A rotating detonation engine based on non-equilibrium plasma initiation and gas supply

Abstract

The present invention provides a rotary detonation engine based on non-equilibrium plasma detonation and gas supply, including a nozzle, a pre-detonation tube and an engine body; a combustion chamber is formed between a combustion chamber outer ring and a combustion chamber inner ring, the pre-detonation tube is installed on the combustion chamber outer ring, and one end of the pre-detonation tube is connected to the combustion chamber; a nozzle is installed at the inlet of the pre-detonation tube; a spark plug is arranged in the pre-detonation tube; a plurality of the nozzles are installed in the combustion chamber, and a plurality of the nozzles are located between the connection between one end of the pre-detonation tube and the combustion chamber and the engine cover plate; a fuel flow channel and an oxidant flow channel that are not connected to each other are arranged in the nozzle; an electrode is arranged in the wall of the fuel flow channel, and a voltage is applied on both sides of the electrode to generate non-equilibrium plasma by ionizing the fuel medium in the flow channel. The present invention can strengthen the combustion process, promote the fuel to burn out, reduce the heat loss of chemical incomplete combustion, and reduce the emission of pollutant gases.

Description

Technical Field

[0001] The invention relates to the field of rotating detonation engines, and in particular to a rotating detonation engine based on non-equilibrium plasma technology for detonation and gas supply. Background Art

[0002] The rotating detonation engine is a new concept propulsion system based on detonation combustion. Compared with conventional gas turbines or ramjet engines, the rotating detonation engine has the advantages of high thermal efficiency, simple structure, low maintenance cost, and high operating frequency. It is one of the ideal power sources for future advanced propulsion systems. Countries around the world are conducting research on rotating detonation engines, and the manpower and material resources invested are increasing dramatically.

[0003] At present, the experimental research of rotating detonation engines is mainly based on gaseous hydrocarbon fuels, but gaseous fuels usually have high storage requirements and low volume energy density. Liquid hydrocarbon fuels are easy to store and transport, and have a higher volume energy density, making them more suitable as engine fuel. In rotating detonation engines, in order to prevent the occurrence of backfire, the fuel and oxidizer are usually injected separately. When the fuel is in liquid form, the fuel and oxidizer are mixed more unevenly, which is not conducive to the stable operation of the rotating detonation engine. Before the fuel and oxidizer burn, the liquid fuel must also undergo atomization and evaporation process, which is not conducive to the rapid mixing of the fuel and oxidizer, resulting in incomplete combustion, which in turn affects the performance of the rotating detonation engine. In addition, for liquid hydrocarbon fuels, it is difficult to trigger a detonation wave in a short period of time using traditional spark plugs. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a rotary detonation engine based on non-equilibrium plasma technology for detonation and gas supply. The detonation device is a pre-detonation tube. In the pre-detonation tube, a stably propagating detonation wave is first formed in the form of a transition from slow combustion to detonation. Then the detonation wave enters the combustion chamber of the rotary detonation engine from the pre-detonation tube to detonate the fuel and oxidant mixture in the combustion chamber. The nozzle contains a plasma generator. The fuel is ionized before entering the engine combustion chamber for mixing, so that the macromolecules in the fuel become small molecules, which changes the chemical balance of the combustion system, promotes the mixing of gas, and then accelerates the flame propagation, further improving the combustion efficiency. At the same time, this method can strengthen the combustion process, promote the fuel to burn out, reduce the heat loss of chemical incomplete combustion, and reduce the emission of pollutant gases.

[0005] The present invention achieves the above technical objectives through the following technical means.

