Acoustic component and air duct equipped with acoustic component

Abstract

The present invention relates to an acoustic component (100) comprising a flow path (16) for a fluid, in particular air, in which at least one flow path section (40) having a silencer volume (20, 24) is arranged between an inlet pipe (10) and an outlet pipe (12) of the flow path (16), the silencer volume (20, 24) in the flow path section (40) is connected to the flow path (16) via an opening (22), and the flow path section (40, 44) having at least the silencer volume (20, 24) is provided with at least one flow deflection device (50) for deflecting the flow of fluid in the flow path section (40, 44) having the silencer volume (20, 24) at least away from the opening (22), the opening (22) of the flow path section (40, 44) being arranged in a protected area of ​​the flow deflection device (50). The present invention further relates to an air duct (200) comprising an acoustic component (100).

Description

[Technical field]

[0001] The present invention relates to an acoustic component and an air duct equipped with an acoustic component, in particular for an internal combustion engine. [Background technology]

[0002] It is known to provide flow passages, such as air ducts, in particular air intake ducts of internal combustion engines, with acoustic measures for noise reduction, for example silencer volumes of the type wideband silencers with resonance chambers are often used.

[0003] Such a wideband silencer is known, for example, from DE 202014007986 C1.

[0004] Especially in vehicles, where installation space is limited, components are made as small as possible. The smaller the tube diameter of broadband silencers, the higher the flow rate with a decreasing tube diameter, which creates new requirements for acoustic countermeasures. Summary of the Invention

[0005] The present invention aims to improve acoustic components for high flow applications.

[0006] A further object is to provide an air duct with acoustic components for high flow rates.

[0007] The above mentioned object is solved according to one aspect of the present invention by an acoustic component comprising a flow path for a fluid, in particular air, in which at least one flow path section having a silencer volume is arranged between an inlet pipe and an outlet pipe of the flow path, in which the silencer volume communicates with the flow path via an opening, in which the flow path section having at least the silencer volume is provided with at least one flow deflection device which deflects the flow of the fluid in the flow path section having the silencer volume at least away from the opening, the opening of the flow path section being arranged in a protected area of ​​the flow deflection device.

[0008] The flow deflector has the effect of deflecting or separating the fluid flow from the walls of the channel. This separation of the flow places the opening of the channel section outside of the core flow and no longer receives it. The opening is located in the wake region of the flow, also known as the dead zone. Thus, in the channel section, the opening is located within the protected area of ​​the flow deflector.

[0009] A further object is solved by an air duct for an internal combustion engine, comprising an acoustic component according to the invention, wherein the acoustic component is arranged on the clean air side of the air inlet, or wherein the acoustic component is arranged on the untreated air side of the air inlet.

[0010] Preferred configurations and advantages of the invention can be obtained from the accompanying claims, the specification and the drawings.

[0011] The proposed acoustic component comprises a flow path for a fluid, in particular air, in which at least one flow path section with a silencer volume is arranged between an inlet pipe and an outlet pipe of the flow path, in which the silencer volume communicates with the flow path via an opening, and in which at least the flow path section with the silencer volume is provided with at least one flow deflection device which deflects the flow of fluid in the flow path section with the silencer volume at least away from the opening, the opening of the flow path section being arranged in a protected area of ​​the flow deflection device.

[0012] Advantageously, whistling noises that may occur at high flow rates can be avoided. For example, acoustic components in clean air ducts, especially broadband silencers, can generate whistling noises in certain operating conditions. This occurs due to the interaction of the silencer volume with the core flow via one or more resonant chambers arranged around the flow path, i.e. openings that connect the silencer volume with the flow path.

[0013] A whistling noise is understood as a tonal noise. It is a narrow-band event in the frequency spectrum, usually between 10 dB and 20 dBb, that stands out from a broadband background noise. The frequency range in which background noise is perceived as whistling or howling spans the entire audible range, i.e., the frequency range from about 500 to 16,000 Hz. Due to its narrow-band nature, this noise is highly noticeable to the human ear and is therefore perceived as harsh.

[0014] The present invention is not limited to broadband silencers, but may also be used in conjunction with other resonators, for example Helmholtz resonators and pipe resonators.

[0015] For example, complex measures to avoid noise can be avoided, such as reducing the cross section of the openings, which would change the actual acoustic performance of the component, covering the openings with a fine mesh grid, which would incur additional costs, or increasing the overall cross section of the pipe to reduce the flow rate, which would take up installation space that would not normally be available.

[0016] Because the flow is directed or separated at least partially away from the openings in the flow path wall before re-contacting the flow path wall at a location axially away from the flow deflection device, noises such as whistling can be effectively reduced without changing the acoustic characteristics of a typical acoustic component.

[0017] The opening may be arranged behind the flow deflector, for example behind a step, or adjacent to the flow deflector, for example adjacent to a longitudinal stay. Different flow deflector devices, for example a step and / or one or more longitudinal stays, may also be combined. Also, a flow passage section with a silencer volume may have multiple longitudinal stays.

