Double-path sliding arc ignition head based on multi-point atomization, strong rotational flow, bluff body backflow flame stabilization and liquid ammonia cooling electrode and operation method of double-path sliding arc ignition head

Abstract

The invention discloses a double-path sliding arc ignition head based on multi-point atomization, strong rotational flow and bluff body backflow flame stabilization and a liquid ammonia cooling electrode and an operation method of the double-path sliding arc ignition head. A first sliding arc is arranged in a first pre-combustion stage and mixed with atomized ammonia to form flame, and meanwhile, under the action of a bluff body and a strong rotational flow backflow area, atomization and combustion of the ammonia in the first pre-combustion stage are promoted; a second sliding arc is arranged in a second pre-combustion stage, atomized ammonia is mixed with air, flame is formed through discharging of the sliding arc, and the atomized ammonia is ignited to form second pre-combustion stage flame; under the action of the first pre-combustion stage flame and the second pre-combustion stage flame, stable main combustion stage flame is formed; the electrode is cooled by latent heat of liquid ammonia gasification, the ablation rate of the electrode is reduced, the discharge power is improved, and the gliding arc ignition capability is greatly improved. The defects that a high-power sliding arc electrode is high in ablation speed, short in service life and the like are overcome, liquid ammonia is ignited through a double-path high-power sliding arc, pre-combustion-stage and main-combustion-stage flames are formed, and the problems that ammonia ignition is difficult, combustion is unstable and the like are effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of high-end equipment, and in particular to a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrodes, and an operation method thereof, which is used for developing a new type of zero-carbon burner. Background Art

[0002] Climate change is one of the main threats to the earth's environment, and the carbon dioxide emitted into the atmosphere from fossil energy sources exacerbates global warming. Currently, the electricity and heat production industry accounts for the highest share of carbon emissions in the country.

[0003] In order to reduce carbon emissions from fossil energy, it is necessary to vigorously develop green new energy, including photovoltaics, wind power, etc. Due to the strong random volatility of wind and solar energy, the low utilization rate of new energy, resulting in waste of resources, so energy storage technology is needed to smooth the peak and fill the valley. Hydrogen energy, as a kind of energy storage technology, has the advantages of being green, efficient, carbon-free, and having a long storage time. It is an important part of the future energy system and will help accelerate the green and low-carbon transformation of high-energy-consuming and high-carbon emission industries. However, the large-scale application of hydrogen energy urgently needs to break through low-cost and high-efficiency fuel cell technology and low-cost and safe hydrogen storage and transportation technology. Among them, the poor safety and high cost of hydrogen storage and transportation have become the main difficulties in the development of hydrogen energy.

[0004] As a hydrogen carrier, ammonia has the characteristics of high energy density, low storage and transportation cost, and high safety, and is expected to break through the bottleneck of hydrogen energy development. However, in the application of ammonia fuel, there are problems such as low flame propagation speed, ignition difficulty, poor flame stability, and high NOx emissions, which need to be solved urgently.

[0005] Scholars in this field have conducted in-depth research on the problems of difficult ammonia ignition and poor flame stability, including technologies such as adding fossil fuels to ammonia, adding ammonia to hydrogen, oxygen-enriched combustion, plasma-assisted combustion and staged combustion technology. Among them, adding fossil fuels to ammonia can effectively increase the flame propagation speed of the fuel, but it cannot completely solve the carbon emission problem; ammonia blended with hydrogen combustion can increase the flame propagation speed without additional carbon emissions, but the storage and transportation of hydrogen or online cracking of ammonia to produce hydrogen technology needs further research; oxygen-enriched combustion technology has low difficulty and high cost, which greatly reduces the economy of ammonia combustion and loses its competitive advantage. Plasma can enhance combustion through thermal, chemical and transport effects, effectively reduce ignition delay time and increase flame propagation speed. The patent "A sliding arc plasma duty flame head in an aircraft engine combustion chamber" is a Chinese patent application with application number CN202111216787.1. Its fuel nozzle is located in the cathode sleeve, and sliding arc discharge is generated at the outlet of the swirler, which improves the quality of the outlet temperature field and increases the service life of the aircraft engine turbine; the patent "A three-dimensional rotating sliding arc plasma exciter combined with a single and double path" is a Chinese patent application with application number CN202110298162.8. The inner and outer groups of swirlers correspond to a group of electrodes respectively, which can generate two sliding arcs at the same time, broaden the ignition boundary of the aircraft engine combustion chamber, and improve combustion efficiency; the patent "A variable sliding arc plasma central graded combustion chamber head" is a Chinese patent application with application number CN202310426844.1. Electrodes are arranged in the main combustion stage and the duty stage respectively to generate two sliding arcs, and the swirler can be disassembled and replaced, which has the advantages of simple structure, high reliability and low cost. The above-mentioned sliding arc plasma actuators are all used for the ignition of kerosene in aircraft engines. Due to their low discharge power and heat release power, they cannot meet the stable combustion of ammonia at high flow rates, and are prone to ammonia escape problems caused by incomplete combustion. In particular, when liquid ammonia is introduced into high-power burners as fuel, higher requirements are placed on the ignition performance of the igniter.

