CN219536373U

CN219536373U - Pulse combustion driving plasma jet exciter and combustion chamber

Info

Publication number: CN219536373U
Application number: CN202320819121.3U
Authority: CN
Inventors: 陈海; 罗振兵; 周岩
Original assignee: National University of Defense Technology
Current assignee: National University of Defense Technology
Priority date: 2023-04-12
Filing date: 2023-04-12
Publication date: 2023-08-15
Anticipated expiration: 2033-04-12

Abstract

The utility model belongs to the field of jet flow exciters, and particularly relates to a pulse combustion driven plasma jet flow exciters and a combustion chamber, which comprise a shell, a valve, a positive electrode, a negative electrode and a pulse power supply, wherein a cavity is arranged in the shell in a hollow mode, a jet flow outlet and a mixed gas inlet which are communicated with the cavity are arranged on the shell, 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 with the pulse power supply.

Description

Pulse combustion driving plasma jet exciter and combustion chamber

Technical Field

The utility model belongs to the field of jet exciters, and particularly relates to a pulse combustion driving plasma jet exciter and a combustion chamber.

Background

The research of the flow control technology has important significance for improving the aerodynamic performance of the aircraft and improving the safety and operability of the aircraft.

Currently, active flow control techniques are receiving increasing attention. The design and research of active flow control actuators is one of the core problems of active flow control development, and jet type actuators including zero-mass and non-zero-mass jet and plasma type actuators represented by direct current glow discharge are two types of high-speed active flow control actuators which have appeared earlier and are most actively researched. The jet momentum of the plasma synthetic jet exciter is low; when the device is applied to a thin gas environment such as a high altitude or supersonic speed, a hypersonic flow field and the like, the performance of the exciter is obviously reduced.

Disclosure of Invention

The utility model aims to solve the technical problem of providing a pulse combustion driving plasma jet exciter with high jet flow velocity and a combustion chamber.

The utility model provides a pulse combustion driving plasma jet exciter which comprises a shell, a valve, a positive electrode, a negative electrode and a pulse power supply, wherein a cavity is arranged in the shell in a hollow mode, a jet outlet and a mixed gas inlet which are communicated with the cavity are arranged on the shell, 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 with the pulse power supply.

Further, 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 two corresponding sides of the cavity.

Still further, the cavity is cylindrical cavity, the efflux export sets up in cylindrical cavity one end, the mixed gas entry sets up in cylindrical cavity other end.

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

Still further, the casing includes main casing and apron, main casing one end is opened and is provided with the opening, and inside cavity is provided with the cavity, the apron with the opening sealing fit, the efflux export sets up on the apron.

Still further, the jet outlet is of the circular hole type, trumpet-shaped or Laval nozzle type.

Still further, the present utility model also includes an ignition electrode disposed within the cavity.

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

The utility model also provides a combustion chamber comprising the pulse combustion driven plasma jet exciter.

The plasma jet exciter has the beneficial effects that the valve and the mixed gas inlet are used for injecting mixed gas into the cavity, spark is generated through the positive electrode and the negative electrode to generate electricity and generate plasma, so that the temperature and the pressure of the gas in the cavity are quickly increased, high-energy particles are generated and the mixed gas is ignited, the mixed gas is combusted and sprayed out from the jet outlet at a high speed to generate high-speed jet, the combustion and the spraying processes are completed within a few milliseconds, negative pressure is formed in the cavity after the combustion is completed, and a next working period is started through injecting new mixed gas. The heat effect, impact effect and mixed gas combustion heating reaction of spark discharge can be utilized, so that the temperature and pressure of the gas in the cavity are quickly increased, the generated jet flow quantity is obviously higher than that of a pulse combustion exciter or a plasma synthetic jet flow exciter, and meanwhile, the problem that jet flow of the plasma synthetic jet flow exciter and the pulse combustion exciter is smaller in flow quantity is solved, and the environment adaptability is high. In addition, the mixed gas burns and combines the electrode to generate plasma, on one hand, the temperature and the pressure of the gas in the cavity are improved through the heat release of the mixed gas, and the jet speed is improved; on the other hand, the plasma discharge not only plays a role in ignition and combustion supporting, but also improves the temperature of the gas in the cavity.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a front cross-sectional view of the present utility model;

FIG. 3 is a graph of the exit velocity profile of the present utility model;

figure 4 is a graph of the mach number of the outlet jet of the present utility model.

