CN216591801U

CN216591801U - Micro turbojet engine combustion chamber

Info

Publication number: CN216591801U
Application number: CN202122707228.2U
Authority: CN
Inventors: 马库斯·齐普勒; 张珅; 高宏伟
Original assignee: Suzhou Kaide Aviation Technology Co ltd
Current assignee: Suzhou Kaide Aviation Technology Co ltd
Priority date: 2021-11-05
Filing date: 2021-11-05
Publication date: 2022-05-24
Anticipated expiration: 2031-11-05

Abstract

The utility model relates to a micro turbojet engine combustion chamber, which comprises a combustion chamber shell, wherein a main fuel oil supply capillary, an evaporation pipe and an ignition module are arranged in the combustion chamber shell, the ignition module comprises a high-voltage electric arc igniter and a starting fuel oil ejector, the high-voltage electric arc igniter comprises a discharge anode and a discharge cathode, the discharge anode is a needle electrode, the discharge cathode is in a tip structure and is arranged beside the discharge anode, and the discharge anode discharges to the discharge cathode to generate high-voltage electric arc. The ignition module in the combustion chamber ignites the engine in a mode that the tip discharge of a high-voltage arc igniter is matched with the atomized fuel sprayed by a starting fuel injector, the preheating process is not needed, the ignition time is effectively shortened, the installation angle of the engine is not limited, the engine is enabled to ignite more quickly and easily, and the ignition stability is improved; meanwhile, the point discharge hardly abrades the igniter, so that the service life of the igniter is prolonged, and the overall reliability of the engine is improved.

Description

Micro turbojet engine combustion chamber

Technical Field

The utility model relates to the field of micro turbojet engines, in particular to a combustion chamber of a micro turbojet engine.

Background

The structure of the turbojet engine consists of an air inlet channel, an air compressor, a combustion chamber, a turbine and a tail nozzle, wherein air enters the engine through the air inlet channel, is pressurized through the air compressor and a diffuser, enters the combustion chamber after being pressurized, is heated through the combustion chamber, and flows through the turbine and the tail nozzle to be finally sprayed out from the tail nozzle. Smooth ignition during engine start-up is an important indicator of the overall performance of the engine. In order to realize ignition of the engine, fuel of the engine needs to be ignited through an igniter, the ignited fuel enters a combustion chamber along with continuous compressed air, and the engine can realize continuous work by matching with continuous supplement of subsequent fuel.

The combustion chamber is the core component of a micro-turbojet engine, and is equivalent to the heart of the engine, the combustion quality of the combustion chamber directly influences the performance level of the engine, and therefore, an internal ignition device of the combustion chamber is very important. At present, a micro turbojet engine generally adopts a mode of heating a ceramic heating rod for ignition, a ceramic igniter generates high-temperature ignition fuel oil by utilizing the self high-resistance heating characteristic of the ceramic igniter in principle, so the ceramic igniter can reach the ignition temperature only by preheating and heating, the fuel oil can be ignited only by contacting with the igniter for a certain time, the ignition time is long, and the efficiency is low; meanwhile, in order to ensure that a layer of thin fuel can be attached to the surface of the ceramic heating rod at the initial ignition stage, the engine can only be started at a specific installation angle, otherwise, at a specific angle, the engine fuel is influenced by gravity, flows through the heating rod rapidly, cannot finish the attachment process, is difficult to ignite successfully, and influences the ignition stability of the engine; in addition, the ceramic heating rod needs to keep a higher temperature through higher voltage and larger current in each ignition process, and in order to ensure the ignition success rate, the duration of high voltage and large current is longer, so that not only is the energy consumption larger, but also the ceramic heating rod is greatly lost, and the service life of the ceramic heating rod is influenced.

Therefore, there is a need for an ignition device in a turbojet combustion chamber that solves the problems of the prior art that the igniter has a long ignition time, is prone to wear, and has an unstable ignition success rate.

SUMMERY OF THE UTILITY MODEL

Aiming at the defects of the prior art, the utility model aims to provide a combustion chamber of a micro turbojet engine, wherein an ignition module in the combustion chamber adopts a mode that a high-voltage arc igniter is matched with a starting fuel injector to ignite the engine, a preheating process is not needed, the ignition time is shortened, the service life of the igniter is long, and the ignition stability and the overall reliability of the micro engine are effectively improved.

