CN109724107B - Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma - Google Patents
Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma Download PDFInfo
- Publication number
- CN109724107B CN109724107B CN201811639692.9A CN201811639692A CN109724107B CN 109724107 B CN109724107 B CN 109724107B CN 201811639692 A CN201811639692 A CN 201811639692A CN 109724107 B CN109724107 B CN 109724107B
- Authority
- CN
- China
- Prior art keywords
- combustion chamber
- flame
- pressure pulsation
- plasma
- frequency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Fluidized-Bed Combustion And Resonant Combustion (AREA)
Abstract
A method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma relates to a method for suppressing pressure pulsation in a thermoacoustic oscillation phenomenon. The invention uses the side plasma as a dynamic and active mode to regulate and control the pressure pulsation state of the combustion chamber in the combustion process under certain working conditions. According to the invention, the plasma is generated by utilizing Dielectric Barrier (DBD) discharge on the flame side surface of the combustion chamber, the distance between the main heat release area of the flame and the outlet of the combustion chamber is changed by adjusting the flame concentration area, the length of a return path for reflecting pressure pulsation in the combustion chamber from the outlet of the combustion chamber is changed, and the phase difference between the pressure pulsation and the heat release rate of the flame is changed, so that the condition of originally meeting thermoacoustic oscillation is destroyed, and further the reduction and even disappearance of the pressure pulsation in the combustion chamber are realized.
Description
Technical Field
The present invention relates to a method of suppressing combustion pressure pulsations.
Background
Under certain operating conditions, some unexpected instability will occur inside the combustion chamber, i.e. when the relative phase between the sound pressure and the unsteady heat release is between +90 ° and-90 °, the energy of the combustion system will be amplified. If this amplified energy is greater than the energy dissipated at the combustion chamber boundary, the average net energy accumulated over one oscillation period of the combustion chamber increases, eventually leading to the occurrence of thermoacoustic oscillations. On one hand, the unstable phenomenon can promote the mixing of fuel and air, enhance the mixing effect and facilitate the combustion; on the other hand, however, this results in additional pressure, high amplitude oscillations of the flow field and flame, increased thermal load, increased pollutant generation, impaired proper operation of the combustor and system, and, in severe cases, damage and destruction of system components.
In the above formula, the particle velocity is expressed, the pressure is expressed, the density is expressed, the acoustic velocity is expressed, and the heat release rate per unit volume is expressed. The left term of the equation (LHS) describes the rate of change of the total acoustic energy (sum of potential and kinetic energy) in the volume V of the combustion chamber, the first term on the right of the equation (RHS) represents the energy exchange between the unstable heat release and acoustic disturbances, and the last term represents the energy loss due to factors such as the boundary surface of the combustion chamber. When the relative phase between the sound pressure and the unsteady heat release is between +90 degrees and-90 degrees, the energy of the system can be amplified. If the acoustic energy provided by unstable combustion is greater than the energy dissipated at the combustion chamber boundary, the average energy of one oscillation cycle of the combustion chamber increases and eventually leads to combustion instability.
The conventional control methods for the thermo-acoustic oscillation inside the combustion chamber can be mainly divided into two methods, namely active control and passive control. The passive control aims at the second item at the right end of the upper formula, the control degree is limited greatly, and the passive control is usually only effective under the operation condition within a certain range. The active control aims at the first item at the right end of the upper formula, namely, the actuator is used for controlling certain parameters of the combustion system so as to interfere the condition that the combination of heat release pulsation and acoustic disturbance causes thermoacoustic oscillation, and the method has the advantages of good system feedback, good control effect and strong adaptability; however, the conventional active control (such as mechanical valve) still has the problems of insufficient actuation frequency (usually less than 100Hz), large actuation time delay, and mechanical loss.
Disclosure of Invention
The invention provides a method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma, which aims to solve the technical problems of insufficient actuation frequency, large actuation time delay and mechanical loss of the conventional method for suppressing the combustion pressure pulsation.
