A thermal matching compensator for a high speed aircraft

Abstract

This invention provides a thermal matching compensator for high-speed aircraft, relating to the field of high-speed aircraft. It includes a compensating outer cylinder, which is hollow inside, with one end connected to the combustion chamber of a ramjet engine; a compensating inner cylinder, extending into the outer cylinder from the other end and slidingly engaged with it, with the end of the inner cylinder away from the outer cylinder connected to the corresponding air intake of the ramjet engine; a sliding gap between the outer wall of the inner cylinder and the inner wall of the outer cylinder; and a sealing assembly disposed between the outer and inner walls of the inner and outer cylinders, comprising a perfluoroether sealing ring and a quartz packing sealing ring spaced axially along the inner cylinder, the perfluoroether sealing ring and the quartz packing sealing ring cooperating to seal the sliding gap. The compensator provided by this invention, while compensating for thermal deformation of the air intake and combustion chamber, possesses better durability and sealing performance.

Description

Technical Field

[0001] This invention relates to the field of high-speed aircraft, and more particularly to a thermal matching compensator for high-speed aircraft. Background Technology

[0002] As a core power component of high-speed aircraft propulsion systems, ramjet engines experience dramatic temperature rises during high-speed flight, leading to significant thermal deformation at the connection between the intake and combustion chamber. This places extremely high demands on the thermal deformation compensation capability and long-term high-temperature sealing performance of the connection structure. Currently, ramjet engine intakes and combustion chambers primarily utilize either rigid bolted flange connections or metal bellows connections. Rigid bolted flange connections completely constrain the thermal displacement of the intake and combustion chamber, preventing effective release of thermal deformation generated during operation. This causes the flange and connecting bolts to continuously bear substantial alternating thermal stress. Under repeated hot and cold thermal cycles, this easily leads to bolt loosening, flange warping, end-face seal failure, and gas leakage. While metal bellows can absorb some thermal displacement, the bellows wall is directly exposed to the high-temperature combustion gas environment. Under long-term high-temperature conditions, it is prone to material creep and mechanical strength degradation. After prolonged service, it often experiences wall wear and cracking, resulting in gas leakage.

[0003] In summary, there is an urgent need for a thermal matching compensator that can compensate for the thermal deformation of the intake manifold and combustion chamber, and has better sealing performance and durability. Summary of the Invention

[0004] The purpose of this invention is to provide a thermal matching compensator for high-speed aircraft, which can compensate for the thermal deformation of the air intake and combustion chamber while preventing gas leakage generated by combustion and ensuring the sealing performance of the ramjet engine.

[0005] This invention provides a thermal matching compensator for high-speed aircraft, comprising: The compensating outer cylinder is hollow inside, and one end of the compensating outer cylinder is connected to the combustion chamber of the ramjet engine; The compensating inner cylinder extends into the interior of the compensating outer cylinder from the other end and slides with the compensating outer cylinder. The end of the compensating inner cylinder away from the compensating outer cylinder is connected to the air intake corresponding to the ramjet engine. A sliding gap is provided between the outer wall surface of the compensating inner cylinder and the inner wall surface of the compensating outer cylinder. A sealing assembly is disposed between the outer wall surface of the inner compensating cylinder and the inner wall surface of the outer compensating cylinder, and includes a perfluoroether sealing ring and a quartz packing sealing ring spaced apart along the axial direction of the inner compensating cylinder. The perfluoroether sealing ring and the quartz packing sealing ring are used to cooperate with each other to seal the sliding gap.

[0006] According to the technical solutions provided in certain embodiments of the present invention, the quartz packing seal is disposed on the side of the perfluoroether seal near the combustion chamber of the ramjet engine.

[0007] According to certain embodiments of the present invention, the compensator further includes a sealing ring, which is disposed at the other end of the compensating outer cylinder and fixedly connected to the compensating outer cylinder. A first mounting cavity is formed between the sealing ring, the outer wall surface of the compensating inner cylinder, and the inner wall surface of the compensating outer cylinder. The perfluoroether sealing ring is disposed in the first mounting cavity, and the radial depth of the first mounting cavity is less than the diameter of the perfluoroether sealing ring in its free state.

[0008] According to certain embodiments of the present invention, an installation groove is provided on the outer wall surface of the compensation inner cylinder, and a second installation cavity is formed between the wall surface of the installation groove and the inner wall surface of the compensation outer cylinder. The quartz packing seal is disposed in the second installation cavity, and the radial depth of the second installation cavity is less than the diameter of the quartz packing seal in its free state.

