A fluid-solid coupling experimental device for equal straight isolation section shock wave train and elastic wall

Abstract

The invention discloses a fluid-solid coupling experimental device for a straight isolation section shock wave train and an elastic wall plate, comprising an isolation section body, a cavity part and a back pressure part; the isolation section body is formed by connecting a front top plate, a rear top plate, a bottom plate and two side plates, the two side plates have observation windows, and the cavity part is connected between the front top plate and the rear top plate; the cavity part has a mounting platform, an elastic wall plate, a glass plate, an annular pad and a top cover, and the outer walls on both sides of the mounting platform have mounting pieces; the elastic wall plate is arranged on the lower end surface of the mounting platform; the pad and the glass plate are embedded in the mounting platform, and the top cover is arranged on the upper end surface of the mounting platform; the mounting piece presses the front and rear top plates, and the elastic wall plate is connected to the front and rear top plates; the mounting platform and the pad are both provided with air guide holes to communicate with each other; the back pressure part has two vertical plates, a motor seat connected to the two vertical plates, a linear motor arranged on the motor seat and a throttling cone connected to the linear motor, and the two vertical plates are connected to the two side plates. The device can study the aerodynamic elasticity of the isolation section wall plate under dynamic back pressure and its influence on the internal flow field structure and the isolation section performance.

Description

Technical Field

[0001] The invention belongs to the field of aerospace experimental technology, and in particular relates to a fluid-solid coupling experimental device for a shock wave train of an equal straight isolation section and an elastic wall plate. Background Art

[0002] The isolation section is an important component of the scramjet engine. It is located between the inlet and the combustion chamber. In addition to isolating the aerodynamic and thermal interference of the combustion chamber on the inlet, it can also coordinate the airflow between the inlet and the combustion chamber through a series of shock wave trains to achieve the deceleration and pressurization function of the supersonic flow. The isolation section is mostly a section of a straight rectangular straight tube or a slightly expanded circular tube with a straight cross section. Although the structure is simple, the internal flow state is extremely complex. Its flow characteristics are related to the starting characteristics of the scramjet engine inlet and the combustion characteristics of the combustion chamber. At present, hypersonic aircraft generally use thin-walled structures to reduce weight. Therefore, the fluid-solid coupling phenomenon between the shock wave train and the elastic wall structure is inevitable in the flow field in the isolation section. At the same time, due to the existence of combustion oscillation in the combustion chamber, the back pressure at the outlet of the isolation section will change dynamically, which will affect the aeroelastic response deformation of the isolation section wall and the flow field in the isolation section, affecting the overall performance of the isolation section. However, there are few experimental devices specifically studying the fluid-solid coupling between the shock wave train and the elastic wall in the straight isolation section under dynamic back pressure.

[0003] Therefore, it is necessary to design an experimental device for fluid-solid coupling of shock wave train and elastic wall panels in the isolation section to study the aeroelasticity of the inner wall panels of the equal straight isolation section under dynamic back pressure and its influence on the internal flow field structure and performance of the isolation section. Summary of the invention

[0004] In order to solve the problem in the prior art of lacking an experimental device specifically for studying the fluid-solid coupling between shock wave trains and elastic wall panels in an equal straight isolation section under dynamic back pressure, the present invention provides an experimental device for the fluid-solid coupling between shock wave trains and elastic wall panels in an equal straight isolation section.