The method for inhibiting the combustion pressure pulsation by the high-frequency excitation discharge side plasma comprises the following steps:
the annular DBD electrode is arranged on the side wall of the combustion chamber in a surrounding mode and is located at the periphery of flame in height, the annular DBD electrode is connected with the output end of a power supply outside the combustion chamber, combustible premixed gas is introduced into the combustion chamber and ignited, when a thermoacoustic oscillation phenomenon is generated in the combustion chamber and pressure pulsation is carried out to a certain degree, the power supply outside the combustion chamber is started, the annular DBD electrode is enabled to generate plasma discharge inside the combustion chamber and act on the side face of the flame which generates the thermoacoustic oscillation inside the combustion chamber, the discharge frequency of the plasma is adjusted to be integral multiple (1kHz-50kHz) of the flame pulsation frequency, meanwhile, the discharge intensity of the plasma is adjusted, and suppression of the pressure pulsation in the combustion chamber is achieved.
The invention generates plasma on the side surface of the flame of the combustion chamber to change the distance of the main flame heat release area (flame main body) relative to the outlet of the combustion chamber, namely, the length of a return path of pressure pulsation in the combustion chamber reflected from the outlet of the combustion chamber is changed, and the phase difference between the pressure pulsation and the heat release rate of the flame is changed. The thermo-acoustic oscillation condition satisfied between the original flame heat release and the original sound pressure is broken through, and the suppression of the pressure pulsation in the combustion chamber is further realized.
The invention has the advantages that: compared with the traditional active control mode such as mechanical valve and the like, the invention utilizes the plasma as a novel active control mode, and can perfectly solve the problems of frequency limitation, actuation time delay, mechanical loss and the like of the traditional active control mode due to the high-frequency actuation characteristic (usually, kilohertz) of the plasma. In the phenomenon, the flame in the combustion chamber can be obviously adsorbed near the electrode when the plasma is started, the flame form is stable, and the influence of airflow disturbance is small. By connecting different power supplies and adjusting different parameters, a series of effects of inhibiting and slowing down pressure pulsation of the combustion chamber with different influence degrees can be obtained. The method has good feedback regulation implementation conditions for dynamic combustion pressure pulsation, and realizes the suppression and slowing effects of the optimal pressure pulsation by regulating various relevant parameters.
The invention applies plasma discharge to the flame meeting the thermoacoustic oscillation condition in the combustion chamber at the side surface of the flame, and can obviously change the phase difference between the pressure pulsation and the heat release rate, thereby breaking the original formation condition meeting the thermoacoustic oscillation between the flame heat release and the sound pressure in the combustion chamber, realizing the slowing of the thermoacoustic oscillation phenomenon, inhibiting the pressure pulsation, and slowing the pressure pulsation amplitude to one tenth of the former.
Drawings
FIG. 1 is a schematic diagram of a method for suppressing combustion pressure pulsation by a medium-high frequency excited discharge-side plasma in a test;
fig. 2 is an enlarged view of region a in fig. 1.
Detailed Description
The first embodiment is as follows: the embodiment is a method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma, which is specifically carried out according to the following steps:
the annular DBD electrode is arranged on the side wall of the combustion chamber in a surrounding mode and is located at the periphery of flame in height, the annular DBD electrode is connected with the output end of a power supply outside the combustion chamber, combustible premixed gas is introduced into the combustion chamber and ignited, when a thermoacoustic oscillation phenomenon is generated in the combustion chamber and pressure pulsation is carried out to a certain degree, the power supply outside the combustion chamber is started, plasma discharge is generated by the annular DBD electrode inside the combustion chamber and acts on the side face of the thermoacoustic oscillation flame generated in the combustion chamber, the discharge frequency of the plasma is adjusted to be integral multiples (1kHz-50kHz) of the flame pulsation frequency, the discharge intensity of the plasma is adjusted, and suppression of the pressure pulsation in the combustion chamber is achieved.
The second embodiment is as follows: the first difference between the present embodiment and the specific embodiment is: the annular DBD electrode consists of a high-voltage electrode end, an insulating medium and a ground electrode end; the high-voltage electrode end is connected with the output end of a power supply outside the combustion chamber, the ground electrode end is grounded, the insulating medium is annularly attached to the inner wall of the combustion chamber, the high-voltage electrode end is annularly attached to the inner wall of the insulating medium, the ground electrode end is annularly attached to the inner wall of the insulating medium, the high-voltage electrode end is parallel to the ground electrode end, and the high-voltage electrode end is located above the ground electrode end. The rest is the same as the first embodiment.