[0006] However, directly increasing the discharge power of the sliding arc igniter will cause the electrode surface temperature to be too high, accelerate the electrode surface ablation, and seriously affect the igniter life.

[0007] In response to the above-mentioned problem of difficult ignition of ammonia burners under high power and high flow rate, the present invention proposes a dual-path sliding arc ignition head solution based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, which can effectively solve the problems of difficult ignition of ammonia under high flow rate, unstable and insufficient combustion, etc. Summary of the invention

[0008] The purpose of the present invention is to provide a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrodes to achieve reliable ignition and stable combustion of ammonia in the burner.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] A dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, comprising a first high-voltage electrode, a first air inlet, a first swirler, a low-voltage electrode, a second air inlet, a second swirler, a second high-voltage electrode, a third air inlet, a third swirler, an ignition head shell, a plasma igniter, a strong reflux zone, a first sliding arc, a second sliding arc, a first pre-combustion stage flame, a second pre-combustion stage flame, and a main combustion stage flame; the first high-voltage electrode comprises a first ammonia inlet and a first ammonia injection port, the first high-voltage electrode is located at the front end center of the ignition head, maintains an air passage with the low-voltage electrode, and a first swirler is arranged in the passage; the first air inlet is arranged between the first high-voltage electrode and the low-voltage electrode In the ventilation channel between the electrodes; the low-voltage electrode includes a second ammonia injection port, a third ammonia injection port, and a fourth ammonia injection port; the second high-voltage electrode and the low-voltage electrode maintain a ventilation channel, and a second cyclone is arranged in the channel; the second air inlet is arranged in the ventilation channel between the second high-voltage electrode and the low-voltage electrode; the second high-voltage electrode includes a third ammonia inlet and a fifth ammonia injection port; the ignition head shell and the second high-voltage electrode maintain a ventilation channel, and a third cyclone is arranged in the channel; the third air inlet is arranged in the ventilation channel between the second high-voltage electrode and the ignition head shell; the first high-voltage electrode and the second high-voltage electrode are respectively connected to the high-voltage ends of the two power supplies; the low-voltage electrode is connected to the low-voltage ends of the two power supplies;

[0011] The first high-voltage electrode, the first cyclone, the low-voltage electrode, the second cyclone, the second high-voltage electrode, the third cyclone, and the ignition head housing are all coaxial;

[0012] Furthermore, the outer contour of the first high-voltage electrode is an axisymmetric structure, and its radius gradually increases along the axial direction, and then gradually decreases, so that the ventilation channel between the first high-voltage electrode and the low-voltage electrode changes from large to small, and then gradually increases; the first high-voltage electrode is provided with N on the side close to the first pre-combustion stage flame 1 (2≤N 1 ≤15) first ammonia injection ports; a first ammonia inlet is provided in the first high-voltage electrode; the first sliding arc is generated in the ventilation channel between the first high-voltage electrode and the low-voltage electrode, and moves under the action of the airflow; a plasma igniter is provided at the center of the end face of the first high-voltage electrode (1) close to the downstream;