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

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present utility model are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; the device can be mechanically connected, electrically connected, physically connected or wirelessly connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical solutions of the embodiments of the present utility model may be combined with each other, but it is necessary to be based on the fact that those skilled in the art can implement the technical solutions, and when the technical solutions are contradictory or cannot be implemented, the combination of the technical solutions should be considered as not existing, and not falling within the scope of protection claimed by the present utility model.

As shown in fig. 1-4, the utility model provides a pulse combustion driving plasma jet exciter, which comprises a shell, a valve, a positive electrode 2, a negative electrode 3 and a pulse power supply, wherein a cavity 11 is arranged in the shell in a hollow mode, a jet outlet 4 and a mixed gas inlet 5 which are communicated with the cavity 11 are arranged on the shell, the valve is arranged on the mixed gas inlet 5, the positive electrode 2 and the negative electrode 3 are arranged in the cavity 11, and the positive electrode 2 and the negative electrode 3 are connected with the pulse power supply.

The plasma jet exciter provided by the utility model has the advantages that the valve and the mixed gas inlet 5 are used for injecting mixed gas into the cavity 11, spark power generation is generated through the positive electrode 2 and the negative electrode 3, plasma is generated, the temperature and the pressure of the gas in the cavity 11 are quickly increased, high-energy particles are generated, the mixed gas is ignited, the mixed gas is combusted and sprayed out from the jet outlet 4 at a high speed, high-speed jet is generated, the combustion and spraying processes are completed within a few milliseconds, negative pressure is formed in the cavity 11 after the combustion is completed, and a next working cycle is started through injecting new mixed gas. The heat effect and impact effect of spark discharge and the combustion heating reaction of mixed gas can be utilized, so that the temperature and pressure of the gas in the cavity 11 are quickly increased, the generated jet flow quantity is obviously higher than that of a pulse combustion exciter or a plasma synthetic jet flow exciter, the problem that jet flow of the plasma synthetic jet flow exciter and the pulse combustion exciter is smaller is solved, and the environment adaptability is strong. In addition, the mixed gas combustion combines the electrode to generate plasma, on one hand, the temperature and the pressure of the gas in the cavity 11 are improved through the heat release of the mixed gas combustion, and the jet speed is improved; on the other hand, the plasma discharge not only plays a role of ignition and combustion supporting, but also increases the temperature of the gas in the cavity 11.

In one embodiment, the positive electrode 2 and the negative electrode 3 are disposed in the middle of the cavity 11, and the positive electrode 2 and the negative electrode 3 are disposed on two corresponding sides of the cavity 11, so as to achieve ignition in the middle of the cavity 11 filled with the mixed gas, and ensure that the combustion processes on two sides in the cavity 11 are synchronous.

In one embodiment, the cavity 11 is a cylindrical cavity, preferably, the whole shell is a cylinder, 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, so that the cavity 11 is conveniently refilled with the mixed gas through the mixed gas inlet 5 after being sprayed.

In one embodiment, the mixed gas inlet 5 is in a cylindrical cavity structure, and the diameter of the mixed gas inlet 5 is smaller than that of the cavity 11, and in this embodiment, the whole main housing 1 may be in a stepped shaft structure.

In one embodiment, the shell comprises a main shell 1 and a cover plate 7, one end of the main shell 1 is provided with an opening in an open mode, a cavity 11 is arranged in the cavity, the cover plate 7 is in sealing fit with the opening, the jet outlet 4 is arranged on the cover plate 7, and in the embodiment, the shell is arranged to be the main shell 1 and the cover plate 7, so that the shell is convenient to produce and process, and meanwhile equipment in the cavity 11 is convenient to install and maintain.

In one embodiment, the jet outlet 4 adopts a round hole type, has a simple and reliable structure, and can also adopt a horn shape or a Laval nozzle type to increase the jet speed.

