Double-airflow sliding electric arc ignition stable combustion device

Abstract

The invention discloses a double-airflow sliding electric arc ignition stable combustion device, which belongs to the technical field of plasma application and comprises a high-voltage electrode, a ground electrode, a ceramic gas rotating ring, a pulse regulator and a fuel distributor. Discharge gas enters the inner cavity of the rear tailstock from the gas inlet, a pulse regulator is arranged in the inner cavity of the rear tailstock, and the discharge gas forms pulse gas flow with continuously changing flow after passing through the pulse regulator. Pulse airflow generates homodromous rotating airflow through the ceramic gas rotating ring and the ceramic plate on the high-voltage electrode to drive arc roots of the high-voltage electrode and the ground electrode to do repeated spiral motion, the fuel distributor divides fuel into two stages, and the two stages are ignited. The arc root repeatedly makes spiral motion on the high-voltage electrode under the action of pulse airflow, the arc root motion area is large, the electrode cooling effect is good, the sliding arc power is effectively improved, and the service life of the electrode is effectively prolonged. And the fuel distributor is assisted to ignite the fuel in a grading manner, so that large-volume high-energy ignition flame can be obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of plasma application, and in particular relates to a dual-airflow sliding arc ignition and combustion stabilization device. Background Art

[0002] As an emerging technology, gliding arc plasma is increasingly widely used. Due to its relatively simple occurrence process and the ability to produce a large number of active free radicals and high-energy electrons, it is widely used in the degradation of volatile organic compounds, treatment of high-concentration organic wastewater, degradation of dioxins in fly ash, and production of synthesis gas and hydrogen.

[0003] In recent years, as the calls for carbon reduction and energy conservation and emission reduction have become louder and louder, carbon-free energy has received more and more attention, and many emerging technologies have been used in the field of ignition and combustion. For example, ammonia, as a combustible fuel, is gradually replacing fossil fuels in many application scenarios. However, due to the slow ignition speed of ammonia, which is as slow as 7cm / s and the ignition point as high as 651°C, ammonia encounters many difficulties in the combustion field. Ammonia cannot be ignited by high-energy ignition like natural gas or oil. In many ammonia combustion applications, the combustion chamber is first heated to above 800 degrees Celsius by natural gas or electric heating, and then ammonia and air are put into the chamber in a certain proportion and a certain mixture, and ignited by the action of a high-energy igniter. This ignition method requires a lot of energy to preheat the furnace cavity, and the furnace baking time is as long as several hours, resulting in energy waste and slow production capacity startup.

[0004] At present, plasma ignition methods can be divided into direct current (DC) ignition, alternating current (AC) ignition, high energy ignition, pulse ignition, corona discharge ignition, microwave ignition, spark ignition, etc. These schemes have to consider the problem of electrode life. For example, direct current (DC) ignition, alternating current (AC) ignition, corona discharge ignition, and microwave ignition protect the electrode by reducing the power of the igniter. High energy ignition, pulse ignition, and spark ignition protect the electrode by intermittent ignition. The energy of these ignition methods is only between a few watts and tens of watts. The energy they generate is not enough to ignite fuels with high ignition points and slow ignition speeds, such as ammonia.

[0005] In order to improve the ignition characteristics, some existing technologies use multiple high-voltage electrodes or multiple ground electrodes. For example, the Chinese patent application with publication number CN 111120112 A discloses a multi-ground electrode sliding arc plasma igniter and an ignition method based on the secondary flow of the combustion chamber. By changing the number of original ground electrodes and using the pressure difference between the secondary flow of the combustion chamber and the flame tube to drive the sliding arc discharge, a certain ignition power supply can be used to generate multiple sliding arcs at the same time, which can increase the contact area between the plasma and the oil-gas mixture, increase the initial fire core size, and improve the ignition ability of the sliding arc plasma igniter. However, it still cannot completely solve the problems of low ignition energy, small ignition high temperature area, and only igniting easily combustible fuels.