In order to achieve the purpose, the utility model discloses a micro turbojet engine combustion chamber which comprises a combustion chamber shell, wherein a main fuel oil supply capillary tube, an evaporation tube and an ignition module are arranged in the combustion chamber shell.

Further specifically, the combustion chamber shell comprises a first sleeve, a second sleeve and a first end cover, the first sleeve is sleeved on the second sleeve, and the first sleeve is connected with the second sleeve through the first end cover.

Further specifically, a through hole is formed in a first sleeve or a first end cover of the combustion chamber shell, and the discharge cathode is arranged on the through hole.

More specifically, the discharge anode penetrates through the through hole and extends into the combustion chamber.

More specifically, the number of the discharge cathodes is at least one.

More specifically, the starting fuel injector is arranged on the combustion chamber shell, and the starting fuel injection direction is aligned with the high-voltage electric arc igniter.

Further specifically, a plurality of air inlets are formed in the first sleeve and the second sleeve of the combustion chamber shell.

Further specifically, the air inlet holes in the first sleeve comprise a first air inlet hole and a second air inlet hole which are sequentially arranged from one end close to the first end cover to the other end, and the first air inlet holes are arranged in a V shape.

Optionally, the aperture of the air inlet hole of the first sleeve gradually increases from one end close to the first end cover to the other end.

Further specifically, the main fuel supply capillary tube is disposed in the evaporation tube.

More specifically, one side of the combustion chamber shell is connected with a second end cover, and the evaporation tube is arranged on the second end cover.

The utility model has the beneficial effects that:

the ignition module in the combustion chamber of the micro turbojet engine ignites the engine by adopting a mode of combining tip discharge of a high-voltage arc igniter and spray of atomized fuel by starting a fuel injector, the high-voltage arc igniter generates an electric arc by utilizing a high-voltage discharge principle, the ignition of the atomized fuel can be instantly finished without a preheating process, and the fuel can be continuously atomized and sprayed by starting the fuel injector, so that the fuel can be continuously combusted in a wider range in the combustion chamber, and the whole ignition time can be shortened; meanwhile, the fuel injection has no limit on the installation angle of the engine, so that the engine is ignited more quickly and easily, and the ignition stability of the engine is improved; in addition, the high-voltage discharge hardly abrades the igniter, so that the service life of the igniter is prolonged, and the overall reliability of the engine is improved.

Drawings

Fig. 1 is a schematic view of the main structure of a turbojet engine according to the utility model;

FIG. 2 is a cross-sectional view taken at A-A of FIG. 1;

FIG. 3 is an enlarged schematic view of the portion B in FIG. 2;

FIG. 4 is a schematic view, partly in section, of a turbojet combustion chamber according to the utility model;

FIG. 5 is an enlarged schematic view of the portion C in FIG. 4;

fig. 6 is a schematic view of the structure of the turbojet engine body of the utility model without the combustion casing;

FIG. 7 is a schematic illustration of a combustor casing configuration in accordance with an embodiment of the present invention;

FIG. 8 is a schematic view of a combustor casing configuration in another embodiment of the present invention;

FIG. 9 is an enlarged view of the portion D of FIG. 8;

fig. 10 is a schematic view of the second end cover structure of the turbojet engine of the utility model.

In the figure: 10. a combustion chamber housing; 110. a first sleeve; 120. a second sleeve; 130. a first end cap; 140. a through hole; 150. an air inlet; 151. a first air intake hole; 152. a second air intake hole; 160. a second end cap; 20. starting the fuel injector; 30. a high voltage arc igniter; 310. a discharge anode; 320. discharging the cathode; 40. a main fuel supply capillary; 50. an evaporation tube; 60. the fuel supply line is started.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1-6, a micro turbojet engine combustion chamber comprises a combustion chamber housing 10, a main fuel oil supply capillary 40, an evaporation tube 50 and an ignition module are arranged in the combustion chamber housing 10, the ignition module comprises a high-voltage arc igniter 30 and a starting fuel injector 20, the high-voltage arc igniter 30 comprises a discharge positive electrode 310 and a discharge negative electrode 320, the discharge positive electrode 310 is a needle electrode, the discharge negative electrode 320 is a tip structure and is arranged beside the discharge positive electrode 310, the discharge positive electrode 310 discharges to the discharge negative electrode 320 to generate a high-voltage arc, and the high-voltage arc igniter 30 is matched with the starting fuel injector 20 to ignite an engine.