The third concrete implementation mode: the present embodiment differs from the first or second embodiment in that: the power supply is a pulse power supply, the voltage is 0-10 kV, and the pulse repetition frequency can reach 3kHz at most. The others are the same as in the first or second embodiment.
The fourth concrete implementation mode: the difference between this embodiment mode and one of the first to third embodiment modes is: the power supply is an alternating current power supply, the output voltage is 0-30kV, and the frequency range is 1 kHz-100 kHz. The rest is the same as one of the first to third embodiments.
The fifth concrete implementation mode: the fourth difference between this embodiment and the specific embodiment is that: the power supply is a direct current alternating current coupling power supply, namely a power supply formed by superposing a high-frequency high-voltage alternating current component II on high-voltage direct current, wherein the power of the direct current power supply is 10kW, and the maximum current is 0.3A; the frequency of the alternating current power supply is 1 kHz-100 kHz, and the voltage is 0-30 kV. The rest is the same as the fourth embodiment.
The invention was verified with the following tests:
test one: the test is a method for suppressing combustion pressure pulsation by the cooperation of high-frequency excitation discharge central plasma and side plasma, as shown in fig. 1 and 2, and is specifically performed according to the following steps:
the method comprises the steps of arranging an annular DBD electrode 2 on the side wall of a combustion chamber 1 in a surrounding mode, enabling the annular DBD electrode 2 to be located at the periphery of a flame 7 in a height mode, enabling the annular DBD electrode 2 to be connected with the output end of a power supply 5 outside the combustion chamber 1, enabling combustible premixed gas 6 to be introduced into the combustion chamber 1 and ignited, starting the power supply 5 outside the combustion chamber 1 when a thermoacoustic oscillation phenomenon is generated in the combustion chamber 1 and pressure pulsation of a certain degree is accompanied, enabling the annular DBD electrode 2 to generate plasma discharge inside the combustion chamber 1 and act on the side face of the thermoacoustic oscillation flame 7 inside the combustion chamber 1, adjusting the discharge frequency of the plasma to be integral multiple of the flame pulsation frequency (1kHz-50kHz), adjusting the discharge intensity of the plasma, and achieving suppression of the pressure pulsation inside the combustion chamber 1.
The annular DBD electrode 2 consists of a high-voltage electrode end 2-1, an insulating medium 2-2 and a ground electrode end 2-3; the high-voltage electrode end 2-1 is connected with the output end of a power supply 5 outside the combustion chamber 1, the ground electrode end 2-3 is grounded, the insulating medium 2-2 clings to the inner wall of the combustion chamber 1 in an annular shape, the high-voltage electrode end 2-1 clings to the inner wall of the insulating medium 2-2 in an annular shape, the ground electrode end 2-3 clings to the inner wall of the insulating medium 2-2 in an annular shape, the high-voltage electrode end 2-1 is parallel to the ground electrode end 2-3, and the high-voltage electrode end 2-1 is positioned above the ground electrode end 2-3;
the power supply 5 is an alternating current power supply; no. 3 is an injection pipe, and No. 4 is a contraction part;
in the test, after the combustion chamber 1 generates certain degree of thermoacoustic oscillation, the power supply 5 is turned on to generate plasma at the annular DBD electrode 2 to act on the side surface of the pulsating flame 7, and the frequency of the plasma is adjusted to be integral multiple of the pulsation frequency of the flame, so that the flame 7 is influenced by the thermal effect, the chemical effect and the electromagnetic effect of the plasma, the influence of airflow disturbance on the flame 7 is reduced, and the heat release stability is correspondingly improved; and the heat release rule of the flame 7 is adjusted, so that the amplification degree of the pulse energy of the combustion chamber 1 is reduced, namely, a passage of which the flow field fluctuation influences the combustion heat release rate fluctuation is isolated, and further the reduction and even disappearance of the pressure pulsation in the combustion chamber 1 are realized.