[0013] Further, the low-voltage electrode includes a second ammonia inlet, a second ammonia injection port, a third ammonia injection port, and a fourth ammonia injection port; the second ammonia injection port is located on one side of the first sliding arc and at the end of the first sliding arc discharge zone; the third ammonia injection port is located on the side close to the second high-voltage electrode and upstream of the second sliding arc discharge zone; the fourth ammonia injection port is located on the end face of the low-voltage electrode close to the downstream; the second ammonia injection port, the third ammonia injection port, and the fourth ammonia injection port are distributed N along the circumferential direction 2 (3≤N 2 ≤25); liquid ammonia is introduced from the second ammonia inlet and ejected from the second ammonia ejection port, the third ammonia ejection port and the fourth ammonia ejection port; the liquid ammonia flow rate ejected from the fourth ammonia ejection port is higher than the liquid ammonia flow rate ejected from the second ammonia ejection port; the liquid ammonia flow rate ejected from the second ammonia ejection port is higher than the liquid ammonia flow rate ejected from the third ammonia ejection port; the low-voltage electrode is insulated from the first high-voltage electrode by the first cyclone;

[0014] Furthermore, the second high-voltage electrode includes a third ammonia inlet and a fifth ammonia injection port; the fifth ammonia injection port is located near the side of the ignition head shell; liquid ammonia is introduced from the third ammonia inlet and sprayed out from the fifth ammonia injection port; the fifth ammonia injection port is distributed N along the circumferential direction 3 (3≤N 3 ≤30); the second sliding arc is generated in the ventilation channel between the second high-voltage electrode and the low-voltage electrode, and moves under the action of the airflow; the second high-voltage electrode is insulated from the low-voltage electrode by the second cyclone; the ignition head shell is insulated from the second high-voltage electrode by the third cyclone.

[0015] Furthermore, the ignition head adopts strong swirl and blunt body reflux flame stabilization, dual-path sliding arc combustion assistance and liquid ammonia cooling electrode means; the strong swirl and blunt body reflux flame stabilization means include the following steps: the gas introduced from the first air inlet generates a strong swirl flow field after passing through the first cyclone, and generates a reflux zone in the center. Under the action of the blunt body structure of the first high-voltage electrode, a reflux zone is also generated. The two reflux zones overlap to form a strong reflux zone. The strong reflux zone sucks the flame back to the plasma igniter, mixes with the high temperature generated by the discharge of the plasma igniter, and then mixes with the liquid ammonia injected from the first ammonia injection port and the second ammonia injection port respectively, so as to promote the atomization of the liquid ammonia and enhance the combustion;

[0016] Furthermore, the dual-path sliding arc combustion-supporting means comprises the following steps: the first sliding arc is elongated under the action of the airflow, and is respectively mixed with the liquid ammonia sprayed from the first ammonia spray port and the second ammonia spray port, so as to promote the atomization and intensified combustion of the liquid ammonia, and form a first pre-combustion stage flame, and the first pre-combustion stage flame is mixed with the liquid ammonia sprayed from the fourth ammonia spray port, so as to promote the atomization and combustion of the liquid ammonia; the ammonia introduced from the third ammonia spray port is mixed with the air introduced from the second air inlet, and then a flame is generated after the second sliding arc discharge, and the flame promotes the gasification and combustion of the liquid ammonia from the fourth ammonia spray port, so as to form a second pre-combustion stage flame;

[0017] Furthermore, the liquid ammonia cooling electrode means comprises the following steps: liquid ammonia is introduced from the first ammonia inlet, the second ammonia inlet and the third ammonia inlet respectively, and after the liquid ammonia is gasified, it absorbs the heat from the surfaces of the first high-voltage electrode, the low-voltage electrode and the second high-voltage electrode respectively, thereby lowering the electrode temperature and reducing the electrode ablation rate;

[0018] Further, the ignition head has three working modes. In working mode one, liquid ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet, the second ammonia inlet and the third ammonia inlet respectively, and the first sliding arc and the second sliding arc are both released to maximum power; in working mode two, gaseous ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet, the second ammonia inlet and the third ammonia inlet respectively, and the first sliding arc operates at a relatively low power, and the second sliding arc is released to the maximum power; in working mode three, gaseous ammonia, gaseous ammonia and liquid ammonia are introduced into the first ammonia inlet, the second ammonia inlet and the third ammonia inlet respectively, and the first sliding arc and the second sliding arc operate at a relatively low power; the three working modes of the ignition head have the maximum operating powers from large to small, namely working mode one, working mode two and working mode three;

