CN219536373U - Pulse combustion driving plasma jet exciter and combustion chamber - Google Patents

Abstract

The utility model belongs to the field of jet exciters, and in particular relates to a pulse-type combustion-driven plasma jet exciter and a combustion chamber, including a shell, a valve, a positive electrode, a negative electrode and a pulse power supply. There is a cavity, the casing is provided with a jet outlet and a mixed gas inlet communicating with the cavity, the valve is set on the mixed gas inlet, the positive electrode and the negative electrode are set in the cavity, and the positive The electrode and the negative electrode are connected to the pulse power supply. The plasma jet actuator provided by the utility model can produce a jet flow rate significantly higher than that of a pulsating combustion actuator or a plasma synthetic jet actuator. The problem of the small jet flow rate of the exciter and the pulsating combustion exciter has a strong environmental adaptability.

Description

A pulsed combustion-driven plasma jet actuator and combustion chamber

technical field

The utility model belongs to the field of jet exciters, in particular to a pulse-type combustion-driven plasma jet exciter and a combustion chamber.

Background technique

The study of flow control technology is of great significance for improving the aerodynamic performance of the aircraft, improving the safety and maneuverability of the aircraft.

At present, active flow control technology has received more and more attention. The design and research of active flow control actuators is one of the core issues in the development of active flow control. Jet actuators including zero-mass and non-zero-mass jets and plasma actuators represented by DC glow discharge are relatively new ones. Two types of high-speed active flow control actuators are the earliest and most actively studied. The jet flow rate of the plasma synthetic jet actuator is low; when it is applied in a thin gas environment such as high altitude or supersonic speed, hypersonic flow field, the performance of the actuator will be significantly reduced.

Utility model content

The technical problem to be solved by the utility model is to provide a pulse-type combustion-driven plasma jet exciter and a combustion chamber with fast jet velocity.

The utility model provides a pulse-type combustion-driven plasma jet exciter, which includes a shell, a valve, a positive electrode, a negative electrode and a pulse power supply. The jet outlet and the mixed gas inlet of the cavity, the valve is arranged on the mixed gas inlet, the positive electrode and the negative electrode are arranged in the cavity, and the positive electrode and the negative electrode are connected to the pulse power supply.

Furthermore, the positive electrode and the negative electrode are arranged in the middle of the cavity, and the positive electrode and the negative electrode are arranged on corresponding two sides of the cavity.

Furthermore, the cavity is a cylindrical cavity, the jet outlet is set at one end of the cylindrical cavity, and the mixed gas inlet is set at the other end of the cylindrical cavity.

Furthermore, the mixed gas inlet is a cylindrical cavity structure, and the diameter of the mixed gas inlet is smaller than the diameter of the cavity.

Furthermore, the housing includes a main housing and a cover plate, one end of the main housing is opened and an opening is provided, and a cavity is provided in a hollow inside, the cover plate is in sealing fit with the opening, and the jet outlet set on the cover.

Furthermore, the jet outlet adopts a circular hole type, a trumpet shape or a Laval nozzle type.

Furthermore, the utility model also includes an ignition electrode arranged in the cavity.

Furthermore, the ignition electrode, the positive electrode and the negative electrode are arranged in the middle of the cavity, and the positive electrode and the negative electrode are arranged on the corresponding two sides of the cavity, and the ignition electrode is arranged on the side wall of the cavity, and is located between the positive electrode and the negative electrode. between the negative electrodes.

The utility model also provides a combustion chamber, which includes a plasma jet exciter driven by pulse combustion.

The beneficial effect of the utility model is that the plasma jet exciter provided by the utility model, the valve and the mixed gas inlet are used to inject the mixed gas into the cavity, and generate spark power and generate plasma through the positive electrode and the negative electrode, so that the cavity The temperature and pressure of the gas in the body rise rapidly, generating high-energy particles and igniting the mixed gas. The mixed gas burns and ejects from the jet outlet at high speed to generate a high-speed jet. The combustion and injection process is completed within a few milliseconds, and a negative pressure is formed in the cavity after the combustion is completed. , enter the next working cycle by injecting new mixed gas. In this way, the thermal effect and impact effect of spark discharge can be used to react with the combustion and heat generation of the mixed gas, so that the temperature and pressure of the gas in the cavity can rise rapidly, and the jet flow generated is significantly higher than that of the pulsating combustion actuator or the plasma synthetic jet actuator. At the same time, it overcomes the problem that the jet flow rate of the plasma synthetic jet actuator and the pulsating combustion actuator is relatively small, and has strong environmental adaptability. In addition, the mixed gas combustion of the utility model is combined with the electrode to generate plasma. On the one hand, the temperature and pressure of the gas in the cavity are improved through the heat release of the mixed gas, and the jet velocity is increased; effect, but also increase the temperature of the gas in the chamber.

