A porous divergent cooling structure for a combustion chamber wall

Abstract

The utility model discloses a kind of porous divergent cooling structures of combustion chamber wall, belong to the technical field of aero-engine heat protection, including shell, combustion chamber and fixed at the heat dissipation component of combustion chamber outer wall, the heat dissipation component is equipped with first divergent hole and second divergent hole, the combustion chamber outer wall is also provided with adjusting component, the adjusting component includes sensor, rotating ring, spring, receiving plate, receiving ring, cover plate and rotating rod, the sensor monitors temperature to drive rotating ring rotation, the rotating ring is moved by rotating rod cover plate, the cover plate one end is rotatably connected with receiving ring, the other end is slid in the guide slot of receiving plate by rotating shaft, the spring provides reset force for rotating ring.The utility model can be self-adaptingly adjusted local cooling according to working condition, ensure temperature field uniform, save cooling gas amount, improve the thermal efficiency and reliability of engine.

Description

Technical Field

[0001] This utility model relates to the field of thermal protection technology for aero-engines, and in particular to a porous radiating cooling structure for the combustion chamber wall. Background Technology

[0002] The combustion chamber of an aircraft engine is one of its core components, enduring an extremely high-temperature combustion gas environment. To ensure the safe and reliable operation of the combustion chamber structure at high temperatures, efficient cooling of its walls is essential. Divergent cooling (or porous cooling) is one of the widely adopted efficient thermal protection technologies. It involves setting numerous tiny cooling holes on the combustion chamber wall, allowing the cooling medium (usually compressor bleed air) to seep out from the wall, forming a uniform and continuous cooling gas film on the high-temperature side of the wall, thereby effectively isolating the wall from the high-temperature combustion gas.

[0003] In existing technical solutions, structures used to achieve radiative cooling typically employ fixed pore sizes, porosity, and pore distribution. Once the design is finalized and manufactured, the flow capacity and flow distribution pattern of the cooling gas are fixed.

[0004] However, in actual operation, the engine's operating conditions (such as starting, cruising, acceleration, and full load) are complex and varied. Under different operating conditions, the temperature field distribution and local heat load inside the combustion chamber will change significantly. The design of a fixed radiator structure often needs to take into account the highest heat load conditions to ensure a cooling safety margin under extreme conditions. This results in the cooling components still delivering an excessive amount of cooling gas (relative to the current operating condition) when the engine is in cruising or low load conditions.

[0005] This cooling method lacks adaptive adjustment capability. Excessive consumption of cooling gas unnecessarily increases the engine's bleed air volume, which could have been used for power generation; its excessive consumption directly reduces the engine's overall thermal efficiency and thrust performance. Therefore, how to accurately and dynamically allocate cooling gas flow according to the real-time, localized thermal load state of the combustion chamber walls has become a core technical problem that existing divergent cooling structures urgently need to solve.

[0006] Therefore, this invention proposes a porous radiating cooling structure for the combustion chamber wall to address the shortcomings of the prior art. Utility Model Content

[0007] To overcome the above shortcomings, this utility model provides a porous divergent cooling structure for the combustion chamber wall, aiming to improve the existing technology where the porous divergent cooling structure for the combustion chamber wall has a fixed cooling hole diameter and flow rate, which cannot be adaptively adjusted according to changes in engine operating conditions or local thermal load conditions, resulting in high cooling gas consumption and low thermal protection efficiency.

[0008] To achieve the above objectives, this utility model provides a porous radiating cooling structure for the combustion chamber wall, comprising: a shell, a combustion chamber disposed inside the shell, and a heat dissipation assembly fixedly connected to the outer wall of the combustion chamber, wherein a first radiating hole and a second radiating hole are provided through the surface of the heat dissipation assembly; and an adjustment assembly disposed on the outer wall of the combustion chamber.

[0009] The adjustment assembly includes a sensor, a rotating ring, a spring, a receiving plate, a rotating shaft, a receiving ring, a cover plate, and a rotating rod.

[0010] The sensor is fixedly installed on the wall of the combustion chamber. The rotating ring is rotatably sleeved on the outer periphery of the combustion chamber. The receiving plate and the receiving ring are both fixedly installed on the outer wall of the combustion chamber. One end of the cover plate is rotatably connected to the receiving ring. A guide groove is formed on the inner wall of the receiving plate. The rotating shaft is fixedly connected to the other end of the cover plate, and the rotating shaft is slidably fitted within the guide groove of the receiving plate. One end of the rotating rod is hinged to the rotating ring, and the other end of the rotating rod is hinged to the cover plate. The cover plate is positioned above the second divergence hole, and the projected area of ​​the cover plate covers the second divergence hole.