[0006] A rotating detonation engine based on non-equilibrium plasma detonation and gas supply, comprising a nozzle, a pre-detonation tube and an engine body;

[0007] The engine body comprises an outer ring of the combustion chamber, an inner ring of the combustion chamber, a central cone and an engine cover plate; a combustion chamber is formed between the outer ring of the combustion chamber and the inner ring of the combustion chamber, an engine cover plate is arranged at one end of the combustion chamber, and an outlet is arranged at the other end of the combustion chamber; the central cone is coaxially connected with the inner ring of the combustion chamber;

[0008] The pre-detonation tube is installed on the outer ring of the combustion chamber, and one end of the pre-detonation tube is connected to the combustion chamber; a nozzle is installed at the inlet of the pre-detonation tube; a spark plug is arranged in the pre-detonation tube; a plurality of nozzles are installed in the combustion chamber, and a plurality of nozzles are located between the connection between one end of the pre-detonation tube and the combustion chamber and the engine cover plate; a fuel flow channel and an oxidant flow channel that are not connected to each other are arranged in the nozzle; electrodes are arranged in the wall of the fuel flow channel, voltage is applied on both sides of the electrode, and the fuel medium in the flow channel is ionized to generate non-equilibrium plasma.

[0009] Furthermore, the nozzle includes a fuel flow channel, an oxidant flow channel, a high-voltage electrode and a grounding electrode; the fuel flow channel is coaxially arranged with the oxidant flow channel; one end of the fuel flow channel arranged in an outer ring is a fuel inlet; one end of the oxidant flow channel arranged in an inner ring is an oxidant inlet; the wall surface of the fuel flow channel is respectively provided with a high-voltage electrode and a grounding electrode to form a discharge chamber; the high-voltage electrode and the grounding electrode are respectively connected to an AC power supply.

[0010] Furthermore, a first insulating shell is provided on the inner wall of the fuel flow channel, and a second insulating shell is provided on the outer wall of the oxidant flow channel. The annular high-voltage electrode is installed in the first insulating shell, and an annular grounding electrode is installed in the second insulating shell.

[0011] Furthermore, the fuel flow channel outlet and the oxidant flow channel outlet both taper along the flow direction.

[0012] Furthermore, the pre-detonation tube includes a gas detector, a pre-detonation chamber and a spiral obstacle; one end of the pre-detonation chamber is connected to the combustion chamber, a spark plug is installed at the other end of the pre-detonation chamber, a spiral obstacle is arranged in the pre-detonation chamber, and a gas detector is arranged in the pre-detonation chamber for detecting the concentration of the combustible mixture in one end of the pre-detonation chamber connected to the combustion chamber.

[0013] Furthermore, the spiral obstacle blocking ratio is 0.4-0.5.

[0014] Furthermore, one end of the pre-detonation tube is vertically installed outside the outer ring of the engine combustion chamber, and the pre-detonation chamber is parallel to the outer ring of the engine combustion chamber.

[0015] Furthermore, the pre-explosion pipe is provided with a step which gradually contracts along the flow direction.

[0016] Furthermore, the fuel flow channel and the oxidant flow channel are distributed in a ring shape with equal intervals; the first insulating shell, the second insulating shell, the high-voltage electrode and the grounding electrode are coaxially installed; and the inlets of the fuel flow channel and the oxidant flow channel are respectively provided with solenoid valves.

[0017] Furthermore, the first insulating shell and the second insulating shell are made of ceramic material.

[0018] The beneficial effects of the present invention are:

[0019] 1. The rotary detonation engine based on non-equilibrium plasma technology for detonation and gas supply of the present invention controls the intake time and the ignition time of the spark plug through the solenoid valve, thereby accurately controlling the ignition time of the engine. At the same time, the ignition intensity of the engine can be controlled by controlling the intake flow rate. The pre-detonation tube is installed horizontally, which can reduce the size of the engine.

[0020] 2. The rotating detonation engine based on non-equilibrium plasma technology for detonation and gas supply described in the present invention obtains non-equilibrium plasma by applying alternating current of a certain frequency and voltage between two electrodes, thereby making combustion more complete, improving combustion efficiency, and reducing harmful gas emissions caused by incomplete combustion.

