Muffler for an aeronautical internal combustion engine and aeronautical internal combustion engine
By employing a multi-layered pleated baffle design and metal 3D printing technology in the internal combustion engine muffler, the problem of large size and heavy weight of the exhaust muffler has been solved, thus meeting the noise reduction requirements of low-altitude aircraft.
Patent Information
- Application Number
- CN202610677962.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-05-15
- Publication Date
- 2026-07-24
AI Technical Summary
Existing internal combustion engine exhaust mufflers are too large and heavy to meet the needs of low-altitude aircraft.
The design employs a multi-layered pleated partition, which scatters, reflects, refracts, and diffracts sound waves, causing them to collide and cancel each other out, thus reducing sound energy and intensity. When the sound energy is concentrated, the sound waves are broken and scattered by the pleats as they pass through the multi-layered pleated partition, gradually attenuating. Furthermore, it is manufactured using metal 3D printing to achieve a small size and light weight.
It achieves a significant noise reduction effect while reducing the size and weight of the silencer, making it suitable for the needs of low-altitude aircraft.
Smart Images
Figure CN122447170A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to internal combustion engines, and specifically provides a muffler for an aircraft internal combustion engine and an aircraft internal combustion engine. Background Technology
[0002] An aircraft is a flying machine that flies within the atmosphere and obtains lift by relying on air buoyancy or aerodynamics.
[0003] Aircraft are classified into low-altitude aircraft and high-altitude aircraft according to their flight altitude. Low-altitude aircraft generally fly at altitudes below 2,000 meters, while high-altitude aircraft typically fly at altitudes above 6,000 meters.
[0004] Low-altitude aircraft differ from high-altitude aircraft in that they require noise level restrictions. However, current internal combustion engine exhaust mufflers are too large and heavy to meet the needs of low-altitude aircraft. Therefore, there is an urgent need to develop a muffler that is small in size, lightweight, and has a significant noise reduction effect. Summary of the Invention
[0005] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem that the exhaust mufflers of existing internal combustion engines are too large and heavy, making them unsuitable for the needs of low-altitude aircraft.
[0006] In a first aspect, the present invention provides a muffler for an aircraft internal combustion engine, the muffler comprising: An air inlet and an air outlet, with an airflow channel formed between the air inlet and the air outlet; and Multi-layered pleated partitions are spaced out within the airflow channel; Each layer of pleated baffle is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layered pleated baffle is configured to continuously reflect and refract the sound waves in multiple stages, so that the sound waves collide with each other to cancel out the sound energy and reduce the sound intensity. When the sound energy of the concentrated sound waves passes through the multi-layered pleated baffle, they are broken and scattered by the pleats and attenuated step by step.
[0007] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the multi-layer pleated baffle is further configured such that the diffracted sound waves are reflected at right angles along the original direction after hitting the next layer of pleated baffle, thus preventing the sound intensity from spreading to the next level.
[0008] In the preferred embodiment of the above-mentioned muffler for an aircraft internal combustion engine, the airflow channel is provided with a first to a third layer of pleated baffles along the airflow direction. The pleat size of each layer of pleated baffles is different to accommodate sound waves of different wavelengths. Each layer of pleated baffles includes continuous pleated segments and spaced pleated segments. The continuous pleated segments are configured to scatter, reflect, and refract the sound waves, and the spaced pleated segments diffract and refract the sound waves. The spaced pleated segments in the upper layer of the first to third layers of pleated baffles correspond to the continuous pleated segments in the lower layer.
[0009] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the first layer of spaced pleated segments is constructed as a two-in-one acoustic diffraction strip-shaped slit channel.
[0010] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the included angle of each fold in the first layer of pleated partition is 60°.
[0011] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the second layer of spaced pleated segments is constructed as a two-in-one acoustic diffraction strip-shaped slit channel.
[0012] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the included angle of each fold in the second layer of pleated partition is 60°.
[0013] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the third layer of spaced pleated segments is constructed as a two-part acoustic diffraction strip-shaped slit channel.
[0014] In the preferred technical solution of the above-mentioned muffler for aircraft internal combustion engines, the included angle of each fold in the third layer of pleated partition is 60°.
[0015] In a second aspect, the present invention also provides an aviation internal combustion engine, the aviation internal combustion engine including the above-described muffler for an aviation internal combustion engine.