[0019] Furthermore, the operation method of the ignition head is as follows:

[0020] 1) Open the first air inlet, the second air inlet, and the third air inlet, and let in air, air, and air respectively, and reach the set flow rate respectively;

[0021] 2) Turn on the power of the plasma igniter, the first sliding arc, and the second sliding arc to reach the set power;

[0022] 3) Open the first ammonia inlet and the second ammonia inlet, and introduce gaseous ammonia or liquid ammonia respectively according to the working mode, and reach the set flow rate respectively;

[0023] 4) After the stable first pre-combustion stage flame and second pre-combustion stage flame are formed, the third ammonia inlet is opened, and liquid ammonia is introduced to reach the set flow rate to form the main combustion stage flame.

[0024] The beneficial effects of the present invention are:

[0025] The present invention uses the latent heat of liquid ammonia gasification to reduce the electrode temperature, improve the life and power of the sliding arc, and thus greatly improve the ignition performance of the sliding arc; the present invention realizes the efficient ignition and flame stabilization of large-flow liquid ammonia through strong swirl and blunt body reflux and dual-path high-power sliding arcs: the liquid ammonia is directly ignited through a high-power first sliding arc, and a stable first pre-combustion stage flame is formed through the blunt body and the swirl reflux zone; under the action of the first pre-combustion stage flame and the high-power second sliding arc, the liquid ammonia is ignited to form a stable second pre-combustion stage flame, and then a stable main combustion stage flame is formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrodes;

[0027] In the figure: 1-first high-voltage electrode; 1-1-first ammonia inlet; 1-2-first ammonia injection port; 2-first air inlet; 3-first cyclone; 4-low-voltage electrode; 4-1-second ammonia inlet; 4-2-second ammonia injection port; 4-3-third ammonia injection port; 4-4-fourth ammonia injection port; 5-second air inlet; 6-second cyclone; 7-second high-voltage electrode; 7-1-third ammonia inlet; 7-2-fifth ammonia injection port; 8-third air inlet; 9-third cyclone; 10-ignition head housing; 11-plasma igniter; 12-strong reflux zone; 13-first sliding arc; 14-second sliding arc; 15-first pre-combustion stage flame; 16-second pre-combustion stage flame; 17-main combustion stage flame. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0029] According to one embodiment of the present invention, Figure 1As shown, a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode includes a first high-voltage electrode 1, a first air inlet 2, a first swirler 3, a low-voltage electrode 4, a second air inlet 5, a second swirler 6, a second high-voltage electrode 7, a third air inlet 8, a third swirler 9, an ignition head shell 10, a plasma igniter 11, a strong reflux zone 12, a first sliding arc 13, a second sliding arc 14, a first pre-combustion stage flame 15, a second pre-combustion stage flame 16, and a main combustion stage flame 17; the first high-voltage electrode 1 includes a first ammonia inlet 1-1 and a first ammonia injection port 1-2, the first high-voltage electrode 1 is located at the front end center of the ignition head, maintains a ventilation channel with the low-voltage electrode 4, and a first swirler 3 is arranged in the channel; the first air inlet 2 is arranged between the first high-voltage electrode 1 and The ventilation channel between the low-pressure electrodes 4; the low-pressure electrode 4 includes a second ammonia injection port 4-2, a third ammonia injection port 4-3, and a fourth ammonia injection port 4-4; the second high-pressure electrode 7 maintains a ventilation channel with the low-pressure electrode 4, and a second cyclone 6 is arranged in the channel; the second air inlet 5 is arranged in the ventilation channel between the second high-pressure electrode 7 and the low-pressure electrode 4; the second high-pressure electrode 7 includes a third ammonia inlet 7-1 and a fifth ammonia injection port 7-2; the ignition head shell 10 maintains a ventilation channel with the second high-pressure electrode 7, and a third cyclone 9 is arranged in the channel; the third air inlet 8 is arranged in the ventilation channel between the second high-pressure electrode 7 and the ignition head shell 10; the first high-pressure electrode 1 and the second high-pressure electrode 7 are respectively connected to the high-pressure ends of the two power supplies; the low-pressure electrode 4 is connected to the low-pressure ends of the two power supplies;

