JP2002030941A - Turbo fan jet engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turbo fan jet engine to generate high pressure exhaust gas, improve a driving force including a propulsion force, realize low fuel consumption, and further reduce the generation of a noxious material in exhaust gas by producing a condition to promote combustion reaction in a combustion chamber by utilizing plasma and shortening a combustion period in a combustion engine in a turbo fan jet engine. SOLUTION: In the turbo jet engine provided with a combustion chamber 23 and a fuel injection nozzle 2 to inject fuel toward the combustion chamber 23 and constituted that fuel through the fuel injection nozzle 2 is burnt in the combustion chamber 23, a discharge electrode 7 is provided to generate discharge in a fuel passage 6 of the fuel injection nozzle 2 to inject fuel in the combustion chamber 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbofan jet engine for an aircraft using a plasma generator.

[0002]

2. Description of the Related Art In a turbofan jet engine for an aircraft, air taken in from an air intake port on the front of the engine is accelerated by a propeller-like blade attached in front of a compressor to accelerate the air taken in from the front to the rear. Send compressed air. A part of the accelerated air flow is further compressed by the compressor, and then mixed as jet air with the jet fuel in the combustion chamber and burned. The high-temperature and high-pressure exhaust gas generated by this combustion is passed through a turbine. At this time, the turbine is driven by high-temperature and high-pressure exhaust gas to obtain a driving force of a series of compressors, and then vigorously ejected as exhaust gas to the rear of the engine to obtain propulsion. On the other hand, the remaining accelerated compressed air that has not passed through the series of combustion strokes is discharged from the engine through a bypass.

[0003]

However, in a combustion chamber of a turbofan jet engine for an aircraft, maximum heat release and minimum pressure loss are required in a limited space in order to improve propulsion. In addition, there is a problem that the flow rate of the compressed air supplied to the combustion chamber must be complete to completely burn in the primary zone in the combustion chamber without the flame being blown out quickly.

Accordingly, the present invention improves the responsiveness of combustion by creating conditions for promoting the combustion reaction in the combustion chamber and shortening the combustion time in the combustion in the primary zone of the combustion chamber of the turbofan jet engine. It is another object of the present invention to provide a turbofan jet engine in which unburned hydrocarbons and nitrogen in combustion gas due to incomplete combustion are reduced.

[0005]

According to a first aspect of the present invention, there is provided a fuel supply apparatus comprising: an injection hole for injecting fuel in a mist state; and a fuel passage for guiding fuel from fuel supply means to the injection hole. In a combustion chamber of a turbofan jet engine having an injection nozzle and burning fuel from the fuel injection nozzle, a plasma generation mechanism for generating a discharge in the fuel passage through which fuel injected from the injection hole passes is provided. Further provisions are made.

According to the first aspect, in the operation of the turbofan jet engine, when fuel is injected into the combustion chamber by the fuel injection nozzle, an air-fuel mixture with the compressed air from the compressor is generated. The compressed air from the compressor becomes high-temperature air by being compressed. Therefore, since the generated air-fuel mixture is in a high temperature state, the flame is self-supplied after the ignition by the ignition plug at the start of combustion, and the air-fuel mixture is burned. During the fuel injection, the plasma generating mechanism discharges the fuel in the fuel passage in the fuel injection nozzle, thereby charging the fuel passing through the fuel passage. As described above, when the fuel immediately before the injection is charged, ionization of the fuel is promoted when generating the air-fuel mixture,
Since the combustion reaction is accelerated, the time required from the start of the combustion reaction to the completion of the combustion reaction is reduced. As a result, the fuel combustion efficiency is improved as compared with the conventional turbofan jet engine, and the generation of unburned hydrocarbons and hydrocarbons due to unburned fuel is reduced.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the plasma generating mechanism further comprises a pair of discharge electrodes disposed apart from each other on a tube wall of the fuel passage, A plasma generator electrically connected to the two discharge electrodes and applying a high-frequency voltage between the two discharge electrodes.

