Inter-stage section of air-breathing aircraft with drainage function

Abstract

The invention discloses an interstage section of an air-breathing aircraft with a drainage function, and aims to solve the problems of relatively large airflow resistance in a boosting stage, complex structure and inconvenience in separation in a traditional aircraft. The interstage section comprises an interstage section front section, an interstage section rear section, a plurality of connecting arms and a separation assembly, the interstage section front section is connected with the interstage section rear section through the connecting arms, and a drainage channel is formed among the connecting arms; the front section of the interstage section is connected with the tail end of the upper stage, an inlet of the drainage channel is formed in the front section of the interstage section, the inlet of the drainage channel corresponds to the position of the exhaust nozzle of the upper stage, and the rear section of the interstage section is connected with the booster; and the front section of the interstage section is connected with the tail end of the upper stage through a separation assembly. The drainage channel directly communicated with the upper stage exhaust nozzle is formed in the interstage section, the drainage channel directly corresponds to the position of the exhaust nozzle, a low-resistance exhaust path is provided for fuel gas in an engine, and pressure disturbance caused by retention of airflow in the interstage section is avoided.

Description

Technical Field

[0001] This invention relates to the field of hypersonic vehicle structural design, and more particularly to an interstage section of an air-breathing vehicle with a flow-out function. Background Technology

[0002] Hypersonic vehicles powered by ramjet engines or detonation engines need to compress the inlet airflow through ramjet, so there are certain requirements for the speed and altitude of the vehicle. In application, they mostly use a tandem rocket booster to enter the design flight window. The key structural component connecting the upper stage vehicle and the rocket booster is generally defined as the interstage section.

[0003] During the boost phase, the ramjet engine of the upper-stage air-breathing aircraft is not operational. With the engine intake open and the nozzle closed, a blind cavity forms within the aircraft's internal flow channels, causing airflow stagnation within the engine. This can generate significant drag and aerodynamic / thermal loads, potentially leading to the intake failing to activate and inducing low-frequency shock wave oscillations. Without intervention, this would severely reduce the reliability of the cruise aircraft. To prevent the intake from failing to activate during the boost phase, cruise aircraft typically employ a fairing or intake cover on the nose. After the upper-stage aircraft accelerates and enters the flight window, the upper stage separates from the interstage section and boosters. Subsequently, the fairing or intake cover opens, and the intake activates, activating the ramjet engine. This approach adds unnecessary weight to the nose fairing or intake cover and requires a complex ejection separation system, increasing the overall complexity of the aircraft system and introducing additional separation technology risks. Summary of the Invention

[0004] (a) Purpose of the invention The purpose of this invention is to provide an interstage section of an air-breathing aircraft with a venting function, which aims to solve the problems of large airflow resistance and complex structure in the boost phase of traditional aircraft, which are not conducive to separation.

[0005] (II) Technical Solution To address the aforementioned problems, the present invention provides an interstage section of an air-breathing aircraft with a venting function, used to connect the upper stage and the booster of the air-breathing aircraft. The interstage section includes a front section, a rear section, multiple connecting arms, and a separation assembly. The front section is connected to the rear section via the multiple connecting arms, and a venting channel is formed between the multiple connecting arms. The front section of the interstage section is connected to the tail end of the upper stage, and the front section of the interstage section forms the inlet of the bleed channel. The inlet of the bleed channel corresponds to the position of the tail nozzle of the upper stage. The rear section of the interstage section is connected to the booster. The front section of the interstage is connected to the tail end of the upper stage via the separation component, which is used to quickly separate the upper stage from the interstage during the separation phase.

[0006] Preferably, the interstage section further includes an oblique flow guide section, which is connected to the rear section of the interstage section. The oblique flow guide section can convert the forward airflow into an oblique airflow along its surface and guide the oblique airflow to the outlet of the discharge channel.

[0007] Preferably, the inclined guide section is a central cone, the bottom surface of which is connected to the rear section of the interstage section, and the cone surface of which faces the inlet of the discharge channel.

[0008] Preferably, the connecting arm includes a first connecting portion and a second connecting portion, the first connecting portion and the second connecting portion being symmetrically arranged on both sides of the oblique guide portion.

[0009] Preferably, the connecting arm further includes a third connecting portion, which connects the top of the front section of the inter-stage segment and the top of the rear section of the inter-stage segment; The first connecting part connects the left side of the front segment of the inter-level segment and the left side of the rear segment of the inter-level segment, and the second connecting part connects the right side of the front segment of the inter-level segment and the right side of the rear segment of the inter-level segment, or the first connecting part connects the right side of the front segment of the inter-level segment and the right side of the rear segment of the inter-level segment, and the second connecting part connects the left side of the front segment of the inter-level segment and the left side of the rear segment of the inter-level segment.

