Unilateral expansion nozzle based on hydrogen injection and ejection

Abstract

The invention provides a single-side expansion spray pipe based on hydrogen injection and ejection, and belongs to the technical field of hypersonic aircraft spray pipes, the single-side expansion spray pipe comprises an ejection channel and a main flow channel, the two sides of the ejection channel are provided with fixed wall surfaces, ejection channel wall surfaces and an ejection adjusting plate movably connected with the ejection channel wall surfaces, the injection adjusting plate is located at the front end of the wall face of the injection channel in the airflow direction, a convergence section wall face and an expansion section wall face which are fixedly connected are arranged on one side of the main flow channel, the expansion section wall face is further fixedly connected with the front end of the wall face of the injection channel, and a convergence adjusting plate and an expansion adjusting plate which are movably connected are arranged on the other side of the main flow channel. The convergence section wall surface and the convergence adjusting plate are oppositely arranged to form a main flow channel convergence section, and the expansion section wall surface and the expansion adjusting plate are oppositely arranged to form a main flow channel expansion section; a hydrogen injection hole is formed in the position, close to the throat, of the convergence section and located in the wall face of the convergence section. By means of the treatment scheme, the effect of relieving over-expansion can be achieved, and the performance of the single-side expansion spray pipe is improved.

Description

Technical Field

[0001] The present application relates to the technical field of hypersonic aircraft nozzles, and in particular to a unilateral expansion nozzle based on hydrogen injection and ejection. Background Art

[0002] The nozzle is the exhaust device of an aircraft engine. The high-temperature combustion gas expands and does work in the nozzle, generating thrust.

[0003] For hypersonic aircraft, the flight envelope is wide, requiring the aircraft / propulsion system / tail nozzle to be designed in an integrated manner. The unilateral expansion nozzle directly uses the lower surface of the aircraft's rear body as the external expansion surface, which can meet the requirements of working under pressure drop ratios of hundreds or thousands, and achieve an area expansion ratio of dozens. Because of its integration with the aircraft, it can effectively reduce the rear body resistance. It has been verified in the US X-43 and X-51 hypersonic drones. However, the unilateral expansion nozzle is in a serious over-expansion state when it is not at the design point, and even flow separation may occur. Accompanied by the interaction of complex phenomena such as shock waves, expansion waves, and shock wave boundary layer interference, the performance is seriously reduced, and it may cause drastic changes in the thrust and lift of the nozzle. Summary of the invention

[0004] In view of this, an embodiment of the present application provides a single-sided expansion nozzle based on hydrogen injection, which at least partially solves the problem in the prior art that the single-sided expansion nozzle is in a serious over-expansion state when not in the design point state, resulting in a serious degradation of the nozzle performance.

[0005] The embodiment of the present application provides a unilateral expansion nozzle based on hydrogen injection and ejection, comprising an ejection channel and a mainstream channel, wherein fixed walls, ejection channel walls and ejection adjustment plates movably connected to the ejection channel walls are provided on both sides of the ejection channel, the ejection adjustment plate is located at the front end of the ejection channel wall along the airflow direction, one side of the mainstream channel is provided with a fixedly connected convergent section wall and an expansion section wall, the expansion section wall is also fixedly connected to the front end of the ejection channel wall along the airflow direction, the other side of the mainstream channel is provided with a movably connected convergent adjustment plate and an expansion adjustment plate, the convergent section wall and the convergent adjustment plate are arranged opposite to each other and constitute the convergent section of the mainstream channel, the expansion section wall and the expansion adjustment plate are arranged opposite to each other and constitute the expansion section of the mainstream channel; a hydrogen injection hole for injecting hydrogen into the throat of the mainstream channel is provided near the throat of the convergent section, and the hydrogen injection hole is located on the convergent section wall.

[0006] According to a specific implementation of the embodiment of the present application, the central axis of the hydrogen injection hole is perpendicular to the horizontal plane of the wall of the convergent section.

[0007] According to a specific implementation of the embodiment of the present application, the ratio of the pressure of the hydrogen injected into the hydrogen injection hole to the ambient pressure is in the range of 1 to 2.