[0009] According to the technical solutions provided in some embodiments of the present invention, the compensator further includes a limiting member, which extends axially along the inner cylinder of the compensator, and one end is fixedly connected to the sealing pressure ring, and the other end is slidably connected to the inner cylinder of the compensator, for limiting the axial relative sliding stroke between the inner cylinder of the compensator and the outer cylinder of the compensator.

[0010] According to the technical solutions provided in some embodiments of the present invention, the compensator further includes an indicator, which is disposed on the outer wall surface of the inner compensator and extends along the axial direction of the inner compensator. The indicator is provided with a distance scale for slidingly engaging with the limiting member to indicate the axial relative sliding amount between the inner compensator and the outer compensator.

[0011] According to some embodiments of the present invention, the compensator further includes a detection component, the detection component comprising: Two temperature sensors are respectively installed on the outer compensation cylinder and the inner compensation cylinder, and are used to detect the temperature inside the outer compensation cylinder and the inner compensation cylinder, respectively. Two pressure detection elements are respectively installed on the outer compensation cylinder and the inner compensation cylinder, and are used to detect the pressure inside the outer compensation cylinder and the inner compensation cylinder, respectively.

[0012] According to certain embodiments of the present invention, the inner wall of the compensating inner cylinder is coated with a heat-insulating coating.

[0013] According to certain embodiments of the present invention, at a reference temperature, the sliding clearance is greater than or equal to the limit clearance threshold; the limit clearance threshold is determined based on the expansion change of the compensator at the limit operating temperature calculated based on the reference temperature, the outer radius and linear expansion coefficient of the compensated inner cylinder at the reference temperature, the inner diameter and linear expansion coefficient of the compensated outer cylinder at the reference temperature, the limit operating temperature of the compensator, and the safe clearance threshold of the sliding clearance at the limit operating temperature. In summary, this invention provides a thermal matching compensator for a high-speed aircraft, comprising a compensating outer cylinder, the outer cylinder being hollow inside, and one end of the outer cylinder being connected to the combustion chamber of a ramjet engine; a compensating inner cylinder, the inner cylinder extending into the outer cylinder from the other end of the outer cylinder and slidingly engaging with the outer cylinder, the end of the inner cylinder away from the outer cylinder being connected to the air intake corresponding to the ramjet engine; a sliding gap being provided between the outer wall surface of the inner cylinder and the inner wall surface of the outer cylinder; and a sealing assembly, the sealing assembly being disposed between the outer wall surface of the inner cylinder and the inner wall surface of the outer cylinder, comprising a perfluoroether sealing ring and a quartz packing sealing ring spaced apart along the axial direction of the inner cylinder, the perfluoroether sealing ring and the quartz packing sealing ring being used to cooperate with each other to seal the sliding gap. This invention relies on the difference in thermal expansion deformation generated by the intake and combustion chamber of a ramjet engine as the driving force. When the ramjet engine heats up and operates, the combustion chamber side and the intake side undergo axial elongation deformation, pushing the inner and outer compensation cylinders to slide relative to each other axially. This absorbs the difference in axial thermal deformation between the intake and combustion chambers, releases internal thermal stress, and avoids problems such as flange warping and bolt breakage caused by rigid connections. A sliding gap is reserved between the outer wall of the inner compensation cylinder and the inner wall of the outer compensation cylinder to offset the difference in radial thermal expansion between the inner and outer compensation cylinders, preventing them from seizing up at high temperatures and causing the compensator to fail, thus allowing the compensator to be used for a long time. A double sealing structure of perfluoroether sealing ring and quartz packing sealing ring is used to seal the sliding gap, avoiding the shortcomings of a single sealing structure that is prone to aging failure and wear leakage at high temperatures. Through the synergistic cooperation of the above-mentioned axial sliding compensation structure, sliding gap design, and double sealing structure, the thermal compensator can compensate for the thermal deformation of the intake and combustion chamber while improving durability and sealing performance.

[0014] It should be understood that the descriptions of technical features, technical solutions, beneficial effects, or similar language in this invention do not imply that all features and advantages can be achieved in any single embodiment. Rather, it is understood that the description of a feature or beneficial effect means that a specific technical feature, technical solution, or beneficial effect is included in at least one embodiment. Therefore, the descriptions of technical features, technical solutions, or beneficial effects in this specification do not necessarily refer to the same embodiment. Furthermore, the technical features, technical solutions, and beneficial effects described in this embodiment can be combined in any suitable manner. Those skilled in the art will understand that embodiments can be implemented without one or more specific technical features, technical solutions, or beneficial effects of a particular embodiment. In other embodiments, additional technical features and beneficial effects may be identified in specific embodiments that do not embody all embodiments. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a thermal matching compensator for a high-speed aircraft, provided as an embodiment of the present invention. Figure 2 A cross-sectional schematic diagram of a thermal matching compensator for a high-speed aircraft provided in an embodiment of the present invention; Figure 3 This is a partially enlarged schematic diagram of a thermal matching compensator for a high-speed aircraft, provided as an embodiment of the present invention. Figure 4 This is a schematic diagram of the overflow path of high-temperature gas provided in an embodiment of the present invention.