Claims (6)
1. A method for suppressing combustion pressure pulsation by high-frequency excitation of discharge side plasma is characterized in that the method for suppressing combustion pressure pulsation by high-frequency excitation of discharge side plasma is carried out according to the following steps:
the annular DBD electrode is arranged on the side wall of the combustion chamber in a surrounding mode and is located at the periphery of flame in height, the annular DBD electrode is connected with the output end of a power supply outside the combustion chamber, combustible premixed gas is introduced into the combustion chamber and ignited, when a thermoacoustic oscillation phenomenon is generated in the combustion chamber and pressure pulsation is carried out, the power supply outside the combustion chamber is started, the discharge frequency of plasma is adjusted to be integral multiple of the pulsation frequency of the flame, the annular DBD electrode generates plasma discharge inside the combustion chamber and acts on the side face of the thermoacoustic oscillation flame generated inside the combustion chamber, the plasma adsorbs the flame at the position of the side wall of the combustion chamber, the flame heat release concentration area is changed, the phase difference between the pressure pulsation and the flame heat release rate is changed, and suppression of the pressure pulsation in the combustion chamber is achieved; adjusting the frequency, voltage or current amplitude of the plasma excitation power supply to realize combustion pressure pulsation mitigation or inhibition;
the height position of the annular DBD electrode is controllable, different discharge positions can enable the plasma to adsorb a flame main body at different wall surface electrodes, and the position of a flame heat release concentration area along the airflow direction is adjustable, so that the length of a pressure pulsation feedback path in a combustion chamber is adjustable, and the phase difference between the pressure pulsation and the heat release rate can be correspondingly adjusted;
the annular DBD electrode consists of a high-voltage electrode end, an insulating medium and a ground electrode end; the high-voltage electrode end is connected with the output end of a power supply outside the combustion chamber, the ground electrode end is grounded, the insulating medium is annularly attached to the inner wall of the combustion chamber, the high-voltage electrode end is annularly attached to the inner wall of the insulating medium, the ground electrode end is annularly attached to the inner wall of the insulating medium, the high-voltage electrode end is parallel to the ground electrode end, and the high-voltage electrode end is positioned above the ground electrode end; the annular DBD electrodes are uniformly arranged around the flame at intervals along the flowing direction of the premixed gas, so that the adsorption effect of the flame at different heights is realized.
2. The method according to claim 1, wherein the plasma generated by the annular DBD electrode acts on the side of the flame and affects the flame, and the input energy of the plasma reaches a certain degree, so that the main body of the flame can be adsorbed near the annular DBD electrode on the wall surface, the main heat release area of the flame changes, the length of the return path of the pressure pulsation in the combustion chamber is further changed, the phase difference between the pressure pulsation and the heat release rate is changed, the thermo-acoustic oscillation condition satisfied between the original heat release of the flame and the sound pressure is broken, and the suppression of the pressure pulsation in the combustion chamber is realized.
3. The method for suppressing the combustion pressure pulsation by the high-frequency excited discharge side plasma as claimed in claim 1, wherein the plasma has the advantages of adjustable input energy and no mechanical loss as an active control mode, and can better solve the problems of small action range and mechanical loss of the traditional control means.
4. The method according to claim 1, wherein the plasma discharge frequency is selected based on the consideration that the main frequency of the combustion chamber thermo-acoustic oscillation is 50 Hz-200 Hz, and the plasma discharge frequency is set to be 1kHz-50kHz, so that the plasma can effectively adsorb the main part of the flame around the wall surface annular DBD electrode.
5. The method according to claim 1, wherein the power supply is a pulse power supply, the voltage is 0-10 kV, and the pulse repetition frequency is up to 3 kHz.
