Vortex type plasma igniter for preventing electrode ablation based on vortex airflow discharge

Abstract

The invention discloses a vortex type plasma igniter for preventing electrode ablation based on vortex airflow discharge, and relates to the technical field of plasma generators, the vortex type plasma igniter comprises a shell, an air inlet structure, a high-voltage electrode, a swirler and a nozzle electrode, the air inlet structure, the high-voltage electrode, the swirler and the nozzle electrode are all arranged in the shell, and the high-voltage electrode is arranged in the shell. A first gas inlet channel is arranged in the gas inlet structure, a first gas channel is arranged between the high-voltage electrode and the shell, a vent hole is formed in the side wall of the swirler, airflow can form vortex airflow through the vent hole of the swirler, an outlet is formed between the nozzle electrode and the high-voltage electrode, and a second gas channel is formed between the nozzle electrode and the high-voltage electrode. The first gas inlet channel, the first gas channel, the vent hole and the outlet are all communicated. According to the vortex type plasma igniter for preventing electrode ablation based on vortex airflow discharge, the problem that the service life is short due to local ablation of the electrode can be solved.

Description

Technical Field

[0001] The invention relates to the technical field of plasma generators, in particular to a vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation. Background Art

[0002] During the operation of the plasma generator, the discharge arc generated between the electrodes has an extremely high temperature, which will cause serious damage to the electrode material and then cause local ablation. At the same time, ablation will change the electrode material and its conductive properties, so that the electrode cannot work normally, greatly affecting the service life of the electrode. The current density of the arc in the area attached to the electrode surface may exceed 10 8 A / m 2 The problem of shortened plasma generator life caused by severe local ablation of the electrode has always been an important factor affecting the long-term use and operation of the plasma generator. Summary of the invention

[0003] The purpose of the present invention is to provide a vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation, so as to solve the problem of short life caused by local ablation of the electrode.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a vortex-type plasma igniter for preventing electrode ablation based on vortex airflow discharge, comprising: a shell, an air intake structure, a high-voltage electrode, a cyclone and a nozzle electrode, wherein the air intake structure, the high-voltage electrode, the cyclone and the nozzle electrode are all arranged in the shell, a first air intake channel is arranged in the air intake structure, a first gas channel is arranged between the high-voltage electrode and the shell, a vent is opened on the side wall of the cyclone, and an air flow passing through the vent of the cyclone can form a vortex airflow, an outlet is arranged between the nozzle electrode and the high-voltage electrode, and the first air intake channel, the first gas channel, the vent and the outlet are all connected.

[0006] Preferably, the center line of the vent hole does not pass through the center line of the cyclone, and the center lines of the vent holes located on the same circumference are located in the same plane.

[0007] Preferably, one end of the high-voltage electrode extends into the air intake structure, and the air intake structure and the high-voltage electrode are detachably connected, and a second air intake channel is provided in the air intake structure, and the second air intake channel is respectively connected to the first air intake channel and the first gas channel.

[0008] Preferably, a connecting piece is provided on the outer side of the air intake structure, and the connecting piece is detachably connected to the air intake structure and the outer shell respectively, a first limiting step is provided on the outer side of the air intake structure, a second limiting step is provided on the inner side of the connecting piece, and a third limiting step is provided on the outer side of the connecting piece, the first limiting step and the second limiting step can contact each other, and the third limiting step and one end of the outer shell can contact each other.

[0009] Preferably, the connecting piece is made of non-conductive material.

[0010] Preferably, there are two cyclones, and a second gas channel is further provided between the housing and the high-voltage electrode, and the second gas channel is respectively connected to the vents of the two cyclones.

[0011] Preferably, a fourth limiting step is provided on the inner side of the outer shell, a fifth limiting step and a sixth limiting step are provided on the outer side of the high-voltage electrode, one of the cyclones is fixed by the fourth limiting step and the fifth limiting step, and the other cyclone is fixed by the sixth limiting step and the end of the nozzle electrode.

[0012] Preferably, the housing is detachably connected to the nozzle electrode.

