CN111577561A - Device for improving jet intensity of annular electrode exciter and working method thereof - Google Patents

Abstract

The invention discloses a device for increasing the jet intensity of an annular electrode exciter and a working method thereof. The device comprises a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium and a high-voltage power supply, and the dielectric barrier discharge exciter includes an annular high-voltage electrode. and annular ground electrode, the plasma synthetic jet exciter includes an exciter cavity, a first electrode and a second electrode, a through hole is arranged between the upper and lower surfaces of the insulating medium, the annular high-voltage electrode is located on the upper surface of the insulating medium, and the annular ground electrode Located in the insulating medium, the first electrode and the second electrode respectively extend into the cavity of the exciter. The annular dielectric barrier discharge exciter of the present invention can generate subsonic jets, and the plasma synthetic jet exciter can generate supersonic jets. The coordinated use of the two types of exciters can realize three working modes, so that the aircraft in various speed states can be improved. For flow control, flexible use and wide application.

Description

A device for increasing the jet intensity of a ring electrode exciter and its working method

technical field

The invention belongs to the field of fluid control, and in particular relates to a device for increasing the jet intensity of a ring-shaped electrode exciter and a working method thereof.

Background technique

The control of the external flow field of the aircraft has very important practical application value. An efficient flow control system can not only significantly improve the working performance of the aircraft, but also save a lot of fuel consumption. This makes the flow control technology become the frontier and hotspot of fluid mechanics research. In flow control, plasma control, as a method of active flow control, has the advantages of no moving parts, simple structure, wide operating frequency bandwidth and fast response speed, and has received extensive attention from research institutions around the world. In particular, dielectric barrier discharge actuators and plasma synthetic jet actuators are suitable for active flow control of low-speed and supersonic vehicles, respectively. The dielectric barrier discharge exciter is composed of surface exposed electrodes, buried electrodes and intermediate insulating medium. A ring electrode dielectric barrier discharge exciter designed by Santhanakrishnan, the upper surface ring electrode is connected to the high voltage output terminal of the high voltage pulse power supply, and the lower surface ring electrode is connected to the ground terminal of the pulse power supply. When the voltage across the electrodes exceeds the breakdown voltage, the The air near the electrode is broken down and ionized to form a plasma. The charged particles in the plasma collide with neutral gas molecules to induce the macroscopic acceleration of the gas near the wall, forming a gas jet near the wall, which plays a role in flow control during the working process of the aircraft. effect.

However, due to the limitation of the working principle, the induced jet velocity of the dielectric barrier discharge exciter is not high (less than 30m/s), which is far from the jet velocity that can control the surface flow field of high-speed aircraft. In order to obtain a large-area, low-energy, high-density plasma jet suitable for high-speed aircraft flow control, a lot of research work has been carried out at home and abroad mainly on the structural parameters of the exciter, insulating medium, electrode material and shape. The main methods to improve the jet velocity are as follows: one is to optimize the structure of the exciter; the other is to use a three-electrode dielectric barrier discharge exciter to increase the jet velocity; The generation of area plasma can increase the jet velocity and thrust. However, the existing annular electrode dielectric barrier discharge exciter still has the problem of low jet intensity.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a device for increasing the jet intensity of a ring electrode exciter and a working method thereof.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A device for increasing the jet intensity of a ring electrode exciter, comprising a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium and a high-voltage power supply, the dielectric barrier discharge exciter includes a ring-shaped high-voltage electrode and a ring-shaped ground electrode, and the The plasma synthetic jet exciter includes an exciter cavity, a first electrode and a second electrode, a through hole is provided between the upper and lower surfaces of the insulating medium, the annular high-voltage electrode is located on the upper surface of the insulating medium, and the The annular ground electrode is located in the insulating medium, the central axis of the through hole passes through the central hole of the annular high voltage electrode and the annular ground electrode, the exciter cavity is connected to the lower surface of the insulating medium, and the through hole is connected to the annular ground electrode. The exciter cavity is connected, the first electrode and the second electrode respectively extend into the exciter cavity, and the high-voltage power supply supplies power for the dielectric barrier discharge exciter and the plasma synthetic jet exciter.