[0030] The first high-voltage electrode 1, the first cyclone 3, the low-voltage electrode 4, the second cyclone 6, the second high-voltage electrode 7, the third cyclone 9, and the ignition head housing 10 are all coaxial;

[0031] Furthermore, the outer contour of the first high-voltage electrode 1 is an axisymmetric structure, and its radius gradually increases along the axial direction and then gradually decreases, so that the ventilation channel between the first high-voltage electrode 1 and the low-voltage electrode 4 changes from large to small and then gradually increases; the first high-voltage electrode 1 is provided with 10 first ammonia injection ports 1-2 on the side close to the first pre-combustion stage flame 14; the first high-voltage electrode 1 is provided with a first ammonia inlet 1-1; the first sliding arc 13 is generated in the ventilation channel between the first high-voltage electrode 1 and the low-voltage electrode 4, and moves under the action of the airflow; the first high-voltage electrode 1 is provided with a plasma igniter 11 at the center of the end face close to the downstream;

[0032] Further, the low-voltage electrode 4 includes a second ammonia inlet 4-1, a second ammonia injection port 4-2, a third ammonia injection port 4-3, and a fourth ammonia injection port 4-4; the second ammonia injection port 4-2 is located on one side of the first sliding arc 13 and at the end of the discharge zone of the first sliding arc 13; the third ammonia injection port 4-3 is located on the side close to the second high-voltage electrode 7 and upstream of the discharge zone of the second sliding arc 14; the fourth ammonia injection port 4-4 is located on the end face of the low-voltage electrode 4 close to the downstream; the second ammonia injection port 4-2, the third ammonia injection port 4-3, and the fourth ammonia injection port 4-4 are located on the end face of the low-voltage electrode 4 close to the downstream; There are 15 ammonia injection ports 4-3 and the fourth ammonia injection port 4-4 distributed along the circumferential direction; liquid ammonia is introduced from the second ammonia inlet 4-1 and ejected from the second ammonia injection port 4-2, the third ammonia injection port 4-3 and the fourth ammonia injection port 4-4; the liquid ammonia flow rate ejected from the fourth ammonia injection port 4-4 is higher than the liquid ammonia flow rate ejected from the second ammonia injection port 4-2; the liquid ammonia flow rate ejected from the second ammonia injection port 4-2 is higher than the liquid ammonia flow rate ejected from the third ammonia injection port 4-3; the low-voltage electrode 4 is insulated from the first high-voltage electrode 1 through the first cyclone 3;

[0033] Furthermore, the second high-voltage electrode 7 includes a third ammonia inlet 7-1 and a fifth ammonia injection port 7-2; the fifth ammonia injection port 7-2 is located near the side of the ignition head shell 10; liquid ammonia is introduced from the third ammonia inlet 7-1 and ejected from the fifth ammonia injection port 7-2; 20 fifth ammonia injection ports 7-2 are distributed circumferentially; the second sliding arc 14 is generated in the ventilation channel between the second high-voltage electrode 7 and the low-voltage electrode 4, and moves under the action of airflow; the second high-voltage electrode 7 is insulated from the low-voltage electrode 4 through the second cyclone 6; the ignition head shell 10 is insulated from the second high-voltage electrode 7 through the third cyclone 9.