[0011] Preferably, one end of the spring is fixedly connected to the rotating ring, and the other end of the spring is fixedly connected to the outer wall of the combustion chamber.

[0012] Preferably, a cooling cavity is formed inside the heat dissipation component, and a filter screen is provided inside the heat dissipation component and on the air intake side located at the first radiating hole and the second radiating hole.

[0013] Preferably, a heat sink is fixedly connected to the outer wall of the housing, and the heat sink is spirally wound around the outer periphery of the housing.

[0014] Preferably, the surface of the housing is provided with an air inlet hole, which penetrates the wall thickness of the housing.

[0015] Preferably, the first and second radiating holes are staggered on the surface of the heat dissipation component.

[0016] Preferably, the cover plate has an arc-shaped plate structure, and the inner arc surface of the cover plate is in contact with the outer surface of the heat dissipation component.

[0017] Preferably, the probe portion of the sensor passes through the heat dissipation assembly and extends into the interior of the combustion chamber.

[0018] This utility model has the following beneficial effects: 1. In this utility model, by setting an adjustment component on the combustion chamber wall, using sensors to monitor the wall temperature or airflow parameters in real time, and by rotating a ring and a rod to drive the cover plate to rotate above the second radiating hole to change the shielding area, the problem of the fixed radiating hole structure in the prior art being unable to adaptively adjust according to engine operating condition switching or local abnormal temperature rise, resulting in insufficient cooling leading to ablation or excessive cooling causing gas waste, is solved. This achieves closed-loop, dynamic, and precise control of cooling flow, ensuring a uniform and stable temperature field on the combustion chamber wall while maximizing the saving of high-pressure cooling air resources and improving the overall thermal efficiency and reliability of the engine.

[0019] 2. This utility model solves the problems of weak external thermal protection and low heat transfer efficiency caused by relying solely on internal air film cooling in the prior art by setting spirally wound heat dissipation fins on the outer wall of the shell and working in conjunction with the internal heat dissipation components. It significantly increases the heat exchange surface area between the shell and the external environment, and guides the external airflow to form a spiral flow path to improve turbulence and convective heat transfer efficiency. Thus, it constructs a three-dimensional thermal protection system that combines internal divergent cooling and external convective heat dissipation, effectively reducing the thermal stress of the structure. Attached Figure Description

[0020] Figure 1 This is a perspective view of a porous radiating cooling structure for the combustion chamber wall proposed in this utility model; Figure 2 This is a schematic diagram of a combustion chamber with a porous radiating cooling structure for the combustion chamber wall, as proposed in this utility model. Figure 3 This is a schematic diagram of the rotating ring of a porous radiating cooling structure for the combustion chamber wall proposed in this utility model; Figure 4 This is a schematic diagram of a cover plate for a porous radiating cooling structure on the combustion chamber wall proposed in this utility model; Figure 5 This is a schematic diagram of a filter screen for a porous radiating cooling structure on the combustion chamber wall proposed in this utility model.

[0021] Legend: 1. Housing; 2. Heat sink; 3. Combustion chamber; 4. Air inlet; 5. Adjustment assembly; 501. Sensor; 502. Rotating ring; 503. Spring; 504. Support plate; 505. Rotating shaft; 506. Support ring; 507. Cover plate; 508. Rotating rod; 6. Heat dissipation assembly; 601. First vent; 602. Filter screen; 603. Second vent. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Reference Figures 1-5 This utility model provides a porous divergent cooling structure for the combustion chamber wall, which aims to solve the problem that the existing combustion chamber cooling structure cannot adaptively adjust the cooling flow according to the operating conditions, resulting in low thermal protection efficiency and wasted gas volume.

[0024] Specifically, it includes a housing 1 and a combustion chamber 3 disposed inside the housing 1. A heat dissipation component 6 is fixedly connected to the outer wall of the combustion chamber 3. A first divergence hole 601 and a second divergence hole 603 are opened through the surface of the heat dissipation component 6 to achieve porous divergence cooling of the wall of the combustion chamber 3. In order to cooperate with the introduction of internal cooling airflow, an air inlet hole 4 is opened on the surface of the housing 1 to penetrate its wall thickness. External high-pressure air enters the gap between the housing 1 and the combustion chamber 3 through the air inlet hole 4, and then is ejected through the holes on the heat dissipation component 6 to form a cooling air film.