A device for increasing the jet intensity of a ring electrode exciter, comprising a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium and a high-voltage power supply, the dielectric barrier discharge exciter includes a ring-shaped high-voltage electrode and a ring-shaped ground electrode, and the The plasma synthetic jet exciter includes a first electrode and a second electrode, the upper and lower surfaces of the insulating medium are penetrated by the first hole and the second hole that communicate with each other, and the annular high-voltage electrode is located on the upper surface of the insulating medium , the annular ground electrode is located in the insulating medium, the first hole passes through the central hole of the annular ground electrode, the central axis of the first hole passes through the central hole of the annular high voltage electrode, and the second hole The inner cavity forms an exciter cavity, the first electrode and the second electrode respectively extend into the exciter cavity from an insulating medium, and the high-voltage power supply supplies power for the dielectric barrier discharge exciter and the plasma synthetic jet exciter.

Further, the central axis of the through hole or the first hole coincides with the central axis of the annular high voltage electrode and the annular ground electrode.

Further, the annular high voltage electrode and the annular ground electrode are placed in parallel.

Further, the outer diameter of the annular ground electrode is equal to the inner diameter of the annular high voltage electrode.

Further, the insulating medium and/or the material of the exciter cavity is polytetrafluoroethylene, ceramics or boron nitride.

Further, the materials of the annular high voltage electrode, the annular ground electrode, the first electrode and the second electrode are copper or tungsten.

Further, the insulating medium is cylindrical, with a bottom diameter of 30 mm and a height of 10 mm. The inner diameter of the annular ground electrode is 2 mm and the outer diameter is 10 mm. The inner diameter of the annular high voltage electrode is 10 mm and an outer diameter of 25 mm. The diameter of the through hole or the first hole is 1mm, the diameter of the exciter cavity is 4mm, the height is 5mm, the diameter of the first electrode and the second electrode is 0.5mm, and the distance is 1mm.

According to the working method of the device for increasing the jet intensity of the annular electrode exciter, the device is used for the flow control of the aircraft, and the working method includes three modes:

The first mode: when the aircraft is in subsonic flight, the dielectric barrier discharge exciter works, the plasma synthesis jet exciter is turned off, and the low-speed jet generated by the operation of the dielectric barrier discharge exciter can play a control role;

The second mode: when the aircraft is in transonic flight, the dielectric barrier discharge exciter is turned off, the plasma synthetic jet exciter works, and the high-speed jet generated by the operation of the plasma synthetic jet exciter can meet the needs of flow control;

The third mode: when the aircraft is in supersonic or hypersonic flight, the dielectric barrier discharge exciter and the plasma synthetic jet exciter work simultaneously to control the flow of the external flow field of the aircraft.

Compared with the prior art, the present invention has the following significant advantages:

(1) The present invention has no moving parts, has fast response speed, wide operating frequency and high reliability;

(2) The device has a simple structure, can be embedded on the surface of the aircraft, occupies a small space, and can be used for aircraft with various flight speeds. The jet velocity generated by the dielectric barrier discharge exciter can be used for low-speed aircraft flow control, plasma synthesis The velocity generated by the jet exciter can reach more than 300m/s, which can be used for the flow control of high-speed aircraft. The two kinds of exciters are used together to control the flow of hypersonic aircraft. The use is flexible and the application range is wide;

(3) No gas supply is required, the gas comes from the outside air, and the gas can be automatically backfilled under the action of the pressure difference, and the jets generated by the two plasma exciters belong to the zero-mass flux jets;

(4) Through the circuit design, the dielectric barrier discharge exciter and the plasma synthetic jet exciter can share a power supply, so that the two exciters can be better coordinated and controlled, and the jet generation process of the two can be synchronized.

Description of drawings

FIG. 1 is a schematic structural diagram of the first embodiment of the apparatus for increasing the jet intensity of the ring electrode exciter according to the present invention.

FIG. 2 is a schematic structural diagram of the second embodiment of the apparatus for increasing the jet intensity of the ring electrode exciter according to the present invention.

Fig. 3 is an axonometric view of the device of the present invention for increasing the jet flow intensity of the annular electrode dielectric barrier discharge exciter.