[0013] Preferably, the housing, the air intake structure, the high-voltage electrode, the cyclone and the nozzle electrode are all coaxially arranged.

[0014] Preferably, the cyclone is made of non-conductive material; the air intake structure, the high-voltage electrode, the shell and the nozzle electrode are all made of conductive material.

[0015] Compared with the prior art, the present invention has achieved the following technical effects:

[0016] The vortex-type plasma igniter based on vortex-gas flow discharge to prevent electrode ablation of the present invention utilizes the influence of vortex-gas flow on the discharge arc, thereby affecting the ablation of the nozzle electrode from aspects such as the motion law of the discharge arc, the arc spatial distribution, and the change law of the arc length. By regulating the vortex-gas flow environment in the vortex-type plasma igniter based on vortex-gas flow discharge to prevent electrode ablation, the discharge characteristics of the discharge arc are changed, the ablation of the nozzle electrode is optimized and improved, the local ablation of the nozzle electrode is avoided, the nozzle electrode is ablated evenly, and the service life of the nozzle electrode is significantly extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only 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.

[0018] Figure 1 It is an axonometric diagram of a vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation of the present invention;

[0019] Figure 2 It is a cross-sectional view of a vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation of the present invention;

[0020] Figure 3 The invention discloses a vortex plasma igniter based on vortex gas flow discharge to prevent electrode ablation. Figure 1 ;

[0021] Figure 4 The invention discloses a vortex plasma igniter based on vortex gas flow discharge to prevent electrode ablation. Figure 2 ;

[0022] Figure 5 It is a cross-sectional view of the air intake structure of the present invention;

[0023] Figure 6 is a cross-sectional view of a connector of the present invention;

[0024] Figure 7 is a cross-sectional view of a cyclone of the present invention;

[0025] Figure 8 A cross-sectional view showing the positions of the vent holes of the cyclone of the present invention;

[0026] Fig. 9 is a cross-sectional view of a high voltage electrode of the present invention;

[0027] Fig.10 is a cross-sectional view of a housing of the present invention;

[0028] Fig.11 is a cross-sectional view of a nozzle electrode of the present invention;

[0029] Fig.12 This is a simulation diagram of the gas flow rate at the outlet of the nozzle electrode;

[0030] In the figure: 100-vortex plasma igniter based on vortex airflow discharge to prevent electrode ablation, 1-housing, 2-air inlet structure, 3-high voltage electrode, 4-cyclone, 5-nozzle electrode, 6-third limiting step, 7-first air inlet channel, 8-second air inlet channel, 9-first gas channel, 10-vent, 11-outlet, 12-connecting piece, 13-first limiting step, 14-second limiting step, 15-second gas channel, 16-fourth limiting step, 17-fifth limiting step, 18-sixth limiting step, 19-second inclined surface. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0032] The purpose of the present invention is to provide a vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation, so as to solve the problem of short life caused by local ablation of the electrode.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] like Figures 1 to 12 As shown, the present embodiment provides a vortex-type plasma igniter 100 for preventing electrode ablation based on vortex airflow discharge, comprising: a shell 1, an air intake structure 2, a high-voltage electrode 3, a cyclone 4 and a nozzle electrode 5, the air intake structure 2, the high-voltage electrode 3, the cyclone 4 and the nozzle electrode 5 are all arranged in the shell 1, a first air intake channel 7 is arranged at the center of the air intake structure 2, one end of the high-voltage electrode 3 extends into the interior of the air intake structure 2 and is threadedly connected to the air intake structure 2, a second air intake channel 8 is arranged in the air intake structure 2, and the second The number of air inlet channels 8 is not limited, a first gas channel 9 is provided between the high-voltage electrode 3 and the housing 1, a vent 10 is provided on the side wall of the cyclone 4, and the air flow can form a vortex air flow through the vent 10 of the cyclone 4, the nozzle electrode 5 is located between the housing 1 and the high-voltage electrode 3, the housing 1 is threadedly connected to the nozzle electrode 5, the nozzle electrode 5 is not in contact with the high-voltage electrode 3 and an outlet 11 is provided, and the first air inlet channel 7, the second air inlet channel 8, the first gas channel 9, the vent 10 and the outlet 11 are all connected. After the gas passes through the first air inlet channel 7, the second air inlet channel 8, the first gas channel 9 and the cyclone 4, a vortex with a significant gradient change will be generated between the nozzle electrode 5 and the high-voltage electrode 3.