As shown in fig. 7 and 8, the combustion chamber housing 10 includes a first sleeve 110, a second sleeve 120 and a first end cap 130, the first sleeve 110 is sleeved on the second sleeve 120, and a central axis of the first sleeve 110 coincides with a central axis of the second sleeve 120, so that a regular annular combustion chamber is formed between the first sleeve 110 and the second sleeve 120, so that flames are uniformly distributed in the combustion chamber, and the first sleeve 110 and the second sleeve 120 are connected through the first end cap 130.

As shown in fig. 2, 3, 8 and 9, the first end cap 130 or the first sleeve 110 of the combustor casing 10 is provided with a through hole 140, and in the present embodiment, the through hole 140 is provided on the first end cap 130. The positive electrode 310 penetrates through the through hole 140 and extends into the combustion chamber, and the negative electrode 320 is disposed on the through hole 140 and integrated with the combustion chamber housing 10. The number of the discharge cathodes 320 is at least one, and in the present embodiment, the number of the discharge cathodes 320 is 2, and the discharge cathodes 320 are symmetrically disposed on two sides of the discharge anode 310.

The high-voltage arc igniter 30 generates a high-frequency voltage by a high-frequency oscillator and further boosts the voltage by a booster to form a very high positive voltage at the end of the discharge anode 310, and since the discharge cathode 320 is directly integrated on the combustion chamber housing 10, the combustion chamber housing 10 is connected with the engine housing by a metal such as a screw, the engine housing is connected with the ground, the combustion chamber housing 10 has a zero potential, a relatively large potential difference is generated between the discharge anode 310 and the discharge cathode 320 of the high-voltage arc igniter 30, and the discharge anode 310 performs a tip discharge on the discharge cathode 320 to generate a high-voltage arc.

The high-voltage electric arc igniter 30 adopts a non-contact point discharge mode, the current and the power consumption of electric arc are very small, the loss of the igniter is very small, not only can energy be saved, but also the service life of the igniter is not influenced, and the integral reliability of the engine is improved.

As shown in fig. 1, 4, 5, and 6, the starting fuel injector 20 is provided on the combustion chamber housing 10 with the starting fuel injection direction directed toward the high-voltage arc igniter 30. In the present embodiment, the starting fuel injector 20 is provided on the first sleeve 110 of the combustion chamber housing 10, and one end thereof is connected to the starting fuel supply line 60. The starting fuel injector 20 is obliquely arranged relative to the first sleeve 110 of the combustion chamber, and the fuel injection direction is aligned to the high-voltage electric arc igniter 30, so that atomized fuel sprayed from the starting fuel injector 20 is directly and accurately injected to the high-voltage electric arc igniter 30 in the ignition process, the ignition of the engine is quicker and easier, and the ignition time is effectively shortened.

The ignition module atomizes the liquid fuel by starting the fuel injector 20, small fuel drops are easy to ignite, meanwhile, the high-voltage arc igniter 30 can instantly ignite the atomized fuel by utilizing electric arcs generated by high-voltage discharge without preheating, and the fuel can be continuously atomized and sprayed by starting the fuel injector 20, so that the fuel can be continuously combusted in a wider range in a combustion chamber, and the whole ignition time can be shortened; meanwhile, the fuel injection has no limit on the installation angle of the engine, so that the engine can be ignited more quickly and easily, and the ignition stability is improved.