[0008] According to a specific implementation method of an embodiment of the present application, the nozzle also includes a driven mechanism and a driving mechanism, the driven mechanism includes a first driven mechanism, a second driven mechanism and a third driven mechanism, the driving mechanism includes a first driving mechanism, a second driving mechanism and a third driving mechanism, the convergence adjustment plate is connected to the first driven mechanism through a rotating pair, the expansion adjustment plate is connected to the second driven mechanism through a rotating pair, the ejection adjustment plate is connected to the third driven mechanism through a rotating pair, the first driven mechanism is connected to the first driving mechanism through a rotating pair, the second driven mechanism is connected to the second driving mechanism through a rotating pair, the third driven mechanism is connected to the third driving mechanism through a rotating pair, and the first driving mechanism, the second driving mechanism and the third driving mechanism are respectively connected to the fixed casing of the nozzle through a moving pair.

[0009] According to a specific implementation method of an embodiment of the present application, the angle adjustment range of the convergence adjustment plate is 0°~40°, the angle adjustment range of the expansion adjustment plate is 0°~30°, and the angle adjustment range of the ejection adjustment plate is 0°~20°.

[0010] According to a specific implementation method of an embodiment of the present application, when the nozzle is in a working state of a large area ratio, the first driving mechanism drives the first driven mechanism to extend outward, and the second driving mechanism drives the second driven mechanism to retract inward, and the convergence adjustment plate and the expansion adjustment plate rotate around the hinge point to reach a large area ratio state.

[0011] According to a specific implementation method of an embodiment of the present application, when the nozzle is in a working state of a small area ratio, the first driving mechanism drives the first driven mechanism to retract inward, and the second driving mechanism drives the second driven mechanism to extend outward, and the convergence adjustment plate and the expansion adjustment plate rotate around the hinge point to reach a small area ratio state.

[0012] According to a specific implementation method of the embodiment of the present application, when the nozzle is in the ejection open state, the third driving mechanism drives the third driven mechanism to extend outward, and the ejection adjustment plate rotates around the hinge point to reach the ejection channel open state.

[0013] According to a specific implementation method of an embodiment of the present application, when the nozzle is in a hydrogen injection state, in an ejection-on state, the flow rate of injected hydrogen is increased to limit the flow of the mainstream channel, reduce the pressure of the expansion section, and eject the secondary flow in the ejection channel through the pressure difference.

[0014] According to a specific implementation of the embodiment of the present application, a plurality of hydrogen injection holes are provided, and the plurality of hydrogen injection holes are evenly distributed on the wall surface of the convergent section along a direction perpendicular to the airflow.

[0015] Beneficial effects: The unilateral expansion nozzle based on hydrogen injection in the embodiment of the present application has an injection function added, and the secondary flow in the injection channel acts as an air cushion on the main flow path, restricting the expansion of the main flow. The injection adjustment plate is a movable connection, which can be rotated and adjusted relative to the wall of the injection channel, so as to achieve the flow regulation of the secondary flow in the injection channel. By adjusting the flow of the secondary flow, the flow area of ​​the main flow path can be controlled to achieve or approach full expansion, reduce thrust loss, and enable the aircraft to have good performance in a wider range. In addition, the hydrogen injection function is also added in this embodiment. The main flow is affected by hydrogen to change the throat area. At the same time, the secondary flow is injected through the pressure difference to achieve the effect of alleviating over-expansion, further improving the performance of the unilateral expansion nozzle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the mechanical structure of a unilateral expansion nozzle based on hydrogen injection and ejection according to an embodiment of the present invention; Figure 2 A schematic diagram of fluid flow in a single-side expansion nozzle based on hydrogen injection and ejection according to an embodiment of the present invention; Figure 3 A simplified diagram of the motion mechanism of a unilateral expansion nozzle based on hydrogen injection and ejection according to an embodiment of the present invention; Figure 4 Schematic diagram of a large area ratio state of a unilateral expansion nozzle based on hydrogen injection and ejection according to an embodiment of the present invention, (a) is a simplified diagram of the motion mechanism, and (b) is a mechanical structure diagram; Figure 5 Schematic diagram of a small area ratio state of a unilateral expansion nozzle based on hydrogen injection and ejection according to an embodiment of the present invention, (a) is a simplified diagram of the motion mechanism, and (b) is a mechanical structure diagram; Figure 6 The diagram is a schematic diagram of the injection opening state of a single-sided expansion nozzle based on hydrogen injection injection according to an embodiment of the present invention, (a) is a simplified diagram of the motion mechanism, and (b) is a mechanical structure diagram.