[0005] The equal straight isolation section shock wave train and elastic wall plate fluid-solid coupling experimental device of the present invention comprises an isolation section body, a cavity portion installed on the top of the isolation section body, and a back pressure portion installed at the air outlet of the isolation section body;

[0006] The main body of the isolation section includes a top plate, a bottom plate and two side plates connected and surrounded, and glass observation windows are opened on the two side plates. The top plate is divided into a front top plate located on the air inlet side and a rear top plate located on the air outlet side, and the cavity part is connected between the front top plate and the rear top plate;

[0007] The cavity portion includes a mounting platform, an elastic wall plate, an annular pad, an optical glass plate and an annular top cover. The mounting platform uses a small rectangular ring and a large rectangular ring. The outer peripheral wall of the small rectangular ring matches the inner peripheral wall of the large rectangular ring. The upper side of the horizontal small rectangular ring is upwardly nested into the horizontal large rectangular ring and fixed to form a stepped support platform inside. A mounting piece is provided on the outer walls on both sides of the mounting platform; the elastic wall plate is installed on the lower end surface of the small rectangular ring for sealing; the pad is embedded in the large rectangular ring and supported by the support platform; the optical glass The plate is embedded in the large rectangular ring and supported by the pad; the top cover presses the optical glass plate and is fixed on the upper end surface of the large rectangular ring; a sealed cavity is formed between the optical glass plate and the elastic wall plate in the mounting platform; the mounting pieces on both sides respectively press and fix the front top plate and the rear top plate, and the two ends of the elastic wall plate are respectively connected to the front top plate and the rear top plate; a first air guide hole is horizontally penetrated on one side wall of the large rectangular ring, and a second air guide hole is horizontally penetrated on one side wall of the pad; the first air guide hole on the large rectangular ring corresponds to the second air guide hole on the inner pad and connects the sealed cavity with the outside;

[0008] The back-pressure part includes two vertical plates, a motor base connected to one end of the two vertical plates, a linear motor installed on the motor base and a throttling cone. The motor base has a through hole in the middle, and the ends of the two vertical plates away from the motor base are respectively connected to the ends of the two side plates located at the air outlet, and a horizontal slide groove is respectively provided on the two vertical plates; the throttling cone has an inclined upper slope and a lower slope, and the upper slope and the lower slope intersect to form a cone head, and the end away from the cone head is a cone tail, and a push-pull rod is fixed on the cone tail, and the push-pull rod passes through the through hole on the motor base and is connected to the linear motor; a slider is respectively provided on the two side surfaces of the throttling cone, and the two sliders are respectively inserted into the slide grooves on the two vertical plates and are slidably connected to the slide grooves; after the linear motor is started, the push-pull rod is pushed or pulled back, and the cone head of the throttling cone enters or exits between the rear top plate and the bottom plate accordingly.

[0009] Furthermore, a row of pressure measuring holes is provided on the bottom plate along the length direction, so that the flow changes of the internal flow field can be recorded by the pressure sensor, so as to obtain accurate experimental data.

[0010] Furthermore, the angle between the upper and lower slopes of the throttling cone is 14°-20°, and the cone head is chamfered. In this way, the airflow in the device can be made to flow out faster while effectively reducing the outlet cross-sectional area of ​​the isolation section.

[0011] Furthermore, the two opposite corners of the rear top plate and the bottom plate on the side of the back pressure portion are respectively set to a first inclined wedge and a second inclined wedge of 14°-20°, so as to correspond to the angle of the throttling cone and facilitate the passage of airflow.

[0012] Furthermore, a first mounting plate perpendicular to the front top plate is provided on the upper surface of the front top plate at the air inlet end of the isolation section body, and a second mounting plate perpendicular to the bottom plate is provided on the lower surface of the bottom plate, and mounting holes are provided on both the first mounting plate and the second mounting plate. In this way, it is convenient to install on other components.

[0013] Furthermore, the ratio of the thickness to the length of the elastic wall plate is 1:100-500. Such a ratio is conducive to clearly showing the vibration effect of the elastic wall plate.

[0014] Furthermore, the elastic wall plate is made of any one selected from stainless steel, aluminum alloy, titanium alloy, and C-SiC composite material, and the optical glass plate is a quartz glass plate. In this way, it is convenient to obtain materials.