As shown in fig. 7, a plurality of air inlet holes 150 are formed in the first sleeve 110 and the second sleeve 120 of the combustion chamber housing 10, the gas outside the combustion chamber enters the combustion chamber through the air inlet holes 150 and is discharged, and partial heat in the combustion chamber is taken away through the heat exchange effect, so that the temperatures of the wall surfaces of the first sleeve 110 and the second sleeve 120 can be reduced, in addition, the air inlet holes 150 also play a role in mixing oil and gas, so that the combustion in the combustion chamber is more uniform, and the outlet temperature distribution is more uniform. The air inlet holes 150 on the first sleeve 110 comprise a first air inlet hole 151 and a second air inlet hole 152 which are sequentially arranged from one end close to the first end cover 130 to the other end, the first air inlet hole 151 is arranged in a V shape, and the aperture of the second air inlet hole 152 is larger than that of the first air inlet hole 151, so that the air inlet amount in the axial direction of the combustion chamber is more uniform, and the combustion effect is effectively improved. The first air inlet holes 151 arranged in a V shape are beneficial to increasing the air inflow of a combustion chamber, so that the combustion is more sufficient, the combustion efficiency is improved, the acceleration performance of the engine in the ignition process is improved, meanwhile, the smooth transition from the successful ignition to the normal operation stage of the engine is facilitated, and the ignition stability is improved.

As shown in fig. 8, in another embodiment, the apertures of the air intake holes 150 on the first sleeve 110 gradually increase from one end close to the first end cover 130 to the other end, because the speed and the amount of the gas gradually decrease in the process of flowing from the first end cover 130 in the axial direction, and the apertures of the air intake holes 150 on the first sleeve 110 gradually increase, the air intake amount in the axial direction of the combustion chamber can be more uniform, and the combustion effect can be effectively improved.

As shown in fig. 4, 6 and 10, one side of the combustor casing 10 is connected to a second end cap 160, and the evaporation tube 50 is disposed on the second end cap 160. Specifically, a plurality of evaporation tubes 50 are fixedly arranged on the inner wall of the second end cover 160, the main fuel oil supply capillary tube 40 is arranged in the evaporation tubes 50 and is communicated with the interior of the combustion chamber, the main fuel oil supply capillary tube 40 is used for supplying fuel oil to the combustion chamber after ignition, the evaporation tubes 50 play a role in preheating the fuel oil, after the engine is ignited, the evaporation tubes 50 are rapidly heated up under the surrounding of flame in the combustion chamber, and when the fuel oil flows into the main fuel oil supply capillary tube 40 arranged in the evaporation tubes 50, the fuel oil is rapidly preheated and sprayed into the combustion chamber in a mist form, so that the combustion of the fuel oil in the combustion chamber is facilitated.

The specific start-up procedure of the micro turbojet is as follows:

1) when an ignition command is sent out, after the electric energy provided by a battery connected with an engine passes through a high-frequency oscillator and a booster, a very high positive voltage is generated at the top of the discharge anode 310 of the high-voltage arc igniter 30, and the discharge anode 310 discharges to the discharge cathode 320 to generate a high-voltage arc; meanwhile, the ignition control module controls the starting motor to be started, and air enters the combustion chamber after being pressurized by the air compressor and the diffuser.

2) The ignition control module controls the starting oil path electromagnetic valve to be opened, the oil pump starts to work, fuel oil in the oil tank flows into the starting fuel oil injector 20 through the starting fuel oil supply pipe 60 through the oil pump, and the fuel oil is accurately injected to an electric arc generated by the discharge of the high-voltage electric arc igniter 30 in a mist form through the starting fuel oil injector 20. The fuel oil does not need to be preheated before ignition, the injected fuel oil forms small-particle fuel oil drops, the energy required by successful ignition of the single fuel oil drops is reduced along with the small volume of the single fuel oil drops, meanwhile, the fuel oil with a certain volume forms a fog-like state after injection, the small-particle fuel oil drops can be fully contacted with the air in the combustion chamber, and favorable conditions are provided for smooth ignition of the small-particle fuel oil drops.

3) After the flame is generated, the ignition control module controls the starting motor to rapidly increase the rotating speed, drives the air compressor to rotate more rapidly, sucks and compresses more air, and enables more compressed air to enter the combustion chamber to participate in combustion after being further pressurized by the diffuser, so that the combustion is more intense, and the air reaches the idling point of the engine more rapidly.