[0017] The text labels in the image represent: 1. Compensating outer cylinder; 2. Compensating inner cylinder; 3. Sealing assembly; 31. Perfluoroether sealing ring; 32. Quartz packing sealing ring; 4. Sealing pressure ring; 7. Limiting element; 8. Indicating element; 91. Temperature detection element; 92. Pressure detection element; 10. Sliding clearance. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. This description is merely illustrative and explanatory, and should not be construed as limiting the scope of protection of the present invention in any way. Specifically, the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort should fall within the scope of protection of the present invention.

[0019] It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

[0020] As mentioned in the background section, in view of the problems in the prior art, this embodiment provides a thermal matching compensator for high-speed aircraft, comprising: The outer compensation cylinder 1 is hollow inside, and one end of the outer compensation cylinder 1 is connected to the combustion chamber of the ramjet engine. The inner compensating cylinder 2 extends into the outer compensating cylinder 1 from the other end of the outer compensating cylinder 1 and slides with it. The end of the inner compensating cylinder 2 away from the outer compensating cylinder 1 is connected to the air intake corresponding to the ramjet engine. A sliding gap 10 is provided between the outer wall surface of the inner compensating cylinder 2 and the inner wall surface of the outer compensating cylinder 1. The sealing assembly 3 is disposed between the outer wall surface of the inner compensating cylinder 2 and the inner wall surface of the outer compensating cylinder 1. It includes a perfluoroether sealing ring 31 and a quartz packing sealing ring 32 spaced apart along the axial direction of the inner compensating cylinder 2. The perfluoroether sealing ring 31 and the quartz packing sealing ring 32 are used to cooperate with each other to seal the sliding gap 10.

[0021] For details, please refer to Figure 1The thermal matching compensator for high-speed aircraft provided in this embodiment includes a compensating outer cylinder 1, a compensating inner cylinder 2, and a sealing assembly 3. Both the compensating outer cylinder 1 and the compensating inner cylinder 2 are hollow cylindrical bodies. One end of the compensating outer cylinder 1 is connected to the combustion chamber of the ramjet engine, and the compensating inner cylinder 2 extends into the outer cylinder 1 from the other end. The outer diameter of the compensating inner cylinder 2 is adapted to the inner diameter of the outer cylinder 1, forming a sliding fit structure. The end of the compensating inner cylinder 2 away from the outer cylinder 1 is connected to the air intake of the ramjet engine. Because the compensating outer cylinder 1 and the compensating inner cylinder 2 are in a sliding fit and are respectively connected to the air intake and the combustion chamber, when the air intake and the combustion chamber undergo axial deformation due to heat during operation, the compensating inner cylinder 2 can be pushed to slide relative to the compensating outer cylinder 1 to absorb the thermal deformation of the air intake and the combustion chamber. A sliding gap 10 is provided between the outer wall surface of the compensating inner cylinder 2 and the inner wall surface of the compensating outer cylinder 1 to prevent the compensating inner cylinder 2 and the compensating outer cylinder 1 from seizing due to thermal expansion at high temperatures, which would cause the compensator to fail and become unable to slide. The sealing assembly is located between the outer wall of the inner compensating cylinder 2 and the inner wall of the outer compensating cylinder 1. It includes two sealing structures: a quartz packing seal ring 31 and a perfluoroether seal ring 32. The two are spaced apart along the axial direction of the inner compensating cylinder 2. This allows high-temperature gas overflowing from the inner compensating cylinder 2 or the outer compensating cylinder 1 to flow into the sliding gap 10 and be blocked step by step by the two sealing structures, forming a double sealing barrier with graded isolation. When the first sealing structure leaks or fails due to aging, the second sealing structure can continue to trap the residual high-temperature medium, preventing a large amount of gas from leaking out, thereby improving the overall sealing reliability of the compensator and its service life under high-temperature conditions.