[0035] Specifically, in this embodiment, a connecting piece 12 is provided on the outer side of the air intake structure 2, and the connecting piece 12 is threadedly connected to the air intake structure 2 and the outer shell 1 respectively. A first limiting step 13 is provided on the outer side of the air intake structure 2, a second limiting step 14 is provided on the inner side of the connecting piece 12, and a third limiting step 6 is provided on the outer side of the connecting piece 12. After the connecting piece 12 is threadedly connected to the air intake structure 2 and the outer shell 1 respectively, the first limiting step 13 and the second limiting step 14 are in contact, and the third limiting step 6 and one end of the outer shell 1 can be in contact.

[0036] In this embodiment, the cyclone 4 can fix the high-voltage electrode 3 and insulate it, and also provide a chamber for the introduction of airflow. The interior of the cyclone 4 is hollow, and the side wall of the cyclone 4 is provided with a plurality of vents 10 along the circumference of the cyclone 4, preferably six. There are two cyclones 4, and the rotation directions of the vortex airflow formed after the airflow passes through the two cyclones 4 are the same or opposite. A second gas channel 15 is also provided between the housing 1 and the high-voltage electrode 3, and the two ends of the second gas channel 15 are respectively connected to the vents 10 of the two cyclones 4.

[0037] In the present embodiment, a plurality of vents 10 are arranged along the circumference of the cyclone 4, and the center lines of the vents 10 do not pass through the center line of the cyclone 4. The angles between the center lines of the vents 10 and the center line of the cyclone 4 are equal, and the center lines of the vents 10 located on the same circumference are located in the same plane. The vents 10 of the present embodiment are arranged obliquely so that the airflow passing through the vents 10 can form a vortex airflow. After the airflow passes through the cyclone 4, it will rotate at a certain angle. The flow direction of the airflow before passing through the cyclone 4 is: from the air intake structure 2 toward the nozzle electrode 5, which is a straight streamline. After passing through the cyclone 4, it rotates at a certain angle and transforms into a vortex streamline. Therefore, the airflow velocity has a horizontal direction (the axial direction of the vortex plasma igniter 100 based on the vortex airflow discharge to prevent electrode ablation, that is, Figure 2 At the same time, since the gas flow has a certain velocity, after being transformed into a vortex, the gas velocity gradually decreases from the outside to the inside of the cross section at each cross section (perpendicular to the axis of the high-voltage electrode 3), as shown in FIG. Fig.12 As shown, at the outlet 11, the gas flow rate is the largest at the nozzle electrode 5, and the closer to the high-voltage electrode 3, the smaller the gas flow rate.

[0038] In this embodiment, a fourth limiting step 16 is provided on the inner side of the housing 1, a fifth limiting step 17 and a sixth limiting step 18 are provided on the outer side of the high-voltage electrode 3, one cyclone 4 is fixed by the fourth limiting step 16 and the fifth limiting step 17, and the other cyclone 4 is fixed by the sixth limiting step 18 and the end of the nozzle electrode 5, and the housing 1 and the high-voltage electrode 3, and the high-voltage electrode 3 and the nozzle electrode 5 are not in contact through the cyclone 4. In this embodiment, the two cyclones 4 can better limit the high-voltage electrode 3, so that the high-voltage electrode 3 is coaxial with the nozzle electrode 5.

