A plasma arc generating device with axial airflow control

Abstract

The present invention discloses a plasma arc generating device with axial airflow control, comprising a high-voltage electrode, a ground electrode, an insulating shell head, an arc gas inlet pipe, a core control gas inlet pipe, a bypass control gas inlet pipe, an insulating shell body, and an insulating shell tail; when arc generating gas, core control gas flow, and bypass control gas flow are introduced into the insulating shell, the high-voltage electrode and the ground electrode discharge the arc generating gas under the action of a voltage signal, thereby generating a plasma arc; in the process of generating a plasma arc, the flow rate of the core control gas flow and the bypass control gas flow is regulated, a pressure gradient is generated around the arc, the velocity field and pressure field of the electrode discharge are controlled, and the convection heat dissipation and radiation heat dissipation of the plasma arc are changed, thereby realizing the control of the arc morphology. The present invention is simpler, more flexible, more accurate, and has good real-time performance.

Description

Technical Field

[0001] The invention relates to the field of plasma arc generation, in particular to a plasma arc generation device with axial airflow control. Background Art

[0002] Plasma arc is a highly compressed arc flow with high energy density, high jet velocity, strong chemical activity, etc. It is often used in precision machining, waste gas treatment, medical applications, new material preparation, etc. In different applications, the requirements for arc shape, temperature and other characteristics are different. Therefore, how to achieve accurate and stable control of arc shape is the technical key to the above application scenarios.

[0003] At present, the main method of controlling the arc shape is magnetic arc control technology, which controls the arc shape by changing the distribution of the electromagnetic field. However, this control method generally requires changing the power supply or adding additional electromagnetic coils, which increases the technical cost of arc control to a certain extent. Summary of the invention

[0004] The object of the present invention is to provide a plasma arc generating device with axial airflow control, comprising a high-voltage electrode, a grounding electrode, an insulating shell head, an arc gas inlet pipe, a core control gas inlet pipe, a bypass control gas inlet pipe, an insulating shell body, and an insulating shell tail.

[0005] The high voltage electrode and the grounding electrode are placed in the head of the insulating shell.

[0006] The high-voltage electrode lead-out end of the high-voltage electrode is connected to an external high-voltage power source.

[0007] The external high voltage power supply applies a voltage signal to the high voltage electrode.

[0008] A grounding electrode lead-out end of the grounding electrode is grounded.

[0009] The grounding electrode and the insulating shell head form a bypass control gas circuit.

[0010] The front end of the insulating shell body is fixed to the insulating shell head, and the rear end is fixed to the insulating shell tail. The three are combined to form an insulating shell.

[0011] The side wall of the insulating shell body is connected with an arc gas inlet pipe and a bypass control gas inlet pipe.

[0012] The arc gas inlet pipe and the bypass control gas inlet pipe are both communicated with the internal gas path of the insulating shell body, thereby forming an air flow path.

[0013] The arc gas inlet pipe is used for introducing arc generating gas.

[0014] The bypass control air inlet pipe is used to introduce bypass control airflow; the bypass control airflow is used for arc regulation;

[0015] The rear end of the insulating shell is connected to a core control air intake pipe;

[0016] The core control air inlet pipe is used to introduce the core control airflow; the core control airflow is used for arc regulation;

[0017] After the arc generating gas, core control gas and bypass control gas are introduced, the high voltage electrode and the grounding electrode discharge the arc generating gas under the action of the voltage signal, thereby generating a plasma arc.

[0018] In the process of generating plasma arc, the core control gas and the bypass control gas are regulated to change the radial pressure gradient, thereby changing the radial electromagnetic force to achieve the control of the arc.

[0019] Furthermore, it also includes a water cooling tank, a cooling water inlet pipe and a cooling water outlet pipe.

[0020] The water cooling groove is arranged inside the head of the insulation shell, the main body of the insulation shell, and the tail of the insulation shell.

[0021] The cooling water inlet pipe and the cooling water outlet pipe are connected to the rear side wall of the insulating shell and are connected to the water cooling tank.

[0022] Cooling water flows in from the cooling water inlet pipe, flows through the water cooling tank, and then flows out from the cooling water outlet pipe, thereby cooling the high voltage electrode and the grounding electrode.

[0023] Furthermore, the arc generating gas, the bypass control gas and the core control gas are the same gas.

[0024] Furthermore, the method of regulating the core control gas and the bypass control gas includes exhausting gas and supplying gas.

