Combustion chamber and auxiliary power unit having the same
By designing the inner and outer casing components and utilizing a combination of flexible and rigid materials, the problem of fragments penetrating the combustion chamber when the turbine disc breaks was solved, reducing engine weight and heat transfer, and improving the safety and reliability of the combustion chamber.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AECC HUNAN AVIATION POWERPLANT RES INST
- Filing Date
- 2026-03-06
- Publication Date
- 2026-06-12
AI Technical Summary
When the turbine disc breaks, the high-speed debris often punctures the combustion chamber, causing damage to pipes and wiring, increasing engine weight and manufacturing costs. At the same time, high-temperature heat transfer leads to aging and failure of pipes and wiring.
The design employs an inner and outer casing assembly. The inner casing assembly includes an inner casing body, baffle, inner containment layer, and inner containment ring. The outer casing assembly includes an outer casing body, heat insulation layer, and outer containment layer. Through a combination of flexible and rigid materials, it prevents debris from flying out and reduces heat transfer.
It effectively prevents debris from penetrating the combustion chamber, reduces kinetic energy damage, lowers engine weight and cost, and prevents high-temperature aging, thereby improving safety and reliability.
Smart Images
Figure CN122190853A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aero-engine technology, and more specifically to a combustion chamber and an auxiliary power unit having therein. Background Technology
[0002] When an engine is running, the combustion chamber receives high-pressure air from the compressor and mixes it with aviation kerosene from the fuel system to produce high-temperature combustion gases, which are then supplied to the turbine for power conversion. As one of the core components of the engine, the combustion chamber connects to the compressor at the front end to receive the high-pressure air, and connects to the turbine at the rear end to supply it with high-temperature combustion gases. Therefore, the combustion chamber needs sufficient rigidity and strength reserves. The engine is installed inside the aircraft nacelle, with a complex network of pipes and wiring externally. When the engine rotor fails, the combustion chamber, as one of the outermost components of the engine, needs to be able to withstand high-speed debris. Therefore, the combustion chamber needs sufficient flexibility and containment capacity. Existing combustion chambers often only consider the strength of the combustion chamber itself. When the turbine disc ruptures or malfunctions, high-speed debris often penetrates the combustion chamber, destroys pipes and wiring, damages the aircraft nacelle, and causes fuel and lubricating oil to splash and ignite inside the nacelle. To prevent debris from penetrating the combustion chamber casing, the casing is often locally thickened to 5 to 6 times its original thickness. However, this measure greatly increases the weight of the engine and significantly raises manufacturing costs. Summary of the Invention
[0003] In view of this, the present invention provides a combustion chamber and an auxiliary power device having the same, to solve the problem of debris penetrating the combustion chamber.
[0004] In a first aspect, the present invention provides a combustion chamber, comprising:
[0005] Outer casing assembly; An inner casing assembly is connected to the outer casing assembly at one end. The inner casing assembly has a gas flow channel on its inner side. The inner casing assembly includes, in radial outward direction, an inner casing body, a baffle, an inner containment layer, and an inner containment ring. The inner containment layer is flexible, while the baffle and the inner containment ring are made of rigid materials. A flame tube is disposed between the outer casing assembly and the inner casing assembly, and is connected to the gas flow channel; A fuel nozzle, connected to the fuel main, passes through the outer casing assembly and extends into the flame tube; A compressor diffuser is located at the end of the outer casing assembly furthest from the fuel nozzle; The turbine rotor has blades located in the gas flow channel.
[0006] Beneficial effects: When the engine is running, high-pressure air enters the combustion chamber through the passage between the compressor diffuser and the outer casing assembly, and then enters the flame tube. Fuel enters multiple fuel nozzles from the fuel main and is injected into the flame tube. Inside the flame tube, the high-pressure air and fuel mix and burn, releasing heat to form high-temperature gas (greater than 1300°C). This high-temperature gas flows into the gas flow channel, impacting the turbine rotor blades and causing them to rotate at high speed and perform work. The high-temperature gas entering the gas flow channel impacts the turbine rotor, causing it to rotate at high speed and perform work, with a maximum speed of nearly 80,000 rpm. Under abnormal conditions, the entire turbine rotor or disc may break. The inner casing assembly, radially outward, comprises an inner casing body, a baffle, an inner containment layer, and an inner containment ring. The inner containment layer is flexible, while the baffle and inner containment ring are made of rigid materials. High-speed turbine disc debris will penetrate the inner casing body and baffle, and come into contact with the inner containment layer. The inner containment layer has a certain degree of elasticity and tensile strength. When high-speed debris contacts the inner containment layer, it effectively reduces the kinetic energy of the debris, containing small debris or blades within it to prevent damage to the combustor. When the high-speed debris is a large piece of turbine disc, the inner containment layer may be damaged. The inner containment ring, located outside the inner containment layer, can further prevent debris or turbine discs from flying out and damaging the combustor. The inner containment layer and inner containment ring work together to effectively prevent debris from flying out and penetrating the combustion chamber.