[0039] In this embodiment, the nozzle electrode 5 is hollow, and the cross section of the inner wall of the nozzle electrode 5 (parallel to the axis of the high-voltage electrode 3) is sequentially provided with a first inclined surface, a straight surface, and a second inclined surface 19 from the end of the nozzle electrode 5 close to the air intake structure 2 to the end away from the air intake structure 2. The size of the first inclined surface gradually decreases from the end of the nozzle electrode 5 close to the air intake structure 2 to the end away from the air intake structure 2, and the size of the second inclined surface 19 gradually increases from the end of the nozzle electrode 5 close to the air intake structure 2 to the end away from the air intake structure 2. A discharge arc is formed between the second inclined surface 19 and the high-voltage electrode 3, and the second inclined surface 19 is conducive to the generation of a vortex discharge arc. After generating a gradient vortex airflow, the cyclone 4 reaches the gap between the high-voltage electrode 3 and the nozzle electrode 5. At the same time, the high-voltage electrode 3 is excited by an external high-voltage AC, and the air gap between the high-voltage electrode 3 and the nozzle electrode 5 generates a discharge breakdown, and the vortex airflow will be coupled with the discharge arc, thereby affecting the discharge characteristics of the discharge arc, and the arc is finally ejected from the outlet 11 of the nozzle electrode 5.

[0040] In this embodiment, the air intake structure 2, the high voltage electrode 3, the shell 1 and the nozzle electrode 5 are all made of conductive materials, preferably stainless steel; the connector 12 is made of non-conductive materials, preferably polytetrafluoroethylene; the cyclone 4 is made of non-conductive materials, preferably machinable ceramics. The connector 12 and the cyclone 4 are both non-conductive devices, and the air intake structure 2, the high voltage electrode 3, the shell 1 and the nozzle electrode 5 are all conductive devices. The air intake structure 2 or the high voltage electrode 3 is used to connect to the high voltage electricity, the high voltage electricity is greater than 5kV, and the shell 1 or the nozzle electrode 5 is used for grounding, so that a pressure difference is formed between the high voltage electrode 3 and the nozzle electrode 5.

[0041] In this embodiment, the air intake structure 2, the connecting piece 12, the high voltage electrode 3, the housing 1, the cyclone 4 and the nozzle electrode 5 are all coaxially arranged.

[0042] In this embodiment, the gas (air) enters the first air inlet channel 7 from one end of the air inlet structure 2, and passes through the second air inlet channel 8, the first gas channel 9, the inner side of the first cyclone 4, the air vent 10 of the first cyclone 4, the second gas channel 15, the air vent 10 of the second cyclone 4, the inner side of the second cyclone 4, and the outlet 11 in sequence.

[0043] In this embodiment, the vortex airflow has a transport effect on the active particles and heat energy generated by the discharge arc between the nozzle electrode 5 and the high-voltage electrode 3. The discharge arc rotates along the vortex direction on the surface of the nozzle electrode 5, and the root of the discharge arc moves periodically around the axis of the high-voltage electrode 3. The heat flow can be evenly distributed on the inner surface of the nozzle electrode 5, which can greatly reduce the effective specific heat flow, reduce the heat exchange between the discharge arc and the nozzle electrode 5, and the vortex airflow will take away part of the heat of the discharge arc during the rotation process.

[0044] At different vortex airflow velocities, the arc length shows a gradient distribution. The arc is continuously lengthened under the blowing of the airflow. The faster it moves outward, the harder it is to establish the arc. When the power supply cannot maintain the energy required to establish the arc, the arc goes out. As the vortex airflow velocity changes, the transport effect of active particles, the heat transfer rate around the arc, the time from the generation to the extinction of the arc, and the peak value of the arc length increase all change with the change of the flow velocity.

[0045] In the area with more discharge arc length per unit time, the number of interactions between the surface material of the nozzle electrode 5 and the discharge arc is greater, the heat exchange between the surface material of the nozzle electrode 5 and the electrode is more, and the ablation phenomenon is more serious. When the incoming flow velocity is changed, the vortex airflow velocity changes accordingly, the discharge arc is affected by the vortex airflow, the interaction between the surface material of the nozzle electrode 5 and the discharge arc changes, and then the spatial distribution characteristics of the ablation on the surface of the nozzle electrode 5 change.

[0046] At the same vortex airflow velocity, the discharge arc is affected by the transport action and rotates periodically with the vortex on the surface of the nozzle electrode 5, reducing the frequency of arc spots appearing at the same position on the electrode surface, thereby achieving the effect of reducing electrode ablation.