[0025] Furthermore, the method of regulating the core control gas and the bypass control gas also includes adjusting the gas type and the gas flow rate.

[0026] Furthermore, it also includes a DC power supply for supplying power to the plasma arc generating device.

[0027] Furthermore, the plasma arc generating device operates under an atmospheric pressure environment.

[0028] The technical effect of the present invention is unquestionable. The present invention respectively sets two axial gas paths for regulation in the middle high-voltage electrode and inside the outer shell of the arc generator. By changing the flow rate of the two regulating airflows, a pressure gradient is generated around the arc. By controlling the velocity field and the pressure field, the convective heat dissipation and radiation heat dissipation of the arc discharge are changed, thereby realizing the control of the arc morphology. Compared with the traditional regulation method, the operation of the present invention is simpler, more flexible, more accurate and has good real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A plasma arc generating device with axial airflow control;

[0030] Figure 2 A front view of a plasma arc generating device with axial gas flow control;

[0031] Figure 3 A top view of a plasma arc generating device with axial airflow control;

[0032] Figure 4 It is a left view of a plasma arc generating device with axial airflow control;

[0033] Figure 5 A three-dimensional diagram of a plasma arc generating device with axial gas flow control I;

[0034] Figure 6 A perspective view of a plasma arc generating device with axial gas flow control II;

[0035] Figure 7 A cross-sectional view I of a plasma arc generating device with axial gas flow control;

[0036] Figure 8 It is a cross-sectional view II of a plasma arc generating device with axial gas flow control;

[0037] Fig. 9 For bypass airflow control effect (air supply);

[0038] Fig.10 For bypass airflow control effect (extraction);

[0039] Fig.11 It is the effect of airflow control (air supply) at the core;

[0040] Fig.12 It is the effect of the airflow control at the core (air extraction);

[0041] In the figure, high-voltage electrode 1, ground electrode 2, high-voltage electrode lead-out terminal 3, ground electrode lead-out terminal 4, insulating shell head 5, arc gas inlet pipe 6, pole core control gas inlet pipe 7, bypass control gas inlet pipe 8, water cooling tank 9, cooling water inlet pipe 10, cooling water outlet pipe 11, insulating shell body 12, insulating shell tail 13 DETAILED DESCRIPTION

[0042] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0043] Embodiment 1:

[0044] See also Figures 1 to 8 A plasma arc generating device with axial airflow control includes a high voltage electrode 1, a ground electrode 2, an insulating shell head 5, an arc gas inlet pipe 6, a core control gas inlet pipe 7, a bypass control gas inlet pipe 8, an insulating shell body 12, and an insulating shell tail 13.

[0045] The high voltage electrode 1 and the grounding electrode 2 are placed in the insulating housing head 5 .

[0046] The high-voltage electrode lead-out terminal 3 of the high-voltage electrode 1 is connected to an external high-voltage power source.

[0047] The external high voltage power supply applies a voltage signal to the high voltage electrode 1.

[0048] The ground electrode lead-out terminal 4 of the ground electrode 2 is grounded.

[0049] The ground electrode 2 and the insulating housing head 5 form a bypass control gas circuit.

[0050] The front end of the insulating housing body 12 is fixed with the insulating housing head 5 , and the rear end is fixed with the insulating housing tail 13 , and the three are combined to form an insulating shell.

[0051] The side wall of the insulating housing body 12 is connected with an arc gas inlet pipe 6 and a bypass control gas inlet pipe 8 .

[0052] The arc gas inlet pipe 6 and the bypass control gas inlet pipe 8 are both in communication with the internal gas path of the insulating housing body 12, thereby forming an air flow path.

[0053] The arc gas inlet pipe 6 is used to introduce arc generating gas.

[0054] The bypass control air inlet pipe 8 is used to introduce bypass control airflow; the bypass control airflow is used for arc regulation;

[0055] The insulating housing tail 13 is connected to a pole core control air intake pipe 7;

[0056] The core control air inlet pipe 7 is used to introduce the core control airflow; the core control airflow is used for arc regulation;

[0057] After the arc generating gas, the core control gas and the bypass control gas are introduced, the high voltage electrode 1 and the ground electrode 2 discharge the arc generating gas under the action of the voltage signal, thereby generating a plasma arc.

[0058] In the process of generating plasma arc, the core control gas and the bypass control gas are regulated to change the radial pressure gradient, thereby changing the radial electromagnetic force to achieve the control of the arc.

