CN113153531B - A variable overflow tank adjustment mechanism, scramjet engine and hypersonic aircraft - Google Patents

Abstract

The invention discloses a variable overflow groove adjusting mechanism, a scramjet engine and a hypersonic aircraft, which are suitable for the air inlet of the wide-speed range aircraft. The variable overflow groove mechanism comprises an adjusting plate and an adjusting mechanism; The bottom of the adjusting plate is provided with a plurality of adjusting plugs, and the adjusting plugs are inserted into the overflow groove of the scramjet; the adjusting mechanism is connected with the adjusting plate and is used to drive the adjusting plate to overflow relatively The launder moves to change the size of the overflow slot opening. Compared with the method of using the variable structure of the front body/upper inlet port surface and the traditional method of using the overflow groove with fixed opening size, it can effectively reduce the starting Mach number and adjust the air quality entering the combustion chamber. The adjustment range of this structure is large. , the structure is simple, the quality is small, the engineering application is highly achievable, and it is easy to realize.

Description

A variable overflow tank adjustment mechanism, scramjet engine and hypersonic aircraft

technical field

The invention relates to the technical field of aircraft air inlet design, in particular to a variable overflow groove adjusting mechanism, a scramjet engine and a hypersonic aircraft.

Background technique

The main types of hypersonic vehicles include reusable vehicles and hypersonic missiles. At present, hypersonic vehicles cannot take off directly from the ground only by relying on scramjets, and other power devices must be combined at low Mach numbers. Therefore, combined power such as rocket-based combined cycle or turbine-based combined cycle is often used. Rocket engine at low speed Or the turbine engine works, after accelerating the aircraft to a certain speed, the scramjet engine starts to work. The starting Mach number of the intake port not only affects the realization of the combined power, but also determines the proportion of the auxiliary propulsion force in the entire propulsion system at low Mach number, thus affecting the cost of hypersonic flight. Therefore, it is of great practical significance to study how to effectively reduce the starting Mach number of the hypersonic inlet.

At present, the methods adopted by the intake port to reduce the starting Mach number mainly include the method of variable geometry or the addition of overflow grooves. Liu Xiaowei from Northwestern Polytechnical University published the paper "Research on a Variable Geometry Scheme of RBCC Binary Inlet", which introduces a variable geometry structure, which discharges the low-velocity fluid in the boundary layer into the inlet by controlling the rotation of the compression plate of the inlet. airway, thereby reducing the start-up Mach number of the airway. Wang Weixing from Nanjing University of Aeronautics and Astronautics published the paper "Influence of Suction Position on Starting Performance of Hypersonic Inlet", which studied the influence of the position of the overflow groove on the Mach number of the intake port. Both of these two methods fix the starting Mach number of the intake port in a certain state, which cannot be adjusted independently according to different requirements, nor can the suction removal of the overflow groove be based on the thickness of the boundary layer in different flight states. quantity is controlled.

Therefore, it is necessary to provide a new type of mechanism with variable overflow groove size, which can not only absorb the boundary layer, reduce the shock wave/boundary layer interference, suppress the development and separation of the boundary layer of the intake port, increase the The effective throat area and the overflow groove for the intake port to start smoothly at a lower Mach number are generally used. Furthermore, the starting Mach number of the intake port can be controlled as required, and the overflow groove can be removed according to the flight state. Suction volume is controlled.

SUMMARY OF THE INVENTION

The invention provides a variable overflow groove adjusting mechanism, a scramjet engine and a hypersonic aircraft, and a variable overflow groove adjusting mechanism for a hypersonic air inlet, which is an adjusting mechanism that can control the starting Mach number of the air inlet, and is used for Controls the starting Mach number of the intake. When the intake port does not start at different flight Mach numbers, the flow rate of the low-pressure airflow at the transition between the throat and the compression surface is different. This structure can control the amount of suction and removal flow, so as to control the starting Mach number of the intake port to a certain value. In the range.

In order to achieve the above objects, the present invention provides the following technical solutions.

