A system and method for suppressing air intake distortion during a ski jump of a carrier-based aircraft

Abstract

The present application provides an intake distortion suppression system and method for a carrier aircraft during a ski-jump takeoff, belonging to the field of aero-engine technology. The intake distortion suppression system comprises: jet injection nozzles disposed on decks on both sides of an initial position of the carrier aircraft, wherein air jets flowing out of the jet injection nozzles are directed toward below an auxiliary intake valve of the carrier aircraft; a high-pressure gas tank disposed in a deck compartment; and a connecting pipe connecting the jet injection nozzle and the high-pressure gas tank, wherein the connecting pipe is provided with a control valve. During a ski-jump takeoff of the carrier aircraft, a jet airflow directed toward below the auxiliary intake valve is emitted through the jet injection nozzles. The jet airflow can suppress belly-recirculating exhaust gas induced by a large-scale recirculation zone at the belly of the carrier aircraft, thereby reducing engine intake temperature distortion caused by high-temperature exhaust gas induced by the baffle at the rear of the carrier aircraft being recirculated and inhaled into the engine.

Description

Technical Field

[0001] The present application belongs to the field of aero-engine technology, and in particular relates to a system and method for suppressing intake distortion during a ski-jump process of a carrier-based aircraft. Background Art

[0002] Carrier-based aircraft are aircraft that take off from mobile ship platforms. In combat situations, the ability of carrier-based aircraft to take off quickly and reliably is a crucial technical requirement for ensuring their combat effectiveness. Unlike land-based takeoffs, the hull-attached decks and spoilers of mobile ship platforms complicate the aerodynamic environment for carrier-based aircraft. This is especially true during ski-jumps, when the engine is in afterburner mode and exhaust is obstructed by the spoilers. High-temperature exhaust gas can easily be drawn back into the engine, causing intake distortion, weakening the engine's stability margin, and adversely affecting the aircraft's safety. Therefore, suppressing intake distortion during ski-jumps is crucial to ensure the aircraft's safe operation.

[0003] However, although there are some solutions to suppress intake distortion in the existing technology, these solutions are all aimed at the flight process or ground test of aircraft engines. Currently, there is no solution to the unsteady intake distortion caused by the ski jump of carrier-based aircraft. Summary of the Invention

[0004] The purpose of the present application is to provide a system and method for suppressing intake distortion during a ski-jump of a carrier-based aircraft, so as to solve or alleviate at least one problem in the background technology.

[0005] The technical solution of the present application is: an intake distortion suppression system for a carrier aircraft during a ski-jump, comprising:

[0006] jet injection ports are provided on the decks on both sides of the initial position of the carrier aircraft, wherein the air jets flowing out of the jet injection ports are directed below the auxiliary air intake valve of the carrier aircraft;

[0007] High-pressure gas tanks located in deck tanks; and

[0008] A connecting pipeline connecting the jet injection port and the high-pressure gas tank, wherein a control valve is provided on the connecting pipeline;

[0009] During a ski-jump takeoff of a carrier aircraft, a jet airflow directed toward below the auxiliary air intake valve is ejected through the jet injection port. The jet airflow can suppress the backflow of exhaust gas at the belly of the carrier aircraft induced by a large-scale backflow area at the belly of the carrier aircraft, thereby reducing the engine intake temperature distortion caused by the backflow of high-temperature exhaust gas bleed from the baffle at the rear of the carrier aircraft and then being inhaled into the engine.

[0010] In a preferred embodiment of the present application, the distance between the jet injection port and the baffle is set to 2.5m to 5m, and the angle between the axis of the jet injection port and the flight trajectory is 15° to 60°.

[0011] In a preferred embodiment of the present application, the mass flow rate of the gas ejected from the jet injection port is 1 kg / s to 3.5 kg / s, the speed is 15 m / s to 45 m / s, and the jet injection duration is 0.1 s to 2 s.

[0012] In a preferred embodiment of the present application, an electric cover is further included, which blocks the jet injection port. When a carrier-based aircraft takes off by ski jump, the electric cover opens to expose the jet injection port. When no carrier-based aircraft takes off by ski jump, the electric cover closes to hide the jet injection port.

[0013] On the other hand, the technical solution provided by the present application is: a method for suppressing intake distortion using any of the above-described intake distortion suppression systems for a carrier aircraft during a ski-jump, comprising:

[0014] Before a carrier-based aircraft takes off from a ski jump, a predetermined pulse frequency is used to control the jet nozzle to eject airflow;

[0015] When the carrier aircraft starts, the pulse jet of the jet nozzle is controlled to be changed to continuous jet. During the carrier aircraft's ski-jump takeoff, the jet nozzle's jet direction is always pointed below the carrier aircraft's auxiliary air intake valve. The jet airflow suppresses the backflow of exhaust gas induced by the large-scale backflow area at the carrier aircraft's belly, eliminating the high-temperature exhaust gas flowing into the auxiliary air intake valve.