[0059] The specific control principles are as follows:

[0060] 1. According to the radial momentum conservation equation: That is, the radial pressure gradient is balanced with the radial electromagnetic force exerted on the magnetic fluid. By controlling the airflow through the bypass and the pole core, the radial pressure gradient changes, causing the radial electromagnetic force exerted on the magnetic fluid to change, thereby achieving the effect of regulating the arc.

[0061] 2. According to the energy conservation equation, the generation and dissipation of heat sources reach a dynamic balance, that is, the main heat source Joule heat is balanced with radiation heat dissipation, convection heat dissipation, and conduction heat dissipation.

[0062] Among them, according to the developed arc model, there is no obvious radial enthalpy gradient at the junction of the thermal layer and the external flow, so the control of the airflow mainly plays a role in regulating the arc by affecting convective heat dissipation and radiative heat dissipation.

[0063] a. According to the expression of convection term, Affected by the air flow velocity; b. According to the Stefan-Boltzmann law, its absorption coefficient is proportional to the relative pressure, so the purpose of control can be achieved by controlling the air flow to change the air pressure distribution.

[0064] It also includes a water cooling tank 9, a cooling water inlet pipe 10 and a cooling water outlet pipe 11.

[0065] The water cooling groove 9 is arranged inside the insulating housing head 5 , the insulating housing body 12 , and the insulating housing tail 13 .

[0066] The cooling water inlet pipe 10 and the cooling water outlet pipe 11 are connected to the side wall of the rear portion 13 of the insulating shell and are connected to the water cooling tank 9 .

[0067] Cooling water flows in from the cooling water inlet pipe 10 , flows through the water cooling tank 9 , and then flows out from the cooling water outlet pipe 11 , thereby cooling the high voltage electrode 1 and the ground electrode 2 .

[0068] The arc generating gas, bypass control gas and core control gas are the same gas. There is no requirement for the gas type, such as argon, nitrogen, helium, etc.

[0069] The methods for regulating the core control gas and the bypass control gas include exhausting gas and supplying gas.

[0070] Methods for regulating the core control gas and the bypass control gas also include adjusting the gas type and the gas flow rate.

[0071] A DC power supply for powering the plasma arc generating device is also included.

[0072] The plasma arc generating device operates under an atmospheric pressure environment.

[0073] Embodiment 2:

[0074] A plasma arc generating device with axial airflow control comprises a high voltage electrode 1, a grounding electrode 2, an insulating shell head 5, an insulating shell body 12, and an insulating shell tail 13.

[0075] The high voltage electrode 1 and the grounding electrode 2 are placed in the insulating housing head 5 .

[0076] The high-voltage electrode lead-out terminal 3 of the high-voltage electrode 1 is connected to an external high-voltage power source.

[0077] The external high voltage power supply applies a voltage signal to the high voltage electrode 1.

[0078] The ground electrode lead-out terminal 4 of the ground electrode 2 is grounded.

[0079] The ground electrode 2 and the insulating housing head 5 form a bypass control gas circuit.

[0080] The front end of the insulating housing body 12 is fixed with the insulating housing head 5 , and the rear end is fixed with the insulating housing tail 13 , and the three are combined to form an insulating shell.

[0081] The insulating housing head 5, the insulating housing tail 13 and the insulating housing body 12 are all threadedly connected.

[0082] The side wall of the insulating housing body 12 is connected with an arc gas inlet pipe 6 and a bypass control gas inlet pipe 8 .

[0083] The arc gas inlet pipe 6 and the bypass control gas inlet pipe 8 are both in communication with the internal gas path of the insulating housing body 12, thereby forming an air flow path.

[0084] The arc gas inlet pipe 6 is used to introduce arc generating gas.

[0085] The bypass control air inlet pipe 8 is used to introduce bypass control airflow for arc regulation.

[0086] The insulating shell tail portion 13 is connected to a pole core control air inlet pipe 7 .

[0087] The core control air inlet pipe 7 is used to introduce the core control airflow for arc regulation.

[0088] After the arc generating gas, the core control gas and the bypass control gas are introduced, the high voltage electrode 1 and the ground electrode 2 discharge the arc generating gas under the action of the voltage signal, thereby generating a plasma arc.

[0089] In the process of generating plasma arc, the core control gas and the bypass control gas are regulated to change the radial pressure gradient, thereby changing the radial electromagnetic force to achieve the control of the arc.