[0007] In one alternative embodiment, the thickness of the inner containment ring at the position corresponding to the turbine rotor is greater than the thickness at other positions.
[0008] Beneficial effects: The thickness of the inner containment ring at the position corresponding to the turbine rotor is greater than that at other positions. The inner containment ring and the inner containment layer work together to prevent debris from flying out, while avoiding excessive overall thickness of the inner casing assembly, which would lead to excessive engine weight and save costs.
[0009] In one optional embodiment, the inner casing body includes a main body and a first connecting part disposed at one end of the main body. The first connecting part is connected to the outer casing assembly. Multiple bosses are provided at circumferential intervals at both ends of the main body. The two ends of the baffle, the inner containment layer and the inner containment ring are fixed to the bosses.
[0010] Beneficial effects: By setting multiple protrusions at circumferential intervals at both ends of the main body, the two ends of the baffle, inner enclosure layer and inner enclosure ring are fixed to the protrusions, and a cooling space is formed between the baffle and the main body. High-pressure air can enter the cooling space through the gap between two adjacent protrusions to cool the turbine rotor.
[0011] In one optional embodiment, the boss is provided with a bolt hole for the body, the baffle is provided with a baffle through hole corresponding to the bolt hole for the body, and a U-shaped groove is provided outside the baffle through hole. The inner containing layer is formed by a rope wrapped around the outside of the baffle, and the two ends of the rope are embedded in the U-shaped groove. The inner containing ring is provided with a bolt through hole corresponding to the baffle through hole. Fasteners pass through the bolt through hole and the baffle through hole and are fastened to the bolt hole for the body.
[0012] Beneficial effects: The boss has bolt holes for the body, and the baffle has through holes corresponding to these bolt holes. A U-shaped groove is provided outside the through holes. The inner containment layer is formed by a rope wrapped around the baffle, with both ends of the rope embedded in the U-shaped groove. The inner containment ring has bolt holes corresponding to the through holes in the baffle. Fasteners pass through the bolt holes and the through holes in the baffle and are tightened into the bolt holes in the body. While fixing the baffle and the inner containment ring to the inner casing, the fasteners also press the inner containment layer against the baffle, locking both ends of the rope in the U-shaped groove. The inner containment layer, formed by the rope wrapped around the baffle, has a certain degree of elasticity and tensile strength. When high-speed debris contacts the inner containment layer, the rope deforms to enclose the debris. Simultaneously, the individual ropes possess good tensile strength, effectively reducing the kinetic energy of the debris and containing small debris or blades within the inner containment layer, preventing damage to the flame tube.
[0013] In one optional embodiment, the main body is provided with a rear cooling hole, a middle cooling hole, and a front cooling hole of the inner casing at axial intervals, and the rear cooling hole, the middle cooling hole, and the front cooling hole penetrate the main body radially.
[0014] Beneficial effects: The main body is provided with an inner casing rear cooling hole, an inner casing middle cooling hole and an inner casing front cooling hole at intervals along its axial direction. The inner casing rear cooling hole, inner casing middle cooling hole and inner casing front cooling hole penetrate the main body radially. High-pressure air can enter the cooling space between the baffle and the main body through the gap between two adjacent bosses, and then enter the interior of the gas flow channel through the inner casing rear cooling hole, inner casing middle cooling hole and inner casing front cooling hole to cool the turbine rotor.
[0015] In one optional embodiment, the outer casing assembly includes an outer casing body, a heat insulation layer, an outer casing, and a nozzle mounting seat. The outer casing body is connected to the end of the inner casing body. The nozzle mounting seat passes through the outer casing body, the heat insulation layer, and the outer casing. The nozzle mounting seat has a nozzle mounting hole through which the fuel nozzle passes.
[0016] Beneficial effects: Since the temperature of high-pressure air is usually greater than 400℃, the high-pressure air is in direct contact with the outer casing of the outer casing assembly, heating the outer casing through convection and radiation heat transfer. The high-temperature gas heats the outer casing through radiation heat transfer during its flow. These two forms of heat transfer cause the temperature of the outer casing to rise significantly. By setting up a heat insulation layer, the heat insulation layer can prevent the outer casing from transferring heat to the outer shell, effectively reducing the temperature of the outer shell and preventing the pipes and lines arranged on the outside of the outer shell from aging and failing due to high temperature.
[0017] In one optional embodiment, the insulation layer is made of microporous composite cotton.