[0010] Preferably, the separation assembly includes a plurality of explosive bolts and a plurality of thrust components. The plurality of explosive bolts are respectively connected to the first connecting part, the second connecting part and the third connecting part, and the plurality of thrust components are respectively connected to the first connecting part and the second connecting part. The explosive bolts are used for connection and unlocking between the upper stage and the inter-stage section, and the thrust components are used to provide thrust force during the separation process.

[0011] Preferably, the first connecting portion and the second connecting portion form a first cavity on the side near the upper stage. One end of the explosive bolt and the pusher component are disposed in the first cavity. During the separation process, the explosive bolt is electrically ignited and detonated, disconnecting the mechanical connection between the connecting arm and the upper stage. The elastic potential energy stored inside the pusher component is released to push the connecting arm to move, thereby completing the separation action.

[0012] Preferably, the separation assembly further includes a plurality of shear pins, which are respectively connected to the first connecting portion, the second connecting portion and the third connecting portion, and the shear pins are used to bear the shear stress between the upper stage and the inter-stage segment.

[0013] Preferably, the first connecting portion, the second connecting portion, and the third connecting portion are each provided with a plurality of shear pins, and the plurality of shear pins are evenly arranged along the periphery of the explosive bolt.

[0014] Preferably, a second cavity is formed on the second connecting part, a third cavity is formed between the inclined guide part and the rear section of the interstage section, a cable socket is provided at one end of the second connecting part near the front section of the interstage section, and a cable outlet is provided at the top of the third connecting part near the rear section of the interstage section. The cable socket is connected to the cable outlet in sequence through the second cavity and the third cavity.

[0015] (III) Beneficial Effects The above-described technical solution of the present invention has the following beneficial technical effects: 1. By creating a venting channel in the interstage section that directly connects to the upper stage's exhaust nozzle, with the venting channel directly corresponding to the nozzle location, a low-resistance exhaust path is provided for the engine's internal combustion gases, preventing airflow stagnation and pressure disturbance within the interstage section. This ensures that airflow consistently passes through the ramjet engine's internal channels during the boost phase, simulating its operating state and maintaining the stability of the inlet shock system. This guarantees seamless engine takeover after separation, significantly improving the aircraft's reliability and safety.

[0016] 2. Multiple connecting arms replace the integral interstage shell section, significantly reducing material usage while ensuring structural strength. The distributed layout of the connecting arms allows for optimized cross-sectional design based on stress requirements. For example, a hollow truss structure can be used to reduce structural weight under the same load-bearing capacity, thereby improving the overall thrust-to-weight ratio of the aircraft.

[0017] 3. The separation component independently handles connection and unlocking functions, avoiding the risks associated with traditional inter-stage segments relying on a single connection structure. Through a pre-defined separation interface and a fast unlocking mechanism, separation can be completed within milliseconds, reducing attitude interference during the separation process, making it particularly suitable for high-dynamic flight scenarios. Attached Figure Description

[0018] Figure 1 This is a structural schematic diagram of the location of the interstage section of an air-breathing aircraft with a venting function in the entire aircraft, according to the present invention. Figure 2 This is a schematic diagram of the structure of an interstage section of an air-breathing aircraft with a venting function according to the present invention; Figure 3 This is an exploded structural diagram of an interstage section of an air-breathing aircraft with a venting function, provided by the present invention. Figure 4 This is a front view of an interstage section of an air-breathing aircraft with a venting function, provided according to the present invention. Figure 5 This is a side view of an interstage section of an air-breathing aircraft with a venting function, provided by the present invention. Figure 6 This is a top view of an interstage section of an air-breathing aircraft with a venting function, provided by the present invention. Figure 7 This is a stress simulation diagram of the interstage section containing a central cone structure; Figure 8 This is a stress simulation diagram of the interstage section without a central cone structure.

[0019] Figure label: 100, Interstage section; 200, Upper stage; 300, Booster; 400, Cable housing; 1. The first segment of the inter-level segment; 2. The latter part of the inter-level segment; 3. Connecting arm; 3a. Drainage channel; 31. First connecting part; 32. Second connecting part; 321. Cable socket; 33. Third connecting part; 33a. Cable outlet; 34. Fourth connecting part; 35. Mounting cover; 4. Separation assembly; 41. Explosion bolt; 42. Push-bump assembly; 43. Shear pin; 5. Angled flow guide section. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0021] The accompanying drawings illustrate a layer structure according to an embodiment of the present invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0022] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] Combination Figures 1 to 6 This invention provides an interstage section 100 of an air-breathing aircraft with a venting function, used to connect the upper stage 200 and the booster 300 of the air-breathing aircraft. The interstage section 100 includes a front section 1, a rear section 2, multiple connecting arms 3, and a separation assembly 4. The front section 1 is connected to the rear section 2 via multiple connecting arms 3, and a venting channel 3a is formed between the multiple connecting arms 3. The front section 1 is connected to the tail end of the upper stage 200, and the front section 1 has an inlet for the venting channel 3a, the inlet of which corresponds to the position of the tail nozzle of the upper stage 200. The rear section 2 is connected to the booster 300. The front section 1 is connected to the tail end of the upper stage 200 via the separation assembly 4, which is used to quickly separate the upper stage 200 from the interstage section 100 during the separation phase.