[0006] In summary, a plasma igniter is needed that can solve the problems of low ignition energy, small area of ​​high temperature zone generated, and only being able to ignite fuels with low ignition point and slow flame propagation speed. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a dual-airflow sliding arc ignition and stabilization device, in which pulsed rotating airflows are introduced into the inner and outer sides of the high-voltage electrode which is most likely to burn. Under the action of the pulsed rotating airflow, the arc root of the high-voltage electrode performs radial repeated spiral motion, and the moving area of ​​the arc root of the high-voltage electrode is increased to reduce ablation and enhance the electrode cooling effect. In this way, the plasma power can be effectively improved to prevent ablation, and the electric power of a commonly used igniter can be increased from tens of watts or hundreds of watts to about five kilowatts, thereby obtaining a large-volume, high-density, and multi-active particle plasma.

[0008] The sliding arc breaks through the gas to form plasma. The general device only has one gas path outside the high-voltage electrode and the gas flow rate needs to match the power, so the amount of air activated by the plasma is limited. The present invention adopts a method of increasing the rotating airflow inside and outside the high-voltage electrode at the same time, so the plasma power can be significantly improved. The dual-path pulse rotating airflow can increase the amount of activated air to about 200L / min. While continuously generating a large volume of plasma for ignition, it will also generate a large number of active particles, thereby greatly improving the ignition and combustion-supporting characteristics of the igniter.

[0009] After the discharge gas passes through the pulse regulator, it forms a pulsed airflow with a constantly changing flow rate. The pulsed airflow passes through the ceramic cyclone ring and the ceramic plate in the high-voltage electrode to generate a co-directional rotating airflow to drive the arc roots of the high-voltage electrode and the ground electrode to perform repeated spiral motions. The fuel distributor divides the fuel into two levels, which are ignited in stages. In the present invention, the arc root repeatedly performs spiral motions on the high-voltage electrode under the action of the pulsed airflow. The arc root has a large motion area, and the electrode cooling effect is good, which effectively improves the sliding arc power and electrode life. With the aid of the fuel distributor to ignite the fuel in stages, a large volume and high energy ignition flame can be obtained.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] A dual-flow sliding arc ignition and stabilization device comprises a high-voltage electrode, a ground electrode, a ceramic cyclone ring, a pulse regulator, and a fuel distributor; the discharge gas enters the inner cavity of the rear tail seat from the air inlet, the inner cavity of the rear tail seat is equipped with a pulse regulator, the pulse regulator comprises a valve body, a valve core and a motor, the valve body is provided with a plurality of holes of different sizes, the valve core is provided with a gas regulating hole, the valve core rotates at a certain speed under the action of the motor, the holes on the valve core constantly overlap with the holes of different sizes on the valve body, and the air passes through the gas regulating hole of the valve core and then passes through the valve body in turn. The small holes, medium holes, large holes and extra-large holes on the rear tailstock form a fluctuating pulse airflow, the inner circle thread of the rear tailstock is threadedly connected to the ceramic cyclone ring, the ceramic cyclone ring is connected to the high-voltage electrode, the ground electrode support tube is threadedly connected to the outer circle of the rear tailstock, the ground electrode support tube is coaxially arranged with the high-voltage electrode, the ground electrode is threadedly connected to the inner circle of the ground electrode support tube, the fuel distributor is threadedly connected to the outer circle of the ground electrode support tube, the rear tailstock is installed on the rear seat, an outer tube is installed on the rear seat, the high-voltage wire is connected to the high-voltage electrode and is connected to the power supply through the high-voltage wire hole of the rear tailstock.

[0012] Furthermore, the high-voltage electrode is a hollow structure, and is connected to the inner cavity of the ceramic cyclone ring via a vent hole. A ceramic plate is built into the middle of the high-voltage electrode, and the ceramic plate has multiple cyclone holes, and the direction of the cyclone holes is consistent with the cyclone holes of the ceramic cyclone ring.

[0013] Furthermore, the high-voltage arc-starting end is a circular ring structure, and a cooling fin ring is provided on the outside of the high-voltage arc-starting end. After the pulse gas enters the ceramic cyclone ring, it is divided into two parts. One part flows along the outer wall of the high-voltage arc-starting end through the cyclone hole of the ceramic cyclone ring, and the other part first enters the inner cavity of the high-voltage electrode through the air hole of the high-voltage electrode, and under the action of the ceramic plate, a cyclone is formed to flow along the inner wall of the arc-starting end of the high-voltage electrode.