[0047] Under different vortex airflow velocities, the discharge arc exhibits different degrees of ablation at the same position of the nozzle electrode 5. Combined with the ablation characteristics of the nozzle electrode 5 under different incoming flow velocities, the airflow velocity is regulated within a unit time so that the discharge arc ablates uniformly along the spatial gradient distribution on the surface of the nozzle electrode 5, and then the purpose of regulating and improving the spatial distribution of electrode ablation and the ablation intensity in different regions is achieved by regulating the vortex airflow environment.

[0048] The discharge arc generated by the vortex-type plasma igniter 100 based on vortex airflow discharge to prevent electrode ablation in this embodiment rotates periodically, and the discharge is more stable. The vortex-type plasma igniter 100 based on vortex airflow discharge to prevent electrode ablation in this embodiment utilizes the influence of vortex airflow on the discharge of flowing gas, thereby affecting the motion law of the discharge arc, the spatial distribution of the arc, the intensity of the arc and the change law of the arc length. Under different working conditions, the electrode ablation can be uniformized, and the service life of the electrode can be significantly extended. The vortex airflow environment of the vortex-type plasma igniter 100 based on vortex airflow discharge to prevent electrode ablation in this embodiment makes the discharge arc present a spatial gradient distribution. By adjusting the flow rate of the vortex airflow in unit time, the discharge arc is uniformly ablated within different gradient ranges on the nozzle electrode 5, thereby reducing local ablation and significantly extending the service life of the electrode.

[0049] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A vortex-type plasma igniter based on vortex gas flow discharge to prevent electrode ablation, characterized in that: include: A shell, an air intake structure, a high-voltage electrode, a cyclone and a nozzle electrode, wherein the air intake structure, the high-voltage electrode, the cyclone and the nozzle electrode are all arranged in the shell, a first air intake channel is arranged in the air intake structure, a first gas channel is arranged between the high-voltage electrode and the shell, an air vent is opened on the side wall of the cyclone, and the air flow passing through the air vent of the cyclone can form a vortex air flow, an outlet is arranged between the nozzle electrode and the high-voltage electrode, and the first air intake channel, the first gas channel, the air vent and the outlet are all connected.

2. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1 is characterized in that: The center line of the vent hole does not pass through the center line of the cyclone, and the center lines of the vent holes located on the same circumference are located on the same plane.

3. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: One end of the high-voltage electrode extends into the air intake structure, and the air intake structure and the high-voltage electrode are detachably connected. A second air intake channel is provided in the air intake structure, and the second air intake channel is respectively connected to the first air intake channel and the first gas channel.

4. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: A connecting piece is provided on the outer side of the air intake structure, and the connecting piece is detachably connected to the air intake structure and the outer shell respectively. A first limiting step is provided on the outer side of the air intake structure, a second limiting step is provided on the inner side of the connecting piece, and a third limiting step is provided on the outer side of the connecting piece. The first limiting step and the second limiting step can contact each other, and the third limiting step and one end of the outer shell can contact each other.

5. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 4, characterized in that: The connecting piece is made of non-conductive material.

6. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: There are two cyclones, and a second gas channel is provided between the shell and the high-voltage electrode. The second gas channel is respectively connected to the vents of the two cyclones.

7. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 6, characterized in that: A fourth limiting step is provided on the inner side of the shell, and a fifth limiting step and a sixth limiting step are provided on the outer side of the high-voltage electrode. One of the cyclones is fixed by the fourth limiting step and the fifth limiting step, and the other cyclone is fixed by the sixth limiting step and the end of the nozzle electrode.

8. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: The housing is detachably connected to the nozzle electrode.

9. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: The shell, the air intake structure, the high-voltage electrode, the cyclone and the nozzle electrode are all coaxially arranged.

10. The vortex-type plasma igniter based on vortex airflow discharge to prevent electrode ablation according to claim 1, characterized in that: The cyclone is made of non-conductive material; the air intake structure, the high-voltage electrode, the shell and the nozzle electrode are all made of conductive material.

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