According to the second aspect, the plasma generator applies a high frequency voltage to the discharge electrode to generate a discharge in the fuel passage of the fuel injection nozzle. As a result, the fuel passing through the fuel passage is charged, and the ionization of the fuel when the air-fuel mixture is generated after the injection is promoted.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, a fuel injection detecting means for detecting a fuel injection state of the fuel injection nozzle, and a fuel injection detecting means for detecting a fuel injection state by the fuel injection nozzle. And a plasma control unit that sets the detection of the start of injection as a condition for starting application to the discharge electrode.

According to the third aspect, when the start of the injection by the fuel injection nozzle is detected by the fuel injection detecting means, the plasma generator starts applying a high voltage to the discharge electrode. As a result, discharge is generated accurately for the fuel immediately before being injected by the fuel injection nozzle.

According to a fourth aspect of the present invention, in addition to the configuration of the third aspect, the plasma control means determines a voltage applied to the discharge electrode based on a result of detection of an injection amount by the fuel injection detection means. It is different depending on.

According to the fourth aspect, when the fuel injection detecting means detects the amount of fuel injected by the fuel injection nozzle, the voltage applied to the discharge electrode is changed in accordance with the amount of injected fuel. It is changed to a value according to the amount. As a result, plasma having an intensity corresponding to the amount of injected fuel is generated, and the fuel is ionized efficiently.

According to a fifth aspect of the present invention, in addition to the configuration of the fourth aspect, the plasma generating mechanism includes a discharge coil provided on a tube wall of the fuel passage, and a discharge coil provided at both ends of the discharge coil. A plasma generator that is electrically connected and supplies a high-frequency current to the discharge coil.

According to the fifth aspect, the plasma generator supplies a high-frequency current to the discharge coil to generate a discharge in the fuel passage of the fuel injection nozzle by the induced electromotive force. As a result, the fuel passing through the fuel passage is charged, and the ionization of the fuel when the air-fuel mixture is generated after the injection is promoted.

According to a sixth aspect of the present invention, in addition to the configuration of the fifth aspect, a fuel injection detecting means for detecting a fuel injection state by the fuel injection nozzle, and an injection start by the fuel injection detecting means. And a plasma control unit that sets the detection as a condition for starting current supply to the discharge coil.

According to the sixth aspect, when the start of injection by the fuel injection nozzle is detected by the fuel injection detecting means, the plasma generator starts to supply a high-frequency current to the discharge coil. As a result, discharge is generated accurately for the fuel immediately before being injected by the fuel injection nozzle.

According to a seventh aspect of the present invention, in addition to the configuration of the sixth aspect, the plasma control means determines whether a current flowing through the discharge coil is detected by the fuel injection detection means. It is different depending on.

According to the seventh aspect, when the fuel injection detecting means detects the amount of fuel injected by the fuel injection nozzle, the current supplied to the discharge coil corresponds to the amount of injected fuel. It is changed to a value according to the amount. As a result, plasma having an intensity corresponding to the amount of injected fuel is generated, and the fuel is ionized efficiently.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A turbofan jet engine according to one embodiment of the present invention will now be described with reference to FIGS.
A description will be given based on FIG.

The fuel injection nozzle shown in FIGS. 1 and 2 is of a type called an air spray nozzle 2 mainly used in an annular type combustion chamber, and is a turbofan jet engine shown in FIGS. 5 and 6. As a fuel injection system.