[0021] 3. The rotary detonation engine based on non-equilibrium plasma technology for detonation and gas supply described in the present invention can effectively shorten the distance and time for the transition from slow combustion to detonation by installing a spiral obstacle in the pre-detonation chamber, thereby shortening the length of the pre-detonation tube and reducing the weight of the engine.

[0022] 4. The rotary detonation engine based on non-equilibrium plasma technology for detonation and gas supply described in the present invention strengthens detonation combustion through the tapered rear half of the pre-detonation chamber channel.

[0023] 5. The rotating detonation engine based on non-equilibrium plasma technology for detonation and gas supply described in the present invention can improve engine performance by installing a center cone at the tail of the engine.

[0024] 6. The rotating detonation engine based on non-equilibrium plasma technology for detonation and gas supply described in the present invention promotes the mixing of fuel and oxidant through the tapered fuel chamber and oxidant chamber outlet channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. The drawings described below are some embodiments of the present invention. For ordinary technicians in this field, it is obvious that other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic diagram of the structure of the rotating detonation engine for detonation and gas supply based on non-equilibrium plasma technology according to the present invention.

[0027] Figure 2 for Figure 1 AA section view.

[0028] Figure 3 for Figure 2 Magnified view of the nozzle.

[0029] Figure 4 for Figure 1 BB cross-sectional view.

[0030] In the figure:

[0031] 1-combustion chamber outer ring; 2-fuel inlet; 3-engine cover; 4-oxidizer inlet; 5-combustion chamber inner ring; 6-center cone; 7-first nozzle; 8-pre-detonation tube; 9-combustion chamber; 10-solenoid valve; 11-second nozzle; 12-first insulating shell; 13-high-voltage electrode; 14-second insulating shell; 15-ground electrode; 16-fuel flow channel; 17-oxidizer flow channel; 18-gas detector; 19-pre-detonation chamber; 20-spiral obstacle; 21-spark plug. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "axial", "radial", "vertical", "horizontal", "inner", "outer" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0035] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] like Figure 1 and Figure 2 As shown, the rotary detonation engine based on non-equilibrium plasma detonation and gas supply of the present invention comprises a nozzle, a pre-detonation tube 8 and an engine body;

[0037] The engine body comprises an outer ring 1 for combustion chamber, an inner ring 5 for combustion chamber, a central cone 6 and an engine cover plate 3; a combustion chamber 9 is formed between the outer ring 1 for combustion chamber and the inner ring 5 for combustion chamber, an engine cover plate 3 is arranged at one end of the combustion chamber 9, and an outlet is arranged at the other end of the combustion chamber 9; the central cone 6 is coaxially connected with the inner ring 5 for combustion chamber;

[0038] The pre-detonation tube 8 is installed on the combustion chamber outer ring 1, and one end of the pre-detonation tube 8 is connected to the combustion chamber 9; a first nozzle 7 is installed at the inlet of the pre-detonation tube 8; a spark plug 21 is arranged in the pre-detonation tube 8; a plurality of second nozzles 11 are evenly distributed in the combustion chamber 9, and a plurality of the second nozzles 11 are located between the connection between one end of the pre-detonation tube 8 and the combustion chamber 9 and the engine cover 3; a fuel flow channel 16 and an oxidant flow channel 17 that are not connected to each other are arranged in the nozzle; an electrode is arranged in the wall of the fuel flow channel, and a voltage is applied on both sides of the electrode to generate a non-equilibrium plasma by ionizing the fuel medium in the flow channel.