Description of drawings

Accompanying drawing 1 is the structural representation of the utility model;

Accompanying drawing 2 is the front sectional view of the utility model;

Accompanying drawing 3 is the outlet jet velocity curve figure of the utility model;

Accompanying drawing 4 is the Mach number curve diagram of outlet jet flow of the present utility model.

In the figure, 1-main casing; 11-cavity; 2-positive electrode; 3-negative electrode; 4-jet outlet; 5-mixed gas inlet; 6-ignition electrode; 7-cover plate.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiment of the utility model are only used to explain the relationship between the components in a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In addition, in the present application, descriptions such as "first", "second" and so on are used for description purposes only, and should not be understood as indicating or implying their relative importance or implicitly indicating the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present utility model, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

In this utility model, unless otherwise specified and limited, the terms "connection" and "fixation" should be understood in a broad sense, for example, "fixation" can be a fixed connection, a detachable connection, or an integration; It can be a mechanical connection, an electrical connection, a physical connection or a wireless communication connection; it can be a direct connection or an indirect connection through an intermediary, and it can be an internal connection between two components or an interaction relationship between two components , unless expressly defined otherwise. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model according to specific situations.

In addition, the technical solutions of the various embodiments of the present invention can be combined with each other, but it must be based on the realization of those skilled in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered as the technical solution. Combination does not exist, nor is it within the scope of protection required by the utility model.

As shown in the accompanying drawings 1-4, the utility model provides a pulse type combustion driven plasma jet exciter, including a housing, a valve, a positive electrode 2, a negative electrode 3 and a pulse power supply, the housing is hollowly provided with A cavity 11, the casing is provided with a jet outlet 4 and a mixed gas inlet 5 communicating with the cavity 11, the valve is set on the mixed gas inlet 5, and the positive electrode 2 and the negative electrode 3 are set in the cavity body 11, and the positive electrode 2 and the negative electrode 3 are connected to the pulse power supply.

The plasma jet exciter provided by the utility model, the valve and the mixed gas inlet 5 are used to inject the mixed gas into the cavity 11, generate spark power and generate plasma through the positive electrode 2 and the negative electrode 3, so that the cavity 11 The temperature and pressure of the gas rise rapidly, generating high-energy particles and igniting the mixed gas. The mixed gas burns and ejects at high speed from the jet outlet 4 to generate a high-speed jet. The combustion and injection process is completed within a few milliseconds. After the combustion is completed, a gas is formed in the cavity 11 Negative pressure, enter the next working cycle by injecting new mixed gas. In this way, the thermal effect and impact effect of the spark discharge can be used to react with the combustion and heat generation of the mixed gas, so that the temperature and pressure of the gas in the cavity 11 can be rapidly increased, and the jet flow generated is significantly higher than that of the pulsating combustion actuator or the plasma synthetic jet excitation. At the same time, it overcomes the problem of small jet flow of the plasma synthetic jet actuator and the pulsating combustion actuator, and has strong environmental adaptability. In addition, the mixed gas combustion of the utility model is combined with the electrode to generate plasma. On the one hand, the temperature and pressure of the gas in the cavity 11 are improved through the heat release of the mixed gas combustion, and the jet velocity is increased; The combustion-supporting effect also increases the temperature of the gas in the cavity 11 simultaneously.

In one of the embodiments, the positive electrode 2 and the negative electrode 3 are arranged in the middle of the cavity 11, and the positive electrode 2 and the negative electrode 3 are arranged on the corresponding two sides of the cavity 11, so that the cavity 11 filled with the mixed gas Ignition is realized in the middle to ensure that the combustion processes on both sides in the cavity 11 are synchronized.