[0018] In the figure: 1. first driving mechanism; 2. first driven mechanism; 3. first actuator; 4. second driving mechanism; 5. second driven mechanism; 6. second actuator; 7. third driving mechanism; 8. third driven mechanism; 9. third actuator; 10. ejection adjustment plate; 11. fixed wall; 12. ejection channel wall; 13. convergence section wall; 14. hydrogen injection hole; 15. convergence adjustment plate; 16. expansion adjustment plate; 17. expansion section wall. DETAILED DESCRIPTION

[0019] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0020] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0021] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0022] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show the components related to the present application rather than being drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0023] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0024] The present application embodiment provides a unilateral expansion nozzle based on hydrogen injection and ejection, as shown below Figures 1 to 6 Describe in detail.

[0025] Reference Figure 1 The embodiment of the present application provides a unilateral expansion nozzle based on hydrogen injection and ejection, including an ejection channel and a mainstream channel. A fixed wall 11, an ejection channel wall 12 and an ejection adjustment plate 10 movably connected to the ejection channel wall 12 are provided on both sides of the ejection channel. The ejection adjustment plate 10 is located at the front end of the ejection channel wall 12 along the airflow direction. A fixedly connected convergent section wall 13 and an expansion section wall 17 are provided on one side of the mainstream channel. The expansion section wall 17 is also fixedly connected to the front end of the ejection channel wall 12 along the airflow direction. A movably connected convergent adjustment plate 15 and an expansion adjustment plate 16 are provided on the other side of the mainstream channel. The convergent section wall 13 and the convergent adjustment plate 15 are arranged oppositely and constitute the convergent section of the mainstream channel. The expansion section wall 17 and the expansion adjustment plate 16 are arranged oppositely and constitute the expansion section of the mainstream channel. A hydrogen injection hole 14 for injecting hydrogen into the throat of the mainstream channel is provided near the throat of the convergent section, and the hydrogen injection hole 14 is located on the convergent section wall 13.

[0026] Reference Figure 2 The unilateral expansion nozzle in this embodiment has an ejection function. The secondary flow in the ejection channel acts as an air cushion on the main flow path, restricting the expansion of the main flow. The ejection adjustment plate 10 is a movable connection and can be rotated and adjusted relative to the ejection channel wall 12, so as to achieve flow regulation of the secondary flow in the ejection channel. By adjusting the secondary flow flow, the flow area of ​​the main flow path can be controlled to achieve or approach full expansion, reduce thrust loss, and enable the aircraft to have good performance in a wider range. In addition, the hydrogen injection function is added in this embodiment. The main flow is affected by hydrogen to change the throat area. At the same time, the secondary flow is ejected by the pressure difference to achieve the effect of alleviating over-expansion, further improving the performance of the unilateral expansion nozzle.

[0027] In one embodiment, the central axis of the hydrogen injection hole 14 is perpendicular to the horizontal plane of the convergent section wall 13 .

[0028] In one embodiment, the ratio of the pressure of the hydrogen injected into the hydrogen injection hole 14 to the ambient pressure is in the range of 1-2.

[0029] In specific implementation, hydrogen is injected through a hole in the throat. The mainstream is affected by the hydrogen, causing the throat area to change. At the same time, the secondary flow is injected through the pressure difference to achieve the effect of alleviating overexpansion, thereby improving the nozzle performance.

[0030] In one embodiment, in order to adjust the physical throat area and control the opening and closing of the ejection channel, the nozzle further includes a driven mechanism and a driving mechanism. Figure 3 The driven mechanism includes a first driven mechanism 2, a second driven mechanism 5 and a third driven mechanism 8, the driving mechanism includes a first driving mechanism 1, a second driving mechanism 4 and a third driving mechanism 7, the convergence adjustment plate 15 is connected to the first driven mechanism 2 through a rotating pair, the expansion adjustment plate 16 is connected to the second driven mechanism 5 through a rotating pair, the ejection adjustment plate 10 is connected to the third driven mechanism 8 through a rotating pair, the first driven mechanism 2 is connected to the first driving mechanism 1 through a rotating pair, the second driven mechanism 5 is connected to the second driving mechanism 4 through a rotating pair, the third driven mechanism 8 is connected to the third driving mechanism 7 through a rotating pair, and the first driving mechanism 1, the second driving mechanism 4 and the third driving mechanism 7 are respectively connected to the fixed casing of the nozzle through a moving pair.