[0018] Beneficial effects: The insulation layer is made of microporous composite cotton, which is composed of silicon dioxide, microparticles, metal oxides and short fibers. The stacking of fibers creates a large number of micropores inside, which has a low thermal conductivity and good temperature resistance. Therefore, it can effectively block the heat from the outer casing from being transferred to the outer shell, thus effectively reducing the temperature of the outer shell and preventing the pipes and lines arranged on the outside of the outer shell from aging and failing at high temperatures.
[0019] In one alternative embodiment, the outer casing assembly further includes an outer containment layer disposed between the thermal insulation layer and the outer casing, the outer containment layer being flexible.
[0020] Beneficial effects: High-temperature gas impacts the turbine rotor, causing it to rotate at high speed and perform work, with a maximum speed of nearly 80,000 rpm. In abnormal situations, the entire turbine rotor or disc may rupture. High-speed flying debris will penetrate the inner casing and baffles and come into contact with the inner containment layer. The inner containment layer has certain elasticity and tensile strength. When high-speed flying debris comes into contact with the inner containment layer, it can effectively reduce the kinetic energy of the debris and contain small debris or blades inside the inner containment layer to prevent damage to the flame tube. When the high-speed flying debris is a large piece of turbine disc, the inner containment layer may be damaged. The inner containment ring set outside the inner containment layer can further prevent debris or turbine disc from flying out and damaging the flame tube. When the disc passes through the containment ring, breaks the flame tube, and reaches the outer casing assembly, since the outer casing assembly includes an outer containment layer located between the heat insulation layer and the outer casing, the outer containment layer is flexible. The outer containment layer can wrap the flying disc by deformation, which can effectively reduce the kinetic energy of the disc and contain it inside the outer containment layer to prevent damage to external pipelines and wiring.
[0021] In one alternative embodiment, the outer containment layer is formed by wrapping a rope around the outside of the insulation layer.
[0022] Beneficial effects: The outer containment layer is formed by the rope wrapped around the insulation layer. When the high-speed flying disc comes into contact with the containment layer, the outer containment layer deforms and wraps the flying disc. At the same time, the single rope has good tensile strength, which can effectively reduce the kinetic energy of the disc and wrap it inside the outer containment layer to prevent damage to external pipes and lines.
[0023] Secondly, the present invention also provides an auxiliary power device having a combustion chamber, comprising: The combustion chamber. Attached Figure Description
[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0025] Figure 1 This is a cross-sectional view of a combustion chamber according to an embodiment of the present invention; Figure 2 for Figure 1 A cross-sectional view of the outer casing assembly shown; Figure 3 This is a sectional view of the outer casing. Figure 4 for Figure 1 A cross-sectional view of the inner casing assembly shown; Figure 5 This is a schematic diagram of the inner casing. Figure 6 A schematic diagram showing an inner enclosure layer installed on the outside of the baffle; Figure 7 for Figure 6 Enlarged view of point A in the middle; Figure 8 This is a schematic diagram of an inner enclosing ring; Figure 9 This is a schematic diagram of a combustion chamber according to an embodiment of the present invention; Figure 10 This is a schematic diagram of a combustion chamber according to an embodiment of the present invention.
[0026] Explanation of reference numerals in the attached figures: 10. Outer casing assembly; 11. Outer casing body; 111. Third connecting part; 112. Nozzle orifice; 113. Second connecting part; 114. Inner shell; 12. Outer shell; 13. Nozzle mounting base; 131. Nozzle mounting hole; 132. Mounting edge; 14. Heat insulation layer; 15. Outer enclosure layer; 20. Inner casing assembly; 21. Inner casing body; 211. Boss; 212. Body bolt hole; 213. First connecting part; 214. Rear cooling hole of inner casing; 215. Middle cooling hole of inner casing; 216. Front cooling hole of inner casing; 22. Baffle; 221. Through hole of baffle; 222. U-shaped groove; 23. Gasket; 24. Fastener; 25. Inner enclosure ring; 251. Bolt through hole; 26. Inner enclosure layer; 30. Fuel injector; 40. Fuel main; 50. Flame tube; 51. Outer ring main combustion port; 52. Outer ring intermediate port; 53. Outer ring mixing port; 54. Inner ring main combustion port; 55. Inner ring intermediate port; 56. Inner ring mixing port; 60. Compressor diffuser; 70. Turbine rotor. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0030] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0031] When an engine is running, the combustion chamber receives high-pressure air from the compressor and mixes it with aviation kerosene from the fuel system to produce high-temperature combustion gases, which are then supplied to the turbine for power conversion. As one of the core components of the engine, the combustion chamber connects to the compressor at the front end to receive the high-pressure air, and connects to the turbine at the rear end to supply it with high-temperature combustion gases. Therefore, the combustion chamber needs sufficient rigidity and strength reserves. The engine is installed inside the aircraft nacelle, with a complex network of pipes and wiring externally. When the engine rotor fails, the combustion chamber, as one of the outermost components of the engine, needs to be able to withstand high-speed debris. Therefore, the combustion chamber needs sufficient flexibility and containment capacity. Existing combustion chambers often only consider the strength of the combustion chamber itself. When the turbine disc ruptures or malfunctions, high-speed debris often penetrates the combustion chamber, destroys pipes and wiring, damages the aircraft nacelle, and causes fuel and lubricating oil to splash and ignite inside the nacelle. To prevent debris from penetrating the combustion chamber casing, the casing is often locally thickened to 5 to 6 times its original thickness. However, this measure greatly increases the weight of the engine and significantly raises manufacturing costs.