A variable overflow tank adjustment mechanism, comprising an adjustment plate and an adjustment mechanism;

The regulating plate has a bottom of the regulating plate, and the bottom of the regulating plate is provided with a plurality of regulating plugs, and the regulating plugs are inserted into the overflow groove of the scramjet;

The adjusting mechanism is connected with the adjusting plate, and is used for driving the adjusting plate to move relative to the overflow groove so as to change the size of the opening of the overflow groove.

As a further improvement of the present invention, the adjustment mechanism includes a rack block, a drive unit and a rack and pinion mechanism;

One end of the regulating plate is provided with a driven gear, and the other end is provided with a rear rack of the regulating plate;

A limit rack is arranged on the rack block, and the driven gear meshes with the limit rack;

The driving unit is provided with a driving gear that meshes with the rear rack of the adjusting plate, and the driving unit drives the driving gear to rotate.

As a further improvement of the present invention, the adjustment mechanism includes a rack block, a drive unit and a rack and pinion mechanism;

One end of the adjustment plate has a limit rack, and the other end has a rear rack of the adjustment plate;

A driven gear is arranged on the rack block, and the driven gear meshes with the limit rack;

The driving unit is provided with a driving gear that meshes with the rear rack of the adjusting plate, and the driving unit drives the driving gear to rotate.

As a further improvement of the present invention, the drive unit includes a motor base, a stepping motor and a reducer, the stepping motor is mounted on the motor base, and the stepping motor drives the driving gear through the reducer.

As a further improvement of the present invention, the size of the adjusting plug matches the overflow groove.

As a further improvement of the present invention, the curved surface corresponding to the bottom of the adjusting plate matches the curved surface of the transition surface where the overflow groove is located; the rack block and the drive unit are installed on the transition surface, and the adjusting plate is arranged on the rack block and the transition surface. between the drive units.

As a further improvement of the present invention, the overflow groove is an inverted trapezoidal groove; the mounting surface of the limit rack, the surface where the axes of the two driven gears are located, the AC surface of the adjustment plug, the BD surface of the overflow groove, The mounting surfaces of the racks behind the adjusting plate are parallel to each other.

As a further improvement of the present invention, in the intake passage with the variable overflow groove adjustment mechanism, at least two of the rack block, the rear rack of the adjustment plate, and the driving gear meshing with the rear rack of the adjustment plate are provided, and all are provided with at least two. Symmetrical positions on both sides of the adjusting plate; at least two driven gears should be provided on each side, and the two sides are also in symmetrical positions on the adjusting plate.

A scramjet engine, comprising an intake port, the intake port includes a three-stage precursor compression surface, a throat surface, an engine bottom plate and an engine expansion section connected in sequence, wherein the three-stage precursor compression surface and the throat surface A transition surface is formed therebetween, and the overflow groove is arranged on the transition surface; the transition surface is provided with the variable overflow groove adjustment mechanism.

A hypersonic aircraft includes an aircraft fuselage and the scramjet engine.

Compared with the prior art, the present invention has the following beneficial effects:

The invention discloses a variable overflow groove mechanism suitable for the air inlet of an aircraft in a wide speed range. composition. The opening size of the overflow groove can be changed by adjusting the plate to control the thickness of the boundary layer at the connection between the air inlet compression surface and the throat of the hypersonic vehicle, so as to realize the adjustment of the starting Mach number of the air inlet, which can improve the intake air at different Mach numbers. It can improve the airflow quality, take into account the aerodynamic performance under different Mach numbers, obtain higher engine performance, smooth transition of different modes, and lower mass penalty. Compared with the method of using the variable structure of the front body/upper inlet port surface and the traditional method of using the overflow groove with fixed opening size, it can effectively reduce the starting Mach number and adjust the air quality entering the combustion chamber. The adjustment range of this structure is large. , the structure is simple, the quality is small, the engineering application is highly achievable, and it is easy to realize.