[0090] Embodiment 3:

[0091] A plasma arc generating device with axial airflow control, the main contents of which are shown in Example 2, wherein the device also includes a water cooling tank 9, a cooling water inlet pipe 10 and a cooling water outlet pipe 11.

[0092] The water cooling groove 9 is arranged inside the insulating housing head 5 , the insulating housing body 12 , and the insulating housing tail 13 .

[0093] The cooling water inlet pipe 10 and the cooling water outlet pipe 11 are connected to the side wall of the rear portion 13 of the insulating shell and are connected to the water cooling tank 9 .

[0094] Cooling water flows in from the cooling water inlet pipe 10 , flows through the water cooling tank 9 , and then flows out from the cooling water outlet pipe 11 , thereby cooling the high voltage electrode 1 and the ground electrode 2 .

[0095] Embodiment 4:

[0096] A plasma arc generating device with axial gas flow control, the main contents of which are shown in Example 2, wherein the arc generating gas, the bypass control gas, and the core control gas are the same gas. There is no requirement for the gas type, such as: all are argon, nitrogen, helium, etc.

[0097] Embodiment 5:

[0098] A plasma arc generating device with axial airflow control, the main content of which is shown in Example 2, wherein the method of regulating the core control gas and the bypass control gas includes exhausting and delivering gas.

[0099] Embodiment 6:

[0100] A plasma arc generating device with axial airflow control, the main content of which is shown in Example 2, wherein the method of regulating the core control gas and the bypass control gas also includes adjusting the gas type and the gas flow rate.

[0101] Embodiment 7:

[0102] A plasma arc generating device with axial airflow control, the main content of which is shown in Example 2, wherein the device also includes a DC power supply for powering the plasma arc generating device.

[0103] Embodiment 8:

[0104] A plasma arc generating device with axial airflow control, the main content of which is shown in Example 2, wherein the plasma arc generating device operates under atmospheric pressure environment.

[0105] Embodiment 9:

[0106] A plasma arc generating device with axial airflow control, comprising:

[0107] 1: High voltage electrode. This part is a conductive metal electrode that generates arc plasma when a DC voltage is applied.

[0108] 2: Grounding electrode. This part is a conductive metal electrode, which sets the grounding condition.

[0109] 3: High voltage electrode lead-out terminal, used to connect high voltage power supply;

[0110] 4: Ground electrode lead-out terminal, used for grounding.

[0111] 5: Insulation shell head. It serves as the encapsulation and protection shell of the device and is combined with the grounding electrode to form a bypass control gas path.

[0112] 6: Arc gas inlet pipe. The arc generating gas is introduced to ionize between the two electrodes to generate a plasma arc.

[0113] 7: Pole core control air inlet pipe. The pole core control air flow is introduced to control the arc.

[0114] 8: Bypass control air inlet pipe. The bypass control air flow is used to control the arc.

[0115] 9: Water cooling tank. There is circulating cooling water inside to cool the electrode and relieve the heat load generated by long-term work.

[0116] 10: Cooling water inlet pipe. Introduce cooling water into the water cooling tank.

[0117] 11: Cooling water outlet pipe. The drain outlet of the water cooling tank allows water cooling to circulate.

[0118] 12: Insulating housing body. As the encapsulating protective housing of the device, it is used to fix and connect the arc gas inlet pipe and the bypass control gas inlet pipe.

[0119] 13: Insulation shell tail. As the encapsulation and protection shell of the device, it is used to fix and connect the pole core control air inlet pipe and the cooling water outlet and inlet pipes.

[0120] The device adopts a two-way axial gas path design of core and bypass to achieve real-time and precise control of the arc shape.

[0121] The device can meet the control requirements of different arc forms by controlling the flow rates of two control air flows.

[0122] The electrodes of the device are cooled by circulating water to reduce the heat load caused by long-term operation.

[0123] The two-way controlled airflow in the device can be in the form of air extraction or air delivery.

[0124] The device can generate plasma arcs with different parameters by changing different current parameters or different carrier gases.

[0125] The device is powered by direct current and is used under atmospheric pressure.

[0126] Embodiment 10:

[0127] An experiment of a plasma arc generating device with axial gas flow control is as follows:

[0128] The arc gas type is argon, and the arc gas flow rate is 0.2m / s. The control effects of bypass control gas flow and core control gas flow are shown respectively:

[0129] 1) Temperature control effect

[0130] A. Bypass airflow control effect Fig. 9 and Fig.10 As shown, it can be seen that bypass gas supply helps to compress the arc, and bypass gas extraction helps to disperse the arc.