[0034] Furthermore, the ignition head adopts strong swirl and blunt body reflux flame stabilization, dual-path sliding arc combustion assistance and liquid ammonia cooling electrode means; the strong swirl and blunt body reflux flame stabilization means include the following steps: the gas introduced from the first air inlet 2 generates a strong swirl flow field after passing through the first swirler 3, and generates a reflux zone in the center. Under the action of the blunt body structure of the first high-voltage electrode 1, a reflux zone is also generated. The two reflux zones overlap to form a strong reflux zone 12. The strong reflux zone 12 sucks the flame back to the plasma igniter 11, and after mixing with the high temperature generated by the discharge of the plasma igniter 11, it is mixed with the liquid ammonia injected from the first ammonia injection port 1-2 and the second ammonia injection port 4-2 respectively, so as to promote the atomization of the liquid ammonia and enhance the combustion;

[0035] Furthermore, the dual-path sliding arc combustion-supporting means comprises the following steps: the first sliding arc 13 is elongated under the action of the airflow, and is respectively mixed with the liquid ammonia sprayed from the first ammonia injection port 1-2 and the second ammonia injection port 4-2, so as to promote the atomization and intensified combustion of the liquid ammonia, and form a first pre-combustion stage flame 15; the first pre-combustion stage flame 15 is mixed with the liquid ammonia sprayed from the fourth ammonia injection port 4-4, so as to promote the atomization and combustion of the liquid ammonia; the ammonia introduced from the third ammonia injection port 4-3 is mixed with the air introduced from the second air inlet 5, and then discharged through the second sliding arc 14 to generate a flame, and the flame promotes the gasification and combustion of the liquid ammonia from the fourth ammonia injection port 4-4, so as to form a second pre-combustion stage flame 16;

[0036] Furthermore, the liquid ammonia cooling electrode means comprises the following steps: liquid ammonia is introduced from the first ammonia inlet 1-1, the second ammonia inlet 4-1 and the third ammonia inlet 7-1 respectively, and after the liquid ammonia is gasified, it absorbs the heat from the surfaces of the first high-voltage electrode 1, the low-voltage electrode 4 and the second high-voltage electrode 7 respectively, thereby lowering the electrode temperature and reducing the electrode ablation rate;

[0037] Further, the ignition head has three working modes. In working mode one, liquid ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet 1-1, the second ammonia inlet 4-1 and the third ammonia inlet 7-1 respectively, and the first sliding arc 13 and the second sliding arc 14 are both released to maximum power; in working mode two, gas ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet 1-1, the second ammonia inlet 4-1 and the third ammonia inlet 7-1 respectively, and the first sliding arc 13 operates at a relatively low power, and the second sliding arc 14 is released to the maximum power; in working mode three, gas ammonia, gas ammonia and liquid ammonia are introduced into the first ammonia inlet 1-1, the second ammonia inlet 4-1 and the third ammonia inlet 7-1 respectively, and the first sliding arc 13 and the second sliding arc 14 operate at a relatively low power; the three working modes of the ignition head have the maximum operating powers from large to small, namely working mode one, working mode two and working mode three;

[0038] Furthermore, the operation method of the ignition head is as follows:

[0039] 1) Open the first air inlet 2, the second air inlet 5, and the third air inlet 8, and let in air, air, and air respectively, and reach the set flow rate respectively;

[0040] 2) Turn on the power of the plasma igniter 11, the first sliding arc 13, and the second sliding arc 14 to reach the set power;

[0041] 3) Open the first ammonia inlet 1-1 and the second ammonia inlet 4-1, and introduce liquid ammonia to reach the set flow rate respectively;

[0042] 4) After the stable first pre-combustion stage flame 15 and the second pre-combustion stage flame 16 are formed, the third ammonia inlet 7-1 is opened, and liquid ammonia is introduced to reach a set flow rate to form a main combustion stage flame 17.

