JP2012202227A - Jet engine and method of controlling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scramjet engine, along with a method of controlling the scramjet engine, capable of preventing thermal blocking-up.SOLUTION: This jet engine includes an air flow path forming member installed in an airframe so that an air flow path is formed, and a fuel supply mechanism for introducing fuel into the air flow path. The air flow path includes a front opening, a combustion part for burning the introduced fuel by air taken in via the front opening, and a rear opening connected to the rear of the combustion part and jetting combustion gas generated by the combustion. The air flow path forming member is provided with a gas releasing hole for communicating the air flow path with the outside and an opening-closing member for opening-closing the gas releasing hole.

Description

  The present invention relates to a jet engine and a jet engine control method.

  A flying engine may be equipped with a jet engine to generate a propulsive force. A scramjet engine is known as a jet engine operated during high-speed flight.

  FIG. 1 is a cross-sectional view schematically showing an example of a scramjet engine. As shown in FIG. 1, the scramjet engine 100 includes a cowl 102 (flow path forming member) attached so that an air flow path 104 is formed between the airframe 101 and a fuel supply mechanism 103. Yes. The air flow path 104 includes a front opening 105, a combustion unit 107, and a rear opening 106. The fuel supply mechanism 103 is configured to introduce fuel into the combustion unit 107. During the flight, supersonic air is taken into the air flow path 104 through the front opening 105. The taken-in air is compressed and decelerated, and is guided to the combustion unit 107 while maintaining supersonic speed. In the combustion unit 107, the introduced fuel is combusted by supersonic air to generate combustion gas. The combustion gas expands, accelerates and is injected from the rear opening 106. Thereby, a propulsive force for propelling the airframe 101 is obtained.

  A technique related to the scramjet engine is disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 7-4314). Patent Document 1 discloses a scramjet engine that includes a flow path that includes a front opening, a central cavity, and a rear opening, and includes a device that injects hydrogen into the central cavity. A scramjet engine is disclosed in which a part of the member to be moved is made movable so that the front opening can be closed and an apparatus for injecting oxygen into the central cavity is additionally installed.

Japanese Patent Laid-Open No. 7-4314

  By the way, in a scramjet engine, a thermal blockage phenomenon may occur. FIG. 2 is a diagram schematically showing the state of the scramjet engine when a thermal clogging phenomenon occurs. For example, when the amount of fuel supplied to the combustion unit 107 is excessive, the amount of heat generated in the combustion unit 107 increases. Due to the increase in the calorific value, the pressure in the combustion section 107 is abnormally increased, and a heat blocking state occurs. When the thermal blockage occurs, the inflow of air into the combustion unit 107 is hindered. As a result, the combustion state in the combustor 107 becomes a subsonic combustion state, and the necessary driving force cannot be obtained.

  Therefore, an object of the present invention is to provide a scramjet engine and a control method for the scramjet engine that can prevent thermal blockage.

  A jet engine according to the present invention includes an air flow path forming member attached to the airframe and a fuel supply mechanism for introducing fuel into the air flow path so that an air flow path is formed between the jet engine and the airframe. It comprises. The air flow path is connected to a front opening and a combustion section in which the introduced fuel is burned by air taken in through the front opening, and combustion generated by the combustion is connected to the rear of the combustion section. And a rear opening through which gas is ejected. The air flow path forming member is provided with an air vent that communicates the air flow path with the outside, and an opening and closing member that opens and closes the air vent.

  According to the present invention, the pressure in the combustion section can be reduced by opening the vent hole with the opening / closing member. Thereby, generation | occurrence | production of thermal obstruction | occlusion can be prevented.

  The jet engine control method according to the present invention introduces fuel to the air flow path forming member attached to the airframe and the air flow path so that an air flow path is formed between the airframe and the airframe. A fuel supply mechanism, and the air flow path is connected to a front opening, a combustion part in which the introduced fuel is combusted by air taken in through the front opening, and a rear part of the combustion part A rear opening through which the combustion gas generated by the combustion is jetted, and the air flow path forming member opens and closes the air holes and the air holes that communicate the air flow path with the outside. A control method of a jet engine provided with an opening / closing member. This control method detects the state of the combustion part, generates state data indicating a detection result, determines whether the combustion part is in a heat-blocked state based on the state data, And a step of controlling the opening / closing member so that the air vent is opened when it is determined that the opening is closed.