[0032] Furthermore, the high-pressure air comes into direct contact with the combustion chamber casing, heating it through convection and radiation heat transfer. Simultaneously, the high-temperature combustion gases heat the casing through radiation, leading to an increase in its temperature. The numerous pipes and wiring between the combustion chamber casing and the engine compartment are not resistant to high temperatures, necessitating measures to prevent heat transfer from the combustion chamber casing to the outside. Existing combustion chambers often have a thick, heavy insulation layer wrapped around the outside of the casing. This insulation layer is heavy, has poor assembly properties, and is susceptible to damage from impacts or leakage of fuel oil, potentially causing failure.
[0033] The following is combined Figures 1 to 10 The following describes embodiments of the present invention.
[0034] According to an embodiment of the present invention, in one aspect, a combustion chamber is provided, including an outer casing assembly 10, an inner casing assembly 20, a flame tube 50, a fuel nozzle 30, a compressor diffuser 60, and a turbine rotor 70.
[0035] The inner casing assembly 20 is connected to the outer casing assembly 10 at one end. The inner casing assembly 20 has a gas flow channel on its inner side. The inner casing assembly 20 includes, in radial outward direction, an inner casing body 21, a baffle 22, an inner containment layer 26, and an inner containment ring 25. The inner containment layer 26 is flexible, while the baffle 22 and the inner containment ring 25 are made of rigid materials. The flame tube 50 is located between the outer casing assembly 10 and the inner casing assembly 20 and is connected to the gas flow channel. The fuel nozzle 30 is connected to the fuel main pipe 40 and passes through the outer casing assembly 10 and extends into the flame tube 50. The compressor diffuser 60 is located at the end of the outer casing assembly 10 away from the fuel nozzle 30. The blades of the turbine rotor 70 are located in the gas flow channel.
[0036] In this embodiment, when the engine is running, high-pressure air enters the combustion chamber through the passage between the compressor diffuser 60 and the outer casing assembly 10, and then enters the flame tube 50. Fuel enters multiple fuel nozzles 30 from the fuel manifold 40 and is injected into the flame tube 50. Inside the flame tube 50, the high-pressure air and fuel mix and burn, releasing heat to form high-temperature gas (greater than 1300°C). The high-temperature gas flows into the gas flow channel, impacting the blades of the turbine rotor 70 to rotate at high speed and perform work. The high-temperature gas entering the gas flow channel impacts the turbine rotor 70 to rotate at high speed and perform work, with a maximum speed of nearly 80,000 revolutions per minute. Under abnormal conditions, the entire turbine rotor 70 or the rotor disc may break. The inner casing assembly 20, arranged radially outward, includes an inner casing body 21, a baffle 22, an inner containment layer 26, and an inner containment ring 25. The inner containment layer 26 is flexible, while the baffle 22 and the inner containment ring 25 are made of rigid materials. High-speed flying turbine disc fragments will penetrate the inner casing body 21 and the baffle 22 and come into contact with the inner containment layer 26. The inner containment layer 26 has a certain degree of elasticity and tensile strength. When high-speed flying fragments come into contact with the inner containment layer 26, the inner containment layer 26 can effectively reduce the kinetic energy of the fragments, containing small fragments or blades inside the inner containment layer 26 to prevent damage to the flame tube 50. When the high-speed flying fragments are large pieces of turbine discs, the inner containment layer 26 may be damaged. The inner containment ring 25, located outside the inner containment layer 26, can further prevent fragments or turbine discs from flying out and damaging the flame tube 50. The inner containment layer 26 and the inner containment ring 25 work together to effectively prevent fragments from flying out and penetrating the combustion chamber.