[0131] B. The effect of the core airflow control is as follows Fig.11 and Fig.12 As shown, it can be seen that the pole core gas supply is helpful for arc compression, and the pole core gas extraction is helpful for arc extinguishing effect.

[0132] The experiment found that the control effect of bypass airflow control is more sensitive than the core control, so in the case, the core control airflow velocity is much greater than the bypass.

[0133] In addition, based on the parameters of this case, experiments have shown that for the bypass gas supply method of compressing the arc, the compression effect will tend to saturation after the bypass gas supply flow rate reaches 1m / s (5 times the arc generating gas flow rate), and the compression effect will be regionally saturated after the core gas supply reaches 10m / s (50 times the arc generating gas flow rate); if an arc extinguishing effect is required, the core gas extraction method can be considered to quickly extinguish the arc; if the effect of dispersing the arc is required, the bypass gas supply method can be considered.

Claims

1. A plasma arc generating device with axial airflow control, characterized in that: It comprises a high-voltage electrode (1), a grounding electrode (2), an insulating housing head (5), an arc gas inlet pipe (6), a core control gas inlet pipe (7), a bypass control gas inlet pipe (8), an insulating housing body (12), and an insulating housing tail (13); The high voltage electrode (1) and the grounding electrode (2) are placed in the head (5) of the insulating housing; The high-voltage electrode lead-out terminal (3) of the high-voltage electrode (1) is connected to an external high-voltage power source; The external high-voltage power supply applies a voltage signal to the high-voltage electrode (1). The grounding electrode lead-out end (4) of the grounding electrode (2) is grounded; The grounding electrode (2) and the insulating housing head (5) form a bypass control gas circuit; The insulating housing body (12) has a front end fixed to the insulating housing head (5), and a rear end fixed to the insulating housing tail (13), and the three together form an insulating housing; The side wall of the insulating housing body (12) is connected to an arc gas inlet pipe (6) and a bypass control gas inlet pipe (8); The arc gas inlet pipe (6) and the bypass control gas inlet pipe (8) are both in communication with the internal gas path of the insulating housing body (12), thereby forming an air flow path; The arc gas inlet pipe (6) is used to introduce arc generating gas; The bypass control air inlet pipe (8) is used to introduce bypass control airflow; the bypass control airflow is used for arc regulation; The rear portion (13) of the insulating housing is connected to a core control air intake pipe (7); The core control air inlet pipe (7) is used to introduce the core control airflow; the core control airflow is used for arc regulation; After the arc generating gas, the core control gas and the bypass control gas are introduced, the high voltage electrode (1) and the ground electrode (2) discharge the arc generating gas under the action of the voltage signal, thereby generating a plasma arc; In the process of generating plasma arc, the core control gas and the bypass control gas are regulated to change the radial pressure gradient, thereby changing the radial electromagnetic force to achieve the regulation of the arc; The arc generating gas, bypass control gas and core control gas are the same gas; The methods for regulating the core control gas and the bypass control gas include exhausting gas and supplying gas.

2. A plasma arc generating device with axial airflow control according to claim 1, characterized in that: It also includes a water cooling tank (9), a cooling water inlet pipe (10) and a cooling water outlet pipe (11); The water cooling groove (9) is arranged inside the insulating housing head (5), the insulating housing body (12), and the insulating housing tail (13); The cooling water inlet pipe (10) and the cooling water outlet pipe (11) are connected to the side wall of the rear portion (13) of the insulating housing and are connected to the water cooling tank (9); Cooling water flows in from the cooling water inlet pipe (10), flows through the water cooling tank (9), and then flows out from the cooling water outlet pipe (11), thereby cooling the high-voltage electrode (1) and the grounding electrode (2).

3. The plasma arc generating device with axial airflow control according to claim 1, characterized in that: Methods for regulating the core control gas and the bypass control gas also include adjusting the gas type and the gas flow rate.

4. The plasma arc generating device with axial airflow control according to claim 1, characterized in that: A DC power supply for powering the plasma arc generating device is also included.

5. The plasma arc generating device with axial airflow control according to claim 1, characterized in that: The plasma arc generating device operates under an atmospheric pressure environment.

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