[0039] The first nozzle 7 and the second nozzle 11 have the same structure. Taking the second nozzle 11 as an example, Figure 3 As shown. The second nozzle 11 includes a fuel flow channel 16, an oxidant flow channel 17, a high-voltage electrode 13 and a ground electrode 15; the fuel flow channel 16 is coaxially arranged with the oxidant flow channel 17; the fuel flow channel 16 and the oxidant flow channel 17 are distributed in an annular shape with equal spacing; the first insulating shell 12, the second insulating shell 14, the high-voltage electrode 13 and the ground electrode 15 are coaxially installed; the inlets of the fuel flow channel 16 and the oxidant flow channel 17 are respectively provided with solenoid valves 10. One end of the fuel flow channel 16 arranged in an outer ring is a fuel inlet 2; one end of the oxidant flow channel 17 arranged in an inner ring is an oxidant inlet 4; the oxidant inlet 4 is located on the engine cover plate 3 and is distributed in an annular shape with equal spacing; the fuel inlet 2 is located on the outer wall surface of the outer ring 1 of the combustion chamber and the inner wall surface of the inner ring 5 of the combustion chamber, and is distributed in an annular shape with equal spacing. The wall surface of the fuel flow channel 16 is respectively provided with a high-voltage electrode 13 and a ground electrode 15 to form a discharge chamber; the high-voltage electrode 13 and the ground electrode 15 are respectively connected to an AC power supply. The inner wall of the fuel flow channel 16 is provided with a first insulating shell 12, and the outer wall of the oxidant flow channel 17 is provided with a second insulating shell 14. The annular high-voltage electrode 13 is installed in the first insulating shell 12, and the annular grounding electrode 15 is installed in the second insulating shell 14. The outlet of the fuel flow channel 16 and the outlet of the oxidant flow channel 17 are both gradually contracted along the flow direction. The materials of the first insulating shell 12 and the second insulating shell 14 are ceramic materials. The working principle of the second nozzle 11 is: the combustible gas enters the fuel flow channel 16 through the two fuel inlets 2, and the oxidant enters the oxidant flow channel 17 through the oxidant inlet 4. When a high-voltage AC voltage is applied to the annular high-voltage electrode 13 and the grounding electrode 15, the fuel in the fuel flow channel 16 is ionized to form a non-equilibrium plasma. The outlet of the fuel flow channel 16 and the outlet of the oxidant flow channel 17 are both gradually contracted along the flow direction, which promotes the mixing of the fuel and the oxidant.

[0040] like Figure 4 As shown, the pre-detonation tube 8 includes a gas detector 18, a pre-detonation chamber 19 and a spiral obstacle 20; one end of the pre-detonation chamber 19 is connected to the combustion chamber 9, and a spark plug 21 is installed at the other end of the pre-detonation chamber 19. A spiral obstacle 20 is arranged in the pre-detonation chamber 19, and a gas detector 18 is arranged in the pre-detonation chamber 19 for detecting the concentration of the combustible mixture in one end of the pre-detonation chamber 19 connected to the combustion chamber 9. The blocking ratio of the spiral obstacle 20 is 0.4-0.5. One end of the pre-detonation tube 8 is vertically installed outside the outer ring 1 of the engine combustion chamber, and the pre-detonation chamber 19 is parallel to the outer ring 1 of the engine combustion chamber. The pre-detonation tube 8 is provided with a step that gradually shrinks along the flow direction, and the detonation combustion is enhanced by shrinking the second half of the channel of the pre-detonation chamber 19.

[0041] Working process: First, the fuel and oxidant enter the engine combustion chamber 9 and the pre-detonation chamber 19 through the first nozzle 7 and the second nozzle 11 respectively. When the gas detector 18 detects the combustible mixture at the tail of the pre-detonation chamber 19, the solenoid valve 10 on the first nozzle 7 is closed and the spark plug 21 is turned on. The spiral obstacle 20 enhances the turbulence of the flame and shortens the time and distance for the transition from slow combustion to detonation. When the detonation wave passes through the contraction channel of the pre-detonation chamber 19, the detonation wave is strengthened. Then the detonation wave enters the engine combustion chamber 9, detonates the combustible mixture in the combustion chamber 9, and finally forms a rotating detonation wave in the combustion chamber 9.