[0025] Specifically, the first stage section 1 of the interstage section is located on the side of the interstage section 100 closest to the upper stage 200. Its front end is connected to the tail end of the upper stage 200 via a separation assembly 4, and its rear end is connected to the last stage section 2 of the interstage section via a connecting arm 3. The front end forms the inlet of the effluent channel 3a, and the inlet position corresponds to the position of the tail nozzle of the upper stage 200, which is used to receive the airflow discharged from the tail nozzle. The last stage section 2 of the interstage section is located on the side of the interstage section 100 closest to the booster 300. Its front end is connected to the first stage section 1 of the interstage section via a connecting arm 3, and its rear end is directly fixedly connected to the booster 300, serving as the connection carrier between the interstage section 100 and the booster 300. Multiple connecting arms 3 are distributed circumferentially along the interstage section 100, with their ends fixedly connected to the front section 1 and the rear section 2 of the interstage section, respectively. The connecting arms 3 are elongated, and their shape is determined according to the specific structure and size of the front section 1 and the rear section 2 of the interstage section, achieving a smooth connection between the front section 1 and the rear section 2. The gaps between the connecting arms 3 form the main body of the effluent channel 3a, which not only bears the mechanical transmission between the front and rear sections, such as axial thrust and radial load, but also provides a flow path for the airflow. The separation component 4 is installed at the connection interface between the front section 1 of the interstage section and the tail end of the upper stage 200, such as embedded in the front end face of the front section 1 of the interstage section or the tail end face of the upper stage 200. The rigid connection between the two is achieved by a mechanical locking structure, such as bolts or pins, and the locking can be quickly released after receiving a separation command.

[0026] During flight, the connecting arms 3 are spaced apart to form a venting channel 3a, with the channel inlet directly facing the upper stage 200's exhaust nozzle. The high-speed airflow exiting the exhaust nozzle can directly enter the venting channel 3a and be diagonally discharged from the rear section 2 of the interstage section, preventing airflow accumulation in the interstage region and the formation of turbulence or pressure fluctuations. During separation, the separation assembly 4 receives a command and quickly unlocks, releasing the mechanical connection between the front section 1 of the interstage section and the upper stage 200, thus separating the upper stage 200 from the booster 300 along with the interstage section 100.

[0027] This configuration, with a venting channel 3a directly connected to the exhaust nozzle of the upper stage 200 in the interstage section 100, directly corresponding to the exhaust nozzle location, provides a low-resistance exhaust path for the internal combustion gases of the engine, preventing airflow stagnation and pressure disturbance within the interstage section 100. This ensures that during the boost phase, airflow always passes through the internal flow channels of the ramjet engine, simulating its operating state and maintaining the stability of the intake shock system. This ensures seamless engine takeover after separation, greatly improving the reliability and safety of the aircraft. Multiple connecting arms 3 replace the integral interstage shell section, significantly reducing material usage while maintaining structural strength. The distributed layout of the connecting arms 3 allows for optimized cross-sectional design based on stress requirements, such as using a hollow truss structure to reduce structural weight under the same load-bearing capacity and improve the overall thrust-to-weight ratio of the aircraft. The separation component 4 independently undertakes the connection and unlocking functions, avoiding the risk of the traditional interstage section 100 relying on a single connecting structure. With a preset separation interface and a fast unlocking mechanism, the separation action can be completed in milliseconds, reducing attitude interference during the separation process, which is especially suitable for high-dynamic flight scenarios.

[0028] In a preferred embodiment, the interstage section 100 further includes an oblique flow guide 5, which is connected to the rear section 2 of the interstage section. The oblique flow guide 5 can convert the forward airflow into an oblique airflow along its surface and guide the oblique airflow to the outlet of the venting channel 3a.

[0029] Specifically, the oblique guide section 5 is fixedly connected to the front end face of the rear section 2 of the interstage section, near the side of the connecting arm 3, and its position is inside the venting channel 3a, preferably at the center of the channel. The curved surface faces the inlet of the venting channel 3a, and the surface forms a preset angle with the axial direction, that is, there is an angle between the flow direction of the venting channel 3a and the flight direction of the aircraft. In optional cases, the angle range is 15°-45°, which is used to contact and guide the airflow entering the channel. When the positive airflow discharged from the exhaust nozzle of the upper stage 200 flows axially into the venting channel 3a, it first contacts the inclined surface of the oblique guide section 5. Since there is an angle between the surface of the guide section and the airflow direction, the airflow will be deflected along the curved surface, changing from axial flow to oblique flow along the curved surface. Under the guidance of the oblique guide section 5, the oblique airflow flows to the outlet of the venting channel 3a, that is, the gap formed between the connecting arm 3 and the rear section, avoiding the airflow directly impacting the end face of the rear section 2 of the interstage section to generate reflected shock waves, and at the same time reducing the energy loss of the airflow in the channel, such as the pressure loss caused by eddies.