The fuel 6 sent to the combustion chamber 23 is injected into the combustion chamber 23 through the fuel injection nozzle 2 from the fuel tank via the fuel pump through the regulator, and burns with the compressed air 28 to generate high-temperature and high-pressure combustion gas. And the driving force 35, 36, 37 of the turbine. The air spray nozzle 2, which is a fuel injection nozzle, has a feed arm 1 extending from a pipe from a regulator, a fuel injection port 8 attached to the end of the feed arm, and compressed air swirling devices 3 and 4 integrated with each other. It has a structure as a structure. In the feed arm 1, a device including a weight and a spring is incorporated as a distribution device 5 for finally adjusting the fuel supplied to the combustion chamber. The fuel 6 sent from the distributor 5 is sent to the tip of the feed arm 1. At the tip of the feed arm 1, there are swirlers 3 and 4 which take in compressed air of primary combustion air 28 in proportion to the flow rate of the fuel 6. This turning device has a two-layer structure of an outer side and an inner side. This combustion air swirl device 3
And 4 generate swirl of combustion air by rotating the blades. The fuel 6 is injected from the front of the inner swirling device, and is atomized by contacting the swirl air generated inside. The atomized fuel is further exposed to swirl air generated outside, thereby preventing the atomized fuel from being biased and uniformly spraying the fuel into the combustion chamber 23 to stabilize combustion.

In order to electrically ionize the jet fuel 6, a pair of ring-shaped discharge electrodes 7 are arranged apart from each other in a fuel passage on the upstream side of the distributor 5 in the feed arm of the fuel injection nozzle. A plasma generator 10 is electrically connected to the discharge electrode 7.
A battery 9 and a plasma control device 11 are connected to the plasma generation device 10 to form a plasma control system 12. The plasma generator 10 receives a supply of power from the battery 9 and applies a high-frequency voltage to the discharge electrode 7. The plasma controller 11 receives signals from the throttle opening sensor, detects the state of fuel injection by the fuel injection nozzle 2 based on these signals, and controls the driving of the plasma generator 10.

By providing the plasma generator 10 in the fuel passage leading to the combustion injection nozzle, the fuel 6 pumped from the regulator passes through the fuel passage 1 in the feed arm. In the fuel injection nozzle 2 of the present embodiment, at the time of this injection, the plasma generator 10 applies a high frequency voltage to both the discharge electrodes 7 to generate a discharge in the fuel passage. As a result, a corona discharge is generated around the two discharge electrodes 7 and the fuel 6 passing through the fuel passage
Is charged. When the charged fuel 6 is subsequently injected into the combustion chamber 23 to generate an air-fuel mixture, ionization of the fuel 6 is promoted. By promoting ionization of the fuel 6, ideal perfect combustion can be promoted in the combustion chamber 23,
Higher-pressure combustion gas can be generated with less fuel 6 to obtain higher propulsion.

Next, the operation and effect of the present embodiment configured as described above will be described. FIG. 7 shows a plasma control routine for controlling the plasma generator 10 executed by the control device.

First, in step S10, it is determined whether the plasma generator 10 needs to be driven. Specifically, it is determined whether or not the fuel pressure signal P is greater than a predetermined value α. The predetermined value α is set to a value of a hydraulic pressure (referred to as a valve opening pressure) required to start fuel injection from the fuel injection nozzle 2. If this determination condition is not satisfied, that is, if the fuel 6 has not been injected into the combustion chamber 23, step S10 is repeated. On the other hand, if the determination condition is satisfied, that is, if the fuel injection into the combustion chamber 23 has been started, the process proceeds to step S20, and the driving of the plasma generator 10 is started.

Specifically, based on the throttle opening signal Q and the fuel pressure signal P, a plasma having an optimum intensity is generated with respect to the amount of fuel injected (determined) into the fuel chamber 23. Thus, the plasma generator 10 is controlled. Specifically, a high voltage required to generate plasma of a predetermined intensity is applied to the discharge electrode 7. As a result, a corona discharge is generated from the discharge electrode, ions are filled around the discharge electrode, and the fuel in the fuel injection nozzle is charged and ionized.