[0037] Specifically, the flame tube 50 is provided with an outer ring main combustion hole 51, an outer ring intermediate hole 52, an outer ring mixing hole 53, an inner ring main combustion hole 54, an inner ring intermediate hole 55, and an inner ring mixing hole 56, such as Figure 9The blue line with arrows indicates the direction: high-pressure air enters the combustion chamber through the passage between the compressor diffuser 60 and the outer casing assembly 10. Then, the high-pressure air enters the flame tube 50 through the outer ring main combustion port 51, the outer ring intermediate port 52, the outer ring mixing port 53, the inner ring main combustion port 54, the inner ring intermediate port 55, and the inner ring mixing port 56. Simultaneously, as... Figure 9 The dotted line with arrows indicates the direction. Fuel enters from the fuel main pipe 40 into multiple fuel nozzles 30 and is injected into the flame tube 50. Inside the flame tube 50, high-pressure air entering from the outer ring main combustion port 51 and the inner ring main combustion port 54 mixes with the fuel and combusts, releasing heat to form high-temperature gas (greater than 1300℃). Figure 9 The red line with arrows indicates the direction: the high-temperature gas flows into the gas flow channel. During this flow, it comes into contact with the high-pressure air entering the flame tube 50 through the outer ring central hole 52 and the inner ring central hole 55, further ensuring complete combustion of the fuel and homogenizing the gas temperature. The mixed high-temperature gas continues to flow into the gas flow channel, further mixing with the high-pressure air entering the flame tube 50 through the outer ring mixing hole 53 and the inner ring mixing hole 56, making the circumferential temperature of the high-temperature gas even more uniform. Finally, it enters the gas flow channel, impacting the blades of the turbine rotor 70 to rotate at high speed and perform work.
[0038] Specifically, the compressor diffuser 60 and the outer casing assembly 10 form a sealed space for the combustion chamber.
[0039] In one embodiment, such as Figure 4 As shown, the thickness of the inner ring 25 at the position corresponding to the turbine rotor 70 is greater than the thickness at other positions.
[0040] In this embodiment, the thickness of the inner containment ring 25 at the position corresponding to the turbine rotor 70 is greater than the thickness at other positions. The inner containment ring 25 and the inner containment layer 26 work together to prevent debris from flying out, while avoiding excessive overall thickness of the inner casing assembly 20, which would result in excessive engine weight and save costs.
[0041] Specifically, such as Figure 1 and Figure 4 As shown, Figure 1 The diagram shows two turbine rotors 70. The inner containing ring 25 has a larger thickness at the position corresponding to the turbine rotor 70 and a smaller thickness at the position corresponding to the middle of the two rotors.
[0042] In one embodiment, the inner casing body 21 includes a main body and a first connecting part 213 located at one end of the main body. The first connecting part 213 is connected to the outer casing assembly 10. Multiple bosses 211 are provided at intervals along the circumference at both ends of the main body. The two ends of the baffle 22, the inner containing layer 26 and the inner containing ring 25 are fixed to the bosses 211.
[0043] In this embodiment, multiple bosses 211 are provided at circumferential intervals at both ends of the main body. The two ends of the baffle 22, the inner containing layer 26 and the inner containing ring 25 are fixed to the bosses 211. A cooling space is formed between the baffle 22 and the main body. High-pressure air can enter the cooling space through the gap between two adjacent bosses 211 to cool the turbine rotor 70.
[0044] In one embodiment, such as Figures 5 to 8 As shown, the boss 211 is provided with a body bolt hole 212, the baffle 22 is provided with a baffle through hole 221 corresponding to the body bolt hole 212, the baffle through hole 221 is provided with a U-shaped groove 222 outside, the inner containing layer 26 is formed by the rope wrapped around the baffle 22, the two ends of the rope are embedded in the U-shaped groove 222, the inner containing ring 25 is provided with a bolt through hole 251 corresponding to the baffle through hole 221, and the fastener 24 passes through the bolt through hole 251 and the baffle through hole 221 and is fastened to the body bolt hole 212.
[0045] In this embodiment, the boss 211 is provided with a body bolt hole 212, the baffle 22 is provided with a baffle through hole 221 corresponding to the body bolt hole 212, and a U-shaped groove 222 is provided outside the baffle through hole 221. The inner containing layer 26 is formed by the rope wrapped around the baffle 22, and the two ends of the rope are embedded in the U-shaped groove 222. The inner containing ring 25 is provided with a bolt through hole 251 corresponding to the baffle through hole 221. The fastener 24 passes through the bolt through hole 251 and the baffle through hole 221 and is fastened to the body bolt hole 212. While the fastener 24 fixes the baffle 22 and the inner containing ring 25 to the inner casing body 21, it also causes the inner containing layer 26 to press the baffle 22 and lock the two ends of the rope in the U-shaped groove 222. The inner containment layer 26 is formed by a rope wrapped around the baffle 22. The inner containment layer 26 has a certain degree of elasticity and tensile strength. When high-speed flying debris comes into contact with the inner containment layer 26, the rope of the inner containment layer 26 deforms to wrap the flying debris. At the same time, the single rope has good tensile strength, which can effectively reduce the kinetic energy of the debris and contain small debris or blades inside the inner containment layer 26 to prevent damage to the flame tube 50.