[0022] This invention utilizes the difference in thermal expansion deformation generated by the heating of the intake manifold and combustion chamber of a ramjet engine as the driving force. During ramjet engine heating and operation, axial elongation deformation occurs on both the combustion chamber side and the intake manifold side, driving the compensating inner cylinder 2 and the compensating outer cylinder 1 to slide relative to each other axially. This absorbs the difference in axial thermal deformation between the intake manifold and combustion chamber, releases the thermal stress accumulated inside the structure, and avoids the defects of flange warping and bolt breakage that easily occur when the intake manifold and combustion chamber are directly connected. A sliding gap 10 is reserved between the outer wall of the compensating inner cylinder 2 and the inner wall of the compensating outer cylinder 1. This sliding gap 10 can offset the difference in thermal expansion deformation between the compensating inner cylinder 2 and the compensating outer cylinder 1. The difference in radial thermal expansion between the outer cylinder and the inner cylinder 1 prevents the cylinders from seizing up under high-temperature conditions, reducing the risk of compensator failure and extending the service life of the compensator. The sealing assembly 3 uses a two-layer sealing structure of perfluoroether sealing ring 31 and quartz packing sealing ring 32 to seal the sliding gap 10, overcoming the defects of a single sealing element being prone to aging and wear and leakage after long-term high-temperature operation. Relying on the synergistic effect of the axial sliding compensation structure, the sliding gap 10 and the sealing assembly 3, the compensator can compensate for the thermal deformation of the intake and combustion chamber while also having better high-temperature durability and sealing performance.

[0023] In a preferred embodiment, the quartz packing seal 32 is disposed on the side of the perfluoroether seal 31 near the combustion chamber of the ramjet engine.

[0024] Specifically, such as Figure 2 As shown, in this embodiment, a two-layer sealing structure, namely a perfluoroether sealing ring 31 and a quartz packing sealing ring 32, is used to seal the sliding gap 10. Figure 3 and Figure 4 As shown, the inlet of the sliding gap 10 for high-temperature gas inflow is closer to the combustion chamber of the ramjet engine. Therefore, the side closer to the combustion chamber is the starting point for high-temperature gas leakage, and the quartz packing seal 32 is closer to this position than the perfluoroether seal 31. Thus, the overflowing high-temperature gas, after passing through the sliding gap 10, will first pass through the quartz packing seal 32. The quartz packing seal 32 has good high-temperature resistance and can withstand the heat of the high-temperature gas entering from the sliding gap 10 without damage. However, the quartz packing seal 32 has a woven structure and contains tiny pores, allowing a small amount of residual high-temperature gas to pass through the quartz packing seal 32 and re-enter the sliding gap 10, subsequently entering the perfluoroether seal 31. The perfluoroether sealing ring 31 has good resilience, and its sealing effect improves with increasing pressure. When a small amount of residual high-temperature gas enters the space containing the perfluoroether sealing ring 31, the pressure on the perfluoroether sealing ring 31 increases, causing it to fit more tightly against the outer wall of the compensating inner cylinder 2 and the inner wall of the compensating outer cylinder 1, thus preventing the residual high-temperature gas from escaping. Furthermore, the residual high-temperature gas has already passed through the quartz packing sealing ring 32 and the preceding sliding gap 10 for heat insulation, buffering, and throttling cooling, resulting in a significantly lower temperature by the time it reaches the perfluoroether sealing ring 31. Therefore, even though the high-temperature resistance of the perfluoroether sealing ring 31 is lower than that of the quartz packing sealing ring 32, its probability of damage is also lower. The combination of the perfluoroether sealing ring 31 and the quartz packing sealing ring 32 effectively reduces the leakage of high-temperature gas and extends the service life of the sealing assembly 3.

[0025] In a preferred embodiment, the compensator further includes a sealing ring 4, which is disposed at the other end of the compensating outer cylinder 1 and is fixedly connected to the compensating outer cylinder 1. A first mounting cavity is formed between the sealing ring 4, the outer wall surface of the compensating inner cylinder 2, and the inner wall surface of the compensating outer cylinder 1. A perfluoroether sealing ring 31 is disposed in the first mounting cavity, and the radial depth of the first mounting cavity is less than the diameter of the perfluoroether sealing ring 31 in its free state.

[0026] Specifically, such as Figure 1 and 2As shown, in this embodiment, the compensator also includes a sealing ring 4, which is fixed to the other end of the compensating outer cylinder 1 (i.e., the end away from the combustion chamber) by bolts. A first mounting cavity is formed between the sealing ring 4, the outer wall surface of the compensating inner cylinder 2, and the inner wall surface of the compensating outer cylinder 1. The first mounting cavity is annular and a perfluoroether sealing ring 31 is installed inside. Since the perfluoroether sealing ring 31 is an elastic sealing ring, and an elastic sealing ring must be compressed to produce elastic compression deformation and form continuous contact with the two side walls to achieve a sealing effect, the radial depth of the first mounting cavity is less than the cross-sectional diameter of the perfluoroether sealing ring in its free state, resulting in a radial compression of the perfluoroether sealing ring 31 after installation. In this embodiment, the radial compression of the perfluoroether sealing ring 31 is controlled at about 30%. When the compensating inner cylinder 2 and the compensating outer cylinder 1 slide relative to each other, the perfluoroether sealing ring 31 continuously adheres to the compensating inner cylinder 2, effectively preventing residual high-temperature gas from leaking into the external space.