[0015] Beneficial effects: The present invention consists of an isolation section body, a cavity section and a back pressure section, with a simplified structure and low cost, and is suitable for experimental research; by setting a cavity on the isolation section body and sealing it, during the experiment, the elastic wall plate can exhibit nonlinear deformation vibration due to the cavity above it, and the linear motor can drive the throttle cone of the back pressure section to move linearly, thereby changing the size of the isolation section outlet section and providing the back pressure required for the experiment. The experimental device can simulate the flow field flow in the real working environment of the scramjet isolation section, and provide a research basis for the fluid-solid coupling experiment of the shock wave train and the elastic wall plate in the isolation section under dynamic back pressure; by setting a glass observation window on the side panel of the isolation section, the flow changes of the internal flow field can be recorded by a high-speed schlieren camera system, which is convenient for obtaining accurate experimental data. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the experimental device of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure of the cavity part of the experimental device of the present invention;

[0018] Figure 3 It is a partial structural schematic diagram of the back pressure part of the experimental device of the present invention;

[0019] Figure 4 It is a schematic cross-sectional view of the front view of the experimental device of the present invention;

[0020] In the figure: 1. isolation section body; 11. front top plate; 111. first mounting plate; 12. rear top plate; 121. first inclined wedge; 13. side plate; 131. glass observation window; 14. bottom plate; 141. second mounting plate; 142. pressure measuring hole; 143. second inclined wedge; 2. cavity; 21. mounting platform; 211. small rectangular ring; 212. large rectangular ring; 213. mounting sheet; 214. first air guide hole; 22. elastic wall plate; 23. pad; 231. second air guide hole; 24. optical glass plate; 25. top cover; 26. sealed cavity; 3. backing pressure part; 31. vertical plate; 311. slide groove; 32. motor seat; 33. linear motor; 34. throttling cone; 341. slider; 342. push-pull rod; 343. upper inclined surface; 344. lower inclined surface. DETAILED DESCRIPTION

[0021] The present invention will now be further described in detail by way of embodiments in conjunction with the accompanying drawings, but the present invention is not limited to the embodiments.

[0022] like Figure 1 , Figure 4 As shown, the present invention is an experimental device for fluid-solid coupling of equal straight isolation section shock wave train and elastic wall plate, comprising an isolation section body 1, a cavity portion 2 installed on the top of the isolation section body 1 and a back pressure portion 3 installed at the air outlet of the isolation section body 1.

[0023] The main body 1 of the isolation section includes a top plate, a bottom plate 14 and two side plates 13 connected and surrounded. The two side plates 13 are provided with glass observation windows 131. The top plate is divided into a front top plate 11 located on the air inlet side and a rear top plate 12 located on the air outlet side. The cavity portion 2 is connected between the front top plate 11 and the rear top plate 12. Specifically, the two side plates 13 clamp and seal the two side walls of the front top plate 11, the cavity portion 2, the rear top plate 12 and the bottom plate 14. The two opposite corners of the rear top plate 12 and the bottom plate 14 on the side of the back pressure portion 3 are respectively set to a first inclined wedge 121 and a second inclined wedge 143 of 16 degrees; by setting the first inclined wedge 121 and the second inclined wedge 143, an expansion section can be formed at the air outlet of the isolation section main body 1 to accelerate the outflow of the supersonic airflow. At the air inlet end of the isolation section body 1, a first mounting plate 111 perpendicular to the front top plate 11 is provided on the upper surface of the front top plate 11, and a second mounting plate 141 perpendicular to the bottom plate 14 is provided on the lower surface of the bottom plate 14. Mounting holes are provided on both the first mounting plate 111 and the second mounting plate 141. A row of pressure measuring holes 142 penetrating vertically is provided on the bottom plate 14 along the length direction, and the spacing between two adjacent pressure measuring holes 142 is equal.