Claims

1. A dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized by: The invention comprises a first high-voltage electrode (1), a first air inlet (2), a first cyclone (3), a low-voltage electrode (4), a second air inlet (5), a second cyclone (6), a second high-voltage electrode (7), a third air inlet (8), a third cyclone (9) and an ignition head shell (10); the first high-voltage electrode (1) comprises a first ammonia inlet (1-1) and a first ammonia injection port (1-2); the first high-voltage electrode (1) is located at the front end center of the ignition head and maintains an air passage with the low-voltage electrode (4), and a first cyclone (3) is arranged in the passage; the first air inlet (2) is arranged in the air passage between the first high-voltage electrode (1) and the low-voltage electrode (4); the low-voltage electrode (4) comprises a second ammonia injection port (4-2), a third ammonia injection port (4-3) and a fourth ammonia injection port (4-4); The second high-voltage electrode (7) and the low-voltage electrode (4) maintain a ventilation channel, and a second cyclone (6) is arranged in the channel; the second air inlet (5) is arranged in the ventilation channel between the second high-voltage electrode (7) and the low-voltage electrode (4); the second high-voltage electrode (7) includes a third ammonia inlet (7-1) and a fifth ammonia injection port (7-2); the ignition head shell (10) and the second high-voltage electrode (7) maintain a ventilation channel, and a third cyclone (9) is arranged in the channel; the third air inlet (8) is arranged in the ventilation channel between the second high-voltage electrode (7) and the ignition head shell (10); the first high-voltage electrode (1) and the second high-voltage electrode (7) are respectively connected to the high-voltage ends of two power supplies; the low-voltage electrode (4) is connected to the low-voltage ends of the two power supplies; The first high-voltage electrode (1), the first cyclone (3), the low-voltage electrode (4), the second cyclone (6), the second high-voltage electrode (7), the third cyclone (9), and the ignition head housing (10) are all coaxial.

2. According to claim 1, a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized in that: The outer contour of the first high-voltage electrode (1) is an axisymmetric structure, and its radius gradually increases along the axial direction and then gradually decreases, so that the ventilation channel between the first high-voltage electrode (1) and the low-voltage electrode (4) changes from large to small and then gradually increases; the first high-voltage electrode (1) is provided with N1 (2≤N1≤15) first ammonia injection ports (1-2) on the side close to the first pre-combustion stage flame (15); the first high-voltage electrode (1) is provided with a first ammonia inlet (1-1); the first sliding arc (13) is generated in the ventilation channel between the first high-voltage electrode (1) and the low-voltage electrode (4), and moves under the action of the airflow; the first high-voltage electrode (1) is provided with a plasma igniter (11) at the center of the end face close to the downstream.

3. According to claim 1, a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized in that: The low-voltage electrode (4) comprises a second ammonia inlet (4-1), a second ammonia injection port (4-2), a third ammonia injection port (4-3), and a fourth ammonia injection port (4-4); the second ammonia injection port (4-2) is located on one side of the first sliding arc (13) and at the end of the discharge zone of the first sliding arc (13); the third ammonia injection port (4-3) is located on one side close to the second high-voltage electrode (7) and upstream of the discharge zone of the second sliding arc (14); the fourth ammonia injection port (4-4) is located on the end face of the low-voltage electrode (4) close to the downstream; the second ammonia injection port (4-2) and the third ammonia injection port (4-3) are located on the end face of the low-voltage electrode (4) close to the downstream; , the fourth ammonia injection port (4-4) is distributed in the circumferential direction at N2 (3≤N2≤25); liquid ammonia is introduced from the second ammonia inlet (4-1) and is ejected from the second ammonia injection port (4-2), the third ammonia injection port (4-3) and the fourth ammonia injection port (4-4); the flow rate of liquid ammonia ejected from the fourth ammonia injection port (4-4) is higher than the flow rate of liquid ammonia ejected from the second ammonia injection port (4-2); the flow rate of liquid ammonia ejected from the second ammonia injection port (4-2) is higher than the flow rate of liquid ammonia ejected from the third ammonia injection port (4-3); the low-voltage electrode (4) is insulated from the first high-voltage electrode (1) through the first cyclone (3).

4. According to claim 1, a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized in that: The second high-voltage electrode (7) comprises a third ammonia inlet (7-1) and a fifth ammonia injection port (7-2); the fifth ammonia injection port (7-2) is located near the side of the ignition head shell (10); liquid ammonia is introduced through the third ammonia inlet (7-1) and ejected through the fifth ammonia injection port (7-2); the fifth ammonia injection port (7-2) is distributed N3 (3≤N3≤30) in the circumferential direction; the second sliding arc (14) is generated in the ventilation channel between the second high-voltage electrode (7) and the low-voltage electrode (4), and moves under the action of the airflow; the second high-voltage electrode (7) is insulated from the low-voltage electrode (4) by the second cyclone (6); the ignition head shell (10) is insulated from the second high-voltage electrode (7) by the third cyclone (9).

