Three-dimensional rotating isentropic compression inlet structure

Abstract

The patent of the present invention discloses a three-dimensional rotating isentropic compression inlet structure, which specifically relates to the field of supersonic aircraft power technology. It includes a first-stage axisymmetric compression section, a second-stage axisymmetric compression section and an outer wall shell. The first-stage axisymmetric compression section and the second-stage axisymmetric compression section are connected to form a rotating structure of an isentropic compression inlet; the outer wall shell adopts a specific spatial curve layout design, and the outer wall shell alone constitutes the outer flow channel stator structure of the entire inlet. The technical solution of the present invention solves the problems of low compression efficiency, complex structure, heavy weight, high process difficulty and inconvenient operation of the existing inlet, and can meet the needs of adaptive control of inlet flow and a wider and higher working Mach number.

Description

Technical Field

[0001] The invention relates to the technical field of supersonic aircraft power, and in particular to a three-dimensional rotating isentropic compression type air inlet structure. Background Art

[0002] As the requirements for weapon maneuverability in high-speed and rapid attack targets become increasingly higher, the high-quality and rapid development of supersonic aircraft power plants is promoted; among them, the air inlet, as an important component of the supersonic aircraft power plant, has the function of capturing the free incoming flow and decelerating and pressurizing it, providing the required flow field to the engine. Therefore, the performance of the air inlet directly determines the working performance of the engine, and its design technology is one of the key technologies of the supersonic aircraft power plant.

[0003] The existing supersonic inlet is mainly designed in two sections, the front section uses a shock wave system to compress the airflow, and the rear section uses a subsonic expansion section design, which leads to a large overall airflow loss and low compression efficiency; at the same time, the traditional supersonic inlet generally adopts a geometrically adjustable axisymmetric structure, and the throat geometry is controlled by moving the center cone to adjust the size of the flow entering the inlet, thereby controlling the Mach number of the inlet throat. However, this type of inlet has low compression efficiency, complex structure, heavy weight, high process difficulty, and inconvenient operation. It is not suitable for aircraft power devices with simple structural requirements, high aerodynamic performance requirements, and light weight requirements. Therefore, designing an inlet structure with high compression efficiency, simple configuration, high reliability, and adaptive flow control to achieve better aerodynamic performance of the inlet in a wider Mach number range has become a bottleneck technology that supersonic aircraft power urgently needs to solve. Summary of the invention

[0004] The present invention aims to provide a three-dimensional rotating isentropic compression inlet structure, which solves the problems of low compression efficiency, complex structure, heavy weight, high process difficulty and inconvenient operation of the existing inlet.

[0005] In order to achieve the above-mentioned purpose, the technical scheme of the present invention is as follows: a three-dimensional rotating isentropic compression inlet structure, comprising a first-level axisymmetric compression section, a second-level axisymmetric compression section and an outer wall shell, wherein the first-level axisymmetric compression section and the second-level axisymmetric compression section are connected to form a rotating structure of the isentropic compression inlet; the outer wall shell adopts a specific spatial curve layout design, and the outer wall shell alone constitutes the outer flow duct stator structure of the entire inlet.

[0006] Furthermore, the first-level axisymmetric compression section is composed of an axisymmetric conical isentropic compression curved surface body and a circumferential anti-rotation hole arranged on the curved surface body; the second-level axisymmetric compression section is composed of an axisymmetric conical isentropic compression extension section, a first circumferential positioning hole and a rotational torque transmission spline, the isentropic compression curved surface body and the isentropic compression extension section are connected into one by a first positioning block and a second positioning block, the circumferential anti-rotation hole and the first circumferential positioning hole are positioned and connected by a pin shaft, and the rotational torque transmission spline is connected to the driver.

[0007] Furthermore, the outer wall shell consists of a lip cover and a second circumferential positioning hole, the outer surface of the lip cover forms an angle of 7° with the axis, and the inner surface of the lip cover adopts a quadratic curve structure; the rear section of the lip cover is arranged with a surface suction hole; the outer wall shell is positioned and constrained with the upper-level parts through the second circumferential positioning hole.