[0024] like Figure 2As shown, the cavity portion 2 includes a mounting platform 21, an elastic wall plate 22, a rectangular annular pad 23 (the rectangular ring in the text refers to a ring with a circle of inner circumferential walls and a circle of outer circumferential walls both being rectangular, and the long sides of the rectangle formed by the inner circumferential walls are parallel to the long sides of the rectangle formed by the outer circumferential walls, and correspondingly, the wide sides are also parallel), an optical glass plate 24 and a rectangular annular top cover 25.

[0025] The mounting platform 21 is formed by using a small rectangular ring 211 and a large rectangular ring 212. The outer peripheral wall of the small rectangular ring 211 matches the inner peripheral wall of the large rectangular ring 212. The upper side of the horizontal small rectangular ring 211 is inserted upward into the horizontal large rectangular ring 212 and fixed to form a stepped support platform inside. The outer side walls of the wide sides at the opposite ends of the large rectangular ring 212 are respectively provided with mounting pieces 213 protruding horizontally outward. The large rectangular ring 212, the small rectangular ring 211 and the mounting piece 213 are connected as an integral part, and the mounting piece 213 is provided with a mounting hole.

[0026] The length of the elastic wall panel 22 is equal to the length of the small rectangular ring 211, and the width of the elastic wall panel 22 is equal to the width of the small rectangular ring 211; a circle of through holes evenly distributed on the support ring surface are opened on the support, and a corresponding circle of screw holes are opened along the four sides of the upper surface of the elastic wall panel 22. Screws are passed through the through holes of the support and screwed into the screw holes of the elastic wall panel 22 to fix the elastic wall panel 22 on the lower end face of the small rectangular ring 211 and seal the lower end face; the ratio of the thickness to the length of the elastic wall panel 22 is 1:200.

[0027] The outer peripheral wall of the pad 23 and the outer peripheral wall of the optical glass plate 24 are used in conjunction with the inner peripheral wall of the large rectangular ring 212, the pad 23 is embedded in the large rectangular ring 212 and supported by the support platform; the optical glass plate 24 is embedded in the large rectangular ring 212 and supported by the pad 23; a circle of through holes evenly distributed on the ring surface and penetrating up and down are opened on the top cover 25, and a corresponding circle of screw holes are opened on the upper end surface of the large rectangular ring 212, the top cover 25 is pressed against the upper end surface of the optical glass plate 24 and the large rectangular ring 212, and screws are used to pass through the through holes on the top cover 25 and screw into the screw holes on the large rectangular ring 212 for fixing; a sealed cavity 26 is formed between the optical glass plate 24 and the elastic wall plate 22 in the mounting platform 21.

[0028] The mounting pieces 213 at both ends of the large rectangular ring 212 respectively press the front top plate 11 and the rear top plate 12, and screws are passed through the mounting holes on the mounting pieces 213 and screwed into the preset screw holes on the front top plate 11 and the rear top plate 12 to fix them. The outer side walls of the wide sides of the elastic wall plate 22 at both ends are connected to the rear side wall of the front top plate 11 and the front side wall of the rear top plate 12 respectively, and the outer side walls of the two opposite long sides of the elastic wall plate 22 are clamped by the two side plates 13 of the isolation section body 1; screw holes are provided on the two side walls of the front top plate 11, the rear top plate 12, the bottom plate 14, and the small rectangular ring 211, and the two side plates 13 of the isolation section body 1 are provided with a row of corresponding through holes in the upper and lower sides, and screws are passed through the through holes on the two side plates 13 of the isolation section body 1 and screwed into the screw holes to clamp and fix the front top plate 11, the rear top plate 12, the bottom plate 14, and the small rectangular ring 211.

[0029] A first air guide hole 214 is provided on the side wall of one long side of the large rectangular ring 212, and a second air guide hole 231 is provided on the side wall of one long side of the pad 23. The first air guide hole 214 on the large rectangular ring 212 corresponds to the second air guide hole 231 on the inner pad 23 and connects the sealed cavity 26 to the outside. The first air guide hole 214 can be connected to an external vacuum pump to adjust the pressure in the sealed cavity 26 to meet the required cavity pressure.