[0014] Furthermore, the airflow on the inner wall surface of the arc starting end of the high-voltage electrode is in the same direction as the airflow on the outer wall surface of the high-voltage electrode.

[0015] The high-voltage electrode and the ground electrode are arranged coaxially, and the gap between the outer diameter of the high-voltage electrode and the inner diameter of the ground electrode support tube is 1.5mm-4mm. The interior of the ground electrode has three structural features: a necked opening, a flat opening, and a flared opening. The axial distance between the necked opening and the high-voltage electrode is 20mm-30mm. The necked opening, the flat opening, the flared opening, and the high-voltage electrode are arranged in order from near to far according to the distance.

[0016] Furthermore, the fuel distributor is threadedly connected to the outer ring of the ground electrode support tube.

[0017] Furthermore, a plurality of inclined grooves are provided in the middle of the fuel distributor, and the angle between the inclined grooves and the central axis of the fuel distributor is 15°-75°. The fuel distributor is made of high temperature resistant metal.

[0018] Furthermore, a normally open plate hole is provided on the valve body, the rotation speed of the motor is adjustable, and the diameter of the gas regulating hole on the valve core is greater than or equal to the extra-large hole.

[0019] Further, the fuel enters the cavity between the tailstock and the rear tailstock from the fuel inlet, passes through the gas equalizing hole of the ground electrode support tube, and a part of it is ejected out of the igniter along the gap between the outer tube and the fuel distributor.

[0020] Furthermore, a portion of the fuel enters the inner side of the fuel distributor through the chute, and the fuel entering the inner side of the fuel distributor accounts for 10%-50% of the total flow.

[0021] Furthermore, the air passes through the branch path, and under the action of the ceramic cyclone ring and the first cyclone hole inside the high-voltage electrode, there is a rotating airflow on the inner and outer sides of the arc starting end of the high-voltage electrode, or two rotating airflows are respectively introduced into the inner and outer sides of the arc starting end of the high-voltage electrode.

[0022] The beneficial effects of the present invention are:

[0023] 1. The igniter of the present invention uses a specially designed annular electrode to introduce a rotating airflow into the inner and outer walls of the electrode. Under the action of a pulse regulator, the airflow moves radially in a spiral and axially reciprocating motion on the inner wall of the arc starting end of the high-voltage electrode, which can significantly improve the heat dissipation effect, enhance the stability of the arc and reduce ablation, thereby increasing the power of the sliding arc and thereby enhancing the plasma density, increasing the plasma temperature and volume and enhancing the ignition characteristics.

[0024] 2. The present invention adjusts the airflow through a built-in pulse regulator, which has the characteristics of compact structure and reliable operation. Since the pulse regulator is close to the cyclone outlet and the buffer area is small, the gas pulse characteristics can be more accurately transmitted to the inner and outer wall surfaces of the high-voltage electrode, which can increase the pulse frequency and realize small flow pulse regulation.

[0025] 3. The ground electrode of the present invention has three structural features: a narrowed mouth, a flat mouth and a widened mouth. The narrowed mouth combined with the flat mouth structural features can improve the stability of the arc, especially when the power reaches 5kW or above, the risk of arc breaking can be effectively avoided. The widened mouth feature mainly has the function of causing the discharge air to first pass through the narrowed mouth and then through the flat mouth to produce a certain acceleration effect, and a negative pressure zone will be formed at the widened position. The negative pressure zone will draw in the fuel on the outside of the ground electrode to form a stable combustion area, thereby improving the stability of the igniter.

[0026] 4. There is an inclined groove feature in the middle of the fuel distributor. Since the gap between the fuel distributor and the outer tube is smaller than the gap between the ground electrode support tube and the outer tube, there will be a process of pressure increase when the fuel flows from the large gap to the small gap. In this process, part of the fuel will enter the plasma discharge area from the inclined groove. Due to the structural characteristics of the inclined mouth, the passing fuel has a certain rotation effect to form turbulence, which can make the fuel and the discharge air mix well and be sucked by the ground electrode expansion to participate in the primary combustion. The fuel directly ejected from the gap between the fuel distributor and the outer tube is in a laminar state and is ignited by the primary combustion flame, and an axial large-scale flame can be obtained.