[0030] This design allows the oblique guide to suppress airflow separation. Direct airflow impacts the airflow, easily creating vortices at corners. The oblique guide 5, with its smooth curved surface, guides the airflow, resulting in a more uniform velocity distribution and reduced turbulence intensity, especially reducing shock wave drag during supersonic flight. Optimized airflow direction ensures the exhaust gas from the tailpipe passes more efficiently through the discharge channel 3a. In traditional non-guided structures, some airflow impacts the inner wall of the interstage section 100, resulting in heat loss. The oblique guide retains most of this kinetic energy and directs it along the discharge channel 3a, improving propulsion efficiency. Furthermore, the inner side of the connecting arm 3 connects to the outer side of the oblique guide 5. The oblique guide 5 transforms concentrated impact loads into distributed loads along the surface, reducing alternating stress on the connecting arm 3, lowering the risk of fatigue cracks, and extending component lifespan.

[0031] The specific shape of the oblique flow guide 5 is not limited here, as long as it can achieve the above-mentioned oblique flow guidance. For example, a conical or pyramidal structure can be used. In a preferred embodiment, the oblique flow guide 5 is a central cone, the bottom surface of which is connected to the rear section 2 of the interstage section, and the conical surface of the central cone faces the inlet of the discharge channel 3a.

[0032] Specifically, the central cone has a conical structure with a large-diameter bottom surface, which is coaxially and fixedly connected to the front end of the rear section 2 of the interstage section, such as by bolts or integral molding. The apex of the cone faces the inlet of the discharge channel 3a, i.e., directly opposite the tail nozzle of the upper stage 200; the cone surface is a smooth curved surface. The central cone is fixed to the rear section 2 of the interstage section through coaxial arrangement. Its conical structure allows the axial airflow entering the discharge channel 3a to diffuse evenly along the cone surface. After the airflow contacts the cone surface, it deflects outward along the surface, forming an outward oblique airflow, and finally exits from the channel outlet between the connecting arms 3. Due to the circumferential symmetry of the conical structure, it can ensure that the airflow is evenly distributed circumferentially in the channel, avoiding local erosion of the channel wall caused by unilateral airflow deflection; at the same time, the gradual expansion characteristic of the cone surface allows the airflow to gradually decelerate and the pressure to change smoothly, reducing the generation of shock waves.

[0033] This symmetrical design of the central cone ensures uniform circumferential airflow distribution, preventing localized high-speed airflow from eroding the channel walls, making it particularly suitable for the exhaust flow requirements of high-flow-rate engines. The central cone dynamically adapts to changes in flight altitude based on airflow expansion. At low altitudes and high pressure, the airflow adheres closely to the cone surface; at high altitudes and low pressure, the airflow naturally expands along the cone surface, maintaining optimal expansion and achieving wide-range pressure adaptation without additional adjustment mechanisms. The conical structure possesses inherent mechanical advantages: the large-diameter connection at the base disperses loads, while the small cross-section at the tip reduces aerodynamic drag. It is less prone to deformation under severe aerodynamic loads and separation impacts, improving overall structural stability and flight smoothness.

[0034] It should be noted that the specific distribution of the connecting arm 3 is not limited here, as long as it can form a discharge channel 3a after the interstage section 1 and the interstage section 2 are connected to achieve discharge. In a preferred embodiment, the connecting arm 3 includes a first connecting part 31 and a second connecting part 32, which are symmetrically arranged on both sides of the oblique guide section 5.

[0035] Specifically, the first connecting part 31 is a long strip-shaped structure, with one end fixedly connected to the first side of the front section 1 of the interstage section, for example, the left side of the front section 1 of the interstage section, and the other end fixedly connected to the left side of the rear section 2 of the interstage section; one end of the second connecting part 32 is connected to the second side of the front section 1 of the interstage section, i.e., the right side of the front section 1 of the interstage section, and the other end is connected to the right side of the rear section 2 of the interstage section. The first connecting part 31 and the second connecting part 32 are symmetrically arranged on both sides of the oblique guide section 5 to achieve balanced force and avoid bending or torsional deformation of the interstage section 100 due to unilateral force. At the same time, the symmetrically distributed connecting parts form symmetrical venting channels 3a on both sides of the oblique guide section 5, so that the oblique airflow guided by the oblique guide section 5 can pass symmetrically through the channels on both sides, further ensuring the circumferential uniformity of the airflow. Here, left and right refer to the flight direction of the aircraft, relative to the left and right sides of the aircraft.