4) As the amount of intake air increases, the ignition control module controls the main line solenoid valve to open and a greater amount of fuel passes through the oil pump and the main line solenoid valve into the main fuel supply capillary 40. The fuel injector 20 is started to enable fuel at the starting part to enter the combustion chamber in an atomized form to participate in combustion, so that the flame area in the combustion chamber is large, the evaporation pipe 50 distributed in the combustion chamber can be heated more uniformly, and due to the fact that the evaporation pipe 50 is rapidly heated under the surrounding of the flame in the combustion chamber, when the fuel flows into the main fuel supply capillary tube 40 arranged in the evaporation pipe 50, the fuel can rapidly complete the preheating process and is sprayed into the combustion chamber in an atomized form, and combustion in the combustion chamber is facilitated.

5) Atomized fuel oil and compressed air in the combustion chamber are combusted more intensely, gas expands after being combusted, and flows through the turbine in the process of being discharged out of the engine to drive the turbine to rotate at an accelerated speed, so that the rotor of the engine rotates at an accelerated speed, the rotating speed of the engine rises, the rotating speed of the gas compressor also rises synchronously, more and more compressed air is combusted more and more intensely, and the starting process is finished until the engine reaches an idle speed.

In conclusion, the utility model provides a combustion chamber of a micro turbojet engine, an ignition module in the combustion chamber adopts a mode of combining point discharge of a high-voltage electric arc igniter 30 and spray of atomized fuel by starting a fuel injector 20 for ignition, a preheating process required in the ignition of a traditional ceramic heating rod is not needed, the ignition time is effectively shortened, and the influence of the installation angle of the engine is avoided, so that the ignition of the engine is quicker and easier, and the ignition stability of the engine is improved; meanwhile, the igniter is hardly abraded by high-voltage discharge, so that the service life of the igniter is prolonged, and the overall reliability of the engine is improved; in addition, the aperture change and distribution design of the air inlet holes 150 on the first sleeve 110 of the combustion chamber shell 10 make the air inlet amount in the axial direction of the combustion chamber more uniform, and the combustion efficiency and the ignition stability of the combustion chamber are improved.

It is to be emphasized that: the above are only preferred embodiments of the present invention, and the present invention is not limited thereto in any way, and any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention are within the scope of the technical solution of the present invention.

Claims

1. The utility model provides a miniature turbojet engine combustion chamber, includes the combustion chamber casing, set up main fuel oil fuel feeding capillary, evaporating pipe and ignition module in the combustion chamber casing, its characterized in that, ignition module includes high-voltage arc point firearm and start fuel sprayer, high-voltage arc point firearm is including discharging positive pole and discharge negative pole, the positive pole of discharging is the needle electrode, the discharge negative pole is tip structure and sets up by the positive pole of discharging, the positive pole of discharging is right discharge negative pole produces high-voltage electric arc, high-voltage arc point firearm with start fuel sprayer cooperatees and ignites the engine.

2. The micro-turbojet engine combustor of claim 1 wherein the combustor housing includes a first sleeve, a second sleeve, and a first end cap, the first sleeve being disposed over the second sleeve, the first sleeve and the second sleeve being connected by the first end cap.

3. The micro-turbojet engine combustor of claim 2, wherein the first sleeve or the first end cap of the combustor casing is provided with a through hole and the negative discharge electrode is provided on the through hole.

4. A micro-turbojet engine combustion chamber according to claim 3, wherein the positive discharge electrode projects into the combustion chamber through the through-hole.

5. The micro turbojet engine combustor of claim 1, wherein the number of negative discharge electrodes is at least one.

6. The turbojet engine combustor of claim 1 wherein the start-up fuel injectors are disposed on the combustor housing with the start-up fuel injection direction directed at the high voltage arc igniter.

7. A micro-turbojet engine combustion chamber according to claim 2, characterized in that the first and second sleeves of the combustion chamber housing are provided with air intake holes.

8. The turbojet engine combustion chamber of claim 7 wherein the air intake ports on the first sleeve include first and second air intake ports disposed in series from one end adjacent the first end cap to the other, the first air intake ports arranged in a V-shape.

9. The micro-turbojet engine combustion chamber of claim 7 wherein the apertures of the air intake apertures of the first sleeve increase progressively from one end proximate the first end cap to the other.

10. The micro turbojet engine combustor of claim 1, wherein the main fuel feed capillary is disposed within the evaporator tube.

11. The micro turbojet engine combustor of claim 1 wherein one side of the combustor housing is attached to a second end cap, the evaporator tube being disposed on the second end cap.