[0027] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 A schematic diagram of the main cross-sectional structure of a dual-airflow sliding arc ignition and combustion stabilization device according to an embodiment of the present invention is shown;

[0030] Figure 2 A schematic cross-sectional structure diagram of a dual-airflow sliding arc ignition and combustion stabilization device according to an embodiment of the present invention is shown;

[0031] Figure 3 A schematic diagram of a cross-sectional structure of a high voltage electrode according to an embodiment of the present invention is shown;

[0032] Figure 4 A schematic cross-sectional structure diagram of a pulse regulator according to an embodiment of the present invention is shown;

[0033] Figure 5 A top view of a valve body in a pulse regulator according to an embodiment of the present invention is shown;

[0034] Figure 6 A schematic cross-sectional structure diagram of a rear tailstock according to an embodiment of the present invention is shown;

[0035] Figure 7 A schematic diagram of an axonometric view of a rear tailstock according to an embodiment of the present invention is shown;

[0036] Figure 8A schematic diagram showing uniform pore distribution of an anode support tube according to an embodiment of the present invention is shown;

[0037] In the figure, the reference numerals are: 1, high-voltage electrode; 101, high-voltage arc starting end; 1011, cooling fin ring; 1012, inner wall surface; 1013, outer wall surface; 102, ceramic plate; 1021, first swirl hole; 103, high-voltage electrode seat; 1031, vent hole; 1032, high-voltage connecting hole; 1033, high-voltage electrode cavity; 1501, second swirl hole; 2, ground electrode; 201, shrinkage; 202, flat mouth; 203, expansion; 3, fuel distributor; 301, chute; 302, outer thread of ground electrode support tube; 4, pulse regulator; 401, valve body; 4011, plate hole; 4012, Threading hole; 4013, small hole; 4014, medium hole; 4015, large hole; 4016, extra-large hole; 402, motor; 403, valve core; 4031, gas regulating hole; 404, bracket; 5, outer tube; 6, ground electrode support tube; 601, gas equalizing hole; 7, rear tail stock; 701, inner cavity; 702, limiting step; 703, rear tail stock outer circle thread; 704, rear tail stock inner circle thread; 705, tail stock bottom plate; 706, high-voltage wire hole; 8, tail stock; 9, protective tube; 10, grounding pile; 11, air inlet; 12, fuel inlet; 13, sealing gasket; 14, high-voltage wire; 15, ceramic swirl ring. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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. 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.

[0039] It should be noted that the terms "first", "second" etc. in the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged in appropriate circumstances, so that the embodiments of the present application described here. In the present application, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal" etc. are based on the orientation or positional relationship shown in the accompanying drawings.

[0040] The present invention provides a dual-airflow sliding arc ignition and stabilization device, which can improve the ignition power of sliding arc plasma, increase plasma density and volume, increase plasma temperature, generate more active particles, divide the fuel into a central turbulent flow and a surrounding laminar flow through a fuel distributor, maximize the ignition energy, heat the outer laminar main fuel while igniting the main fuel, and finally achieve the purpose of igniting the flame-retardant fuel.

[0041] See also Figure 1-Figure 8 As shown, a dual-airflow sliding arc ignition and stabilization combustion device provided in this embodiment includes a high-voltage electrode 1, a ground electrode 2, a ceramic cyclone ring 15, a pulse regulator 4, and a fuel distributor 3.

[0042] Preferably, the high-voltage electrode 1 includes a high-voltage arc-starting end 101, a ceramic plate 102, and a high-voltage electrode seat 103. The high-voltage electrode seat 103 is threadedly connected to the ceramic cyclone ring 15. The high-voltage electrode seat 103 is threadedly connected to the high-voltage arc-starting end 101. The ceramic plate 102 is installed between the high-voltage electrode seat 103 and the high-voltage arc-starting end 101, wherein the high-voltage arc-starting end 101 is a circular ring structure, and a cooling fin ring 1011 is provided on the outside of the high-voltage arc-starting end 101. A first cyclone hole 1021 is provided on the ceramic plate 102, and the rotation direction of the first cyclone hole 1021 is the same as the rotation direction of the second cyclone hole 1501 on the ceramic cyclone ring 15.