[0046] Specifically, fastener 24 is a bolt.
[0047] In one embodiment, a washer 23 is provided between the bolt and the outer containment ring.
[0048] Specifically, the inner containment layer 26 is formed by tightly spiraling a rope around the outside of the baffle 22. The front end of the rope is wound in the U-shaped groove 222, and after winding around the baffle through hole 221 by 180°, it begins to wind around the baffle 22. After completing the last turn of winding, the rear end of the rope is wound in the U-shaped groove 222 on the other side of the baffle 22, and after winding around the baffle through hole 221 by 180°, it is cut off, thus forming an inner containment layer 26.
[0049] In an alternative embodiment, the U-shaped slot 222 can also be figure-eight shaped, with any number of turns or S-shaped winding around the baffle through hole 221.
[0050] In one specific embodiment, the rope is made of aramid rope braided or wound. The aramid rope is made of aramid multifilament as raw material, which is twisted, braided and post-treated, and has certain elasticity and tensile strength.
[0051] In an alternative embodiment, the inner containment layer 26 may also be formed of fabric.
[0052] In one embodiment, the main body is provided with an inner casing rear cooling hole 214, an inner casing middle cooling hole 215 and an inner casing front cooling hole 216 spaced apart along its axial direction, and the inner casing rear cooling hole 214, inner casing middle cooling hole 215 and inner casing front cooling hole 216 penetrate the main body radially.
[0053] In this embodiment, the main body is provided with an inner casing rear cooling hole 214, an inner casing middle cooling hole 215, and an inner casing front cooling hole 216 spaced along its axial direction. The inner casing rear cooling hole 214, inner casing middle cooling hole 215, and inner casing front cooling hole 216 penetrate the main body radially. High-pressure air can enter the cooling space between the baffle 22 and the main body through the gap between two adjacent bosses 211, and then enter the interior of the gas flow channel through the inner casing rear cooling hole 214, inner casing middle cooling hole 215, and inner casing front cooling hole 216 to cool the turbine rotor 70.
[0054] In one embodiment, the outer casing assembly 10 includes an outer casing body 11, a heat insulation layer 14, an outer casing 12, and a nozzle mounting seat 13. The outer casing body 11 is connected to the end of the inner casing body 21. The nozzle mounting seat 13 passes through the outer casing body 11, the heat insulation layer 14, and the outer casing 12. The nozzle mounting seat 13 is provided with a nozzle mounting hole 131 through which a fuel nozzle 30 passes.
[0055] In this embodiment, since the temperature of high-pressure air is usually greater than 400°C, the high-pressure air is in direct contact with the outer casing body 11 of the outer casing assembly 10, heating the outer casing body 11 in the form of convection heat transfer and radiation heat transfer. The high-temperature gas heats the outer casing body 11 in the form of radiation heat transfer during the flow process. These two forms of heat transfer cause the temperature of the outer casing body 11 to rise significantly. By setting the heat insulation layer 14, the heat insulation layer 14 can block the outer casing body 11 from transferring heat to the outer casing 12, effectively reducing the temperature of the outer casing 12 and preventing the pipes and lines arranged on the outside of the outer casing 12 from aging and failing due to high temperature.
[0056] In one embodiment, the outer casing 11 has a second connecting portion 113, which is fixedly connected to the first connecting portion 213 of the inner casing 21.
[0057] Specifically, the first connecting part 213 is the rear inner casing flange, the second connecting part 113 is the rear flange and the welding ring, and the rear inner casing flange and the rear flange are connected by bolts.
[0058] Specifically, the nozzle mounting base 13 passes sequentially from the inside to the outside through the nozzle hole 112, the heat insulation layer 14, and the outer casing 12 of the outer casing body 11. The nozzle mounting base 13 has a mounting edge 132, which is welded to the inner surface of the outer casing body 11. The outer wall of the nozzle mounting base 13 is welded to the outer casing 12. The flame tube 50 is located inside the outer casing assembly 10. Multiple fuel nozzles 30 pass through the nozzle mounting holes 131 in the nozzle mounting base 13 and extend into the flame tube 50 to fix the flame tube 50. The fuel main pipe 40 is connected to the multiple fuel nozzles 30 to supply fuel (aviation kerosene) to the combustion chamber.
[0059] Specifically, the outer casing 11 includes an inner shell 114, a second connecting portion 113 located at its rear end, and a third connecting portion 111 located at its front end. The third connecting portion 111, the inner shell 114, and the second connecting portion 113 can be integrally machined using forgings, or the third connecting portion 111 and the second connecting portion 113 can be machined using forgings, the inner shell 114 can be stamped using sheet metal, and then the second connecting portion 113, the inner shell 114, and the third connecting portion 111 can be welded together using a welding process.