[0036] like Figure 4 As shown, Figure 4 This is a front view of the interstage section 100. The symmetrical arrangement of the first connecting portion 31 and the second connecting portion 32 can be achieved by symmetrically arranging them circumferentially along the outer side of the oblique guide portion 5. That is, the first connecting portion 31 and the second connecting portion 32 are located at either end of any diameter in the circle shown in the figure. When multiple first connecting portions 31 and multiple second connecting portions 32 are provided, the multiple first connecting portions 31 and multiple second connecting portions 32 are also correspondingly arranged at both ends of different diameters. Alternatively, to ensure stable flight of the aircraft, the first connecting portions 31 and the second connecting portions 32 can be symmetrically arranged along a vertical axis. Figure 4 As shown, the first connecting part 31 and the second connecting part 32 are located at the same height and are symmetrically distributed from left to right. When multiple first connecting parts 31 and multiple second connecting parts 32 are provided, the first connecting parts 31 and the second connecting parts 32 are symmetrically distributed from left to right in a one-to-one correspondence.

[0037] This symmetrical layout ensures a uniform distribution of shear force and bending moment, effectively suppressing bending deformation of the interstage section 100, especially when the booster 300 thrust is eccentric. The symmetrical cross-section of the venting channel 3a formed by the two connecting parts prevents airflow deviation within the channel, reducing aircraft attitude disturbances caused by flow asymmetry and improving flight stability. The symmetrical structure reduces manufacturing and assembly precision requirements; the left and right connecting parts can be machined using the same molds, and rapid calibration during assembly using symmetrical positioning benchmarks improves assembly efficiency while reducing cumulative errors caused by part differences.

[0038] In a preferred embodiment, the first connecting portion 31 and the second connecting portion 32 are symmetrically arranged on the left and right sides of the oblique guide portion 5. The connecting arm also includes a third connecting portion 33, which connects the top of the front section 1 and the top of the rear section 2 of the interstage section. The first connecting portion 31 connects the left side of the front section 1 and the left side of the rear section 2, and the second connecting portion 32 connects the right side of the front section 1 and the right side of the rear section 2. Alternatively, the first connecting portion 31 connects the right side of the front section 1 and the right side of the rear section 2, and the second connecting portion 32 connects the left side of the front section 1 and the left side of the rear section 2. Here, left, right, and top specifically refer to the left and right sides and the top of the aircraft along the flight direction in a horizontal flight state.

[0039] Specifically, the third connecting part 33, similar to the first connecting part 31 and the second connecting part 32, is arranged along the top of the interstage section 100, with one end fixedly connected to the top of the front section 1 of the interstage section and the other end fixedly connected to the top of the rear section 2 of the interstage section; together with the first connecting part 31 and the second connecting part 32 arranged on the left and right, it forms a three-point connection structure at the top, left side and right side. At this time, under the condition of meeting the connection strength and leakage requirements, the first connecting part 31 and the second connecting part 32 can also be multiple of the same number, arranged symmetrically on the left and right sides of the oblique guide section 5.

[0040] This three-point layout enhances the overall rigidity of the interstage section 100. Under the complex loads generated by aircraft maneuvering, the triangular structure effectively resists structural deformation, ensuring the dimensional stability of the exhaust channel 3a. Each connecting part bears loads in different directions. The third connecting part 33 mainly bears axial tensile force, while the left and right connecting parts bear shear force and lateral force, maximizing the utilization of material properties. The open layout of the three-point connection provides a larger cross-sectional area for the exhaust channel 3a, which is particularly suitable for the exhaust requirements of high-thrust engines, avoiding pressure loss due to narrow channels. Furthermore, when there are multiple first connecting parts 31 and second connecting parts 32, the symmetrical arrangement on the left and right sides combined with the top third connecting part 33 has a similar effect to the three-point layout, which will not be elaborated further here.

[0041] In an optional configuration, the connecting arm 3 may also include a fourth connecting portion 34, which connects the bottom of the front section 1 of the interstage segment and the bottom of the rear section 2 of the interstage segment, thereby enhancing the integrity and structural strength of the interstage segment 100.

[0042] In a preferred embodiment, the separation assembly 4 includes a plurality of explosive bolts 41 and a plurality of thrusting components 42. The plurality of explosive bolts 41 are respectively connected to the first connecting part 31, the second connecting part 32 and the third connecting part 33, and the plurality of thrusting components 42 are respectively connected to the first connecting part 31 and the second connecting part 32. The explosive bolts 41 are used for connection and unlocking between the upper stage 200 and the interstage section 100, and the thrusting components 42 are used to provide thrusting force during the separation process.