[0043] Preferably, the discharge working position of the high-voltage electrode 1 is at the high-voltage arc starting end 101, and the high-voltage arc starting end 101 is annular, and the annular shape is divided into an inner wall 1012 and an outer wall 1013. The pulse airflow of the inner wall 1012 and the outer wall 1013 of the high-voltage electrode is derived from the same gas through the vent 1031, and can also be supplied by two gases separately.

[0044] Preferably, Figure 4 , Figure 5As shown, the pulse regulator 4 includes a valve body 401, a valve core 403 and a motor 402. The valve body 401 is circular with a circular groove in the middle. The valve core 403 is built in the circular groove. The valve core 403 is connected to the motor 402 through an axis. The motor 402 is fixed on a bracket 404. The bracket 404 is fixed on the valve body 401. A plurality of holes of different sizes are arranged on the groove in the middle of the valve body 401. There is a hole on the valve core 403. The valve core 403 rotates at a certain speed under the action of the motor 402. The hole on the valve core 403 is constantly in contact with the valve body 401. The holes of different sizes in the groove overlap, and the air passes through the gas regulating hole of the valve core 403 and then passes through the small hole 4013, the medium hole 4014, the large hole 4015, and the extra-large hole 4016 on the valve body in turn to form a fluctuating pulse airflow, wherein the distances from the centers of the small hole 4013, the medium hole 4014, the large hole 4015, and the extra-large hole 4016 to the center of the valve body 401 are equal, and there is a threading hole 4012 on the outer side of the central groove of the valve body 401, and the high-voltage wire 14 passes through the threading hole 4012 and the high-voltage wire hole 706 on the rear tail seat 7 to connect the power supply to the high-voltage electrode 1.

[0045] Preferably, the fuel distributor 3 can divide the fuel into central turbulence and outer horizontal flow through the inclined groove 301. The central turbulence can increase the mixing effect of air and fuel and enhance the combustion stability. The outer horizontal flow can delay the mixing time of air and fuel and increase the scale of the flame distribution in the axial direction.

[0046] Preferably, the high voltage electrode 1 and the ground electrode 2 are coaxially arranged, the gap between the outer diameter of the high voltage electrode 1 and the inner diameter of the ground electrode support tube 6 is 1.5mm-4mm, and the ground electrode 2 has three structural features of a contracted opening 201, a flat opening 201, and a flared opening 203.

[0047] Preferably, the fuel distributor 3 is threadedly connected to the outer ring of the ground electrode support tube 6, and a plurality of inclined grooves 301 are opened in the middle of the fuel distributor 3. The angle between the inclined grooves 301 and the central axis of the fuel distributor 3 is 15°-75°. The fuel distributor 3 is made of high temperature resistant metal.

[0048] Preferably, in addition to the small hole 4013 , the medium hole 4014 , the large hole 4015 , and the extra-large hole 4016 , the valve body also has a normally open plate hole 4011 , the speed of the motor 402 is adjustable, and the diameter of the gas regulating hole 4031 on the valve core 403 is greater than or equal to the extra-large hole 4016 .

[0049] Preferably, the fuel enters the cavity between the tailstock 8 and the rear tailstock 7 from the fuel inlet 12, passes through the gas equalizing hole 601 of the ground electrode support tube 6, and a portion of the fuel is ejected out of the igniter along the gap between the outer tube 5 and the fuel distributor 3. There are multiple inclined grooves 301 on the fuel distributor 3, and a portion of the fuel enters the inner side of the fuel distributor 3 through the inclined grooves 301. The fuel entering the inner side of the fuel distributor accounts for 10%-50% of the total flow.

[0050] Preferably, the air passes through a branch path, and under the action of the ceramic cyclone ring 15 and the first cyclone hole 1021, there are rotating airflows on both the inner and outer sides of the high-voltage electrode arc starting end 101. Alternatively, two rotating airflows can be introduced into the inner and outer sides of the high-voltage electrode arc starting end 101 respectively.