In one of the embodiments, the cavity 11 is a cylindrical cavity, preferably, the housing is a cylinder as a whole, the jet outlet 4 is set at one end of the cylindrical cavity, and the mixed gas inlet 5 is set At the other end of the cylindrical cavity, it is convenient to refill the cavity 11 with the mixed gas through the mixed gas inlet 5 after spraying.

In one of the embodiments, the mixed gas inlet 5 is a cylindrical cavity structure, and the diameter of the mixed gas inlet 5 is smaller than the diameter of the cavity 11. In this embodiment, the main casing 1 can adopt a stepped shaft as a whole. structure.

In one of the embodiments, the housing includes a main housing 1 and a cover plate 7, one end of the main housing 1 is open with an opening, and a hollow cavity 11 is provided inside, the cover plate 7 and the The opening is sealed and fit, and the jet outlet 4 is arranged on the cover plate 7. In this embodiment, by setting the shell as the main shell 1 and the cover plate 7, it is convenient for the production and processing of the shell, and at the same time it is convenient for the cavity 11 equipment installation and maintenance.

In one of the embodiments, the jet outlet 4 adopts a round hole type, which has a simple and reliable structure, and can also adopt a horn-shaped or Laval nozzle type to increase the jet velocity.

In addition, in a preferred embodiment, the shell is made of superalloy. The mixed gas can be a mixture of gases with high energy density such as hydrogen, acetylene or propane to form a fuel/air mixture. In addition, the mixed gas can directly use the fuel onboard the aircraft. The valve can be a MEMS electronic valve or a mechanical valve. The positive electrode 2 and the negative electrode 3 are made of tungsten or a tungsten alloy and are conical in order to reduce the requirement for breakdown voltage and reduce the power and volume of the required external power supply.

The positive electrode 2 and the negative electrode 3 of the utility model are arranged to form a two-electrode plasma exciter, and its working principle is:

First open the valve on the mixed gas inlet 5, fill the cavity 11 with the mixed gas, after the cavity 11 is filled with the mixed gas, close the valve and control the pulse power supply to work, the pulse power supply passes through the positive electrode 2 and the negative electrode 3 in the cavity Sparks are generated in 11 to generate electricity and generate plasma, so that the temperature and pressure of the mixed gas in the cavity 11 rise rapidly, and high-energy particles are generated to ignite the mixed gas, and the burned mixed gas is ejected from the jet outlet 4 at a high speed, generating a high-speed jet, burning The process is completed within milliseconds. After the jet flow is over, negative pressure is formed in the cavity 11, the valve is opened, new mixed gas enters the cavity 11 and the remaining combustion products are discharged, and the next working cycle is entered. in. The mixed gas of the chamber 11 is overfilled each cycle to reduce the influence of residual gas. Also by setting the control and adjustment device, the control and adjustment device can be a micro solenoid valve with precise phase control capability or a passive mechanical valve or a fluid valve that depends on the pressure change of the cavity 11 to work.

In one of the embodiments, the utility model also includes an ignition electrode 6 arranged in the cavity 11, the ignition electrode 6 can be connected to a power source, and by adding the ignition electrode 6, a three-electrode plasma exciter is formed, and the three-electrode excitation The exciter can significantly reduce the maximum working voltage of the exciter, and by using a larger discharge capacitor to obtain a larger discharge peak current, the energy conversion efficiency of the capacitor to the spark arc is improved, thereby improving the working performance of the exciter.

In this embodiment, a three-electrode plasma actuator is formed. Compared with the two-electrode plasma actuator, an ignition electrode is added, and its working principle is as follows:

The difference with the working principle of the two-electrode plasma exciter is that when the positive electrode 2 and the negative electrode 3 are ignited, the discharge of the ignition electrode 6 forms a plasma conductive channel between the electrodes, triggering the discharge of the positive electrode 2 and the negative electrode 3 to generate plasma , and the subsequent working process is the same as that of the two-electrode actuator. Experiments show that the gas temperature in the heating chamber of the three-electrode plasma actuator is close to 1000K, and the synthetic jet velocity exceeds 500m/s. Compared with the two-electrode plasma actuator, the breakdown voltage of air under atmospheric pressure is reduced from 3kV/mm to 0.8kV /mm, the energy conversion efficiency is increased by about 4 times. Under the same discharge voltage condition, the jet impulse is increased by 1 order of magnitude, and the jet kinetic energy is increased by nearly 2 orders of magnitude. Compared with the two-electrode plasma actuator, the three-electrode plasma actuator can significantly reduce the maximum operating voltage of the actuator, and by using a larger discharge capacitor to obtain a larger discharge peak current, the energy from the capacitor to the spark arc is improved. Conversion efficiency, thereby improving the working performance of the exciter.