FIG. 4 is a top view of the device for increasing the jet intensity of the annular electrode dielectric barrier discharge exciter according to the present invention.

FIG. 5 is a side view of the device for increasing the jet intensity of the annular electrode dielectric barrier discharge exciter according to the present invention.

Figure 6 is a circuit diagram for realizing the synergistic effect of two kinds of exciters.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

The implementation of the present invention will be described in detail below with reference to specific embodiments.

Example 1

1, a device for increasing the jet intensity of a ring electrode exciter includes a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium 1 and a high-voltage power supply, and the dielectric barrier discharge exciter includes a ring-shaped high-voltage electrode 3 and a high-voltage power supply. An annular ground electrode 4, the plasma synthetic jet exciter includes an exciter cavity 2, a first electrode 5 and a second electrode 6, a through hole is formed between the upper and lower surfaces of the insulating medium 1, and the annular high voltage electrode 3 Located on the upper surface of the insulating medium 1, the annular grounding electrode 4 is located in the insulating medium 1, and the inner diameter of the annular grounding electrode 4 embedded in the insulating medium 1 should be larger than the diameter of the through hole to ensure that the annular grounding electrode 4 is not exposed. In the air, the central axis of the through hole passes through the central hole of the annular high voltage electrode 3 and the annular ground electrode 4, the exciter cavity 2 is connected to the lower surface of the insulating medium 1, and the through hole is connected to the excitation The exciter cavity 2 is connected, the first electrode 5 and the second electrode 6 respectively extend into the exciter cavity 2, and the high-voltage power supply supplies power for the dielectric barrier discharge exciter and the plasma synthetic jet exciter.

Example 2

With reference to Figures 2-5, a device for increasing the jet intensity of a ring electrode exciter includes a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium 1 and a high-voltage power supply, and the dielectric barrier discharge exciter includes a ring-shaped high-voltage electrode 3 and a ring-shaped ground electrode 4, the plasma synthetic jet exciter includes a first electrode 5 and a second electrode 6, the upper and lower surfaces of the insulating medium 1 are penetrated by the first and second holes that communicate with each other, the The annular high-voltage electrode 3 is located on the upper surface of the insulating medium 1, and the annular grounding electrode 4 is located in the insulating medium 1. The inner diameter of the annular grounding electrode 4 embedded in the insulating medium 1 should be larger than the diameter of the first hole to ensure the annular The ground electrode 4 is not exposed to the air, the first hole passes through the central hole of the annular ground electrode 4, the central axis of the first hole passes through the central hole of the annular high voltage electrode 3, and the inner cavity of the second hole The body forms an exciter cavity 2, the first electrode 5 and the second electrode 6 respectively protrude into the exciter cavity 2 from the insulating medium 1, and the high-voltage power supply is a dielectric barrier discharge exciter and a plasma synthetic jet Exciter powered.

Further, the central axis of the through hole or the first hole coincides with the central axis of the annular high voltage electrode 3 and the annular ground electrode 4 .

Further, the annular high voltage electrode 3 and the annular ground electrode 4 are placed in parallel.

Further, the outer diameter of the annular ground electrode 4 is equal to the inner diameter of the annular high voltage electrode 3 .

Further, the material of the insulating medium 1 and/or the exciter cavity 2 is polytetrafluoroethylene, ceramic or boron nitride.

Further, the materials of the annular high voltage electrode 3 , the annular ground electrode 4 , the first electrode 5 and the second electrode 6 are copper or tungsten.

Further, the insulating medium 1 is cylindrical, with a bottom diameter of 30 mm and a height of 10 mm. The inner diameter of the annular ground electrode 4 is 2 mm and the outer diameter is 10 mm. The inner diameter of the annular high voltage electrode 3 is 10 mm and the outer diameter is 25 mm. The diameter of the through hole or the first hole of the insulating medium 1 is 1 mm, the diameter of the exciter cavity 2 is 4 mm and the height is 5 mm, and the diameter of the first electrode 5 and the second electrode 6 is 0.5 mm and the distance is 1 mm.