[0051] Among them, the discharge gas enters the inner cavity 701 of the rear tail seat 7 from the air inlet 11, and the air inlet 11 is installed on the outside of the tail seat bottom plate 705. The outside of the tail seat bottom plate 705 is provided with a grounding pile 10, and the grounding pile 10 is composed of a threaded hole and a screw. The inner cavity 701 of the rear tail seat 7 is equipped with a pulse regulator 4, and the pulse regulator 4 is installed on the limit step 702. The pulse regulator 4 includes a valve body 401, a valve core 403 and a motor 402. The valve body 401 is arranged with a plurality of holes of different sizes, and the valve core 403 has a hole. The valve core 403 rotates at a certain speed under the action of the motor 402, and the hole on the valve core 403 constantly coincides with the holes of different sizes on the valve body 401. After passing through the hole of the valve core 403, the air passes through the small hole 4013 and the middle hole 4013 on the valve body in turn. 14, large holes 4015 and extra large holes 4016 form fluctuating pulse airflow, the inner thread 704 of the rear tailstock is threadedly connected to the ceramic cyclone ring 15, the ceramic cyclone ring 15 is connected to the high-voltage electrode 1, the ground electrode support tube 6 is connected to the outer thread 703 of the rear tailstock, the ground electrode support tube 6 is coaxially arranged with the high-voltage electrode 1, the ground electrode 2 is threadedly connected to the inner thread of the ground electrode support tube 6, the fuel distributor 3 is threadedly connected to the outer thread of the ground electrode support tube 6, the rear tailstock 7 is installed on the rear seat 8, the rear seat 8 is installed with an outer tube 5, the high-voltage wire 14 is connected to the high-voltage electrode 1 and passes through the high-voltage wire hole 706 of the rear tailstock 7 to be connected to the power supply, compared with other pulse-free gas or external pulse gas regulation methods, the pulse regulator 4 of the present invention can make the arc root of the high-voltage electrode move axially and increase the arc root sweep area. Since the pulse regulator 4 is close to the gas outlet participating in the discharge, the buffering effect of the transmission channel on the fluctuating gas can be reduced, and the pulse effect is more obvious.

[0052] A part of the pulse air flow flowing out of the pulse regulator 4 enters the second cyclone hole 1501 of the ceramic cyclone ring 15 and flows out and flows along the outer wall of the high-voltage electrode 1. The angle between the second cyclone hole 1501 of the ceramic cyclone ring 15 and the axis is 45°~60°. The other part first enters the high-voltage electrode inner cavity 1033 through the air vent 1031 of the high-voltage electrode, and the air flow then passes through the first cyclone hole 1021 of the ceramic plate 102. Under the action of the first cyclone hole 1021 on the ceramic plate 102, a rotating air flow is formed to flow along the inner wall of the arc starting end 101 of the high-voltage electrode. The air flow on the inner wall of the high-voltage electrode has the same rotation direction as the air flow on the outer wall of the high-voltage electrode.

[0053] The outer wall of the arc starting end 101 of the high voltage electrode is provided with a cooling fin ring 1011. The cooling fin ring 1011 can increase the contact area between the high voltage electrode 1 and the outside air, increase the cooling effect, and extend the life of the electrode.

[0054] The high voltage wire 14 is installed in the high voltage connection hole 1032 at the tail of the high voltage electrode 1 and passes through the high voltage wire hole 706 of the rear tailstock 7 to be connected to the power source.

[0055] Due to the physical properties of the sliding arc itself, the temperature of the high-voltage electrode arc root is high, which can reach about 3000K~5000K, and the arc also has a self-contraction characteristic. During discharge, the outer wall surface of the high-voltage electrode arc starting end 101 first forms an arc with the inner wall surface of the ground electrode support tube 6. Under the action of the arc self-contraction, the high-voltage electrode arc root quickly contracts from the outer wall surface of the high-voltage electrode arc starting end 101 to the inner wall surface 1012 of the high-voltage electrode arc starting end 101. Under the action of the pulsed rotating airflow on the inner wall surface 1012 of the high-voltage electrode arc starting end 101, the high-voltage electrode arc root makes a spiral motion on the inner wall surface 1012 of the high-voltage electrode arc starting end 101. When the flow rate of the rotating airflow on the inner wall surface of the high-voltage electrode arc starting end 101 increases, the rotation trajectory of the high-voltage electrode arc root deviates toward the opening direction of the high-voltage electrode arc starting end 101, and when the flow rate of the rotating airflow on the inner wall surface of the high-voltage electrode arc starting end 101 decreases, the rotation trajectory of the high-voltage electrode arc root shrinks and deviates in the opposite direction of the opening of the high-voltage electrode arc starting end 101. In this way, the swept area of ​​the high-voltage electrode arc root is increased from a point in a conventional reactor to the cylindrical surface inside the high-voltage electrode arc starting end 101. Thus, the position of electron emission can be continuously changed on the entire surface, and the position of the high-voltage electrode high heat point can be continuously changed in a spiral. The inside and outside of the high-voltage electrode arc starting end 101 are gas-cooled at the same time, which can better remove heat.