6. The method according to claim 1, wherein the power source is an AC power source, the output voltage is 0-30kV, and the frequency range is 1-100 kHz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811639692.9A CN109724107B (en) | 2018-12-29 | 2018-12-29 | Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811639692.9A CN109724107B (en) | 2018-12-29 | 2018-12-29 | Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109724107A CN109724107A (en) | 2019-05-07 |
| CN109724107B true CN109724107B (en) | 2021-04-23 |
Family
ID=66297975
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811639692.9A Active CN109724107B (en) | 2018-12-29 | 2018-12-29 | Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109724107B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111751110B (en) * | 2020-07-04 | 2021-05-14 | 西北工业大学 | Carbon fiber heat release sound production device for oscillation combustion of solid propellant |
| CN112253317A (en) * | 2020-11-10 | 2021-01-22 | 上海电气燃气轮机有限公司 | Closed-loop combustion control system and control method thereof |
| CN112683542A (en) * | 2020-12-15 | 2021-04-20 | 上海交通大学 | Flame luminescence-based speed field measurement system and method |
| CN114110664B (en) * | 2021-10-29 | 2023-01-06 | 南京航空航天大学 | Plasma synthetic jet combustion chamber |
| CN114183280A (en) * | 2021-12-13 | 2022-03-15 | 哈尔滨工业大学 | Method for regulating combustion heat release distribution by plasma |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10260709B3 (en) * | 2002-12-23 | 2004-08-12 | Siemens Ag | Method and device for influencing combustion processes in fuels |
| ITTO20120108A1 (en) * | 2012-02-09 | 2013-08-10 | Alenia Aermacchi Spa | ELEMENT FOR SOUND ABSORPTION, IN PARTICULAR INTENDED TO BE MOUNTED ON AIRCRAFT COMPONENTS, SUCH AS ENGINE GONDOLAS. |
| EP3062019B1 (en) * | 2015-02-27 | 2018-11-21 | Ansaldo Energia Switzerland AG | Method and device for flame stabilization in a burner system of a stationary combustion engine |
| CN107420199B (en) * | 2017-03-31 | 2019-08-06 | 中国人民解放军空军工程大学 | The combustion-supporting driver of aeroengine combustor buring room rotational slide arc plasma |
| CN107917337B (en) * | 2017-11-14 | 2019-07-30 | 上海交通大学 | Liquid helium vessel thermal acoustic oscillation based on capacity damping air reservoir inhibits device |
| CN108412616B (en) * | 2018-03-01 | 2019-07-23 | 中国人民解放军空军工程大学 | Aeroengine combustor buring room guide vane formula DBD Plasma Assisted Combustion driver |
| CN108414231A (en) * | 2018-06-07 | 2018-08-17 | 湖南云顶智能科技有限公司 | Modular trial device for swirl flow combustion thermal acoustic oscillation characteristic research |
-
2018
- 2018-12-29 CN CN201811639692.9A patent/CN109724107B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109724107A (en) | 2019-05-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109724107B (en) | Method for suppressing combustion pressure pulsation by high-frequency excitation discharge side plasma | |
| JP4731591B2 (en) | Ignition system and method for generating and sustaining a corona discharge for igniting a combustible gas mixture | |
| EP2844919B1 (en) | Electrical control of combustion | |
| CN109462928B (en) | Method for cooperatively inhibiting combustion pressure pulsation by high-frequency excitation discharge central plasma and side plasma | |
| US20140212820A1 (en) | Burner system including at least one coanda surface and electrodynamic control system, and related methods | |
| CN108566718A (en) | A kind of high frequency plasma excitation device for flowing control | |
| US20100300335A1 (en) | AC Plasma Ejection Gun, the Method for Supplying Power to it and Pulverized Coal Burner | |
| CN111043623A (en) | Method for preventing combustion chamber from generating resonance based on closed-loop negative feedback regulation of electric field influencing flame root | |
| CN105275710A (en) | Active-control resonant ignition system | |
| JP2016130512A (en) | Ignition method and ignition system | |
| CN109729634B (en) | Method for inhibiting combustion pressure pulsation by high-frequency excitation discharge center plasma | |
| JPWO2014084341A1 (en) | Plasma generator | |
| Yu et al. | Scale-up experiments on liquid-fueled active combustion control | |
| JPH09269107A (en) | Apparatus and method for combustion vibration suppression | |
| Akhmadullin et al. | Combustion instability control in the model of combustion chamber | |
| CN115604900A (en) | Method for cooperatively inhibiting combustion oscillation by central plasma and lateral plasma of sliding arc discharge | |
| KR101748739B1 (en) | Atmospheric pressure plasma device with surface dielectric barrier discharge with gas flow guide | |
| Erickson et al. | An active control mechanism to enhance and parametrically study a multi-fuel, Rijke-type pulse combustor | |
| Park et al. | Optimizing Combustion Instability Suppression Using Secondary Fuel Injection | |
| CN113286763B (en) | Method and system for plasma treatment of liquids in continuous flow | |
| RU2336461C1 (en) | Vibration injector | |
| CA2778722A1 (en) | Flow control of combustible mixture into combustion chamber | |
| CN113757719B (en) | Combustion oscillation control method for combustion chamber and combustion chamber | |
| JP6834574B2 (en) | Ignition device | |
| Guyot et al. | Active control of combustion instability using fuel flow modulation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |