a pressure difference between the gas pressure in the fuel chamber 11 and the external atmospheric pressure, and the liquid fuel contained therein overflows through the micron circular hole A of the micron hole array plate 5 after being subjected to the pressure difference and is adsorbed at the orifice, due to the micron circular hole A of the micron hole array plate 5 The outside of hole A is coated with super-hydrophobic coating and has concentric grooves to prevent liquid diffusion, thereby ensuring that the liquid cones will not merge with each other. Subsequently, the micrometer hole array plate 5 and the adjustment plate 6 are connected to the negative electrode of the negative high-voltage power supply, and the voltage of the adjustment plate 6 is less than the voltage of the micrometer hole array plate 5, forming a first-order potential difference. The fuel overflowing from the micrometer holes of the micrometer hole array plate 5 forms a cone under the action of the high-voltage electric field and gathers and shrinks when passing through the adjustment plate 6. Since the collecting grid 7 is grounded, there is a second-order potential difference between the adjustment plate 6 and it. Therefore, in the process of the fuel flowing out of the adjustment plate 6 to the collecting grid 7, the high-voltage electric field formed causes the gathered liquid cone to be atomized to form a large number of charged micro droplets with excellent monodispersity.

[0033] When the liquid fuel flowing out of the collecting grid 7 reaches the central intersection, it is mixed with the outside air brought by the axial flow fan 8 and brought into the combustion catalytic chamber 13. Since the combustion catalytic chamber is a variable diameter inlet with a gradually increasing diameter, the speed of the atomized fuel entering the combustion catalytic chamber 13 will be reduced, and the eddy current disturbance will greatly increase the contact time between the mixed gas and the combustion grid 9, thereby enhancing the catalytic effect. Finally, after the fuel and air are fully mixed, they enter the combustion outlet pipe 14 and are ignited by the ignition needle 10. Finally, the purpose of fully burning the liquid fuel after atomization is achieved.

[0034] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. An electrostatic atomization micro burner based on a highly integrated micropore array, characterized in that: The invention comprises a combustion catalytic chamber (13), the top and bottom of the combustion catalytic chamber (13) are respectively a combustion outlet pipe (14) and a fuel inlet pipe (18), the fuel inlet pipe (18) being connected to a feed pipe (12) and an air inlet pipe (15), respectively; a micrometer hole array electrostatic atomization unit and a collection catalytic unit are sequentially installed at the feed inlet of the feed pipe (12) from the outside to the inside; the micrometer hole array electrostatic atomization unit comprises an electrostatic spray chamber (4), one side of the electrostatic spray chamber (4) is connected to a fuel chamber (11) through a pipeline, and the other side of the electrostatic spray chamber (4) is sequentially installed from the inside of the electrostatic spray chamber (4) to the outside with a micrometer hole array plate (5) and an adjustment plate (6); the micrometer hole array plate (5) and the adjustment plate (6) are connected to the negative electrode of a negative high-voltage power supply to form a first-order potential difference; the collection catalytic unit is a collection grid (7), the collection grid (7) is grounded, and a second-order potential difference exists between the adjustment plate (6) and the collection grid (7); Two feed pipes (12) are provided; the two feed pipes (12) are arranged vertically with the air intake pipe (15); the air outlet end of the air intake pipe (15) is arranged opposite to the fuel inlet pipe (18); an axial flow fan (8) is installed in the air intake pipe (15); The collecting grid (7) is provided with square holes with a side length of 70 micrometers arranged in an array, and the atomized fuel is gathered by the collecting grid (7) using a high voltage electric field to form a large number of charged micro droplets with excellent monodispersity; A combustion grid (9) is installed inside the combustion catalytic chamber (13), and the combustion grid (9) is provided with regular hexagonal holes arranged in an array, and the side length of the regular hexagonal holes is 40 micrometers; the surface of the combustion grid (9) is sprayed with a combustion catalyst; When the liquid fuel flowing out of the collecting grid (7) reaches the central intersection, it is mixed with the outside air brought by the axial flow fan (8) and brought into the combustion catalytic chamber (13). Since the combustion catalytic chamber is a variable diameter inlet with a gradually increasing diameter, the speed of the atomized fuel entering the combustion catalytic chamber (13) will be reduced, and at the same time, eddy disturbances will be generated to greatly increase the contact time between the mixed gas and the combustion grid (9), thereby enhancing the catalytic effect. Finally, after the fuel and air are fully mixed, they enter the combustion outlet pipe (14) and are ignited by the ignition needle (10).

2. The electrostatic atomization micro burner based on a highly integrated micropore array according to claim 1, characterized in that: The voltage range of the negative electrode of the negative high-voltage power supply connected to the micrometer hole array plate (5) can be 1-30KV, the voltage range of the negative electrode of the negative high-voltage power supply connected to the adjustment plate (6) can be 0-20KV, and the voltage of the adjustment plate (6) is lower than the voltage of the micrometer hole array plate (5).

3. The electrostatic atomization micro burner based on a highly integrated micropore array according to claim 1, characterized in that: The micrometer hole array plate (5) adopts a silicon substrate and a super hydrophobic coating is coated on the surface of the micrometer hole array plate (5); Micrometer circular holes A are arranged in an array on the micrometer hole array plate (5).

4. The electrostatic atomization micro burner based on a highly integrated micropore array according to claim 3, characterized in that: The adjustment plate (6) is a silicon substrate with a thickness of 150 microns and conductive coatings are sprayed on the upper and lower surfaces. Meanwhile, micrometer circular holes B are opened on the adjustment plate (6); the micrometer circular holes B are arranged in a one-to-one correspondence with the micrometer circular holes A.

5. The electrostatic atomization micro burner based on a highly integrated micropore array according to claim 4, characterized in that: The diameter ratio of the micron circular hole A to the micron circular hole B is 1:1.4, and the diameter of the micron circular hole A is 100-150 microns.

6. The electrostatic atomization micro burner based on a highly integrated micropore array according to claim 5, characterized in that: An annular groove (17) is formed around the micrometer circular hole A.

Images