Further, the upper air inlet is connected with the aircraft front body and the air inlet throat respectively at the front and rear, and is the main bearing part of the adjusting mechanism. The adjustment plate is the key part of the structure, controlling its up and down translation, the size of the opening of the overflow groove can be easily adjusted, so as to control the amount of suction flow. The motor is the power source of the structure, the motor transmits the force to the driving gear through the reducer, and drives the adjustment plate to move by means of the rack and pinion transmission.

The invention controls the thickness of the boundary layer at the connection between the compression surface of the air inlet and the throat of the hypersonic aircraft, so as to realize the adjustment of the starting Mach number of the air inlet and the control of the suction removal amount of the overflow groove. Compared with the reduction of the starting Mach number by means of a variable structure, the structure has a larger adjustment range, a simple structure, a smaller mass, and is easy to implement.

Description of drawings

The drawings described herein are for explanatory purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes and proportions of the components in the figures are only schematic and are used to help the understanding of the present invention, and do not specifically limit the shapes and proportions of the components of the present invention. Under the teachings of the present invention, those skilled in the art can select various possible shapes and proportions according to specific conditions to implement the present invention. In the attached image:

Figure 1 is a diagram showing the installation position of a scramjet in a typical hypersonic vehicle.

Figure 2 is a cross-sectional view of a typical hypersonic vehicle.

Figure 3 is an axonometric view of the intake port self-starting structure.

Figure 4 is the front, right, top and bottom views of the air intake self-starting structure; (a) is a top view, (b) is a front view, (c) is a right view, and (d) is a bottom view.

FIG. 5 is an enlarged front view of the intake port self-starting structure.

Figure 6 is an enlarged view of the front part of the adjustment plate.

Figure 7 is a schematic diagram of the position of the adjustment plate at the highest point.

Fig. 8 is a cross-sectional view of the overflow groove when the adjusting plate is at the highest position.

The names of the parts corresponding to each label in the figure are as follows: 1. Aircraft fuselage; 2. Scramjet; 3. First-stage compression surface; 4. Second-stage compression surface; 5. Third-stage compression surface; 6. Transition 7. Throat surface; 8. Engine bottom plate; 9. Engine expansion section; 10. Rack block; 11. Adjusting plate; 12. Adjusting plate rear rack; 13. Gear key; 14. Rotating shaft; 15. Active Gear; 16. Reducer; 17. Stepper motor; 18. Limit rack; 19. Driven gear; 20. Overflow groove; 21. Bottom of adjustment plate; 22. Adjustment plug.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be cleared and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for the purpose of illustration only and do not represent the only embodiment.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used herein in the description of the present invention are for the purpose of describing specific embodiments only, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in FIG. 1 and FIG. 2 , in a hypersonic aircraft, the scramjet engine 2 is installed on the abdomen of the hypersonic aircraft fuselage 1 , and the engine structure and the aircraft fuselage 1 have a high degree of integration.

The intake port of the scramjet engine 2 is mainly composed of a three-stage precursor compression surface (composed of a first-stage compression surface 3, a second-stage compression surface 4, and a third-stage compression surface 5), a throat surface 7, and an engine bottom plate 8. , The engine expansion section 9 is composed of four parts, among which the three-stage precursor compression surface is also used as a part of the aircraft fuselage to bear the aerodynamic load. During flight, a separation zone occurs at the transition of the compression-facing throat segment, and the lower the Mach number, the larger the separation zone. When the separation zone is too large, the airflow gets blocked at the inlet and cannot enter the combustion chamber, causing the engine to fail. Therefore, adding openings in the area of the throat section close to the separation zone can suck out the low-pressure airflow, reduce the area of the separation zone, and allow the airflow to circulate normally.

As shown in FIGS. 3 to 6 , specifically, the present invention provides a variable overflow tank adjustment mechanism, including an adjustment plate 11 and an adjustment mechanism; the adjustment plate 11 has an adjustment plate bottom 21 , and the adjustment plate bottom is provided with a A plurality of adjusting plugs 22, the adjusting plugs 22 are inserted into the overflow groove 20 of the scramjet engine 2; the adjusting mechanism is connected with the adjusting plate 11 for driving the adjusting plate 11 to move relative to the overflow groove 20 Further, the size of the opening of the overflow groove 20 is changed. Specifically, the adjusting plate moves linearly, and the adjusting plug 22 and the overflow groove 20 slide relative to each other.