[0060] Specifically, the third connection part 111 includes a front flange and a slot. The rear end of the outer shell 12 overlaps with and is welded to the second connection part 113. The front end of the outer shell 12 is inserted into the slot of the third connection part 111 and welded to it. The compressor diffuser 60 overlaps with the third connection part 111 to form a sealed space for the combustion chamber.
[0061] In one embodiment, the insulation layer 14 is made of microporous composite cotton.
[0062] In this embodiment, the heat insulation layer 14 is made of microporous composite cotton, which is composed of silicon dioxide, microparticles, metal oxides and short fibers. The stacking of fibers results in a large number of micropores inside, which has a low thermal conductivity and good temperature resistance. Therefore, it can effectively block the heat from the outer casing 11 to the outer shell 12, thereby effectively reducing the temperature of the outer shell 12 and preventing the pipes and lines arranged on the outside of the outer shell 12 from aging and failing at high temperature.
[0063] In one embodiment, the outer casing assembly 10 further includes an outer containment layer 15 disposed between the thermal insulation layer 14 and the outer casing 12, the outer containment layer 15 being flexible.
[0064] In this embodiment, high-temperature gas impacts the turbine rotor 70, causing it to rotate at high speed and perform work. The maximum speed is nearly 80,000 revolutions per minute. Under abnormal circumstances, the entire turbine rotor 70 or the wheel may rupture. High-speed flying debris will penetrate the inner casing 21 and the baffle 22, and come into contact with the inner containment layer 26. The inner containment layer 26 has certain elasticity and tensile strength properties. When the high-speed flying debris comes into contact with the inner containment layer 26, the inner containment layer 26 can effectively reduce the kinetic energy of the debris, containing small debris or blades inside the inner containment layer 26 to prevent damage to the flame tube 50. When the fragments are large pieces of turbine disk, the inner containment layer 26 may be damaged. The inner containment ring 25 located outside the inner containment layer 26 can further prevent the fragments or turbine disk from flying out and damaging the flame tube 50. When the disk passes through the containment ring and breaks the flame tube 50, it reaches the outer casing assembly 10. Since the outer casing assembly 10 includes an outer containment layer 15 located between the heat insulation layer 14 and the outer casing 12, the outer containment layer 15 is flexible. The outer containment layer 15 can wrap the flying disk by deformation, which can effectively reduce the kinetic energy of the disk and wrap it inside the outer containment layer 15 to prevent damage to external pipes and lines.
[0065] In one embodiment, the outer containment layer 15 is formed by a rope wrapped around the outside of the insulation layer 14.
[0066] In this embodiment, the outer containment layer 15 is formed by a rope wrapped around the heat insulation layer 14. When the high-speed flying disc contacts the containment layer, the outer containment layer 15 deforms to wrap the flying disc. At the same time, the single rope has good tensile strength, which can effectively reduce the kinetic energy of the disc and wrap it inside the outer containment layer 15 to prevent damage to external pipes and lines.
[0067] Specifically, the outer enclosing layer 15 is composed of aramid rope braiding or winding. The aramid rope is made of aramid multifilament as raw material, which is twisted, braided and post-treated, and has certain elasticity and tensile strength.
[0068] More specifically, the outer containment layer 15 is formed by a rope tightly wound in a spiral around the outside of the insulation layer 14.
[0069] This embodiment addresses the physical contradiction of the combustion chamber requiring both good rigidity and strength reserves, as well as sufficient flexibility and containment capacity. It employs a spatial separation method, dividing the outer casing assembly 10 into four layers: the outer casing body 11, the outer shell 12, the heat insulation layer 14, and the containment layer. The outer casing body 11 and the outer shell 12 possess good rigidity, the heat insulation layer 14 provides heat insulation, and the containment layer provides sufficient containment capacity. The inner casing assembly 20 is divided into a baffle 22, an inner containment ring 25, and an inner containment layer 26. The baffle 22 and the inner containment layer 26 possess good rigidity, and the inner containment ring 25 provides sufficient containment capacity.
[0070] According to an embodiment of the present invention, in another aspect, an auxiliary power device having a combustion chamber is also provided, including the combustion chamber provided in the above embodiments.