[0043] Specifically, multiple explosive bolts 41 are respectively embedded in the front ends of the first connecting part 31, the second connecting part 32, and the third connecting part 33. One end of the explosive bolt 41 is fixed to the front section 1 of the interstage section, and the other end is locked to the corresponding interface at the tail end of the upper stage 200 to achieve a rigid connection between the two. It contains explosives and can instantly detonate and break to release the lock upon receiving a command. Multiple thrusting components 42 are installed at the front ends of the first connecting part 31 and the second connecting part 32. One end of the thrusting component 42 is fixed to the front section 1 of the interstage section, and the other end faces the tail end of the upper stage 200. It can be a spring, a gas actuator, etc., and can generate thrust in the separation direction after unlocking. During normal flight, the explosive bolts 41 are in a locked state, rigidly connecting the front section 1 of the interstage section to the tail end of the upper stage 200, and the thrusting components 42 are in a compressed energy storage state, like a compressed spring. During the separation phase, the control system sends a separation command, detonating the explosive inside the explosive bolt 41, causing the bolt to break and release the mechanical connection. Simultaneously, the thrust component 42 releases energy, such as spring extension and gas expansion, applying axial thrust to the upper stage 200, causing the upper stage 200 and the interstage section 100 to rapidly generate relative motion, forming a safe separation distance in a short time. Specifically, the explosive bolt 41 is a bolt component that carries a small amount of explosive and can achieve precise detonation, instantly releasing the connection and achieving separation. It is used for connecting and unlocking the upper stage 200 and the interstage section 100. The thrust component 42 is a device that stores elastic potential energy, similar to a spring. When the two connecting parts are mechanically unlocked, the elastic potential energy stored in the component is rapidly released, converting back into the kinetic energy of the two connecting parts. Therefore, the thrust component 42 can accelerate separation.

[0044] This configuration ensures the deterministic nature of the separation action through the instantaneous unlocking characteristic of the explosive bolts 41. Combined with the active thrust of the pusher component 42, it avoids the jamming problems that may occur with traditional mechanical unlocking, and can operate reliably even in high-vibration environments. The buffer thrust of the pusher component 42 reduces the impact load during the separation process. Compared to separation methods that rely solely on explosive force, the pusher force can be adjusted through structural design, reducing impact damage to the precision equipment of the upper stage 200 and protecting the payload. The multi-point arrangement of the explosive bolts 41 and the pusher component 42 allows for coordinated action. Unified timing control prevents attitude deviations of the upper stage 200 caused by asynchronous separation, ensuring the accuracy of the flight trajectory after separation.

[0045] In a preferred embodiment, a first cavity is formed on the side of the first connecting part 31 and the second connecting part 32 near the upper stage 200. One end of the explosive bolt 41 and the pusher component 42 is disposed in the first cavity. During the separation process, the explosive bolt 41 is electrically ignited and detonated, breaking the mechanical connection between the connecting arm 3 and the upper stage 200. The elastic potential energy stored inside the pusher component 42 is released to push the connecting arm 3 to move, thereby completing the separation action.

[0046] Specifically, the first cavity is a closed cavity inside the front end of the first connecting part 31 and the second connecting part 32. The cavity size matches the explosive bolt 41 and the thrust component 42. The main body of the explosive bolt 41 and one end of the thrust component 42 are installed in the first cavity, and the cavity is isolated from the outside by a sealing structure. During separation, the explosive bolt 41 explodes in the first cavity, and the high-temperature and high-pressure gas generated is sealed by the cavity, causing the pressure inside the cavity to rise instantaneously. The high-pressure gas pushes the movable end of the thrust component 42 outward, providing additional thrust for separation. On the other hand, the closed structure of the cavity can restrain the fragments generated by the explosion, such as bolt debris, and prevent the fragments from splashing and damaging the upper stage 200 tail nozzle, connecting arm 3 and other surrounding components. At the same time, the pressure in the first cavity acts evenly on the thrust component 42, making the thrust output more stable and avoiding the tilting of the thrust component 42 caused by single-point force, ensuring the stability of the upper stage 200's attitude during separation.

[0047] This design concentrates the explosion energy into thrust, improving energy efficiency and reducing the amount of pyrotechnics used. The sealed cavity design isolates explosion fragments and high-temperature gases, completely confining the fragments inside and preventing damage to critical components such as the tailpipe and cables, making it particularly suitable for high-density integrated interstage areas. The uniform pressure distribution within the cavity ensures stable force distribution on the thrust component 42, preventing excessively large instantaneous impact peaks during separation and protecting the connection structure from damage.

[0048] In a preferred embodiment, the separation assembly 4 further includes a plurality of shear pins 43, which are respectively connected to the first connecting portion 31, the second connecting portion 32 and the third connecting portion 33. The shear pins 43 are used to bear the shear stress between the upper stage 200 and the interstage segment 100.

[0049] Specifically, multiple shear pins 43 are cylindrical metal pins, respectively embedded in the first connecting part 31, the second connecting part 32, the third connecting part 33, and the connection interface of the upper stage 200. One end of the shear pin 43 is connected to the front section 1 of the interstage section, and the other end is inserted into the pin hole at the tail end of the upper stage 200, arranged parallel to the explosive bolt 41, to bear the shear stress of the connection interface, such as the shear force generated by lateral force and vibration load during flight. During normal flight, the shear pin 43 and the explosive bolt 41 work together to bear the force, mainly relying on the shear pin 43 to bear the lateral shear force, avoiding fatigue damage to the explosive bolt 41 due to long-term shear load. During the separation stage, after the explosive bolt 41 explodes and breaks, the shear pin 43 is sheared or falls off during the relative movement between the upper stage 200 and the interstage section 100, without hindering the separation action.