[0027] In a preferred embodiment, an installation groove is provided on the outer wall surface of the compensation inner cylinder 2, and a second installation cavity is formed between the wall surface of the installation groove and the inner wall surface of the compensation outer cylinder 1. The quartz packing seal ring 32 is disposed in the second installation cavity, and the radial depth of the second installation cavity is less than the diameter of the quartz packing seal ring 32 in the free state.

[0028] Specifically, such as Figure 2 and Figure 3 As shown, an installation groove is formed on the outer wall of the compensating inner cylinder 2. The three walls of the installation groove and the inner wall of the compensating outer cylinder 1 enclose a second installation cavity, which is filled with a quartz packing ring 32. Similar to the perfluoroether sealing ring 31, the quartz packing ring 32 is also an elastic sealing ring. Therefore, the radial depth of the second installation cavity is smaller than the diameter of the quartz packing ring 32 in its free state, so that the quartz packing ring 32 can be in a compressed state after installation. In this embodiment, the radial compression of the quartz packing ring 32 is about 15-20%. The weaving density and radial compression of the quartz packing ring 32 can be determined by cold testing, with the standard being that the gas pressure in the sliding gap 10 between the quartz packing ring 32 and the perfluoroether sealing ring 31 reaches 30%-70% of the gas pressure in the compensating inner cylinder 2.

[0029] In a preferred embodiment, the compensator further includes a limiting member 7, which extends axially along the inner compensating cylinder 2, with one end fixedly connected to the sealing pressure ring 4 and the other end slidably connected to the inner compensating cylinder 2, for limiting the axial relative sliding stroke between the inner compensating cylinder 2 and the outer compensating cylinder 1.

[0030] Specifically, such as Figure 1As shown, in this embodiment, the compensator also includes a limiting member 7. The limiting member 7 is arranged parallel to the axis of the compensating inner cylinder 2. One end of the limiting member 7 is fixed to the sealing pressure ring 4 by bolts. A long groove extending along its own length is provided in the middle of the limiting member 7. A limiting pin extending radially outward along the outer wall of the compensating inner cylinder 2 is provided. The limiting pin is slidably assembled inside the long groove, thereby realizing the sliding connection between the limiting member 7 and the compensating inner cylinder 2. When the compensating inner cylinder 2 and the compensating outer cylinder 1 move away from each other, the limiting pin slides along the long groove to the side away from the combustion chamber. When the limiting pin contacts the groove wall at the end of the long groove away from the combustion chamber, the groove wall blocks the limiting pin from continuing to move, thereby locking the farthest distance of relative sliding between the compensating inner cylinder 2 and the compensating outer cylinder 1, preventing the compensating inner cylinder 2 from detaching from the compensating outer cylinder 1 due to excessive sliding and causing structural failure. When the inner compensating cylinder 2 and the outer compensating cylinder 1 approach each other, the limiting pin slides along the long groove towards the side closer to the combustion chamber until it abuts against the groove wall on that side, locking the minimum distance between the inner compensating cylinder 2 and the outer compensating cylinder 1 to prevent them from being unrestrictedly pressed together. In this embodiment, there are four limiting members 7, which are evenly distributed along the axial direction of the inner compensating cylinder 2. Each limiting member 7 corresponds to one limiting pin. The four sets of limiting structures work together synchronously to ensure that the inner compensating cylinder 2 and the outer compensating cylinder 1 remain coaxial during axial sliding, effectively preventing the inner compensating cylinder 2 and the outer compensating cylinder 1 from being relatively misaligned.

[0031] In a preferred embodiment, the compensator further includes an indicator 8, which is disposed on the outer wall surface of the inner compensator 2 and extends along the axial direction of the inner compensator 2. The indicator 8 is provided with a distance scale for slidingly engaging with the limiting member 7 to indicate the axial relative sliding amount between the inner compensator 2 and the outer compensator 1.

[0032] Specifically, such as Figure 1 As shown, in this embodiment, the compensator also includes an indicator 8, which is a displacement scale arranged along the axial direction of the inner compensator cylinder 2. The scale surface is printed with continuous distance graduations. The limiting member 7 can slide along the length direction of the indicator 8. The side of the limiting member 7 away from the combustion chamber can be used as a reading reference. When the inner compensator cylinder 2 moves closer to or further away from the outer compensator cylinder 1, the limiting member 7 slides along the indicator 8. By observing the corresponding position of the side of the limiting member 7 away from the combustion chamber and the graduations, the axial relative sliding amount between the inner compensator cylinder 2 and the outer compensator cylinder 1 can be directly obtained. The scale range of the displacement scale completely covers the allowable axial displacement range of the compensator, and warning lines are marked in the areas of the displacement scale near the travel limits at both ends. When the limiting member 7 slides to the position of the warning line, it means that the axial relative sliding amount between the inner compensator cylinder 2 and the outer compensator cylinder 1 has approached the safety threshold, so that maintenance personnel can identify the risk of overtravel in time, check for potential problems such as structural jamming and seal wear in advance, and improve the convenience and safety of thermal compensator operation monitoring.

