A semi-external inlet structure for an aircraft

Abstract

The application discloses a semi-exposed air inlet channel structure for an aircraft, which comprises an air inlet channel flow channel, a flow regulation baffle and a fixed side plate; the air inlet channel flow channel is semi-exposed; the air inlet channel flow channel is a plane or a circular arc surface which is obliquely cut with the aircraft body; the flow regulation baffle is arranged on both sides of the air inlet channel flow channel and plays a flow regulating role; and the fixed side plate is installed on the outer side of the flow regulation baffle. The application improves the compactness of the structure of the aircraft, improves the performance of the air inlet channel and is simple to process.

Description

Technical Field

[0001] This invention belongs to the field of aircraft technology, specifically relating to a semi-exposed air intake structure for aircraft. Background Technology

[0002] Aircraft using turbine engines are generally designed with dedicated air intakes to provide the engine with air that meets the requirements for distortion, total pressure recovery coefficient, and flow rate.

[0003] Common air intakes for aircraft include exposed S-shaped air intakes and embedded air intakes. Exposed S-shaped air intakes are suitable for high subsonic and supersonic speeds, offering advantages such as a high total pressure recovery coefficient and low total pressure distortion at high speeds. However, their disadvantage is that the air intake is exposed outside the aircraft, resulting in poor stealth performance. Embedded air intakes are suitable for low subsonic speeds, offering good stealth performance. However, their disadvantage is that at medium and high subsonic speeds, total pressure loss and distortion are greater.

[0004] In 2007, Ma Jiangao of Nanjing University of Aeronautics and Astronautics described a design method for an S-curve air intake for unmanned aerial vehicles (UAVs). In 2015, Liu Lei optimized the S-curve air intake using ISIGHT software. In 2007, Sun Shu of Nanjing University of Aeronautics and Astronautics analyzed the working characteristics and flow field features of a buried air intake using numerical simulation. In 2020, Zeng Cheng of Nanjing University of Aeronautics and Astronautics designed and optimized a buried air intake with boundary layer suction.

[0005] Both exposed S-shaped air intakes and embedded air intakes incorporate a section of piping within the aircraft to guide airflow into the turbojet engine, suitable for structural designs where the engine is integrated into the aircraft. The advantages of these designs include improved airflow rectification, increased total pressure recovery coefficient, and reduced intake total pressure distortion.

[0006] The disadvantages of the above-mentioned air intake design are: 1) it is only suitable for a certain speed range; 2) the airflow duct occupies space in the aircraft; 3) the installation of the air intake and engine is complicated. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, this invention provides a semi-exposed air intake structure for aircraft, including an air intake channel, a flow-rectifying baffle, and fixed side plates. The air intake channel is semi-exposed; the air intake channel is a plane or arc surface obliquely cut to the aircraft fuselage; the flow-rectifying baffle is disposed on both sides of the air intake channel, serving a flow-rectifying function; the fixed side plates are installed on the outer side of the flow-rectifying baffle. This invention improves the structural compactness of the aircraft, enhances the performance of the air intake, and simplifies manufacturing.

[0008] The technical solution adopted by this invention to solve its technical problem is as follows: A semi-exposed air intake structure for an aircraft includes an air intake channel, a flow straightener, and a fixed side plate; The air intake channel is partially exposed; The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the fairing baffle, and the mounting surface of the turbojet engine. The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the flow divider, and the turbojet engine mounting surface of the turbojet engine inlet. The rectifier baffles are installed on both sides of the air intake channel to rectify the airflow. The fixed side plate is installed on the outside of the rectifier baffle.

[0009] Preferably, the interface between the air intake duct and the aircraft fuselage is an arc surface.

[0010] Preferably, the air intake duct is aerodynamically integrated with the aircraft fuselage design.

[0011] Preferably, the air intake duct can be machined separately or integrally machined with the aircraft fuselage section.

[0012] The beneficial effects of this invention are as follows: 1) Improved aircraft structural compactness. Because the aircraft's air intake is semi-exposed, compared to S-shaped or buried air intakes, under the same flight speed, altitude, angle of attack, sideslip angle, and total pressure recovery coefficient, the axial length of the air intake is significantly reduced. The semi-exposed mounting of the turbojet engine also reduces the overall size envelope. Furthermore, other aircraft components can be installed below the semi-exposed air intake and turbojet engine mounting surface, improving space utilization.

[0013] 2) Improved intake performance. Numerical simulation calculations show that, compared with S-curve intakes and embedded intakes, the intake of the present invention has a significantly expanded applicable range in terms of speed, angle of attack, and sideslip angle, and has better performance in terms of total pressure recovery coefficient and total pressure distortion index.