The high-voltage power supply supplies power for the dielectric barrier discharge exciter and the plasma synthesis jet exciter. When the voltage between the annular high-voltage electrode 3 and the annular grounding electrode 4 reaches the breakdown voltage, plasma is generated on the surface of the insulating medium 1, and the plasma can induce the electrode ring The surrounding fluid flows in a direction perpendicular to the surface of the insulating medium 1, and at the same time generates a thrust opposite to the induced direction. When the voltage between the first electrode 5 and the second electrode 6 reaches the breakdown voltage, high-temperature and high-pressure plasma is generated in the exciter cavity 2. Under the action of the internal and external pressure difference, the gas in the cavity is rapidly ejected to form a vertical The high-speed jet on the surface of the insulating medium 1 acts on the aircraft together with the jet generated by the dielectric barrier discharge exciter.

In order to achieve synchronous power supply to the annular high voltage electrode 3 and the annular ground electrode 4 and the first electrode 5 and the second electrode 6, a circuit diagram is designed for the high voltage power supply, as shown in Figure 6, by controlling the switch of the IGBT transistor to adjust the overall power supply. discharge frequency. At the same time, the switches on each branch can control the dielectric barrier discharge exciter or the plasma synthetic jet exciter to act independently. The plasma synthetic jet exciter is realized by capacitive discharge.

Specifically, the DC power source E is connected to the IGBT switch, and the DC power source is converted into AC power through the control of the IGBT switch, and then the low-voltage pulse power source is converted into a high-voltage pulse power source through the transformer M. The first electrode 5 and the second electrode 6 in the cavity are powered. Therefore, the DC power supply E, the IGBT switch and the transformer M together constitute a high-voltage pulse power supply. Next, the circuit on the right will continue to be described. The high-voltage pulse power supply is connected in parallel with the two branches. The two branches are the dielectric barrier discharge exciter and the plasma synthetic jet exciter, respectively. In the branch where the dielectric barrier discharge exciter is located, the electrode ring DBD composed of the annular high voltage electrode 3 and the annular ground electrode 4, the resistor R2 and the switch S3 are connected in series. The resistor R2 is mainly used to protect the circuit and adjust the voltage. Similarly, in the branch where the plasma synthetic jet exciter is located, there are also a resistor R1, a capacitor C and a plasma synthetic jet exciter A. The capacitor C is connected in parallel with the exciter A, and then connected in series with the resistor R1. The capacitor C is mainly designed for the exciter to store and discharge the energy, and the resistor R1 is to protect the circuit and adjust the voltage. There is a switch in these two branches respectively, which is used to control their working states, so as to realize three working modes. The three operating modes are: the first mode dielectric barrier discharge exciter operating mode (S3 closed, S2 open), the second mode plasma synthesis jet exciter discharge mode (S3 open, S2 closed) and the third mode Jet enhancement mode (S3 closed, S2 closed).

The first mode: when the aircraft is in subsonic flight, the dielectric barrier discharge exciter works, the plasma synthesis jet exciter is turned off, and the low-speed jet generated by the operation of the dielectric barrier discharge exciter can play a control role;

The second mode: when the aircraft is in transonic flight, the dielectric barrier discharge exciter is turned off, the plasma synthetic jet exciter works, and the high-speed jet generated by the operation of the plasma synthetic jet exciter can meet the needs of flow control;

The third mode: when the aircraft is in supersonic or hypersonic flight, the dielectric barrier discharge exciter and the plasma synthetic jet exciter work simultaneously to control the flow of the external flow field of the aircraft.

The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. The device for improving the jet intensity of the annular electrode exciter is characterized by comprising a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium (1) and a high-voltage power supply, wherein the dielectric barrier discharge exciter comprises an annular high-voltage electrode (3) and an annular grounding electrode (4), the plasma synthetic jet exciter comprises an exciter cavity (2), a first electrode (5) and a second electrode (6), a through hole is formed between the upper surface and the lower surface of the insulating medium (1), the annular high-voltage electrode (3) is positioned on the upper surface of the insulating medium (1), the annular grounding electrode (4) is positioned in the insulating medium (1), the central axis of the through hole penetrates through the central holes of the annular high-voltage electrode (3) and the annular grounding electrode (4), and the exciter cavity (2) is connected with the lower surface of the insulating medium (1), the through hole is communicated with the exciter cavity (2), the first electrode (5) and the second electrode (6) respectively extend into the exciter cavity (2), and the high-voltage power supply supplies power to the dielectric barrier discharge exciter and the plasma synthetic jet exciter.