[0033] In a preferred embodiment, the compensator further includes a detection component, which includes: Two temperature sensing elements 91 are respectively installed on the outer compensation cylinder 1 and the inner compensation cylinder 2, and are used to detect the temperature inside the outer compensation cylinder 1 and the inner compensation cylinder 2, respectively. Two pressure detection elements 92 are respectively installed on the outer compensation cylinder 1 and the inner compensation cylinder 2, and are used to detect the pressure inside the outer compensation cylinder 1 and the inner compensation cylinder 2.

[0034] Specifically, such as Figure 1 As shown, the detection assembly includes two temperature sensors 91 and two pressure sensors 92. Both temperature sensors 91 are armored K-type thermocouples, respectively mounted on the inner compensation cylinder 2 and the outer compensation cylinder 1. The temperature-sensing tip of the armored K-type thermocouple extends into the inner compensation cylinder 2 or the outer compensation cylinder 1 to collect the temperature of the gas inside the compensator. Its cold-end lead connects to an external data acquisition system via a high-temperature resistant connector for real-time temperature data reading. The two pressure sensors 92 are pressure sensors, connected to the internal flow channel of the compensator through pressure-sensing holes on the outer compensation cylinder 1 and the inner compensation cylinder 2, respectively. The diameter of the pressure-sensing holes is controlled between 0.5 and 1.5 mm. The orifice opening is flush with the inner wall of the outer compensation cylinder 1 or the inner compensation cylinder 2 and rounded to eliminate the disturbance of the flow field caused by the sharp corners of the orifice, avoid airflow turbulence and carbon deposit accumulation, and ensure the accuracy and stability of the pressure detection data. An external pressure-sensing pipe is connected to the outside of the pressure-sensing hole as a pressure transmission channel to transmit gas pressure to the pressure sensor. An insulation and protective structure can also be added to the outside of the pressure-sensing pipe to effectively prevent condensation from high-temperature gas cooling and pipe deformation due to heat. Furthermore, nitrogen can be used to periodically purge the pressure-sensing hole and pipe to regularly clean carbon deposits, dust, and impurities adhering to them, preventing blockage of the pressure-sensing channel and avoiding pressure detection failures and data distortion. By installing temperature detection element 91 and pressure detection element 92, the internal temperature and pressure distribution of the compensator can be monitored. When the compensator's operating condition is found to be abnormal based on temperature or pressure, the compensator can be repaired or the corresponding components replaced to avoid unexpected failures such as sudden leaks or structural failures. For example, if the temperature measured by temperature detection element 91 on the compensator outer cylinder 1 continues to rise and the pressure measured by pressure detection element 92 continues to fall, it can be determined that the quartz packing seal ring 32 or perfluoroether seal ring 31 is excessively worn or stuck, and the seal ring should be replaced promptly.

[0035] In a preferred embodiment, the inner wall of the compensating inner cylinder 2 is coated with a heat-insulating coating.

[0036] Specifically, in this embodiment, the inner wall of the compensating inner cylinder 2 is coated with a heat-insulating coating. The zirconia coating is prepared using a phase-change ablation composite material, such as yttrium-stabilized zirconia (YSZ) or zirconia-alumina multiphase ceramic material, both of which have extremely low thermal conductivity and high melting temperature. Under normal operating conditions, the heat-insulating coating acts as a static heat-insulating barrier, preventing high-temperature airflow from directly eroding the perfluoroether sealing ring 31 and the quartz packing sealing ring 32, thereby reducing the heat load borne by the two sealing rings. When extreme over-temperature conditions occur, the heat-insulating coating will preferentially undergo phase change, ablation, and decomposition. Through its own phase change and decomposition process, it actively absorbs a large amount of heat, at the cost of its own loss, to provide a longer safe working time for the perfluoroether sealing ring 31 and the quartz packing sealing ring 32, and to delay the failure rate of the perfluoroether sealing ring 31 and the quartz packing sealing ring 32.