[0008] Compared with the prior art, this solution has the following beneficial effects:

[0009] 1. The three-dimensional rotating isentropic compression inlet has high compression efficiency, simple configuration, simple operation, and adaptive adjustable flow rate, which can meet the requirements of supersonic aircraft power for the aerodynamic performance and structural strength of the inlet.

[0010] 2. According to the evaluation example of the performance function and structural strength of a supersonic aircraft power unit, this three-dimensional rotating isentropic compression inlet effectively reduces flow loss and improves compression capacity, meets the requirements of adaptive control of inlet flow and a wider and higher working Mach number, and therefore has great engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is an axonometric view of the three-dimensional rotating isentropic compression inlet structure of the present invention;

[0012] Figure 2 is a cross-sectional view of the three-dimensional rotating isentropic compression inlet structure of the present invention;

[0013] Figure 3 is a cross-sectional view of the first-stage axisymmetric compression section in this embodiment;

[0014] Figure 4 is a side view of the first-stage axisymmetric compression section in this embodiment;

[0015] Figure 5 is a cross-sectional view of the secondary axisymmetric compression section in this embodiment;

[0016] Figure 6 is a side view of the secondary axisymmetric compression section of this embodiment;

[0017] Figure 7 is a side view of the outer wall shell in this embodiment;

[0018] Figure 8 It is a cross-sectional view of the outer wall shell in this embodiment. DETAILED DESCRIPTION

[0019] The present invention is further described in detail below through specific embodiments:

[0020] The figure marks in the drawings of the specification include: a first-level axisymmetric compression section 1, a second-level axisymmetric compression section 2, an outer wall shell 3, 4, a circumferential anti-rotation hole 5, a first circumferential positioning hole 6, a rotary torque transmission spline 7, a first positioning block 8, a second positioning block 9, a lip cover 10, a second circumferential positioning hole 11, and a suction hole 12.

[0021] Example

[0022] As attached Figures 1 to 8 As shown: a three-dimensional rotating isentropic compression inlet structure, including a first-level axisymmetric compression section 1, a second-level axisymmetric compression section 2 and an outer wall shell 3, the first-level axisymmetric compression section 1 and the second-level axisymmetric compression section 2 are integrated through a specific assembly surface and axial and circumferential positioning, and form a rotating structure of the isentropic compression inlet. The first-level axisymmetric compression section 1 is composed of an axisymmetric conical isentropic compression curved surface body and a circumferential anti-rotation hole 5 set on the curved surface body; the second-level axisymmetric compression section 2 is composed of an axisymmetric conical isentropic compression extension section, a first circumferential positioning hole 6 and a rotating torque transmission spline 7, the isentropic compression curved surface body and the isentropic compression extension section are connected into one by a first positioning block 8 and a second positioning block 9, thereby forming a rotating structure of the inlet, the circumferential anti-rotation hole 5 and the first circumferential positioning hole 6 are positioned and connected by a pin shaft, and the rotating torque transmission spline 7 is connected to the driver; this scheme relies on end face friction to transmit torque and contact limit; the entire inlet rotating structure is connected to the driver through a rectangular spline to achieve the purpose of torque transmission.

[0023] The outer wall shell 3 adopts a specific spatial curve layout design, and the outer wall shell 3 alone constitutes the outer flow channel stator structure of the entire inlet. The outer wall shell 3 consists of a lip cover 10 and a second circumferential positioning hole 11. The outer surface of the lip cover 10 forms an angle of 7° with the axis of the lip cover 10, and the inner surface of the lip cover 10 adopts a quadratic curve structure to achieve flow capture capability within a wide Mach number range; the rear section of the lip cover 10 is arranged with a boundary suction hole 12 to suck the boundary layer on the inner surface under a large Mach number to avoid flow separation; the outer wall shell 3 is positioned and constrained with the upper part through the second circumferential positioning hole 11.