[0016] With the above technical solution, the muffler for an aircraft internal combustion engine and the aircraft internal combustion engine of the present invention are described. The muffler includes an air inlet, an air outlet, and multi-layer pleated baffles. An airflow channel is formed between the air inlet and the air outlet. The multi-layer pleated baffles are arranged in a spaced manner within the airflow channel. Each layer of pleated baffles is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layer pleated baffles are configured to continuously reflect and refract the sound waves in multiple stages, so that the sound waves collide with each other to cancel out the sound energy and reduce the sound intensity. When the sound waves with concentrated sound energy pass through the multi-layer pleated baffles, they are broken and scattered by the pleats and gradually attenuated. Therefore, the muffler of the present invention has a significant noise reduction effect. The muffler of the present invention is manufactured by metal 3D printing, so it can achieve the effect of small size and light weight. Attached Figure Description
[0017] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which: Figure 1 This is a schematic rendering of a muffler for an aircraft internal combustion engine according to an embodiment of the present invention; Figure 2 yes Figure 1 A schematic outline view of a muffler used in aircraft internal combustion engines from another angle; Figure 3 yes Figure 2 A schematic wireframe diagram of a muffler used in aircraft internal combustion engines; Figure 4 yes Figure 1 A schematic cross-sectional view of a muffler used in aircraft internal combustion engines; Figure 5 yes Figure 4 A schematic airflow diagram of a muffler used in aircraft internal combustion engines; Figure 6 yes Figure 4 A schematic diagram of the noise reduction operation of a muffler used in aircraft internal combustion engines.
[0018] The symbols in the diagram represent the following meanings: 100 Mufflers for aircraft internal combustion engines 10 air intakes, 20 air outlets 30+ layers of pleated partitions; 31 First layer of pleated partition; 311 First layer of continuous pleated segments; 312 First layer of spaced-out pleated segments; 32 Second layer of pleated partition; 321 Second layer of continuous pleated segments; 322 Second layer of spaced-out pleated segments; 33 Third layer of pleated partition; 331 Third layer of continuous pleated segments; 332 Third layer of spaced-out pleated segments; 34 Two-in-one acoustic diffraction strip-shaped slit channel; 35 One-in-two acoustic diffraction strip-shaped slit channel. A represents the airflow path. Detailed Implementation
[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.
[0020] It should be noted that in the description of this invention, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," indicating directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0021] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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 direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0022] Figure 1 This is a schematic rendering of a muffler for an aircraft internal combustion engine according to an embodiment of the present invention. Figure 1 The external shape and partial internal structure of the muffler are shown. Figure 2 yes Figure 1 A schematic outline of a muffler used in aircraft internal combustion engines from another angle. Figure 2 The shape of the muffler is shown. Figure 3 yes Figure 2 A schematic wireframe diagram of a muffler used in aircraft internal combustion engines. Figure 3 The external shape of the muffler and its internal multi-layered pleated baffles are shown. Figure 4 yes Figure 1 A schematic cross-sectional view of a muffler used in aircraft internal combustion engines. Figure 4 The specific structure of the multi-layered pleated baffle inside the muffler is shown. Figure 5 yes Figure 4 A schematic airflow diagram of a muffler used in aircraft internal combustion engines. Figure 5 The diagram shows the airflow path A, which is the process of airflow flowing from the inlet through the multi-layered pleated baffle and out of the outlet. Figure 6 yes Figure 4 A schematic diagram illustrating the noise reduction operation of a muffler used in aircraft internal combustion engines. Figure 6 The noise reduction conditions involving scattering, reflection, refraction, and diffraction are shown.
[0023] like Figure 1 As shown, see also Figures 2-6 To address the problem that existing internal combustion engine exhaust mufflers are too large and heavy to meet the needs of low-altitude aircraft, this invention provides a muffler 100 for aircraft internal combustion engines, such as... Figure 3As shown, the silencer 100 includes an air inlet 10, an air outlet 20, and multi-layered pleated baffles 30. An airflow channel is formed between the air inlet 10 and the air outlet 20. The multi-layered pleated baffles 30 are spaced apart within the airflow channel. Each pleated baffle is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layered pleated baffles 30 are configured to continuously reflect and refract the sound waves in multiple stages, causing the sound waves to collide and cancel each other out, reducing the sound intensity. When the sound waves with concentrated sound energy pass through the multi-layered pleated baffles 30, they are broken and scattered by the pleats, and attenuated step by step.
[0024] like Figure 3 As shown, the muffler 100 for an aircraft internal combustion engine of the present invention includes an air inlet 10, an air outlet 20, and a multi-layer pleated baffle 30. Each layer of the pleated baffle is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layer pleated baffle 30 is configured to continuously reflect and refract the sound waves in multiple stages, so that the sound waves collide with each other to cancel out the sound energy and reduce the sound intensity. When the sound waves with concentrated sound energy pass through the multi-layer pleated baffle 30, they are broken and scattered by the pleats and attenuated step by step. Therefore, the muffler 100 of the present invention has a significant noise reduction effect. The muffler 100 of the present invention is manufactured by metal 3D printing, so it can achieve the effect of small size and light weight.