[0037] In a preferred embodiment, at a reference temperature, the sliding gap 10 is greater than or equal to the limit gap threshold; the limit gap threshold is determined based on the expansion change of the compensator at the limit operating temperature calculated based on the reference temperature, the outer radius and linear expansion coefficient of the compensating inner cylinder 2 at the reference temperature, the inner radius and linear expansion coefficient of the compensating outer cylinder 1 at the reference temperature, the limit operating temperature of the compensator, and the safe gap threshold of the sliding gap 10 at the limit operating temperature.

[0038] Specifically, in this embodiment, the reference temperature refers to room temperature, which is also the temperature at which the inner compensating cylinder 2 and the outer compensating cylinder 1 are assembled. In this embodiment, it is taken as 20 degrees Celsius. When the inner compensating cylinder 2 and the outer compensating cylinder 1 are working, they will undergo radial thermal expansion synchronously due to the increase in temperature. If the sliding gap 10 is insufficient at room temperature, the radial expansion of the outer circle of the inner cylinder and the inner hole of the outer cylinder under high temperature conditions will squeeze each other and occupy the sliding space, further reducing the gap between the inner compensating cylinder 2 and the outer compensating cylinder 1. This can result in minor issues such as cylinder wall scraping and friction noise, or even serious issues such as the sliding structure seizing up and the overall thermal compensation expansion and contraction function of the compensator completely failing. Therefore, it is necessary to ensure that the sliding gap 10 at the reference temperature is greater than or equal to the limit gap threshold to reserve sufficient thermal expansion margin. In this way, even if the compensator is heated to the limit operating temperature and the inner compensating cylinder 2 and the outer compensating cylinder 1 undergo maximum radial expansion synchronously, the inner compensating cylinder 2 and the outer compensating cylinder 1 can still slide normally without jamming or seizing. The limit gap threshold is determined according to the following steps: First, the following parameters are obtained: reference temperature, the outer radius of the compensating inner cylinder 2 and its coefficient of linear expansion at the reference temperature, the inner radius of the compensating outer cylinder 1 and its coefficient of linear expansion at the reference temperature, the limit operating temperature of the compensator, and the required safety clearance threshold at the limit temperature. The reference temperature is 20 degrees Celsius. The outer radius of the compensating inner cylinder 2 and the inner radius of the compensating outer cylinder 1 at the reference temperature can be directly measured. The materials of the compensating inner cylinder 2 and the compensating outer cylinder 1 are determined, and their coefficients of linear expansion at the reference temperature can be obtained by referring to a table. In this embodiment, the limit operating temperature of the compensator is between 800 degrees Celsius and 800 degrees Celsius. The required safety clearance threshold at the limit temperature is typically taken as 0.01 mm to 0.02 mm.

[0039] Then, the total change in gap (i.e., expansion change) between the inner and outer compensation cylinders 2 and 1 due to dimensional changes when the temperature rises from the reference temperature to the ultimate operating temperature is calculated using formula (1): Formula (1) in, It represents the change in expansion. The outer radius of the inner cylinder is compensated at the reference temperature; The inner radius of the outer cylinder 1 is compensated at the reference temperature; To compensate for the linear expansion coefficient of the inner cylinder material; To compensate for the linear expansion coefficient of the outer cylinder material; Reference temperature; This is the maximum operating temperature.

[0040] Finally, based on the expansion change and the safety clearance threshold, the ultimate clearance threshold is calculated according to the following formula (2): Formula (2) in, This is the limit gap threshold; This is the safety gap threshold; This represents the change in expansion.

[0041] This invention utilizes the difference in thermal expansion deformation between the intake manifold and combustion chamber of a ramjet engine as the driving force. During the warm-up operation of the ramjet engine, axial elongation deformation occurs on both the combustion chamber side and the intake manifold side, driving the inner compensating cylinder 2 and the outer compensating cylinder 1 to slide relative to each other axially. This absorbs the difference in axial thermal deformation between the intake manifold and the combustion chamber, releases the thermal stress accumulated inside the structure, and avoids the defects of flange warping and bolt breakage that are prone to occur when the intake manifold and combustion chamber are directly connected. By setting a sliding gap 10 between the outer wall of the inner compensating cylinder 2 and the inner wall of the outer compensating cylinder 1 that meets the thermal expansion verification requirements, the sliding gap 10 at room temperature is guaranteed to be not less than the limit gap threshold, which can fully offset the difference in axial thermal expansion deformation between the inner compensating cylinder 2 and the outer compensating cylinder 1 under high temperature conditions. The reduction in clearance caused by the radial thermal expansion of cylinder 1 avoids risks such as cylinder expansion rubbing, sliding pair seizure, and failure of thermal compensation function. At the same time, a double sealing structure is formed by the high-temperature resistant quartz packing seal 32 and the high-resilience perfluoroether seal 31. The quartz packing seal 32 is used to block high-temperature gas in the front while the perfluoroether seal 31 seals the residual leakage medium, which improves the sealing performance of the compensator. The overall structure takes into account the high-temperature anti-seizure sliding capability and long-term sealing reliability, and is suitable for the service conditions of high-speed aircraft ramjet engines that are in high temperature for a long time. It effectively solves the defects of rigid connection that is prone to warping and leakage and bellows that are prone to creep and cracking, and improves the high-temperature durability and sealing performance of thermal matching compensator.