[0050] Through this configuration, the shear pin 43 shares the shear load of the explosive bolt 41, reducing the shear stress of the explosive bolt 41 and preventing premature failure of the bolt due to long-term shear fatigue, thus ensuring structural stability during booster flight. The shear pin 43 has a preset fracture strength lower than the main structure. When encountering unexpected overload, the shear pin 43 fractures first to absorb energy, preventing plastic deformation of the main structure of the interstage section 100, providing passive safety protection for the aircraft and reducing the risk of structural failure. The shear pin 43 maintains connection stability before separation. In the milliseconds before the explosive bolt 41 detonates, the shear pin 43 can temporarily withstand the separation impact load, preventing premature relative displacement and ensuring that the separation action is precisely executed at the preset position.

[0051] In a preferred embodiment, the first connecting portion 31, the second connecting portion 32, and the third connecting portion 33 are each provided with a plurality of anti-shear pins 43, which are evenly arranged along the periphery of the explosion bolt 41.

[0052] Specifically, shear pins 43 are circumferentially and evenly distributed at each connection interface of the first connection 31, the second connection 32, and the third connection 33. Multiple shear pins 43 are evenly distributed along the circumference of the explosive bolt 41, such as 3-4 shear pins 43 forming a ring support around the explosive bolt 41. The even distribution of shear pins 43 along the circumference of the explosive bolt 41 can evenly distribute the shear load of the connection interface to each shear pin 43, preventing premature breakage of a single shear pin due to overload. This arrangement enhances the circumferential stiffness of the connection interface, reduces the relative torsion between the upper stage 200 and the interstage section 100, and ensures the stability of the relative position between the inlet of the effluent channel 3a and the tailpipe.

[0053] This arrangement, with uniformly distributed shear pins 43, reduces the load variation borne by each shear pin 43, preventing overload fracture of a single shear pin 43 and ensuring the overall reliability of the connection system. The multi-point distribution reduces the machining accuracy requirements of individual parts; even if a shear pin 43 has a slight dimensional deviation, other shear pins 43 can compensate for the error through load redistribution, reducing manufacturing costs. Under aircraft vibration and impact loads, the uniformly distributed shear pins 43 can suppress resonance in the connection, avoid the engine's operating vibration frequency range, and reduce fatigue damage accumulation.

[0054] In a preferred embodiment, a second cavity is formed on the second connecting part 32, a third cavity is formed between the oblique flow guide part 5 and the rear section 2 of the interstage section, a cable socket 321 is provided at one end of the second connecting part 32 near the front section 1 of the interstage section, and a cable outlet 33a is provided at the top of the third connecting part 33 near the rear section 2 of the interstage section. The cable socket 321 is connected to the cable outlet 33a through the second cavity and the third cavity in sequence.

[0055] Specifically, the second cavity is an elongated cavity inside the second connecting part 32, extending along the length of the connecting part. One end communicates with the interior of the front section 1 of the interstage section, and the other end communicates with the third cavity. The third cavity is an annular or elongated cavity between the oblique flow guide 5 and the rear section 2 of the interstage section. One end communicates with the second cavity, and the other end extends to the top of the rear section 2 of the interstage section. The cable socket 321 is fixed to the inner side of the second connecting part 32 near the front section 1 of the interstage section, and is used to connect the cable plug of the upper stage 200. The interface is matched with the signal or power line of the upper stage 200. The cable outlet 33a is opened in the third connecting part 33 near the top of the rear section 2 of the interstage section. It is the outlet for the cable leading from the interstage section 100 to the booster 300 and is equipped with a sealing structure. After the cable passes through the cable outlet 33a, it is inserted into the cable cover 400 of the aircraft. The subsequent installation and layout methods are not limited here.

[0056] The signal or power cable between the upper stage 200 and the booster 300 is connected via a built-in path: one end of the cable is inserted into the cable socket 321 and connected to the upper stage 200, and the other end passes through the second cavity and the third cavity in sequence, and finally leads out from the cable outlet 33a and connects to the booster 300.

[0057] This design provides mechanical and environmental protection for the cable through the second and third cavities. The temperature inside the cavities is significantly lower than that at the outlet channel 3a, preventing cable wear caused by vibration and improving signal transmission reliability. The wiring function is achieved using the structural space of the connection section, eliminating the need for additional cable supports. Reducing the overall size and dimensions of the interstage section 100 lowers aerodynamic drag and structural weight, meeting the lightweight design requirements of the aircraft. Modular cavity wiring facilitates troubleshooting and replacement. The standardized interface design of the cable socket 321 and the outlet shortens the time required for cable insertion and removal. Furthermore, a test channel can be reserved inside the cavity, allowing for cable continuity testing without disassembling the interstage section 100, reducing maintenance costs. Additionally, the connection section is equipped with a mounting cover 35, which is detachably connected to the connection section, further improving installation and maintenance efficiency.