[0031] The schematic diagram of the motion mechanism of the unilateral expansion nozzle in this embodiment is as follows: Figure 3 As shown, its overall motion mode is a planar multi-link mechanism, wherein the first driving mechanism 1, the second driving mechanism 4 and the third driving mechanism 7 in the form of connecting rods are respectively connected to the fixed casing by a moving pair, and perform translational telescopic motion relative to the casing. The first follower mechanism 2, the second follower mechanism 5 and the third follower mechanism 8 in the form of connecting rods are respectively connected to the corresponding driving mechanism by a rotating pair at one end, and are respectively connected to the corresponding actuator by a rotating pair at the other end. Among them, the actuator includes the first actuator 3, the second actuator 6 and the third actuator 9, the first actuator 3 corresponds to the convergence adjustment plate 15, the second actuator 6 corresponds to the expansion adjustment plate 16, and the third actuator 9 corresponds to the ejection adjustment plate 10. The first actuator 3, the second actuator 6 and the third actuator 9 in the form of connecting rods are respectively connected to the corresponding follower mechanism by a rotating pair, so the motion mechanism contains 9 connecting rods in total.

[0032] The connecting rods are connected through revolving pairs, and the driving mechanism is connected to the casing through moving pairs. The planar multi-link mechanism has 9 revolving pairs and 3 moving pairs.

[0033] Through the above analysis, it can be concluded that the mechanism has 9 connecting rods and 12 low pairs (including 9 rotating pairs and 3 moving pairs), so the degree of freedom F of the mechanism is: F=3n-2PL=3*9-2*12=3, Among them, n is the number of connecting rods and PL is the number of low pairs.

[0034] Therefore, the number of degrees of freedom of the planar linkage mechanism is 3, which means that the mechanism needs 3 driving mechanisms to realize a certain form of motion, which is consistent with the number of driving mechanisms determined during the design, namely, the first driving mechanism 1, the second driving mechanism 4 and the third driving mechanism 7, a total of 3 connecting rods. This shows that the design of the mechanism is reasonable and reliable.

[0035] In one embodiment, the physical throat area is adjusted by the adjustment mechanism, the angle adjustment range of the convergence adjustment plate 15 is 0°~40°, and the angle adjustment range of the expansion adjustment plate 16 is 0°~30°. The ejection adjustment plate 10 controls the opening and closing of the ejection channel, and the angle adjustment range of the ejection adjustment plate 10 is 0°~20°.

[0036] The different working modes of the unilateral expansion nozzle based on hydrogen injection are described in detail below.

[0037] In one embodiment, referring to Figure 4 In (a) and (b), when the nozzle is in the working state of the large area ratio state, the first driving mechanism 1 drives the first driven mechanism 2 to extend outward, the second driving mechanism 4 drives the second driven mechanism 5 to retract inward, and the convergence adjustment plate 15 and the expansion adjustment plate 16 rotate around the hinge point to reach the large area ratio state.

[0038] In one embodiment, referring to Figure 5 In (a) and (b), when the nozzle is in the working state of the small area ratio state, the first driving mechanism 1 drives the first driven mechanism 2 to retract inward, the second driving mechanism 4 drives the second driven mechanism 5 to extend outward, and the convergence adjustment plate 15 and the expansion adjustment plate 16 rotate around the hinge point to reach the small area ratio state.

[0039] In one embodiment, referring to Figure 6 In (a) and (b), when the nozzle is in the ejection open state, the third driving mechanism 7 drives the third driven mechanism 8 to extend outward, and the ejection adjustment plate 10 rotates around the hinge point to reach the ejection channel open state.

[0040] In one embodiment, when the nozzle is in the hydrogen injection state, in the ejection open state, the flow rate of the injected hydrogen is increased to limit the flow of the mainstream channel, reduce the expansion section pressure, and eject the secondary flow in the ejection channel through the pressure difference.

[0041] In one embodiment, a plurality of hydrogen injection holes 14 are provided, and the plurality of hydrogen injection holes 14 are evenly distributed on the convergent section wall 13 along a direction perpendicular to the gas flow.

[0042] The embodiment provided by the present invention adds an ejection function, and the secondary flow in the ejection channel acts as an air cushion on the main flow path, thereby restricting the expansion of the main flow. The ejection adjustment plate 10 is a movable connection, and can be rotated and adjusted relative to the ejection channel wall 12, so as to achieve the flow regulation of the secondary flow in the ejection channel. By adjusting the secondary flow flow, the flow area of ​​the main flow path can be controlled to achieve or approach full expansion, reduce thrust loss, and enable the aircraft to have good performance in a wider range. In addition, the hydrogen injection function is also added in this embodiment. The main flow is affected by hydrogen to change the throat area. At the same time, the secondary flow is ejected by the pressure difference to achieve the effect of alleviating over-expansion, further improving the performance of the unilateral expansion nozzle.