The adjustment mechanism includes a rack block 10, a drive unit and a rack and pinion mechanism; one end of the adjustment plate 11 has a driven gear 19, and the other end has an adjustment plate rear rack 12; the rack block 10 is provided with The limit rack 18 meshed with the driven gear 19 is provided with a driving gear 15 meshed with the rear rack 12 of the adjusting plate on the driving unit, and the driving unit drives the driving gear 15 to rotate.

The described embodiments are only some, but not all, embodiments of the present invention. To achieve the same purpose, the limiting rack 18 can also be arranged on the front end of the adjusting plate 11 , and the driven gear 19 can be arranged on the rack block 10 .

In a preferred embodiment, the driving unit includes a motor base, a stepping motor 17 and a reducer 16 , the stepping motor 17 is mounted on the motor base, and the stepping motor 17 drives the driving gear through the reducer 16 . The input shaft of the stepping motor 17 is inserted into the input hole of the worm gear reducer 16 and fixed with a key to prevent circumferential rotation. The gear 15 is inserted into the shaft 14 through the shaft hole and fixed with a key to prevent circumferential rotation. The power provided by the stepping motor 17 drives the rotating shaft 14 to rotate after passing through the reducer 16, thereby driving the driving gear 15 to rotate, and the driving gear 15 meshes with the rear rack 12 of the adjusting plate for transmission, so that the rotational motion of the gear is converted into a translational motion of the rack. Thereby, the adjusting plate 11 on which the rack is fixed is driven to perform translation in the fixed direction. The front end of the adjusting plate is equipped with a driven gear 19 that can rotate freely up and down, which ensures the straight up and down movement of the adjusting plate 11 by engaging with the rack 18 on the rack block 10 .

Preferably, the size of the adjustment plug 22 is matched to the size of the overflow groove 20 . When the adjusting plate moves to the bottom, the adjusting plug 22 and the overflow groove 20 are completely closed and sealed, and the double mechanical cooperation does not require other sealing structures.

The curved surface corresponding to the bottom 21 of the adjusting plate matches the curved surface of the transition surface 6 where the overflow groove 20 is located; the rack block 10 and the drive unit are both installed on the transition surface 6, and the adjusting plate 11 is arranged on the rack block 10 and the between the drive units. The overflow groove 20 is an inverted trapezoidal groove; the installation surface of the limit rack 18, the surface where the axes of the two driven gears 19 are located, the AC surface of the adjustment plug 22, the BD surface of the overflow groove 20, and the adjustment plate The mounting surfaces of the rear racks 12 are parallel to each other.

In order to ensure that the movement of the adjustment plate maintains a stable linear motion, each air inlet has a variable overflow groove adjustment mechanism, the rack block 10 , the rear rack 12 of the adjustment plate, and the driving gear meshing with the rear rack 12 of the adjustment plate There are at least two gears 15 , and they are arranged at symmetrical positions on both sides of the adjustment plate 11 ; at least two driven gears 19 should be arranged on each side, and the two sides are also at the symmetrical positions of the adjustment plate 11 .

As shown in Figure 7, the Mach number when the scramjet starts to work is called the starting Mach number. The lower the starting Mach number, the larger the working range of the engine. When the flight speed has not reached the starting Mach number, the compression of the intake port will create a large separation area at the transition of the throat, so that the airflow cannot pass through. At this time, the control system drives the adjustment plate to move upward by starting the stepper motor, and discharges the low-speed boundary layer airflow collected at the entrance of the throat, so that the intake port can be started. Because the thickness of the boundary layer and the size of the separation zone are different at different speeds, the airflow that needs to be sucked out is different. By controlling the speed and number of turns of the stepping motor, and controlling the movement of the adjusting plate, it is convenient to control The size of the opening of the overflow groove can control the suction and removal flow and control the starting Mach number within a certain range, so that the engine can be started in a wider speed range.