In the next step S30, it is determined whether the driving of the plasma generator 10 needs to be terminated. See Fuel 6
Is determined to be equal to or less than the predetermined value β. The predetermined value β is set to a value of a hydraulic pressure (called a valve closing pressure) when fuel injection from the fuel injection nozzle 2 ends. If this determination condition is not satisfied, that is, the combustion chamber 2
If the fuel injection into the fuel cell 3 continues, the drive control of the first plasma generator 10 is continued in step S20.
On the other hand, if the determination condition is satisfied, that is, if the fuel injection into the combustion chamber 23 has been completed, the process proceeds to the next step S40, in which the driving of the plasma generator 10 is stopped, and the plasma control is stopped. End the routine.

In the plasma control routine, the combustion chamber 2
When fuel injection to the fuel cell 3 is started, the plasma generator 10
, The application of a high voltage to the discharge electrode 7 is started, so that discharge can be accurately generated toward the injected fuel 6.

In addition, since the voltage applied to the discharge electrode is varied in accordance with the detection result of the injection amount to control the intensity of the generated plasma, for example, the load on the engine is increased and the combustion chamber Even when the fuel is injected, the high-concentration fuel in the air-fuel mixture can be efficiently charged and ionized by increasing the plasma intensity.

The combustion reaction is, in other words, an oxidative decomposition reaction of a combustible substance by oxygen. Generally, when a substance to be subjected to a chemical reaction is ionized in advance, the time required for the reaction is reduced. From this, it is considered that if the combustible substance is ionized also in the combustion reaction, the reaction can be efficiently performed. Therefore, when the fuel in the air-fuel mixture is ionized in the combustion chamber 23, the primary zone (PRI)
Combustion occurs intensively in the MARY ZONE 30 and the subsequent combustion reaction also proceeds promptly. As a result, the combustion explosion of the fuel is promoted, and most of the injected fuel is burned in the dilution zone (DI).
(LUTION ZONE) 31. Therefore, unlike the conventional engine, the phenomenon that the fuel remains unburned up to the dilution zone 31 and the combustion reaction is prolonged hardly occurs.

As described above, according to the present embodiment, since the combustion period in the combustion chamber 23 is shortened, non-combustible hydrocarbons and nitrogen generated by unburned fuel are reduced, and this air pollutant is reduced. Emissions can be significantly reduced.

In general, in a turbofan jet engine which obtains propulsion and driving force by combustion explosion of fuel, the performance is dominated by the combustion period, and the shorter the combustion period, the higher the thermal efficiency and the better. An effect of improving pressure loss and combustion stability can be obtained. In the present embodiment, as described above, since the combustion reaction is concentrated in a short time by shortening the post-combustion period of the combustion, it is possible to increase the output and improve the responsiveness of the turbofan jet engine. .

Further, according to the present embodiment, the combustion chamber 23
Since the thermal efficiency and the combustion stability are improved, it is possible to generate high-temperature and high-pressure combustion gas with less fuel 6 when trying to obtain the same output. Accordingly, stable combustion can be performed in the combustion chamber 23 even if the degree of compression of the compressed air changes due to a flight altitude difference due to a take-off climb horizontal flight or the like. In addition, the stable combustion in the combustion chamber 23 can improve poor engine blowing.

That is, when the fuel injection by the fuel injection nozzle 2 is started in the combustion chamber 23, the application of the high-frequency voltage from the plasma generator 10 to the discharge electrode 7 is started. It is possible to discharge accurately to the fuel 6 immediately before the passing fuel.
Further, since the intensity of the generated plasma is controlled by applying a high-frequency voltage corresponding to the fuel injection amount to the discharge electrode 7, for example, the load on the engine increases,
Even when a large amount of fuel is injected from the fuel injection nozzle 2, by increasing the plasma intensity, the high flow rate fuel 6 in the fuel passage can be charged efficiently.

In this embodiment, since only the fuel injection nozzle 2 needs to be changed, it is not necessary to make a significant change to the conventional turbofan jet engine. That is, since the discharge electrode 7 for generating plasma is incorporated in the fuel passage leading to the fuel injection nozzle 2, it is possible to easily improve the conventional turbofan jet engine without any change in the structure of the combustion chamber itself. it can.