[0014] 3) The processing structure is simple and can be processed separately or integrated with the aircraft compartment. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention.

[0016] Figure 2 This is a half-sectional schematic diagram of the present invention.

[0017] Figure 3 This is a top view of the present invention.

[0018] In the diagram: 1-Aircraft fuselage, 2-Inlet duct, 3-Fluorescence divider, 4-Turbojet engine, 5-Fixed side plate, 6-Turbojet engine mounting surface. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] The technical problem that this invention aims to solve is to shorten the length of the aircraft's air intake, increase the range of the air intake's operating speed, angle of attack, and sideslip angle, and facilitate the installation of turbojet engines.

[0021] This invention provides a stable airflow to the turbojet engine by designing a semi-exposed air intake, which shortens the length of the aircraft, increases the operating speed, angle of attack, and sideslip angle range of the air intake, and significantly improves space utilization and reduces the outer envelope size of the aircraft by integrating it with the aircraft fuselage.

[0022] A semi-exposed air intake structure for aircraft includes an air intake channel, a flow straightener, and a fixed side plate.

[0023] The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the flow divider, and the turbojet engine mounting surface at the turbojet engine inlet, which also constitutes the air intake inlet surface. For turbojet engines of the same thrust level, the air capture area of ​​the air intake surface of this invention is much larger than that of traditional S-shaped air intakes or buried air intakes. Therefore, compared with S-shaped air intakes and buried air intakes, the air intake of this invention has a significantly expanded applicable range for speed, angle of attack, and sideslip angle, and exhibits better performance in terms of total pressure recovery coefficient and total pressure distortion index.

[0024] The specific dimensions of the plane or arc surface of the air intake flow channel, the arc surface of the interface between the air intake flow channel and the aircraft fuselage, and the shape of the fairing baffle are determined through simulation calculations.

[0025] To improve the space utilization of aircraft, when the turbojet engine is cylindrical, the turbojet engine mounting surface is generally also designed as a cylindrical surface, so that the turbojet engine and the turbojet engine mounting surface are as close and fixed as possible.

[0026] The air intake flow channel is integrated with the aerodynamic design of the aircraft fuselage. The air intake flow channel components can be machined separately or as part of the aircraft fuselage section.

[0027] The turbojet engine is fixed by the turbojet engine mounting surface and fixed side plate, and the outer envelope size of the aircraft is reduced.

[0028] Example: A semi-exposed air intake structure for an aircraft includes an air intake channel 2, a flow straightener 3, and a fixed side plate 5.

[0029] The semi-exposed air intake structure consists of the aircraft fuselage 1, the air intake channel 2, and the air rectifier 3, which realize the rectification of the air required by the engine under flight conditions.

[0030] The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the fairing baffle, and the turbojet engine mounting surface of the turbojet engine inlet.

[0031] The specific dimensions of the oblique plane or arc surface of the air intake flow channel 2, the arc surface of the interface between the air intake flow channel 2 and the aircraft fuselage 1, and the shape of the fairing baffle 3 are determined through simulation calculations.

[0032] The turbojet engine is fixed by the turbojet engine mounting surface 6 and the fixed side plate 5, and the outer contour envelope size of the aircraft is reduced.

[0033] To improve the space utilization of the aircraft, when the turbojet engine 4 is cylindrical, the turbojet engine mounting surface 6 is generally also designed as a cylindrical surface, so that the turbojet engine 4 and the turbojet engine mounting surface 6 are as close and fixed as possible.

Claims

1. A semi-exposed air intake structure for an aircraft, characterized in that, This includes the air intake channel, the flow straightener, and the fixed side plate; The air intake channel is partially exposed; The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the fairing baffle, and the mounting surface of the turbojet engine. The air intake duct is composed of the oblique plane of the aircraft fuselage, the arc surface of the flow divider, and the turbojet engine mounting surface of the turbojet engine inlet. The rectifier baffles are installed on both sides of the air intake channel to rectify the airflow. The fixed side plate is installed on the outside of the rectifier baffle.

2. The semi-exposed air intake structure for aircraft according to claim 1, characterized in that, The interface between the air intake duct and the aircraft fuselage is an arc surface.

3. The semi-exposed air intake structure for aircraft according to claim 1, characterized in that, The air intake flow channel is integrated with the aerodynamic design of the aircraft fuselage.

4. The semi-exposed air intake structure for aircraft according to claim 1, characterized in that, The air intake duct can be machined separately or integrated with the aircraft fuselage section.

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