[0024] The design method of this scheme specifically includes the following steps:

[0025] Step 1: Based on isentropic compression wave compression, design the inlet compression section profile curve and the lip cover 10 profile curve that meet the hypersonic compression capacity and compression efficiency;

[0026] Step 2: Based on the profile curves of the compression section and the lip cover 10 obtained in step 1, combined with the spatial geometric constraints, structural functional requirements and the requirement that the strength rupture reserve coefficient ≮1.25, a spatial geometric structure scheme of the air intake is designed and laid out.

[0027] Step 3: Based on the intake duct structure scheme of step 2, design the detailed structure of the three-dimensional rotating isentropic compression intake duct. First, design the structure of the first-stage axisymmetric compression section 1. The compression surface line is determined by step 1. It is only necessary to reduce the mass as much as possible to improve the working stability on the basis of meeting the strength reserve. Therefore, the cavity streamline design method is adopted. The rear end face is designed with three first positioning blocks 8 with an angle of 120° to each other, a thickness of 3.4mm, a height of 4.4mm, and a length of 3.6mm. They are used for end face friction torque transmission and axial and circumferential limitation. These geometric parameters are determined through strength verification cycle iteration.

[0028] Step 4: Next, design the structure of the secondary axisymmetric compression section 2. The profile of the compression extension section is determined by step 1. The structural function requires that the front end and the end face of the primary axisymmetric compression section 1 are frictionally transmitted and positioned, and the rear end is positioned and transmitted with the mechanical interface of the upper driver. At the same time, the center must be radially coordinated with the rotating shaft for centering. Therefore, the front end face is designed as 3 second positioning blocks 9 and 3 first circumferential positioning holes 6, and the rear end face is designed as 6 rotating torque transmission torque-shaped splines 7 that are 60° apart, 6.0mm wide and 5.0mm deep.

[0029] Step 5: Then design the structure of the outer wall shell 3, whose inner surface profile is determined by step 1, and the outer surface forms an angle of 7° with the axis. At the same time, two rows of φ2.0mm boundary suction holes 12 are arranged at the rear section of the lip cover 10 to suck the boundary layer on the inner surface of the lip cover 10 at a large Mach number to avoid flow separation. The entire outer wall shell 3 is positioned and constrained with the upper part through the second circumferential positioning hole 11.

[0030] The above are only embodiments of the present invention, and the common knowledge such as the known specific structures and / or characteristics in the scheme are not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A three-dimensional rotating isentropic compression inlet structure, characterized by: It comprises a first-stage axisymmetric compression section, a second-stage axisymmetric compression section and an outer wall shell, wherein the first-stage axisymmetric compression section and the second-stage axisymmetric compression section are connected to form a rotating structure of an isentropic compression inlet; the outer wall shell adopts a cavity streamlined design, and the outer wall shell alone constitutes an outer flow channel stator structure of the entire inlet; The first-level axisymmetric compression section is composed of an axisymmetric conical isentropic compression curved surface body and a circumferential anti-rotation hole arranged on the curved surface body; the second-level axisymmetric compression section is composed of an axisymmetric conical isentropic compression extension section, a first circumferential positioning hole and a rotational torque transmission spline, the isentropic compression curved surface body and the isentropic compression extension section are connected into one piece by a first positioning block and a second positioning block, the circumferential anti-rotation hole and the first circumferential positioning hole are positioned and connected by a pin shaft, and the rotational torque transmission spline is connected to the driver.

2. The three-dimensional rotating isentropic compression inlet structure according to claim 1, characterized in that: The outer wall shell consists of a lip cover and a second circumferential positioning hole. The outer surface of the lip cover forms an angle of 7° with the axis, and the inner surface of the lip cover adopts a quadratic curve structure; the rear section of the lip cover is arranged with a surface suction hole; the outer wall shell is positioned and constrained with the upper-level parts through the second circumferential positioning hole.

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