[0025] An adjustment component 5 is also provided on the outer wall of the combustion chamber 3. The adjustment component 5 works in conjunction with the heat dissipation component 6 to achieve closed-loop variable flow control. Specifically, the adjustment component 5 includes a sensor 501, a rotating ring 502, a spring 503, a receiving plate 504, a rotating shaft 505, a receiving ring 506, a cover plate 507, and a rotating rod 508. The sensor 501 is fixedly installed on the wall of the combustion chamber 3 to monitor local temperature changes in real time. The rotating ring 502 is rotatably sleeved on the outer periphery of the combustion chamber 3 as the drive transmission ring for the entire adjustment action. The receiving plate 504 and the receiving ring 506 are both fixedly installed on the outer wall of the combustion chamber 3 to provide structural support and positioning.

[0026] One end of the cover plate 507 is rotatably connected to the receiving ring 506, allowing the cover plate 507 to deflect around this connection point. To limit and guide the movement trajectory of the cover plate 507, a guide groove is provided on the inner wall of the receiving plate 504. The other end of the cover plate 507 is fixedly connected to a rotating shaft 505, which slides within the guide groove of the receiving plate 504. Meanwhile, one end of the rotating rod 508 is hinged to the rotating ring 502, and the other end of the rotating rod 508 is hinged to the cover plate 507, thus forming a linkage mechanism in which "the rotating ring 502 rotates to drive the rotating rod 508, thereby pushing and pulling the cover plate 507 to deflect under the constraint of the receiving ring 506 and the receiving plate 504". The cover plate 507 is positioned above the second divergence hole 603, and its projected area covers the second divergence hole 603. The deflection movement of the cover plate 507 changes its blocking area on the second divergence hole 603, thereby adjusting the flow rate of the cooling gas.

[0027] To ensure the stability and reset function of the adjustment structure, one end of the spring 503 is fixedly connected to the rotating ring 502, and the other end of the spring 503 is fixedly connected to the outer wall of the combustion chamber 3. The elastic potential energy of the spring 503 provides a reset force and balance support for the rotating ring 502.

[0028] To ensure the cleanliness of the jet airflow and prevent the holes from becoming clogged, a cooling chamber is formed inside the heat dissipation assembly 6, and a filter screen 602 is provided on the air inlet side of the first radiating hole 601 and the second radiating hole 603. The cooling gas must pass through the filter screen 602 to filter impurities before entering the radiating hole.

[0029] To enhance external heat dissipation of the housing 1, a heat sink 2 is fixedly connected to the outer wall of the housing 1. The heat sink 2 is spirally wound around the outer periphery of the housing 1. By increasing the heat exchange area and guiding the external airflow in a spiral flow, the convective heat transfer efficiency is improved. In addition, the first diverging hole 601 and the second diverging hole 603 are staggered on the surface of the heat dissipation component 6 to optimize the uniformity of the air film. The cover plate 507 has an arc-shaped plate structure and its inner arc surface is attached to the outer surface of the heat dissipation component 6 to ensure the sealing and adjustment effect. The probe part of the sensor 501 passes through the heat dissipation component 6 and extends into the interior of the combustion chamber 3 to directly obtain more accurate furnace temperature data.

[0030] Working principle: During the operation of the aero-engine, external air is compressed by the compressor and enters the casing 1 through the air inlet 4. The high-pressure gas is divided into two parts. One part enters the combustion chamber 3 and mixes with fuel for combustion to generate high-temperature, high-energy gas to drive the turbine. The other part serves as cooling gas and enters the cooling chamber through the gap between the casing 1 and the combustion chamber 3 to cool the wall of the combustion chamber 3. The cooling gas is first filtered by the filter screen 602 to remove impurities and then enters the heat dissipation assembly 6. It is then ejected through the first divergence hole 601 and the second divergence hole 603, respectively acting on the combustion chamber wall 3 and the liner surface to form a uniform and continuous cold film layer, thereby isolating the direct radiation and scouring of the high-temperature gas and achieving efficient cooling of the combustion chamber 3 wall.