[0030] like Figure 3 As shown, the back pressure part 3 includes two vertical plates 31, a motor base 32 connected to one end of the two vertical plates 31, a linear motor 33 installed on the motor base 32, and a throttling cone 34; the middle part of the motor base 32 has a through hole, and the ends of the two vertical plates 31 away from the motor base 32 are respectively welded to the ends of the two side plates 13 of the isolation section body 1 located at the air outlet, or can be integrally formed, and a corresponding horizontal slide groove 311 is respectively opened on the two vertical plates 31; the ends of the two vertical plates 31 connected to the motor base 32 are both provided with through holes, and the two end surfaces of the motor base 32 are provided with screws, and screws are used to pass through the through holes on the two vertical plates 31 and screw into the screw holes on the motor base 32 for fastening; the throttling cone 34 has an inclined upper inclined surface 343 and a lower inclined surface 344, and the upper inclined surface 343 and the lower inclined surface 344 intersect A cone head with an angle of 16° is formed, and the cone head is chamfered, the inclined surface of the first inclined wedge 121 is parallel to the upper inclined surface 343 of the throttling cone 34, and the inclined surface of the second inclined wedge 143 is parallel to the lower inclined surface 344 of the throttling cone 34; the end away from the cone head is a cone tail, and a push-pull rod 342 perpendicular to the cone tail and horizontal is integrally formed on the cone tail, and the other end of the push-pull rod 342 passes through the through hole on the motor seat 32 and is connected to the linear motor 33; a slider 341 is respectively provided on the two side surfaces of the throttling cone 34, and the two sliders 341 are respectively inserted into the slide grooves 311 on the two vertical plates 31 and are slidably connected to the slide grooves 311; after the linear motor 33 is started, the push-pull rod 342 is pushed or pulled back, and the cone head of the throttling cone 34 enters or exits between the rear top plate 12 and the bottom plate 14.

[0031] The optical glass plate 24 is a quartz glass plate; in addition, the cavity portion 2, the isolation section body 1, the two vertical plates 31 of the back pressure portion 3, the throttling cone 34 and the motor base 32 are all made of aluminum alloy.

[0032] The above-mentioned technologies not specifically mentioned are all referred to the prior art.

[0033] Based on the above-mentioned ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above-mentioned description. The technical scope of the present invention is not limited to the contents of the specification.