  The present invention provides a scramjet engine and a scramjet engine control method capable of preventing thermal blockage.

It is sectional drawing which shows an example of a scramjet engine roughly. It is a figure which shows roughly the mode of a scramjet engine when the thermal obstruction | occlusion phenomenon generate | occur | produced. 1 is a schematic view showing a scramjet engine according to a first embodiment. It is the schematic which shows the mode of a scramjet engine when there exists a danger that a thermal obstruction | occlusion state will generate | occur | produce. It is the schematic which shows the mode of a scramjet engine when an air vent hole is open | released. It is the schematic which shows the state of the scramjet engine when a thermal obstruction | occlusion state generate | occur | produced. It is the schematic which shows the state of the scramjet engine at the time of restart.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 3A is a schematic view showing the scramjet engine 1 according to the present embodiment. As shown in FIG. 3A, the scramjet engine 1 includes a cowl 3 (flow path forming member), a fuel supply mechanism 8, a control device 10, and a state detection device 11 that are attached to the lower part of the flying aircraft body 2. I have.

  The cowl 3 is attached to the body 2 such that an air flow path 4 is formed between the cowl 3 and the body 2. The air flow path 4 includes a front opening 5, a combustion unit 7, and a rear opening 6. The front opening 5 is a portion that takes in air. The combustion part 7 is a part which burns fuel with the taken-in air and generates combustion gas. The rear opening 6 is a part for ejecting combustion gas generated in the combustion unit 7. In the air flow path 4, the upstream region of the combustion unit 7 is formed so that the cross-sectional area gradually decreases toward the downstream side. Moreover, in the air flow path 4, the area | region of the downstream of the combustion part 7 is formed so that a cross-sectional area may become large gradually toward the downstream.

  Further, the cowl 3 is provided with an air vent 13 and an opening / closing member 9. The air escape hole 13 is provided in order to make the combustion part 7 communicate with the outside. The air escape hole 13 passes through the cowl 3. On the other hand, the opening / closing member 9 is a member that opens and closes the vent hole 13.

  The fuel supply mechanism 8 is provided to supply fuel to the combustion unit 7. The fuel supply mechanism 8 includes a combustion nozzle (not shown) disposed in the combustion unit 7. The fuel supply mechanism 8 supplies fuel (for example, hydrogen and jet fuel) to the combustion unit 7 through the combustion nozzle.

  The state detection device 11 detects the state of the combustion unit 7 and generates state data indicating the detection result. Examples of the detected state of the combustion unit 7 include a wall pressure in the combustion unit 7 and a temperature in the combustion unit 7. Further, when the combustion unit 7 is provided with a pitot tube, the pitot pressure may be detected as the state of the combustion unit 7.

  The control device 10 has a function of opening and closing the opening / closing member 9 based on the state data. The control device 10 is realized by a computer, for example, and is realized by a CPU executing a control program stored in advance in a ROM (Read Only Memory) or the like.

  Then, the control method of the scramjet engine 1 which concerns on this embodiment is demonstrated.

  In the scramjet engine 1 according to this embodiment, supersonic air is taken into the air flow path 4 through the front opening 5. The taken-in air is compressed in the upstream region of the combustion unit 7, decelerated within a range in which the supersonic state is maintained, and guided to the combustion unit 7. In the combustion unit 7, the fuel supplied from the fuel supply mechanism 8 is combusted by supersonic air, and combustion gas is generated. The generated gas expands, accelerates, and is injected from the rear opening 6 in the downstream region of the combustion unit 7. Thereby, the thrust for propelling the body 1 is obtained.