In the present embodiment, the above-described discharge electrode 7
In addition, it is possible to reduce the weight and compactness of the equipment constituting the plasma control system 12, such as the plasma generator 10. Furthermore, since these devices do not involve a mechanical drive, they are not easily affected by engine vibration.
Therefore, it is possible to increase the number of devices relatively easily and minimize the increase in cost.

The present invention can be embodied in another embodiment described below.

(1) In the present embodiment, a high-frequency voltage is applied to a pair of spaced-apart discharge electrodes 7 as a plasma generation mechanism in a fuel passage to generate a discharge. A method may be adopted. For example, FIGS. 2 and 4
As shown in the figure, the discharge coils 13 and 2
2 can be generated by applying a high-frequency current to the discharge coils 13 and 22 to generate a discharge in the fuel passage by induced electromotive force.

(3) In the present embodiment, a type called an air spray nozzle (FIGS. 1 and 2) used in an annular type combustion chamber is shown as a fuel injection nozzle. It may be an injection nozzle.
For example, it may be a fuel injection nozzle 14 typified by a double nozzle (FIGS. 3 and 4) used in a multiple type, a tubboannular type combustion chamber or the like. The fuel injection nozzle 14 of this double nozzle has an injection port of primary 1
7 and two independent orifices, the main fuel manifold 19. One orifice is smaller than the other. A small orifice is responsible for fuel injection when the fuel injection flow is low, while a large orifice is responsible for fuel injection when the pressure increases and the fuel flow is high. Pressure Rise Valves for Each Manifold 17
And 19 to distribute the fuel. This method achieves good atomization over a wide range. In such a double nozzle fuel injection nozzle 14,
Similarly, a pair of discharge electrodes 21 is disposed in a fuel passage for guiding fuel to the injection hole, or a discharge coil 22 is disposed on a tube wall, and a high-frequency voltage is applied to these or a high-frequency current is applied thereto. Thus, a discharge can be generated in the fuel passage.

(4) The plasma control device 11 may detect the fuel injection state by detecting means other than the throttle opening Q and the fuel supply oil pressure P. For example, the injection state of the fuel injected into the combustion chamber 23 may be detected by detecting the operating states of the governor and the timer of the fuel injection pump.

[0041]

According to the first aspect of the invention, by charging the fuel immediately before the injection in the fuel passage of the fuel injection nozzle, the ionization of the injected fuel can be promoted and the combustion reaction can be promoted. As a result, the combustion period can be shortened, and the output of the engine can be increased and the responsiveness can be improved by centralizing the combustion. In addition, it is possible to reduce pollutants such as non-combustible hydrocarbons and nitrogen in exhaust gas due to unburned fuel.

According to the second aspect, in addition to the effects of the first aspect, by generating a plasma in the fuel passage to generate plasma, the fuel immediately before the injection can be effectively charged.

According to the third aspect, in addition to the effects of the first or second aspect, the fuel is discharged toward the fuel immediately before the injection into the combustion chamber, thereby accurately charging and ionizing the fuel. Can be.

According to the fourth aspect, in addition to the effect of the third aspect, by generating a discharge having an intensity corresponding to the amount of fuel injected into the combustion chamber, the fuel can be efficiently charged and ionized. it can.

According to the fifth aspect, by generating a discharge in the fuel passage to generate plasma, the fuel immediately before the injection can be effectively charged.

According to the sixth aspect, in addition to the effect of the fifth aspect, by discharging toward the fuel immediately before the injection, the fuel can be accurately charged and ionized.

According to the seventh aspect, in addition to the effect of the sixth aspect, by generating a discharge having an intensity corresponding to the amount of injected fuel, the fuel can be efficiently charged and ionized.

[0048]

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a fuel injection nozzle of an air spray nozzle type of a turbofan jet engine according to a first embodiment of the present invention.