As shown in Figure 8, the airflow enters the variable overflow slot from the DE of the upper air intake transition zone, flows out from the HI, and then flows out through the flow channel of the HJKL to the overflow slot opening on the side wall of the aircraft. Wherein, the regulating plug 22 of the regulating plate 11 can be simplified as the quadrilateral ACFJ, which is all equal to the simplified quadrilateral BIED of the overflow groove in the transition area of the upper air intake. Make an auxiliary line FG through point F and perpendicular to point G, and make auxiliary line FE, and the angle of ∠FEI is α. It should be noted that since the minimum channel width of the outlet air flow of the overflow groove of the variable overflow groove mechanism is FG, and there is a Pythagorean theorem, it can be known that: FG=FE·sinα, where FE=CD, is the moving distance of the adjusting plug 22, Therefore, ∠FEI should not be too small, because this will cause the opening of the real overflow tank to be too small, and the actual suction removal effect will decrease.

The present invention is a variable overflow groove mechanism suitable for the air inlet of a wide-speed range aircraft. The upper air inlet is connected with the aircraft front body and the inlet throat respectively at the front and rear, and is the main bearing part of the adjusting mechanism. The adjustment plate is the key part of the structure, controlling its up and down translation, the size of the opening of the overflow groove can be easily adjusted, so as to control the amount of suction flow. The motor is the power source of the structure, the motor transmits the force to the gear through the reducer, and drives the adjustment plate to move by means of the rack and pinion transmission.

The control of the mechanism of the present invention requires the following preparations:

According to the computational fluid dynamics (CFD) analysis in the overall design stage of the aircraft, the thickness of the boundary layer of the aircraft at different flight altitudes and flight Mach numbers is determined, thereby determining the size of the suction removal and the required adjustment height of the adjustment plate. Furthermore, the control system can interpolate and determine the required air flow quality of the intake port and the thickness of the boundary layer according to the flight conditions of the aircraft, and control and adjust the height of the adjustment plate through the motor, reducer, and rack and pinion structure, that is, control the overflow The size of the slot opening.

The opening size of the overflow groove can be changed by adjusting the plate to control the thickness of the boundary layer at the connection between the air inlet compression surface and the throat of the hypersonic vehicle, so as to realize the adjustment of the starting Mach number of the air inlet, which can improve the intake air at different Mach numbers. It can improve the airflow quality, take into account the aerodynamic performance under different Mach numbers, obtain higher engine performance, smooth transition of different modes, and lower mass penalty.

The invention controls the thickness of the boundary layer at the connection between the compression surface of the air inlet and the throat of the hypersonic aircraft, so as to realize the adjustment of the starting Mach number of the air inlet and the control of the suction removal amount of the overflow groove. Compared with the method of using the variable structure of the front body/upper inlet port surface and the traditional method of using the overflow groove with fixed opening size, it can effectively reduce the starting Mach number and adjust the air quality entering the combustion chamber. The adjustment range of this structure is large. , the structure is simple, the quality is small, the engineering application is highly achievable, and it is easy to realize.

It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for the purpose of description and to distinguish similar objects, and there is no sequence between the two, nor can they be construed as indicating or imply relative importance. Also, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

It should be understood that the above description is for purposes of illustration and not limitation. From reading the above description, many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the preceding claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated herein by reference for the purpose of being comprehensive. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to disclaim such subject matter, nor should the applicant be considered as not considering such subject matter as part of the disclosed subject matter.