[0058] Combination Figure 7 and Figure 8 , Figure 7 and Figure 8The figures show the stress simulation diagrams of interstage section 100 with and without the central cone structure, respectively. Numerical simulations show that the central cone design reduces the drag of interstage section 100 by 22.4%, demonstrating its effective ability to reduce drag during the booster phase. The central cone structure in interstage section 100 transforms the normal shock wave into a conical oblique shock wave, reducing drag and thermal load. Furthermore, the space between the central cone of interstage section 100 and the booster 300 can serve as installation space for equipment such as the explosive bolt 41 detonator, achieving structural functional reuse.

[0059] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. An interstage section of an air-breathing aircraft with a bleed-out function, used to connect the upper stage and the booster of the air-breathing aircraft, characterized in that, The interstage section includes a front section, a rear section, multiple connecting arms, and a separation assembly. The front section is connected to the rear section via the multiple connecting arms, and a discharge channel is formed between the multiple connecting arms. The front section of the interstage section is connected to the tail end of the upper stage, and the front section of the interstage section forms the inlet of the bleed channel. The inlet of the bleed channel corresponds to the position of the tail nozzle of the upper stage. The rear section of the interstage section is connected to the booster. The front section of the interstage is connected to the tail end of the upper stage via the separation component, which is used to quickly separate the upper stage from the interstage during the separation phase.

2. The interstage section of the air-breathing aircraft according to claim 1, characterized in that, The interstage section also includes an oblique flow guide section, which is connected to the rear section of the interstage section. The oblique flow guide section can convert the forward airflow into an oblique airflow along its surface and guide the oblique airflow to the outlet of the discharge channel.

3. The interstage section of the air-breathing aircraft according to claim 2, characterized in that, The inclined guide section is a central cone, the bottom surface of which is connected to the rear section of the interstage section, and the cone surface of which faces the inlet of the discharge channel.

4. The interstage section of the air-breathing aircraft according to claim 2, characterized in that, The connecting arm includes a first connecting part and a second connecting part, which are symmetrically arranged on both sides of the oblique guide section.

5. The interstage section of the air-breathing aircraft according to claim 4, characterized in that, The connecting arm further includes a third connecting part, which connects the top of the front section of the interstage segment and the top of the rear section of the interstage segment; The first connecting part connects the left side of the front segment of the inter-level segment and the left side of the rear segment of the inter-level segment, and the second connecting part connects the right side of the front segment of the inter-level segment and the right side of the rear segment of the inter-level segment, or the first connecting part connects the right side of the front segment of the inter-level segment and the right side of the rear segment of the inter-level segment, and the second connecting part connects the left side of the front segment of the inter-level segment and the left side of the rear segment of the inter-level segment.

6. The interstage section of the air-breathing aircraft according to claim 5, characterized in that, The separation assembly includes multiple explosive bolts and multiple thrust components. The multiple explosive bolts are respectively connected to the first connecting part, the second connecting part, and the third connecting part. The multiple thrust components are respectively connected to the first connecting part and the second connecting part. The explosive bolts are used for connection and unlocking between the upper stage and the inter-stage section. The thrust components are used to provide thrust force during the separation process.

7. The interstage section of the air-breathing aircraft according to claim 6, characterized in that, The first connecting part and the second connecting part have a first cavity formed on the side near the upper stage. One end of the explosive bolt and the pusher component are disposed in the first cavity. During the separation process, the explosive bolt is electrically ignited and detonated, breaking the mechanical connection between the connecting arm and the upper stage. The elastic potential energy stored inside the pusher component is released to push the connecting arm to move, thereby completing the separation action.

8. The interstage section of an air-breathing aircraft according to claim 6, characterized in that, The separation assembly also includes a plurality of shear pins, which are respectively connected to the first connecting portion, the second connecting portion and the third connecting portion. The shear pins are used to bear the shear stress between the upper stage and the interstage section.

9. The interstage section of an air-breathing aircraft according to claim 8, characterized in that, The first connecting part, the second connecting part and the third connecting part are each provided with a plurality of shear pins, and the plurality of shear pins are evenly arranged along the periphery of the explosive bolt.

10. The interstage section of the air-breathing aircraft according to claim 7, characterized in that, A second cavity is formed on the second connecting part, and a third cavity is formed between the inclined flow guide part and the rear section of the interstage section. A cable socket is provided at one end of the second connecting part near the front section of the interstage section, and a cable outlet is provided at the top of the third connecting part near the rear section of the interstage section. The cable socket is connected to the cable outlet through the second cavity and the third cavity in sequence.

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