FIG. 2 is a partial sectional view showing a fuel injection nozzle of an air spray nozzle type of a turbofan jet engine according to a second embodiment of the present invention.

FIG. 3 is a partial cross-sectional view showing a fuel injection nozzle of a turbofan jet engine according to a third embodiment of the present invention, which is a double nozzle type.

FIG. 4 is a partial cross-sectional view showing a fuel injection nozzle of a turbofan jet engine according to a fourth embodiment of the present invention, which uses a double nozzle.

FIG. 5 is a partial sectional view showing a main part of a combustion chamber of a turbofan jet engine according to the first and fourth embodiments of the present invention.

FIG. 6 is a partial cross-sectional view showing a main part of a turbofan jet engine according to first and fourth embodiments of the present invention.

FIG. 7 is a flowchart illustrating a plasma control processing routine.

[Explanation of symbols]

1. Feed arm 2. 2. Fuel injection nozzle by air spray nozzle type 3. Inner swirl generating blades 4. Outer swirl generating blades 5. Distributor that finally regulates the fuel 6. Fuel and fuel pipe Discharge electrode 8. Fuel injection port 9. Battery for plasma generator 10. Plasma generator 11. Plasma control device 12. Plasma control system 13. Discharge coil 14. 14. Fuel injection nozzle by double nozzle type Fuel and fuel pipe for primary orifice 16. Filter 17. Primary orifice 18. Fuel and fuel pipe for main orifice 19. Main orifice 20. Air orifice 21. Discharge electrode 22. Discharge coil 23. Combustion chamber 24. Frame tube 25. Air casing 26. Fuel injection nozzle 27. Spark plug 28. Primary combustion air 29. Secondary combustion air or cooling air 30. Primary combustion zone ((PRIMARY ZON
E)) 31. Dilution combustion zone
ZONE) 32. Low pressure compressor (fan) 33. Medium pressure compressor 34. High pressure compressor 35. High pressure turbine 36. Medium pressure turbine 37. Low pressure turbine

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[Procedure amendment]

[Submission date] July 18, 2000 (2007.1.
8)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

Claims (7)

[Claims] 1. A fuel injection nozzle having an injection hole for injecting fuel in a mist state and a fuel passage for guiding fuel from a fuel supply means to the injection hole, wherein the fuel from the fuel injection nozzle is burned. The turbofan jet engine according to claim 1, further comprising a plasma generation mechanism for generating a discharge in the fuel passage through which the fuel injected from the injection hole passes in the combustion chamber of the turbofan jet engine. 2. The plasma generating mechanism comprises: a pair of discharge electrodes disposed apart from each other on a tube wall of the fuel passage;
The turbofan jet engine according to claim 1, further comprising: a plasma generator electrically connected to the two discharge electrodes and applying a high-frequency voltage between the two discharge electrodes. 3. A fuel injection detecting means for detecting a state of fuel injection by the fuel injection nozzle, and a plasma control means for detecting the start of injection by the fuel injection detecting means as a condition for starting application to the discharge electrode. The turbofan jet engine according to claim 2, further comprising: 4. The apparatus according to claim 3, wherein said plasma control means changes a voltage applied to said discharge electrode in accordance with a result of detection of an injection amount by said fuel injection detection means. Turbofan jet engine. 5. A plasma generating mechanism, comprising: a discharge coil provided on a tube wall of the fuel passage; a plasma generator electrically connected to both ends of the discharge coil, and supplying a high-frequency current to the discharge coil. The turbofan jet engine according to claim 1, further comprising: 6. A fuel injection detecting means for detecting a state of fuel injection by the fuel injection nozzle, and a plasma control means for detecting the start of injection by the fuel injection detecting means as a condition for starting energization of the discharge coil. The turbofan jet engine according to claim 5, further comprising: 7. The plasma processing apparatus according to claim 6, wherein the plasma control means changes a current supplied to the discharge coil according to a result of detection of an injection amount by the fuel injection detection means. Turbofan jet engine.