As shown in Figure 3 and Figure 4, the discharge time and gas heating power density of the two exciters in the figure are consistent with the size and structure of the exciter. From the curves in Figure 3, it can be seen that the discharge time and gas heating power density are constant. Under the condition that the combustion-driven plasma jet actuator has a higher jet velocity than the plasma synthetic jet actuator, it can be seen from the curve in Fig. 4 that under the condition of constant discharge time and gas heating power density, the combustion-driven plasma Jet actuators have a higher Mach number than plasma synthetic jet actuators.

In a preferred embodiment, the ignition electrode 6, the positive electrode 2 and the negative electrode 3 are arranged in the middle of the cavity 11, and the positive electrode 2 and the negative electrode 3 are arranged on the corresponding two sides of the cavity 11, and the ignition electrode 6 is arranged in the cavity. The side wall of the body 11 is located between the positive electrode 2 and the negative electrode 3. The positive electrode 2, the ignition electrode 6 and the negative electrode 3 are distributed at 90° in order to facilitate the interaction between the three.

The utility model also provides a combustion chamber, which includes the above-mentioned pulsed combustion-driven plasma jet exciter.

The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Claims (9)

1. The utility model provides a pulse combustion drive plasma jet exciter, characterized by, includes casing, valve, positive electrode (2), negative electrode (3) and pulse power, the inside cavity of casing is provided with cavity (11), be provided with jet outlet (4) and mixed gas entry (5) of intercommunication cavity (11) on the casing, the valve sets up on mixed gas entry (5), positive electrode (2) and negative electrode (3) set up in cavity (11), just positive electrode (2) and negative electrode (3) with pulse power connects.

2. The pulse combustion driven plasma jet actuator according to claim 1, wherein the positive electrode (2) and the negative electrode (3) are arranged in the middle of the cavity (11), and the positive electrode (2) and the negative electrode (3) are arranged on two corresponding sides of the cavity (11).

3. The pulse combustion driven plasma jet actuator according to claim 1, wherein the cavity (11) is a cylindrical cavity, the jet outlet (4) is arranged at one end of the cylindrical cavity, and the mixed gas inlet (5) is arranged at the other end of the cylindrical cavity.

4. A pulsed combustion driven plasma jet actuator according to claim 3, characterized in that the mixed gas inlet (5) is of cylindrical cavity configuration, the diameter of the mixed gas inlet (5) being smaller than the diameter of the cavity (11).

5. The pulse combustion driven plasma jet actuator according to claim 1, wherein the housing comprises a main housing (1) and a cover plate (7), an opening is arranged at one end of the main housing (1), a cavity (11) is arranged in the interior of the main housing, the cover plate (7) is in sealing fit with the opening, and the jet outlet (4) is arranged on the cover plate (7).

6. The pulsed combustion driven plasma jet actuator of claim 1 wherein the jet outlet (4) is of the circular, horn or laval nozzle type.

7. A pulsed combustion driven plasma jet actuator according to any of claims 1-6, further comprising an ignition electrode (6) disposed within the cavity (11).

8. The pulse combustion driven plasma jet actuator according to claim 7, wherein the ignition electrode (6), the positive electrode (2) and the negative electrode (3) are arranged in the middle of the cavity (11), the positive electrode (2) and the negative electrode (3) are arranged on two corresponding sides of the cavity (11), and the ignition electrode (6) is arranged on the side wall of the cavity (11) and is positioned between the positive electrode (2) and the negative electrode (3).

9. A combustion chamber comprising a pulsed combustion driven plasma jet actuator according to any one of claims 1 to 8.