Claims (7)

1. A variable overflow tank adjustment mechanism, characterized in that it comprises an adjustment plate (11) and an adjustment mechanism; The regulating plate (11) has a regulating plate bottom (21), the regulating plate bottom (21) is provided with a plurality of regulating plugs (22), and the regulating plugs (22) are inserted into the overflow of the scramjet (2). In the flow groove (20), the adjustment plug (22) matches the size of the overflow groove (20); The adjusting mechanism is connected with the adjusting plate (11), and is used for driving the adjusting plate (11) to move relative to the overflow groove (20) so as to change the size of the opening of the overflow groove (20); The adjusting mechanism includes a rack block (10), a drive unit and a rack and pinion mechanism; One end of the regulating plate (11) is provided with a driven gear (19), and the other end is provided with a rear gear rack (12) of the regulating plate; A limit rack (18) is arranged on the rack block (10), and the driven gear (19) meshes with the limit rack (18); The driving unit is provided with a driving gear (15) meshing with the rear rack (12) of the adjusting plate, and the driving unit drives the driving gear (15) to rotate; The curved surface corresponding to the bottom (21) of the adjusting plate matches the curved surface of the transition surface (6) where the overflow groove (20) is located; the rack block (10) and the drive unit are both mounted on the transition surface (6), The adjusting plate (11) is arranged between the rack block (10) and the drive unit. 2. A variable overflow tank adjustment mechanism, characterized in that it comprises an adjustment plate (11) and an adjustment mechanism; The regulating plate (11) has a regulating plate bottom (21), the regulating plate bottom (21) is provided with a plurality of regulating plugs (22), and the regulating plugs (22) are inserted into the overflow of the scramjet (2). In the flow groove (20), the adjustment plug (22) matches the size of the overflow groove (20); The adjusting mechanism is connected with the adjusting plate (11), and is used for driving the adjusting plate (11) to move relative to the overflow groove (20) so as to change the size of the opening of the overflow groove (20); The adjusting mechanism includes a rack block (10), a drive unit and a rack and pinion mechanism; One end of the adjusting plate (11) is provided with a limit rack (18), and the other end is provided with a rear adjusting plate rack (12); A driven gear (19) is arranged on the rack block (10), and the driven gear (19) meshes with the limit rack (18); The driving unit is provided with a driving gear (15) meshing with the rear rack (12) of the adjusting plate, and the driving unit drives the driving gear (15) to rotate; The curved surface corresponding to the bottom (21) of the adjusting plate matches the curved surface of the transition surface (6) where the overflow groove (20) is located; the rack block (10) and the drive unit are both mounted on the transition surface (6), The adjusting plate (11) is arranged between the rack block (10) and the drive unit. 3. A variable overflow tank adjusting mechanism according to claim 1 or 2, wherein the drive unit comprises a motor base, a stepping motor (17) and a reducer (16), the stepping motor (17) is installed on the motor base, and the stepping motor (17) drives the driving gear through the reducer (16). 4. A variable overflow groove adjustment mechanism according to claim 1 or 2, wherein the overflow groove (20) is an inverted trapezoidal groove; the mounting surface of the limit rack (18), The surfaces of the axes of the two driven gears (19), the AC surface of the adjusting plug (22), the BD surface of the overflow groove (20), and the mounting surface of the rear rack (12) of the adjusting plate are parallel to each other. 5. A variable overflow groove adjustment mechanism according to claim 1 or 2, characterized in that, in the air inlet with the variable overflow groove adjustment mechanism, the rack block (10), the rear rack of the adjustment plate (12) There are at least two driving gears (15) meshing with the rear rack (12) of the adjusting plate, and they are all arranged at symmetrical positions on both sides of the adjusting plate (11); the driven gears (19) each At least two sides should be provided, and the two sides should also be located at the symmetrical positions of the adjusting plate (11). 6. A scramjet engine, characterized in that it comprises an air inlet, and the air inlet comprises a three-stage precursor compression surface, a throat surface (7), an engine bottom plate (8) and an engine expansion section connected in sequence (9), wherein a transition surface (6) is formed between the tertiary precursor compression surface and the throat surface (7), and the overflow groove (20) is arranged on the transition surface (6); the transition surface (6) is arranged There is a variable overflow tank adjustment mechanism according to any one of claims 1 to 5. 7. A hypersonic aircraft, characterized in that it comprises an aircraft fuselage (1) and the scramjet engine (2) according to claim 6.

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