[0056] The ground electrode support tube 6 is connected to the outer thread 703 of the rear tailstock. The ground electrode support tube 6 is coaxially arranged with the high-voltage electrode 1. The ground electrode 2 is connected to the inner thread 704 of the ground electrode support tube. The ground electrode support tube 6 is installed with an equalizing ring 601. The fuel enters the interlayer between the tailstock 8 and the rear tailstock 7 from the fuel inlet 12, and flows evenly toward the outlet direction under the action of the equalizing ring 601. The rear tailstock 8 is threadedly connected to the protective tube 9. The protective tube 9 is installed in conjunction with the corrugated tube, and the high-voltage line 14 can be built into the corrugated tube, which can play an insulating and protective role.

[0057] The fuel distributor 3 is connected to the outer thread 302 of the ground electrode support tube, and the fuel distributor 3 is replaceable. A plurality of inclined grooves 301 are provided in the middle of the fuel distributor 3, and the angle between the inclined grooves 301 and the central axis of the fuel distributor 3 is 15°-75°. The fuel distributor 3 is made of high temperature resistant metal. Since the gap between the fuel distributor 3 and the outer tube 5 is smaller than the gap between the ground electrode support tube 6 and the outer tube 5, there will be a process of pressure increase when the fuel flows from the large gap to the small gap. In this process, part of the fuel will enter the plasma discharge area from the inclined groove 301. Since the inclined groove 301 has a certain angle with the center line, the fuel flowing inside through the inclined groove 301 has a certain rotation effect and forms turbulence, so that the fuel and the discharge air can be well mixed, and the ignition characteristics are enhanced. It is beneficial that a part of the fuel is sucked into the discharge area by the ground electrode expansion 203 to participate in the primary combustion, and the fuel directly ejected from the gap between the fuel distributor 3 and the outer tube 5 is in a laminar state, and is ignited again by the primary combustion flame, so that a large-scale axial flame can be obtained.

[0058] The rear tail seat 7 is mounted on the rear seat 8, and a sealing gasket 13 is used to seal between the rear tail seat 7 and the rear seat 8 to prevent fuel leakage. The sealing gasket 13 can be made of rubber or polytetrafluoroethylene. An outer tube 5 is mounted on the rear seat 8.

[0059] The ground electrode 2 has three structural features: a constricted opening 201, a flat opening 202, and a flared opening 203. The constricted opening 201 and the flat opening 202 structural features can improve the stability of the arc, especially when the power reaches 5kW or above, the risk of arc breaking can be effectively avoided. The flared opening 203 structural feature mainly functions in that the discharge air first passes through the constricted opening 201 and then through the flat opening 202, which will produce a certain acceleration effect. A negative pressure zone will be formed at the flared opening 203 position, and the negative pressure zone will suck the fuel outside the ground electrode 2 to form a stable combustion area, thereby improving the stability of the igniter. Preferably, the axial distance between the constricted opening and the high-voltage electrode is 20mm to 30mm, and the constricted opening 201, the flat opening 202, the flared opening 203 and the high-voltage electrode 1 are arranged in order from near to far according to the distance.

[0060] The invention continuously ignites the combustion-supporting fuel through high-power sliding arc plasma, thereby improving the ignition success rate of the ignition device. The igniter of the invention can be used for burners in application scenarios where the fuel ignition point is high and the flame propagation speed is slow.