5. According to claim 1, a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized in that: The ignition head adopts strong swirl and blunt body reflux flame stabilization, dual-path sliding arc combustion assistance and liquid ammonia cooling electrode means; the strong swirl and blunt body reflux flame stabilization means comprises the following steps: the gas introduced from the first air inlet (2) generates a strong swirl flow field after passing through the first swirler (3), generates a reflux zone in the center, and under the action of the blunt body structure of the first high-voltage electrode (1), also generates a reflux zone, the two reflux zones overlap to form a strong reflux zone (12), the strong reflux zone (12) sucks the flame back to the plasma igniter (11), mixes with the high temperature generated by the discharge of the plasma igniter (11), and then mixes with the liquid ammonia sprayed from the first ammonia spray port (1-2) and the second ammonia spray port (4-2), respectively, to promote the atomization of the liquid ammonia and strengthen the combustion; The dual-path sliding arc combustion-supporting means comprises the following steps: the first sliding arc (13) is elongated under the action of the airflow, and is respectively mixed with the liquid ammonia sprayed from the first ammonia spray port (1-2) and the second ammonia spray port (4-2), so as to promote the atomization and intensified combustion of the liquid ammonia, thereby forming a first pre-combustion stage flame (15); the first pre-combustion stage flame (15) is mixed with the liquid ammonia sprayed from the fourth ammonia spray port (4-4), so as to promote the atomization and combustion of the liquid ammonia; the ammonia introduced from the third ammonia spray port (4-3) is mixed with the air introduced from the second air inlet (5), and then discharged through the second sliding arc (14) to generate a flame, and the flame promotes the gasification and combustion of the liquid ammonia from the fourth ammonia spray port (4-4), thereby forming a second pre-combustion stage flame (16); The liquid ammonia electrode cooling method comprises the following steps: liquid ammonia is introduced through a first ammonia inlet (1-1), a second ammonia inlet (4-1) and a third ammonia inlet (7-1), and after the liquid ammonia is vaporized, it absorbs heat from the surfaces of the first high-voltage electrode (1), the low-voltage electrode (4) and the second high-voltage electrode (7), thereby lowering the electrode temperature and reducing the electrode ablation rate.

6. A dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode according to claim 1, characterized in that: The ignition head has three working modes. In working mode 1, liquid ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet (1-1), the second ammonia inlet (4-1) and the third ammonia inlet (7-1) respectively, and the first sliding arc (13) and the second sliding arc (14) are both released to maximum power. In working mode 2, gaseous ammonia, liquid ammonia and liquid ammonia are introduced into the first ammonia inlet (1-1), the second ammonia inlet (4-1) and the third ammonia inlet (7-1) respectively, the first sliding arc (13) operates at a relatively low power, and the second sliding arc (14) is released to a maximum power; In working mode three, gaseous ammonia, gaseous ammonia and liquid ammonia are introduced into the first ammonia inlet (1-1), the second ammonia inlet (4-1) and the third ammonia inlet (7-1) respectively, and the first sliding arc (13) and the second sliding arc (14) are both operated at relatively low power; the three working modes of the ignition head have the following maximum operating powers from large to small, namely working mode one, working mode two and working mode three.

7. An operating method of a dual-path sliding arc ignition head based on multi-point atomization, strong swirl and blunt body reflux flame stabilization, and liquid ammonia cooling electrode, characterized in that: Using the ignition head according to claim 1, the operation method is: 1) Open the first air inlet (2), the second air inlet (5), and the third air inlet (8), and let in air, air, and air respectively, until the set flow rates are reached; 2) Turning on the power of the plasma igniter (11), the first sliding arc (13), and the second sliding arc (14) to reach the set power; 3) Open the first ammonia inlet (1-1) and the second ammonia inlet (4-1), and introduce gaseous ammonia or liquid ammonia respectively according to the working mode, and reach the set flow rate respectively; 4) After a stable first pre-combustion stage flame (15) and a second pre-combustion stage flame (16) are formed, the third ammonia inlet (7-1) is opened, and liquid ammonia is introduced to reach a set flow rate to form a main combustion stage flame (17).

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