  Here, when the fuel is supplied excessively, the temperature of the combustion section 7 may rise abnormally, and a thermal blockage may occur. FIG. 3B is a schematic diagram illustrating a state of the scramjet engine 1 when there is a risk of occurrence of a thermal blockage state. When the temperature of the combustion section 7 rises due to excessive fuel supply or the like, as shown in FIG. 3B, the pressure in the combustion section 7 rises and the combustion state becomes a subsonic combustion state. In this case, the control device 10 detects that there is a risk of a thermal occlusion state based on the pressure data. Specifically, a threshold value indicating a pressure when there is a risk of occurrence of a thermal blockage is set in the control device 10 in advance. The control device 10 compares the state data acquired from the state detection device 11 with a set threshold value, and determines that there is a risk of a thermal occlusion state when the value indicated by the state data exceeds the threshold value. . The propulsive force required by the airframe 1 depends on the altitude, speed, acceleration of the airframe 1, the temperature of the combustion unit 7, and the like. Therefore, it is preferable that the threshold value is set in association with altitude, speed, acceleration, temperature of the combustion unit 7, and the like. In this case, the control device 10 acquires altitude data, speed data, acceleration data, and temperature data from an altimeter, a speedometer, an accelerometer, and a thermometer (not shown), respectively. Then, based on the acquired data, the corresponding threshold value is identified, and the identified threshold value is compared with the state data to determine whether there is a risk of occurrence of a thermal blockage state.

  When the controller 10 determines that there is a risk of the occurrence of a thermal blockage, the controller 10 controls the opening / closing member 9 so that the air vent 13 is opened. FIG. 3C is a schematic view showing a state of the scramjet engine 1 when the air vent 13 is opened. As shown in FIG. 3C, by opening the vent hole 13, air and a part of the combustion gas are discharged from the combustion unit 7 to the outside through the vent hole 13. Thereby, the pressure of the combustion part 7 falls. Therefore, the occurrence of a heat blocking state is prevented.

  Thereafter, the control device 10 continues to monitor the state data. The control device 10 controls the opening / closing member 9 so that the vent hole 13 is closed when there is no risk of the occurrence of the thermal blockage. Thereafter, the scramjet engine 1 operates in a normal state.

  As described above, according to the present embodiment, by providing the vent hole 13, part of the air and combustion gas in the combustion section 7 can be released, and the pressure in the combustion section 7 is reduced. be able to. As a result, it is possible to prevent the thermal blockage state while the operation of the scramjet engine is continued.

  In addition, it is preferable that the vent hole 13 is connected to a portion where the heat blockage is likely to occur in the combustion portion 7, and from this viewpoint, it is provided in the vicinity of the combustion nozzle or on the downstream side of the combustion nozzle. Is preferred.

(Second Embodiment)
Next, the second embodiment will be described. In the present embodiment, the operation of the control device 10 is devised. Since other points can be the same as those in the first embodiment, a detailed description thereof will be omitted.

  According to the first embodiment, the pressure of the combustion unit 7 can be reduced, so that the occurrence of a thermal blockage state can be avoided in advance. However, there is a possibility that a thermal blockage may occur suddenly due to disturbance of outside air during flight. Should a thermal blockage occur, the fuel supply by the fuel supply mechanism 8 is temporarily stopped. And after a thermal obstruction | occlusion state is eliminated, reignition is performed in the combustion part 7, and the scramjet engine 1 is restarted. Here, at the time of restart, a sufficient amount of fuel needs to be supplied to the combustion unit 7. However, when the fuel is supplied excessively, the temperature rises abnormally and the heat blockage state occurs again. Therefore, it is desirable that it can be easily restarted. Therefore, in this embodiment, the operation at the time of restart is devised.

  FIG. 4A is a schematic diagram illustrating a state of the scramjet engine 1 when a thermal blockage state occurs. Based on the state data sent from the state detection device 11, the control device 10 monitors whether or not a thermal blockage state has occurred. When the thermal blockage occurs, as shown in FIG. 4A, the control device 10 controls the operation of the fuel supply mechanism 8 so that the supply of fuel is stopped.

  Thereafter, the control device 10 controls the opening / closing member 9 so that the air vent 13 is opened. The control device 10 monitors the state data and determines whether or not the thermal blockage state has been resolved. When the thermal blockage state is resolved, the control device 10 restarts.

  FIG. 4B is a schematic diagram showing a state of the scramjet engine 1 at the time of restart. The control device 10 controls the fuel supply mechanism 8 so that fuel is supplied to the combustion unit 7, and controls an ignition device (not shown) to perform ignition. At this time, the control device 10 controls the fuel supply mechanism 8 and the opening / closing member 9 so that the fuel is supplied to the combustion unit 7 in a state where the vent hole 13 is opened.