Additionally, in a preferred embodiment, the housing is made of a superalloy. The mixed gas can be a gas mixture of hydrogen, acetylene, propane or other high-energy-density gas and forms a fuel/air mixture, and in addition, the mixed gas can directly adopt fuel on the aircraft. The valve can be an MEMS electronic valve or a mechanical valve, the positive electrode 2 and the negative electrode 3 are made of tungsten or tungsten alloy and are conical, so that the requirement on breakdown voltage is reduced, and the power and the volume of the required external power supply are reduced.

The positive electrode 2 and the negative electrode 3 are arranged to form a two-electrode ion body exciter, and the working principle is as follows:

firstly, a valve on a mixed gas inlet 5 is opened, mixed gas is filled into a cavity 11, after the mixed gas is filled into the cavity 11, the valve is closed and a pulse power supply is controlled to work, the pulse power supply generates spark through a positive electrode 2 and a negative electrode 3 in the cavity 11 to generate power generation and plasma, the temperature and the pressure of the mixed gas in the cavity 11 are quickly increased, high-energy particles are generated to ignite the mixed gas, the combusted mixed gas is sprayed out from a jet outlet 4 at a high speed, high-speed jet is generated, and the combustion process is completed within a few milliseconds. After the jet flow is finished, negative pressure is formed in the cavity 11, a valve is opened, new mixed gas enters the cavity 11, residual combustion products are discharged, and the next working cycle is started. Wherein. The mixed gas of the chamber 11 is overfilled each time to reduce the effect of residual gas. The control and regulation device can be a micro electromagnetic valve with accurate phase control capability or a passive mechanical valve or a fluid valve which works by means of pressure change of the cavity 11.

In one embodiment, the utility model further comprises an ignition electrode 6 arranged in the cavity 11, wherein the ignition electrode 6 can be additionally connected with a power supply, a three-electrode plasma exciter is formed by adding the ignition electrode 6, the three-electrode exciter can obviously reduce the maximum working voltage of the exciter, and a larger discharge peak current is obtained by adopting a larger discharge capacitor, so that the energy conversion efficiency of the capacitor to spark arc is improved, and the working performance of the exciter is improved.

The embodiment forms a three-electrode plasma exciter, and compared with a two-electrode plasma exciter, an ignition electrode is added, and the working principle is as follows:

the working principle is different from that of the two-electrode plasma exciter, in that when the positive electrode 2 and the negative electrode 3 are ignited, a plasma conducting channel is formed between the electrodes by discharging of the ignition electrode 6, the positive electrode 2 and the negative electrode 3 are triggered to discharge to generate plasma, and the working process is the same as that of the two-electrode plasma exciter. Experiments show that the gas temperature of the heating cavity of the three-electrode plasma exciter is approximately 1000K, the synthetic jet velocity exceeds 500m/s, compared with the two-electrode plasma exciter, the air breakdown voltage is reduced to 0.8kV/mm from 3kV/mm under the atmospheric pressure condition, the energy conversion efficiency is improved by about 4 times, the jet impulse is improved by 1 order of magnitude under the same discharge voltage condition, and the jet kinetic energy is improved by approximately 2 orders of magnitude. Compared with a two-electrode plasma exciter, the three-electrode plasma exciter can obviously reduce the maximum working voltage of the exciter, and a larger discharge peak current is obtained by adopting a larger discharge capacitor, so that the energy conversion efficiency of the capacitor to spark arc is improved, and the working performance of the exciter is improved.

As shown in fig. 3 and 4, the discharge time and the gas heating power density of the two kinds of exciters are consistent with the size and structure of the exciters, and it can be seen from the curve in fig. 3 that the combustion-driven plasma jet exciters have higher jet speeds than the plasma synthetic jet exciters under the condition that the discharge time and the gas heating power density are unchanged, and from the curve in fig. 4 that the combustion-driven plasma jet exciters have higher mach numbers than the plasma synthetic jet exciters under the condition that the discharge time and the gas heating power density are unchanged.

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, the positive electrode 2 and the negative electrode 3 are arranged on two corresponding sides of the cavity 11, 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, and the positive electrode 2, the ignition electrode 6 and the negative electrode 3 are distributed at 90 degrees in sequence so as to facilitate interaction of the three.

The utility model also provides a combustion chamber which comprises the pulse combustion driving plasma jet exciter.

What is not described in detail in this specification is prior art known to those skilled in the art.

Claims

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.