[0016] The mass flow rate of the jet gas flowing from the high-pressure gas tank to the jet injection port is adjusted by a control valve, so that the high-temperature backflow of the carrier-based aircraft during the ski-jump process is always suppressed.

[0017] In a preferred embodiment of the present application, the predetermined pulse frequency is 10 Hz to 50 Hz.

[0018] The intake distortion control system and method for the ski-jump process of carrier-based aircraft in the present application adopts jet injection of fresh air, which can, on the one hand, suppress the backflow of high-temperature exhaust gas and reduce the engine intake distortion. The jet injected by the low-temperature jet is sucked into the engine through the auxiliary intake valve, and the gas flow entering the engine is increased. On the other hand, the flow and frequency of the pulse jet are in a modulatable state, which can save the gas source flow and reduce the power of the high-pressure air pump. The system is installed under the deck and has no impact on the flight activities of the aircraft carrier. It has high efficiency, small size and simple control. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions provided by this application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this application.

[0020] Figure 1This is a schematic diagram of the layout of a carrier-based aircraft using the intake distortion suppression system of the present application.

[0021] Figure 2 Schematic diagram of the intake distortion suppression system of this application.

[0022] Figure 3 Schematic diagram of the flow field near the belly of a carrier-based aircraft when there is no intake distortion suppression system.

[0023] Figure 4 Schematic diagram of the flow field near the belly of a carrier-based aircraft when the intake distortion suppression system is in place.

[0024] Figure 5 Schematic diagram of real-time matching of jet flow control and carrier-based aircraft speed.

[0025] Reference numerals:

[0026] 1-Deck

[0027] 2-Baffle

[0028] 3-Intake distortion suppression system, 31-Jet injection port, 32-Connecting pipe, 33-Control valve, 34-High-pressure gas tank

[0029] 4-carrier aircraft, 41-engine inlet, 42-auxiliary air intake valve

[0030] 5-Recirculating exhaust gas

[0031] 6-Large-scale reflux zone DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0033] In order to overcome the problem that the intake distortion suppression scheme in the existing technology is difficult to solve the backflow of high-temperature exhaust gas during the ski-jump of the carrier-based aircraft, resulting in the high-temperature exhaust gas being sucked in by the auxiliary intake valve, and then causing the intake distortion problem of the engine during the ski-jump of the carrier-based aircraft, the present application proposes an intake distortion suppression system based on pulse jet injection control, which is used to suppress the unsteady intake distortion of the engine during the ski-jump of the carrier-based aircraft.

[0034] like Figure 1 and Figure 2As shown, a carrier aircraft 4 is located on the deck 1 of a mobile ship platform, with a baffle 2 positioned at its rear. During a ski-jump takeoff, the baffle 2 is raised, causing the aircraft 4 to inhale high-temperature exhaust gas from its engine, resulting in induced air intake distortion. To this end, the present application provides a system for suppressing intake distortion during a ski-jump for carrier aircraft based on pulse jet control technology. The system 3 includes a jet injection port 31, a connecting pipe 32, a control valve 33, and a high-pressure gas tank 34. The jet injection port 31 is positioned on the deck 1 on both sides of the initial position of the carrier aircraft 4. The high-pressure gas tank 34 can be located in the deck compartment. The jet injection port 31 is connected to the high-pressure gas tank 34 via a connecting pipe 32 and a control valve 33.

[0035] In some embodiments of the present application, the distance between the jet injection port 31 and the baffle 2 is typically set at 2.5 to 5 meters, and the angle between the axis of the jet injection port 31 and the flight trajectory is 15 to 60 degrees. The gas mass flow rate flowing out of the jet injection port 31 is 1 kg / s to 3.5 kg / s, the velocity is 15 to 45 m / s, and the jet injection duration is 0.1 to 2 seconds. Furthermore, the gas jet flowing out of the jet injection port 31 is directed below the auxiliary air intake valve 42 of the carrier aircraft 4.

[0036] In some embodiments of the present application, the jet injection port 31 can be shielded by an electric cover, which can be set on the outside of the deck 1 or on the inside of the deck 1. When a carrier-based aircraft 4 takes off by ski jump, the electric cover opens to expose the jet injection port 31. When no carrier-based aircraft 4 takes off by ski jump, the electric cover closes and the jet injection port 31 is hidden, thereby not affecting other functions of the deck 1.