[0043] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A unilateral expansion nozzle based on hydrogen injection, characterized in that: The invention comprises an ejection channel and a main flow channel, wherein fixed walls (11), ejection channel walls (12) and ejection adjustment plates (10) movably connected to the ejection channel walls (12) are provided on both sides of the ejection channel, the ejection adjustment plates (10) are located at the front end of the ejection channel walls (12) along the airflow direction, and a convergence section wall (13) and an expansion section wall (17) are fixedly connected to one side of the main flow channel, and the expansion section wall (17) is also fixedly connected to the front end of the ejection channel wall (12) along the airflow direction. A convergent adjustment plate (15) and an expansion adjustment plate (16) are movably connected to each other on the other side of the mainstream channel; the convergent section wall surface (13) and the convergent adjustment plate (15) are arranged relative to each other and constitute the convergent section of the mainstream channel; the expansion section wall surface (17) and the expansion adjustment plate (16) are arranged relative to each other and constitute the expansion section of the mainstream channel; a hydrogen injection hole (14) for injecting hydrogen into the throat of the mainstream channel is provided near the throat of the convergent section, and the hydrogen injection hole (14) is located on the convergent section wall surface (13).

2. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 1 is characterized in that: The central axis of the hydrogen injection hole (14) is perpendicular to the horizontal plane of the convergent section wall (13).

3. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 1 is characterized in that: The ratio of the pressure of the hydrogen gas injected into the hydrogen injection hole (14) to the ambient pressure is in the range of 1 to 2.

4. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 1 is characterized in that: The nozzle further comprises a driven mechanism and a driving mechanism, wherein the driven mechanism comprises a first driven mechanism (2), a second driven mechanism (5) and a third driven mechanism (8), and the driving mechanism comprises a first driving mechanism (1), a second driving mechanism (4) and a third driving mechanism (7). The convergence adjustment plate (15) is connected to the first driven mechanism (2) via a rotating pair, the expansion adjustment plate (16) is connected to the second driven mechanism (5) via a rotating pair, the ejection adjustment plate (10) is connected to the third driven mechanism (8) via a rotating pair, the first driven mechanism (2) is connected to the first driving mechanism (1) via a rotating pair, the second driven mechanism (5) is connected to the second driving mechanism (4) via a rotating pair, the third driven mechanism (8) is connected to the third driving mechanism (7) via a rotating pair, and the first driving mechanism (1), the second driving mechanism (4) and the third driving mechanism (7) are respectively connected to the fixed casing of the nozzle via a moving pair.

5. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 4 is characterized in that: The angle adjustment range of the convergence adjustment plate (15) is 0° to 40°, the angle adjustment range of the expansion adjustment plate (16) is 0° to 30°, and the angle adjustment range of the ejection adjustment plate (10) is 0° to 20°.

6. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 4 is characterized in that: When the nozzle is in a large area ratio state, the first drive mechanism (1) drives the first driven mechanism (2) to extend outward, the second drive mechanism (4) drives the second driven mechanism (5) to retract inward, and the convergence adjustment plate (15) and the expansion adjustment plate (16) rotate around the hinge point to achieve a large area ratio state.

7. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 4 is characterized in that: When the nozzle is in a working state of a small area ratio, the first driving mechanism (1) drives the first driven mechanism (2) to retract inward, the second driving mechanism (4) drives the second driven mechanism (5) to extend outward, and the convergence adjustment plate (15) and the expansion adjustment plate (16) rotate around the hinge point to achieve a small area ratio state.

8. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 4 is characterized in that: When the nozzle is in the ejection opening state, the third driving mechanism (7) drives the third driven mechanism (8) to extend outward, and the ejection adjustment plate (10) rotates around the hinge point to achieve the ejection channel opening state.

9. The unilateral expansion nozzle based on hydrogen injection and ejection according to claim 8, characterized in that: When the nozzle is in the hydrogen injection state, in the ejection opening state, the flow of the injected hydrogen is increased to limit the flow of the mainstream channel, reduce the expansion section pressure, and eject the secondary flow in the ejection channel through the pressure difference.

10. The unilateral expansion nozzle based on hydrogen injection and ejection according to any one of claims 1 to 9, characterized in that: A plurality of hydrogen injection holes (14) are provided, and the plurality of hydrogen injection holes (14) are evenly distributed on the wall surface (13) of the convergent section along a direction perpendicular to the gas flow.

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