[0025] As one possible implementation method, such as Figure 6 As shown, the multi-layer pleated partition 30 is also configured such that the diffracted sound waves will be reflected at right angles along the original direction after hitting the next layer of pleated partition, thus preventing the sound intensity from spreading to the next level and further increasing the sound absorption effect.
[0026] As one possible implementation method, see Figure 3 The number of multi-layer pleated partitions 30 can be two layers, three layers, or four layers, etc., depending on the noise reduction effect of the silencer 100.
[0027] As one possible implementation method, such as Figure 3 As shown, see also Figure 4 The spacing of the multi-layered pleated partition 30 can be different, and the size of the pleats in each layer of the pleated partition is different, so as to cancel out sound waves of different wavelengths.
[0028] As one possible implementation method, such as Figure 3 As shown, see also Figure 4 and Figure 6 Each layer of the multi-layered pleated partition 30 includes continuous pleated segments and spaced pleated segments. The continuous pleated segments are configured to scatter, reflect, and refract sound waves, while the spaced pleated segments diffract and refract sound waves.
[0029] As one possible implementation method, such as Figure 4As shown, see also Figure 6 The multi-layered pleated partition 30 consists of three layers: a first layer of pleated partition 31, a second layer of pleated partition 32, and a third layer of pleated partition 33, arranged along the airflow direction within the airflow channel. The size of the pleats in each of the three layers varies to accommodate sound waves of different wavelengths. Each layer of pleated partition includes continuous pleated segments and spaced pleated segments. The first layer of pleated partition 31 includes a first layer of continuous pleated segments 311 and a first layer of spaced pleated segments 312. The second layer of pleated partition 32 includes a second layer of continuous pleated segments 321 and a second layer of spaced pleated segments 322. The third layer of pleated partition 33 includes a third layer of continuous pleated segments 331 and a third layer of spaced pleated segments 332. Each layer of continuous pleated segments, namely the first layer of spaced pleated segments 312, the second layer of spaced pleated segments 322, and the third layer of spaced pleated segments 332, is configured to scatter, reflect, and refract sound waves. Each layer of spaced pleated segments, namely the first layer of spaced pleated segments 312, the second layer of spaced pleated segments 322, and the third layer of spaced pleated segments 332, diffracts and refracts sound waves. In the first layer of pleated partitions 31, 32, and 33, the upper spaced pleated segments correspond to the lower continuous pleated segments; the first layer of spaced pleated segments 312 corresponds to the second layer of continuous pleated segments; and the second layer of spaced pleated segments 322 corresponds to the third layer of continuous pleated segments. Further, as... Figure 6 As shown, the first layer of spaced pleated segments 312 causes the diffracted sound waves to be reflected at right angles along the original direction after hitting the second layer of continuous pleated segments, thus preventing the sound intensity from spreading to the next level. The second layer of spaced pleated segments 322 causes the diffracted sound waves to be reflected at right angles along the original direction after hitting the third layer of continuous pleated segments, thus preventing the sound intensity from spreading to the next level, thereby further increasing the noise reduction effect.
[0030] As one possible implementation method, such as Figure 4 As shown, see also Figure 6 The first layer of interspersed folded segments 312 forms a two-in-one acoustic diffraction strip-shaped slit channel 34, that is, two upper channels share one lower channel.
[0031] As one possible implementation method, such as Figure 6 As shown, see also Figure 4 In the first layer of pleated partition 31, the included angle of each pleat is 60°.
[0032] As one possible implementation method, such as Figure 4 As shown, see also Figure 6 The second layer of interspersed folded segments 322 forms a two-in-one acoustic diffraction strip-shaped slit channel 34, that is, two upper channels share one lower channel.
[0033] As one possible implementation method, such as Figure 4 As shown, see also Figure 6 In the second layer of pleated partition 32, the included angle of each pleat is 60°.
[0034] As one possible implementation method, such as Figure 4 As shown, see also Figure 6 The third layer of folded segments 332 forms a two-part acoustic diffraction strip channel, that is, an upper channel is split into two lower channels.
[0035] As one possible implementation method, such as Figure 4 As shown, see also Figure 6 In the third layer of pleated partition 33, the included angle of each pleat is 60°.