[0042] It should be understood that although this specification is described according to various embodiments, not every embodiment contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0043] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the scope of protection of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A rotating detonation engine based on non-equilibrium plasma detonation and gas supply, characterized in that: It includes a nozzle, a pre-explosion tube (8) and an engine body; The engine body comprises a combustion chamber outer ring (1), a combustion chamber inner ring (5), a central cone (6) and an engine cover plate (3); a combustion chamber (9) is formed between the combustion chamber outer ring (1) and the combustion chamber inner ring (5); an engine cover plate (3) is provided at one end of the combustion chamber (9), and an outlet is provided at the other end of the combustion chamber (9); the central cone (6) is coaxially connected to the combustion chamber inner ring (5); The pre-detonation tube (8) is mounted on the combustion chamber outer ring (1), and one end of the pre-detonation tube (8) is connected to the combustion chamber (9); a nozzle is mounted at the inlet of the pre-detonation tube (8); a spark plug (21) is arranged in the pre-detonation tube (8); a plurality of nozzles are mounted in the combustion chamber (9), and a plurality of nozzles are located between the connection between one end of the pre-detonation tube (8) and the combustion chamber (9) and the engine cover plate (3); a fuel flow channel (16) and an oxidant flow channel (17) which are not connected to each other are arranged in the nozzle; an electrode is arranged in the wall of the fuel flow channel, and a voltage is applied to both sides of the electrode to ionize the fuel medium in the flow channel, thereby generating a non-equilibrium plasma.

2. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 1, characterized in that: The nozzle comprises a fuel flow channel (16), an oxidant flow channel (17), a high-voltage electrode (13) and a grounding electrode (15); the fuel flow channel (16) and the oxidant flow channel (17) are coaxially arranged; one end of the fuel flow channel (16) arranged in an outer ring is a fuel inlet (2); one end of the oxidant flow channel (17) arranged in an inner ring is an oxidant inlet (4); the wall surface of the fuel flow channel (16) is respectively provided with a high-voltage electrode (13) and a grounding electrode (15) to form a discharge cavity; the high-voltage electrode (13) and the grounding electrode (15) are respectively connected to an AC power source.

3. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 2, characterized in that: The inner wall surface of the fuel flow channel (16) is provided with a first insulating shell (12), and the outer wall surface of the oxidant flow channel (17) is provided with a second insulating shell (14). The first insulating shell (12) has an annular high-voltage electrode (13) installed in it, and the second insulating shell (14) has an annular grounding electrode (15) installed in it.

4. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 2, characterized in that: The outlet of the fuel flow channel (16) and the outlet of the oxidant flow channel (17) both gradually contract along the flow direction.

5. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 1, characterized in that: The pre-detonation tube (8) comprises a gas detector (18), a pre-detonation chamber (19) and a spiral obstacle (20); one end of the pre-detonation chamber (19) is connected to the combustion chamber (9), a spark plug (21) is installed at the other end of the pre-detonation chamber (19), the spiral obstacle (20) is arranged in the pre-detonation chamber (19), and the pre-detonation chamber (19) is provided with a gas detector (18) for detecting the concentration of a combustible mixture in one end of the pre-detonation chamber (19) connected to the combustion chamber (9).

6. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 5, characterized in that: The blocking ratio of the spiral obstacle (20) is 0.4-0.

5.

7. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 5, characterized in that: One end of the pre-detonation tube (8) is vertically mounted outside the outer ring (1) of the engine combustion chamber, and the pre-detonation chamber (19) is parallel to the outer ring (1) of the engine combustion chamber.

8. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 5, characterized in that: The pre-explosion pipe (8) is provided with a step which gradually contracts along the flow direction.

9. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 3, characterized in that: The fuel flow channel (16) and the oxidant flow channel (17) are distributed in an annular shape at equal intervals; the first insulating shell (12), the second insulating shell (14), the high-voltage electrode (13) and the grounding electrode (15) are coaxially installed; and electromagnetic valves (10) are respectively provided at the inlets of the fuel flow channel (16) and the oxidant flow channel (17).

10. The rotating detonation engine based on non-equilibrium plasma detonation and gas supply according to claim 3, characterized in that: The first insulating shell (12) and the second insulating shell (14) are made of ceramic material.

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