[0042] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. The above descriptions are only preferred embodiments of the present invention. It should be noted that due to the limitations of textual expression, and the objective existence of infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of the present invention, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of the present invention.

Claims

1. A thermal matching compensator for high-speed aircraft, characterized in that, include: The compensation outer cylinder (1) is hollow inside, and one end of the compensation outer cylinder (1) is connected to the combustion chamber of the ramjet engine; The inner compensating cylinder (2) extends into the outer compensating cylinder (1) from the other end of the outer compensating cylinder (1) and slides with the outer compensating cylinder (1). The end of the inner compensating cylinder (2) away from the outer compensating cylinder (1) is connected to the air intake corresponding to the ramjet engine. A sliding gap (10) is provided between the outer wall surface of the inner compensating cylinder (2) and the inner wall surface of the outer compensating cylinder (1). A sealing assembly (3) is disposed between the outer wall surface of the compensating inner cylinder (2) and the inner wall surface of the compensating outer cylinder (1), including a perfluoroether sealing ring (31) and a quartz packing sealing ring (32) spaced apart along the axial direction of the compensating inner cylinder (2), the perfluoroether sealing ring (31) and the quartz packing sealing ring (32) are used to cooperate with each other to seal the sliding gap (10).

2. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, The quartz packing seal (32) is located on the side of the perfluoroether seal (31) near the combustion chamber of the ramjet engine.

3. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, The compensator also includes a sealing ring (4), which is disposed at the other end of the compensating outer cylinder (1) and is fixedly connected to the compensating outer cylinder (1). A first mounting cavity is formed between the sealing ring (4), the outer wall surface of the compensating inner cylinder (2), and the inner wall surface of the compensating outer cylinder (1). The perfluoroether sealing ring (31) is disposed in the first mounting cavity, and the radial depth of the first mounting cavity is less than the diameter of the perfluoroether sealing ring (31) in the free state.

4. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, An installation groove is provided on the outer wall surface of the compensation inner cylinder (2). A second installation cavity is formed between the wall surface of the installation groove and the inner wall surface of the compensation outer cylinder (1). The quartz packing seal (32) is disposed in the second installation cavity, and the radial depth of the second installation cavity is less than the diameter of the quartz packing seal (32) in the free state.

5. The thermal matching compensator for high-speed aircraft according to claim 3, characterized in that, The compensator also includes a limiting member (7), which extends axially along the inner compensator cylinder (2), with one end fixedly connected to the sealing pressure ring (4) and the other end slidably connected to the inner compensator cylinder (2), for limiting the axial relative sliding stroke between the inner compensator cylinder (2) and the outer compensator cylinder (1).

6. The thermal matching compensator for high-speed aircraft according to claim 5, characterized in that, The compensator also includes an indicator (8), which is disposed on the outer wall surface of the inner compensator (2) and extends along the axial direction of the inner compensator (2). The indicator (8) is provided with a distance scale for sliding cooperation with the limiting member (7) to indicate the axial relative sliding amount between the inner compensator (2) and the outer compensator (1).

7. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, The compensator further includes a detection component, which includes: Two temperature detection elements (91) are respectively installed on the outer compensation cylinder (1) and the inner compensation cylinder (2) and are used to detect the temperature inside the outer compensation cylinder (1) and the inner compensation cylinder (2); Two pressure detection elements (92) are respectively installed on the outer compensation cylinder (1) and the inner compensation cylinder (2) and are used to detect the pressure inside the outer compensation cylinder (1) and the inner compensation cylinder (2).

8. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, The inner wall of the compensation inner cylinder (2) is coated with a heat-insulating coating.

9. The thermal matching compensator for high-speed aircraft according to claim 1, characterized in that, At the reference temperature, the sliding clearance (10) is greater than or equal to the limit clearance threshold; the limit clearance threshold is determined based on the expansion change of the compensator at the limit operating temperature calculated based on the reference temperature, the outer radius and linear expansion coefficient of the compensating inner cylinder (2) at the reference temperature, the inner diameter and linear expansion coefficient of the compensating outer cylinder (1) at the reference temperature, the limit operating temperature of the compensator, and the safety clearance threshold of the sliding clearance (10) at the limit operating temperature.

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