  Here, according to this embodiment, since the air vent 13 is opened at the time of restart, it is possible to prevent a heat blockage from occurring at the time of restart. Therefore, it becomes possible to supply sufficient fuel to the combustion part 7, and restart can be performed reliably.

  In the present embodiment, it is preferable that the vent hole 13 is provided near or downstream of the combustion nozzle 12. By providing the vent hole 13 in the vicinity of the combustion nozzle 12 or on the downstream side, it is possible to effectively reduce the pressure in the portion where the heat blocking state occurs. However, the vent hole 13 may be provided on the upstream side of the combustion nozzle 12. When the vent hole 13 is provided on the upstream side of the combustion nozzle 12, a situation in which it is difficult to take in air from the front opening 5 due to an increase in the pressure of the combustion unit 7 is avoided, and it is easy to restart.

  The present invention has been described above using the first and second embodiments. These embodiments are not independent from each other, and can be used in combination within a consistent range.

1 Scramjet engine 2 Airframe 3 Cowl (air flow path forming member)
DESCRIPTION OF SYMBOLS 4 Air flow path 5 Front opening 6 Back opening 7 Combustion part 8 Fuel supply mechanism 9 Opening / closing member 10 Control apparatus 11 State detection apparatus 12 Fuel nozzle 13 Air vent 100 Scramjet engine 101 Airframe 102 Cowl (Air flow path formation member)
DESCRIPTION OF SYMBOLS 103 Fuel supply mechanism 104 Air flow path 105 Front opening 106 Back opening 107 Combustion part

Claims (7)

An air flow path forming member attached to the fuselage so that an air flow path is formed;
A fuel supply mechanism for introducing fuel into the air flow path;
Comprising
The air flow path is
A front opening,
A combustion section in which the introduced fuel is combusted by the air taken in through the front opening;
A rear opening that is connected to the rear of the combustion section and from which the combustion gas generated by the combustion is ejected;
In the air flow path forming member,
An air vent that communicates the air flow path with the outside;
A jet engine provided with an opening and closing member for opening and closing the air vent. A jet engine according to claim 1,
Furthermore,
A state detection device that detects a state of the combustion section and generates state data indicating a detection result;
Based on the state data, it is determined whether or not there is a risk that a thermal blockage state occurs in the combustion section, and when it is determined that there is a risk, the opening / closing member is opened so that the vent hole is opened. A control device for controlling
A jet engine comprising: A jet engine according to claim 2,
The state detection device detects a pressure in the combustion unit or a temperature in the combustion unit as a state in the combustion unit.
Jet engine. A jet engine according to claim 2 or 3,
The fuel supply mechanism includes a fuel nozzle that ejects the fuel to the combustion unit,
The exhaust hole is a jet engine provided in the vicinity of or downstream from the fuel nozzle. A jet engine according to any one of claims 2 to 4,
When the combustion is stopped in the combustion section, the control device controls operations of the opening / closing member and the fuel supply mechanism so that the fuel is supplied to the combustion section with the air vent hole opened. A jet engine that restarts. A jet engine according to any one of claims 1 to 5,
The jet engine is configured such that the air flow path burns supersonic air in the combustion section. An air flow path forming member attached to the airframe so that an air flow path is formed between the airframe and the airframe;
A fuel supply mechanism for introducing fuel into the air flow path;
Comprising
The air flow path is
A front opening,
A combustion section in which the introduced fuel is combusted by the air taken in through the front opening;
A rear opening that is connected to the rear of the combustion section and from which the combustion gas generated by the combustion is ejected;
In the air flow path forming member,
An air vent that communicates the air flow path with the outside;
A control method of a jet engine provided with an opening and closing member for opening and closing the air vent,
Detecting the state of the combustion section and generating state data indicating a detection result;
Based on the state data, it is determined whether or not there is a risk that a thermal blockage state occurs in the combustion section, and when it is determined that there is a risk, the opening / closing member is opened so that the vent hole is opened. A step of controlling
A method for controlling a jet engine comprising:

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