[0071] In this auxiliary power unit, when the engine is running, high-pressure air enters the combustion chamber through the passage between the compressor diffuser 60 and the outer casing assembly 10, and then enters the flame tube 50. Fuel enters from the fuel main 40 through multiple fuel nozzles 30 and is injected into the flame tube 50. Inside the flame tube 50, the high-pressure air and fuel mix and burn, releasing heat to form high-temperature gas (greater than 1300°C). This high-temperature gas flows into the gas flow channel, impacting the blades of the turbine rotor 70, causing it to rotate at high speed and perform work. The high-temperature gas entering the gas flow channel impacts the turbine rotor 70, causing it to rotate at high speed and perform work, with a maximum speed of nearly 80,000 revolutions per minute. Under abnormal conditions, the entire turbine rotor 70 or the rotor disc may break. The inner casing assembly 20, arranged radially outward, includes an inner casing body 21, a baffle 22, an inner containment layer 26, and an inner containment ring 25. The inner containment layer 26 is flexible, while the baffle 22 and the inner containment ring 25 are made of rigid materials. High-speed flying turbine disc fragments will penetrate the inner casing body 21 and the baffle 22 and come into contact with the inner containment layer 26. The inner containment layer 26 has a certain degree of elasticity and tensile strength. When high-speed flying fragments come into contact with the inner containment layer 26, the inner containment layer 26 can effectively reduce the kinetic energy of the fragments, containing small fragments or blades inside the inner containment layer 26 to prevent damage to the flame tube 50. When the high-speed flying fragments are large pieces of turbine discs, the inner containment layer 26 may be damaged. The inner containment ring 25, located outside the inner containment layer 26, can further prevent fragments or turbine discs from flying out and damaging the flame tube 50. The inner containment layer 26 and the inner containment ring 25 work together to effectively prevent fragments from flying out and penetrating the combustion chamber.
[0072] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by this application.
Claims
1. A combustion chamber, characterized in that, include: Outer casing assembly (10); The inner casing assembly (20) is connected to the outer casing assembly (10) at one end. The inner casing assembly (20) has a gas flow channel on its inner side. The inner casing assembly (20) includes an inner casing body (21), a baffle (22), an inner containment layer (26), and an inner containment ring (25) in a radially outward direction. The inner containment layer (26) is flexible, while the baffle (22) and the inner containment ring (25) are made of rigid materials. A flame tube (50) is disposed between the outer casing assembly (10) and the inner casing assembly (20) and is connected to the gas flow channel; A fuel nozzle (30) is connected to a fuel main (40), the fuel nozzle (30) passing through the outer casing assembly (10) and extending into the flame tube (50); A compressor diffuser (60) is located at the end of the outer casing assembly (10) away from the fuel nozzle (30); The turbine rotor (70) has blades located in the gas flow channel.
2. The combustion chamber according to claim 1, characterized in that, The thickness of the inner ring (25) at the position corresponding to the turbine rotor (70) is greater than the thickness at other positions.
3. The combustion chamber according to claim 1, characterized in that, The inner casing body (21) includes a main body and a first connecting part (213) located at one end of the main body. The first connecting part (213) is connected to the outer casing assembly (10). Multiple bosses (211) are provided at circumferential intervals at both ends of the main body. The two ends of the baffle (22), the inner containment layer (26) and the inner containment ring (25) are fixed to the bosses (211).
4. The combustion chamber according to claim 3, characterized in that, The boss (211) is provided with a body bolt hole (212). The baffle (22) is provided with a baffle through hole (221) corresponding to the body bolt hole (212). A U-shaped groove (222) is provided outside the baffle through hole (221). The inner containment layer (26) is formed by a rope wrapped around the baffle (22). The two ends of the rope are embedded in the U-shaped groove (222). The inner containment ring (25) is provided with a bolt through hole (251) corresponding to the baffle through hole (221). The fastener (24) passes through the bolt through hole (251) and the baffle through hole (221) and is fastened to the body bolt hole (212).
5. The combustion chamber according to claim 3, characterized in that, The main body is provided with an inner casing rear cooling hole (214), an inner casing middle cooling hole (215) and an inner casing front cooling hole (216) spaced along its axial direction. The inner casing rear cooling hole (214), inner casing middle cooling hole (215) and inner casing front cooling hole (216) penetrate the main body in the radial direction.
6. The combustion chamber according to any one of claims 1 to 5, characterized in that, The outer casing assembly (10) includes an outer casing body (11), a heat insulation layer (14), an outer casing (12), and a nozzle mounting seat (13). The outer casing body (11) is connected to the end of the inner casing body (21). The nozzle mounting seat (13) passes through the outer casing body (11), the heat insulation layer (14), and the outer casing (12). The nozzle mounting seat (13) is provided with a nozzle mounting hole (131), and the fuel nozzle (30) passes through the nozzle mounting hole (131).
7. The combustion chamber according to claim 6, characterized in that, The insulation layer (14) is made of microporous composite cotton.
8. The combustion chamber according to claim 6, characterized in that, The outer casing assembly (10) also includes an outer enclosure layer (15) disposed between the heat insulation layer (14) and the outer casing (12), the outer enclosure layer (15) being flexible.
9. The combustion chamber according to claim 8, characterized in that, The outer containment layer (15) is formed by a rope wrapped around the outside of the insulation layer (14).
10. An auxiliary power unit having a combustion chamber, characterized in that, include: The combustion chamber according to any one of claims 1 to 9.