[0037] like Figure 3 The figure shows the flow field near the belly of a carrier aircraft without an intake distortion suppression system. When the carrier aircraft 4 is ski-jumping, it is blocked by the deflector 2. The high-temperature exhaust gas from the tail nozzle of the carrier aircraft 4 flows back and is drawn into the engine, causing temperature distortion of the engine intake air. The intake air temperature rise comes from the high-temperature gas drawn in through the intake ducts on both sides of the engine and from the auxiliary intake valve 42 under the aircraft belly. The intake air from the auxiliary intake valve 42 accounts for the largest proportion.

[0038] like Figure 4 The flow field diagram near the belly of the carrier-based aircraft with the intake distortion suppression system shown in the figure is as follows: Figure 5The diagram below illustrates the real-time matching of jet flow control with aircraft speed. Before aircraft 4 ski-jumps, a pulsed jet flow with an operating frequency of 10Hz to 50Hz is used. At the moment aircraft 4 starts, the pulsed jet becomes a continuous jet, and the jet direction is always directed downward from the auxiliary air intake valve 42 during aircraft 4's movement. This suppresses the backflow of exhaust gas 5 induced by the large-scale backflow area 6 at the belly of the aircraft. This ensures that "fresh" air, rather than high-temperature "exhaust gas" from the engine inlet 41, flows into the auxiliary air intake valve 42. A control valve 33 regulates the mass of the outflowing gas from the high-pressure gas tank 34 to the jet injection port 31, ensuring that high-temperature backflow is consistently suppressed during the aircraft 4's ski-jump.

[0039] Compared with the prior art, the intake distortion control system and method for the ski-jump process of carrier-based aircraft in the present application adopts jet injection of fresh air, which can, on the one hand, suppress the backflow of high-temperature exhaust gas and reduce the engine intake distortion. The jet injected by the low-temperature jet is sucked into the engine through the auxiliary intake valve, and the gas flow entering the engine is increased. On the other hand, the flow and frequency of the pulse jet are in a modulatable state, which can save the gas source flow and reduce the power of the high-pressure air pump. The system is installed under the deck and has no impact on the flight activities of the aircraft carrier. It has high efficiency, small size and simple control.

[0040] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. An air intake distortion suppression system for a carrier aircraft during a ski jump, characterized in that: include: jet injection ports are provided on the decks on both sides of the initial position of the carrier aircraft, wherein the air jets flowing out of the jet injection ports are directed below the auxiliary air intake valve of the carrier aircraft; High-pressure gas tanks installed in deck tanks; as well as A connecting pipeline connecting the jet injection port and the high-pressure gas tank, wherein a control valve is provided on the connecting pipeline; During a ski-jump takeoff of a carrier aircraft, a jet airflow directed toward below the auxiliary air intake valve is ejected through the jet injection port. The jet airflow can suppress the backflow of exhaust gas at the belly of the carrier aircraft induced by a large-scale backflow area at the belly of the carrier aircraft, thereby reducing the engine intake temperature distortion caused by the backflow of high-temperature exhaust gas bleed from the baffle at the rear of the carrier aircraft and then being inhaled into the engine.

2. The air intake distortion suppression system for a carrier aircraft during a ski jump according to claim 1, wherein: The distance between the jet injection port and the baffle is set to 2.5m-5m, and the angle between the axis of the jet injection port and the flight trajectory is 15°-60°.

3. The air intake distortion suppression system for a carrier aircraft during a ski jump according to claim 2, wherein: The mass flow rate of the gas ejected from the jet injection port is 1 kg / s to 3.5 kg / s, the speed is 15 m / s to 45 m / s, and the jet injection duration is 0.1 s to 2 s.

4. The air intake distortion suppression system for a carrier aircraft during a ski jump according to claim 1, wherein: It also includes an electric cover that blocks the jet injection port. When a carrier-based aircraft takes off by ski jump, the electric cover opens to expose the jet injection port. When no carrier-based aircraft takes off by ski jump, the electric cover closes to hide the jet injection port.

5. A method for suppressing intake distortion using the intake distortion suppression system for a carrier aircraft ski-jump process according to any one of claims 1 to 4, characterized in that: include: Before a carrier-based aircraft takes off from a ski jump, a predetermined pulse frequency is used to control the jet nozzle to eject airflow; When the carrier aircraft starts, the pulse jet of the jet nozzle is controlled to be changed to continuous jet. During the carrier aircraft's ski-jump takeoff, the jet nozzle's jet direction is always pointed below the carrier aircraft's auxiliary air intake valve. The jet airflow suppresses the backflow of exhaust gas induced by the large-scale backflow area at the carrier aircraft's belly, eliminating the high-temperature exhaust gas flowing into the auxiliary air intake valve. The mass flow rate of the jet gas flowing from the high-pressure gas tank to the jet injection port is adjusted by a control valve, so that the high-temperature backflow of the carrier-based aircraft during the ski-jump process is always suppressed.

6. The method according to claim 5, wherein The predetermined pulse frequency is 10 Hz to 50 Hz.

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