Claims

1. An experimental device for fluid-solid coupling between a straight isolation section shock wave train and an elastic wall plate, It is characterized in that It comprises an isolation section body (1), a cavity portion (2) installed at the top of the isolation section body (1), and a back pressure portion (3) installed at the air outlet of the isolation section body (1); The isolation section body (1) comprises a top plate, a bottom plate (14) and two side plates (13) connected and surrounded, the two side plates (13) are provided with glass observation windows (131), the top plate is divided into a front top plate (11) located on the air inlet side and a rear top plate (12) located on the air outlet side, and the cavity portion (2) is connected between the front top plate (11) and the rear top plate (12); The cavity portion (2) comprises a mounting platform (21), an elastic wall plate (22), an annular pad (23), an optical glass plate (24) and an annular top cover (25). The mounting platform (21) comprises a small rectangular ring (211) and a large rectangular ring (212). The outer peripheral wall of the small rectangular ring (211) matches the inner peripheral wall of the large rectangular ring (212). The upper side of the horizontal small rectangular ring (211) is upwardly embedded into the horizontal large rectangular ring (212) and fixed to form a stepped support platform inside. A mounting piece (213) is provided on the outer walls of the mounting platform (21) on both sides of the opposite sides. The elastic wall plate (22) is mounted on the lower end surface of the small rectangular ring (211) to be sealed. The pad (23) is embedded in the large rectangular ring (212) and supported by the support platform. The optical glass plate (24) is embedded in the large rectangular ring. (212) and supported by a pad (23); a top cover (25) presses the optical glass plate (24) and is fixed to the upper end surface of the large rectangular ring (212); a sealed cavity (26) is formed between the optical glass plate (24) and the elastic wall plate (22) in the mounting platform (21); the mounting pieces (213) on both sides respectively press the front top plate (11) and the rear top plate (12) and fix them, and the two ends of the elastic wall plate (22) are respectively connected to the front top plate (11) and the rear top plate (12); a first air guide hole (214) is horizontally penetrated on one side wall of the large rectangular ring (212), and a second air guide hole (231) is horizontally penetrated on one side wall of the pad (23); the first air guide hole (214) on the large rectangular ring (212) and the second air guide hole (231) on the inner pad (23) correspond to each other and connect the sealed cavity (26) with the outside; The back pressure portion (3) comprises two vertical plates (31), a motor base (32) connected to one end of the two vertical plates (31), a linear motor (33) mounted on the motor base (32), and a throttling cone (34); a through hole is provided in the middle of the motor base (32); one end of the two vertical plates (31) away from the motor base (32) is respectively connected to one end of the two side plates (13) located at the air outlet; a horizontal slide groove (311) is respectively provided on the two vertical plates (31); the throttling cone (34) has an inclined upper slope (343) and a lower slope (344); the upper slope (343) and the lower slope (344) are respectively provided with an inclined surface. The two ends intersect to form a cone head, and the end away from the cone head is a cone tail. A push-pull rod (342) is fixed on the cone tail, and the push-pull rod (342) passes through the through hole on the motor base (32) and is connected to the linear motor (33); a slider (341) is provided on each side of the throttling cone (34), and the two sliders (341) are respectively inserted into the slide grooves (311) on the two vertical plates (31) and are slidably connected to the slide grooves (311); after the linear motor (33) is started, the push-pull rod (342) is pushed or pulled back, and the cone head of the throttling cone (34) enters or exits between the rear top plate (12) and the bottom plate (14).

2. According to the equal straight isolation section shock wave train and elastic wall plate fluid-solid coupling experimental device of claim 1, It is characterized in that A row of pressure measuring holes (142) penetrating vertically is provided on the bottom plate (14) along the length direction.

3. According to the equal straight isolation section shock wave train and elastic wall plate fluid-solid coupling experimental device of claim 2, It is characterized in that The included angle between the upper inclined surface (343) and the lower inclined surface (344) of the throttling cone (34) is 14°-20°, and the cone head is chamfered.

4. According to the equal straight isolation section shock wave train and elastic wall plate fluid-solid coupling experimental device of claim 3, It is characterized in that Two opposite corners of the rear top plate (12) and the bottom plate (14) located on the side of the counter-pressure portion (3) are respectively arranged to form a first inclined wedge (121) and a second inclined wedge (143) with an angle of 14°-20°.

5. According to the equal straight isolation section shock wave train and elastic wall plate fluid-solid coupling experimental device of claim 4, It is characterized in that A first mounting plate (111) perpendicular to the front top plate (11) is provided on the upper surface of the front top plate (11) at the air inlet end of the isolation section body (1), and a second mounting plate (141) perpendicular to the bottom plate (14) is provided on the lower surface of the bottom plate (14), and mounting holes are provided on both the first mounting plate (111) and the second mounting plate (141).

6. The fluid-solid coupling experimental device of equal straight isolation section shock wave train and elastic wall plate according to claim 5, It is characterized in that The ratio of the thickness to the length of the elastic wall plate (22) is 1:100-500.

7. The fluid-solid coupling experimental device of equal straight isolation section shock wave train and elastic wall plate according to claim 6, It is characterized in that The elastic wall plate (22) is made of any one selected from stainless steel, aluminum alloy, titanium alloy, and C-SiC composite material, and the optical glass plate (24) is a quartz glass plate.

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