[0061] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-flow sliding arc ignition and stabilization device, characterized in that: It includes a high-voltage electrode, a ground electrode, a ceramic cyclone ring, a pulse regulator, and a fuel distributor; the discharge gas enters the inner cavity of the rear tail seat from the air inlet, and the inner cavity of the rear tail seat is equipped with a pulse regulator. The pulse regulator includes a valve body, a valve core and a motor. The valve body is provided with a plurality of holes of different sizes, and the valve core is provided with a gas regulating hole. The valve core rotates at a certain speed under the action of the motor, and the holes on the valve core constantly overlap with the holes of different sizes on the valve body. After passing through the gas regulating hole of the valve core, the air passes through the small holes, the middle holes, and the holes on the valve body in turn. The large holes and the extra-large holes form fluctuating pulse airflow, the inner circle thread of the rear tailstock is connected to the ceramic cyclone ring thread, the ceramic cyclone ring is connected to the high-voltage electrode, the ground electrode support tube is connected to the outer circle thread of the rear tailstock, the ground electrode support tube is coaxially arranged with the high-voltage electrode, the ground electrode is connected to the inner circle thread of the ground electrode support tube, the fuel distributor is connected to the outer circle thread of the ground electrode support tube, the rear tailstock is installed on the rear seat, an outer tube is installed on the rear seat, and the high-voltage wire is connected to the high-voltage electrode and is connected to the power supply through the high-voltage wire hole of the rear tailstock.

2. A dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The high-voltage electrode is a hollow structure, and is connected to the inner cavity of the ceramic cyclone ring through a vent hole. A ceramic plate is built into the middle of the high-voltage electrode, and a plurality of first cyclone holes are arranged on the ceramic plate, and the direction of the first cyclone holes is consistent with the direction of the second cyclone holes of the ceramic cyclone ring.

3. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The high-voltage electrode includes a high-voltage electrode seat, a high-voltage arc starting end, and a ceramic plate. The high-voltage electrode seat is threadedly connected to a ceramic swirl ring. The high-voltage electrode seat is threadedly connected to the high-voltage arc starting end. The ceramic plate is installed between the high-voltage electrode seat and the high-voltage arc starting end. The high-voltage arc starting end is a circular ring structure, and a cooling fin ring is provided on the outside of the high-voltage arc starting end.

4. A dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The high-voltage electrode and the ground electrode are arranged coaxially, and the gap between the outer diameter of the high-voltage electrode and the inner diameter of the ground electrode support tube is 1.5mm-4mm. The interior of the ground electrode has three structural features: a necked opening, a flat opening, and a flared opening. The axial distance between the necked opening and the high-voltage electrode is 20mm-30mm. The necked opening, the flat opening, the flared opening, and the high-voltage electrode are arranged in order from near to far according to the distance.

5. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The fuel distributor is threadedly connected to the outer ring of the ground electrode supporting tube.

6. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: A plurality of inclined grooves are provided in the middle of the fuel distributor, and the angle between the inclined grooves and the central axis of the fuel distributor is 15°-75°. The fuel distributor is made of high temperature resistant metal.

7. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: There is also a normally open plate hole on the valve body, the speed of the motor is adjustable, and the diameter of the gas regulating hole on the valve core is greater than or equal to the extra-large hole.

8. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The fuel enters the cavity between the tailstock and the rear tailstock from the fuel inlet, passes through the gas equalizing holes of the ground electrode support tube, and a part of it is ejected out of the igniter along the gap between the outer tube and the fuel distributor.

9. The dual-flow sliding arc ignition and combustion stabilization device according to claim 6, characterized in that: A portion of the fuel enters the inner side of the fuel distributor through the chute, and the fuel entering the inner side of the fuel distributor accounts for 10%-50% of the total flow.

10. The dual-flow sliding arc ignition and combustion stabilization device according to claim 1, characterized in that: The air passes through the branch path, and under the action of the ceramic cyclone ring and the first cyclone hole inside the high-voltage electrode, there is a rotating airflow on the inner and outer sides of the arc starting end of the high-voltage electrode, or two rotating airflows are respectively introduced into the inner and outer sides of the arc starting end of the high-voltage electrode.

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