[0036] like Figure 5 As shown, see also Figure 6 The airflow enters through the scattering inlet 10, and after passing through the first layer of continuous pleated sections 311, the sound waves of the airflow are reflected and refracted. Then, after passing through the first layer of spaced pleated sections 312, the sound waves are diffracted and refracted again. Next, after passing through the second layer of continuous pleated sections 321, the sound waves are reflected again. Then, after passing through the second layer of spaced pleated sections 322, the sound waves are diffracted and refracted again. Finally, after passing through the third layer of continuous pleated sections 331, the sound waves are reflected again. Then, after passing through the third layer of spaced pleated sections 332, the sound waves are diffracted again. The airflow, after being silenced by the muffler 100, is discharged through the outlet 20. Therefore, when the muffler 100 of this invention is used in low-altitude aircraft internal combustion engines, it continuously reflects and refracts the specific exhaust audio frequencies of the low-altitude aircraft internal combustion engines in multiple stages, causing the sound waves to collide and cancel each other out, reducing the sound intensity. Furthermore, most of the refracted sound energy is repeatedly and continuously reflected and collided by these pleats, compressed at the bottom of the pleats, absorbed, and converted into heat energy, which is carried away by the exhaust gas. Furthermore, the silencer 100 of the present invention causes the concentrated sound waves to be broken and scattered by the pleats when passing through the pleated partition of the silencer 100, thus attenuating them step by step. Further, the diffracted sound waves, after hitting the next layer of pleated partition, are reflected at right angles along the original direction to prevent the sound intensity from spreading to the next level.
[0037] See Figures 1-6 The present invention also provides an aircraft internal combustion engine, which includes the above-described muffler 100 for an aircraft internal combustion engine. Therefore, the structural details of the muffler 100 for an aircraft internal combustion engine will not be described again in this embodiment.
[0038] The present invention relates to an aircraft internal combustion engine, which includes a muffler 100 for the aircraft internal combustion engine. The muffler 100 includes an air inlet 10, an air outlet 20, and a multi-layered pleated baffle 30. An airflow channel is formed between the air inlet 10 and the air outlet 20. The multi-layered pleated baffle 30 is arranged in a spaced manner within the airflow channel. Each layer of the pleated baffle is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layered pleated baffle 30 is configured to continuously reflect and refract the sound waves in multiple stages, and to cause the sound waves to collide with each other to cancel out the sound energy and reduce the sound intensity. As a result, the sound waves with concentrated sound energy are broken and scattered by the pleats when passing through the multi-layered pleated baffle 30, and are gradually attenuated. Therefore, the muffler 100 of the present invention has a significant noise reduction effect. The muffler 100 of the present invention is manufactured by metal 3D printing, thus achieving the effect of small size and light weight.
[0039] The technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.
Claims
1. A muffler for an aircraft internal combustion engine, characterized in that... The muffler includes: An air inlet and an air outlet, with an airflow channel formed between the air inlet and the air outlet; and Multi-layered pleated partitions are spaced out within the airflow channel; Each layer of pleated baffle is configured to scatter, reflect, refract, and diffract the sound waves of the airflow. The multi-layered pleated baffle is configured to continuously reflect and refract the sound waves in multiple stages, so that the sound waves collide with each other to cancel out the sound energy and reduce the sound intensity. When the sound energy of the concentrated sound waves passes through the multi-layered pleated baffle, they are broken and scattered by the pleats and attenuated step by step.
2. The muffler for an aircraft internal combustion engine according to claim 1, characterized in that... The multi-layered pleated partition is also configured such that when the diffracted sound waves hit the next layer of pleated partition, they are reflected at right angles along the original direction, preventing the sound intensity from spreading to the next level.
3. The muffler for an aircraft internal combustion engine according to claim 1 or 2, characterized in that... The airflow channel is provided with a first to a third layer of pleated baffles along the airflow direction. The size of the pleats in each layer of pleated baffles is different to accommodate sound waves of different wavelengths. Each layer of pleated baffles includes continuous pleated segments and spaced pleated segments. The continuous pleated segments are configured to scatter, reflect, and refract the sound waves, while the spaced pleated segments diffract and refract the sound waves. The spaced pleated segments in the upper layer of the first to third layers of pleated baffles correspond to the continuous pleated segments in the lower layer.
4. The muffler for an aircraft internal combustion engine according to claim 3, characterized in that... The first layer of spaced-out folded segments forms a two-in-one acoustic diffraction strip-shaped slit channel.
5. The muffler for an aircraft internal combustion engine according to claim 4, characterized in that... In the first layer of pleated partition, the included angle of each pleat is 60°.
6. The muffler for an aircraft internal combustion engine according to claim 3, characterized in that... The second layer of spaced-out folded segments forms a two-in-one acoustic diffraction strip-shaped slit channel.
7. The muffler for an aircraft internal combustion engine according to claim 6, characterized in that... In the second layer of pleated partition, the included angle of each pleat is 60°.
8. The muffler for an aircraft internal combustion engine according to claim 3, characterized in that... The third layer of spaced-out folded segments forms a two-part acoustic diffraction strip-shaped slit channel.
9. The muffler for an aircraft internal combustion engine according to claim 8, characterized in that... The included angle of each fold in the third layer of pleated partition is 60°.
10. An aircraft internal combustion engine, characterized in that... The aircraft internal combustion engine includes the muffler for an aircraft internal combustion engine as described in any one of claims 1-9.