[0031] When an abnormal increase in local temperature of the combustion chamber wall 3 or liner is detected, or when the engine operating condition changes, the regulating component 5 initiates closed-loop adjustable cooling control. Sensor 501 monitors the temperature and airflow parameters of the combustion chamber wall 3 in real time. The rotating ring 502 rotates, driving the cover plate 507. The rotating shaft 505 slides on the inner wall of the receiving plate 504, and the cover plate 507 can rotate about the rotating shaft 505. One end of the cover plate 507 is connected to the receiving ring 506. The rotation of the rotating rod 508 drives the cover plate 507 to interact with the receiving ring. One end of 506 is connected to a shaft for rotation, while the other end slides in a groove on the inner wall of the receiving plate 504. This movement process can change the obstruction of the second radiating hole 603 by multiple rotating rods 508, thereby changing the cooling gas flow rate and the heat dissipation effect. Automatic adjustment can be achieved through sensor 501, so that the internal temperature of the equipment remains stable, avoiding overheating and material waste. During operation, spring 503 provides reset force and balance support, and receiving plate 504 and receiving ring 506 provide mechanical support and positioning.

[0032] When the engine is under continuous high load or steady-state high temperature, the heat dissipation component 6 works together with the heat dissipation fins 2 and the housing 1 to form a stable and efficient heat exchange path. The cooling air flows inside the housing 1 after passing through the first radiating hole 601 and being purified by the filter screen 602. The heat dissipation fins 2, together with the housing 1 and the heat dissipation component 6, constitute a highly efficient heat conduction. Furthermore, the spiral structure of the heat dissipation fins 2 can significantly increase the heat exchange surface area in a limited space, optimize the flow velocity distribution, and achieve continuous cooling and thermal balance control of the combustion chamber 3 wall, thereby comprehensively improving the engine's thermal protection performance and reliability.

Claims

1. A porous radiating cooling structure for the combustion chamber wall, comprising: The combustion chamber (3) is located inside the housing (1). A heat dissipation component (6) is fixedly connected to the outer wall of the combustion chamber (3). A first radiating hole (601) and a second radiating hole (603) are provided through the surface of the heat dissipation component (6). The outer wall of the combustion chamber (3) is further provided with an adjustment component (5). The adjustment assembly (5) includes a sensor (501), a rotating ring (502), a spring (503), a receiving plate (504), a rotating shaft (505), a receiving ring (506), a cover plate (507), and a rotating rod (508). The sensor (501) is fixedly installed on the wall of the combustion chamber (3). The rotating ring (502) is rotatably sleeved on the outer periphery of the combustion chamber (3). The receiving plate (504) and the receiving ring (506) are both fixedly installed on the outer wall of the combustion chamber (3). One end of the cover plate (507) is connected to the receiving ring (506). The receiving plate (504) is rotatably connected to the inner wall of the receiving plate (504), and the rotating shaft (505) is fixedly connected to the other end of the covering plate (507). The rotating shaft (505) is slidably fitted in the guiding groove of the receiving plate (504). One end of the rotating rod (508) is hinged to the rotating ring (502), and the other end of the rotating rod (508) is hinged to the covering plate (507). The covering plate (507) is located above the second diverging hole (603), and the projected area of ​​the covering plate (507) covers the second diverging hole (603).

2. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, One end of the spring (503) is fixedly connected to the rotating ring (502), and the other end of the spring (503) is fixedly connected to the outer wall of the combustion chamber (3).

3. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, A cooling chamber is formed inside the heat dissipation component (6), and a filter screen (602) is provided inside the heat dissipation component (6) and on the air intake side of the first radiating hole (601) and the second radiating hole (603).

4. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, A heat sink (2) is fixedly connected to the outer wall of the housing (1), and the heat sink (2) is spirally wound around the outer periphery of the housing (1).

5. The porous radiating cooling structure for the combustion chamber wall according to claim 4, characterized in that, An air inlet (4) is provided on the surface of the housing (1), and the air inlet (4) penetrates the wall thickness of the housing (1).

6. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, The first radiating hole (601) and the second radiating hole (603) are staggered on the surface of the heat dissipation assembly (6).

7. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, The cover plate (507) has an arc-shaped plate structure, and the inner arc surface of the cover plate (507) is attached to the outer surface of the heat dissipation component (6).

8. The porous radiating cooling structure for the combustion chamber wall according to claim 1, characterized in that, The probe portion of the sensor (501) passes through the heat dissipation assembly (6) and extends into the interior of the combustion chamber (3).

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