2. A device for improving the jet intensity of a ring electrode exciter is characterized by comprising a dielectric barrier discharge exciter, a plasma synthetic jet exciter, an insulating medium (1) and a high-voltage power supply, wherein the dielectric barrier discharge exciter comprises a ring-shaped high-voltage electrode (3) and a ring-shaped grounding electrode (4), the plasma synthetic jet exciter comprises a first electrode (5) and a second electrode (6), the upper surface and the lower surface of the insulating medium (1) are penetrated through by a first hole and a second hole which are communicated with each other, the ring-shaped high-voltage electrode (3) is positioned on the upper surface of the insulating medium (1), the ring-shaped grounding electrode (4) is positioned in the insulating medium (1), the first hole penetrates through the central hole of the ring-shaped grounding electrode (4), and the central axis of the first hole penetrates through the central hole of the ring-shaped high-voltage electrode (3), the inner cavity of the second hole forms an exciter cavity (2), the first electrode (5) and the second electrode (6) respectively extend into the exciter cavity (2) from the insulating medium (1), and the high-voltage power supply supplies power for the dielectric barrier discharge exciter and the plasma synthetic jet exciter.

3. Device for increasing the jet intensity of an annular electrode exciter according to claim 1 or 2, characterized in that the central axis of the through-hole or first hole coincides with the central axis of the annular high voltage electrode (3) and the annular ground electrode (4).

4. Device for increasing the jet intensity of a ring electrode exciter according to claim 3, characterized in that the ring-shaped high voltage electrode (3) and the ring-shaped ground electrode (4) are placed in parallel.

5. Device for increasing the jet intensity of a ring electrode exciter according to claim 3, characterized in that the outer diameter of the ring ground electrode (4) is equal to the inner diameter of the ring high voltage electrode (3).

6. Device for increasing the jet intensity of a ring electrode exciter according to claim 3, characterized in that the material of the insulating medium (1) and/or the exciter cavity (2) is polytetrafluoroethylene, ceramic or boron nitride.

7. Device for increasing the jet intensity of a ring electrode exciter according to claim 3, characterized in that the material of the ring high voltage electrode (3), the ring ground electrode (4), the first electrode (5) and the second electrode (6) is copper or tungsten.

8. The device for improving the jet intensity of the annular electrode exciter according to claim 3, characterized in that the insulating medium (1) is cylindrical, the bottom surface of the insulating medium is 30mm in diameter and 10mm in height, the annular grounding electrode (4) is 2mm in inner diameter and 10mm in outer diameter, the annular high-voltage electrode (3) is 10mm in inner diameter and 25mm in outer diameter, the through hole or the first hole of the insulating medium (1) is 1mm in aperture, the exciter cavity (2) is 4mm in diameter and 5mm in height, and the first electrode (5) and the second electrode (6) are 0.5mm in diameter and 1mm apart.

9. The method of operation of a device for increasing jet intensity of a ring electrode actuator according to any one of claims 1 to 8, wherein the device is used for flow control of an aircraft, the method comprising three modes:

in the first mode: when the aircraft flies at subsonic speed, the dielectric barrier discharge exciter works, the plasma synthetic jet exciter is closed, and low-speed jet flow generated by the work of the dielectric barrier discharge exciter can play a control role;

in the second mode: when the aircraft flies at transonic speed, the dielectric barrier discharge exciter is closed, the plasma synthetic jet exciter works, and high-speed jet flow generated by the working of the plasma synthetic jet exciter can meet the requirement of flow control;

in the third mode: when the aircraft flies at supersonic speed or hypersonic speed, the dielectric barrier discharge exciter and the plasma synthetic jet exciter work simultaneously to realize the flow control of the external flow field of the aircraft.

Images