[0018] For example, it may be advantageous to prevent noise if the flow passage diameter (if cylindrical) or cross section (particularly if non-cylindrical) is at least partially enlarged at the flow passage portion of the opening, thereby allowing the flow to separate from the opening, effectively preventing whistling noises etc.

[0019] For example, the opening of the broadband silencer is located behind the step. and / Alternatively, it may be disposed between the longitudinal stays.

[0020] No additional components are required, which means no additional costs. The flow deflector can be easily integrated into the injection molding process for manufacturing the acoustic component. The acoustic effect of the acoustic component, especially the damping effect, is not affected. In addition, the cross section does not need to be narrowed, which avoids pressure losses due to narrowing of the cross section. The flow deflector is effective for various shapes of openings.

[0021] The openings can be arbitrarily designed as round holes, slots, parallel to the longitudinal axis, perpendicular to the longitudinal axis, angled to the longitudinal axis, or a combination of openings of different configurations.

[0022] It is possible to provide a robust and easy to manufacture solution for reducing noise, particularly whistling, in broadband silencers without compromising the acoustic attenuation and without inducing an increase in pressure loss.

[0023] According to an advantageous configuration of the acoustic component, the at least one flow deflection device can be provided at least at the transition of the inlet pipe to the flow path section with the silencer volume, which allows a compact configuration of the acoustic component.

[0024] According to an advantageous configuration of the acoustic components, the flow deflector may be configured to have substantially no effect on attenuation: the expansion in diameter or cross section does not act as an acoustic expansion chamber, rather the flow deflector alone does not substantially produce the attenuation effect of an expansion chamber.

[0025] According to an advantageous embodiment of the acoustic component, the outlet pipe may have an equivalent or larger diameter and / or an equivalent or larger cross section than the flow path section with the silencer volume. If the flow path section with the silencer volume is designed conically with an increasing diameter or cross section in the flow direction, at least at the transition of the flow path section with the silencer volume to the outlet pipe, an outlet pipe of equivalent or larger diameter and / or cross section is provided.

[0026] Additionally or alternatively, according to an advantageous embodiment of the acoustic component, the flow passage in the flow passage section with the silencer volume may have a larger diameter and / or cross section than in the inlet pipe.

[0027] In either case, the flow passage in the outlet pipe is at least as large as the flow passage portion having the silencer volume, as opposed to a conventional expansion chamber in which the cross section of the flow passage at the outlet side of the expansion chamber is tapered.

[0028] According to an advantageous embodiment of the acoustic component, the flow deflection device may comprise at least one step, which is designed to be significantly smaller than a conventional expansion chamber. In particular, the step can be configured to have a substantially sharp edge, which facilitates separation of the flow in the flow passage from the wall on which the opening of the silencer volume is provided.

[0029] According to an advantageous embodiment of the acoustic component, the step may be configured to extend in the circumferential direction around the flow path. If necessary, the step may also be provided intermittently in the circumferential direction to form step segments. They may be distributed evenly on the circumference. According to an advantageous embodiment of the acoustic component, the flow deflection device may comprise at least one longitudinal stay protruding into the flow path and extending along the flow path section having the silencer volume in the axial direction along the longitudinal axis. In particular, the at least one longitudinal stay may extend axially at least over the axial extent of the opening. A longitudinal stay introduced inside the tube between the longitudinal openings may enhance the flow "separation" effect.

[0030] If necessary, one or more longitudinal stays can be provided without a step at the inlet of the flow passage section with the silencer volume. The flow is then separated from the opening by the longitudinal stay or stays. The longitudinal stays can be designed to be narrow or wide. If only longitudinal stays are provided without a step, the diameter of the flow passage and thus the diameter of the inlet and outlet pipes can be constant over the extended length, i.e. over the flow passage section with the silencer volume. This is advantageous in that the inner diameter of the pipes and therefore the acoustically effective silencer volume do not have to be reduced. In other words, the longitudinal stays are only arranged at the existing inner radius of the flow passage section with the silencer volume.

[0031] According to an advantageous embodiment of the acoustic component, in the flow path section, a number of longitudinal stays may be arranged around the longitudinal axis.

[0032] Advantageously, regardless of the presence or absence of a step at the inlet of the flow passage section with the silencer volume, longitudinal stays may be arranged between the openings and project into the flow passage like fins. Advantageously, the longitudinal stays extend in the circumferential direction over at least 10° or over at least the same angular range as the openings or rows of openings arranged adjacent in the longitudinal direction of the flow passage section with the silencer volume. This provides a mechanical stability to the flow passage section with the silencer volume, which has an advantageous effect on the manufacture of the acoustic component.

[0033] According to an advantageous embodiment of the acoustic component, two or more flow deflection devices with flow passage sections with silencer volumes may be arranged in succession along the longitudinal axis, which allows the structure to be advantageously adapted for attenuation in a particular frequency range. If several flow passage sections with silencer volumes are arranged in succession, only some of the flow passage sections may be provided with flow deflection devices, if necessary.

[0034] According to a further aspect of the invention there is provided an air duct for an internal combustion engine comprising an acoustic component of the invention, the acoustic component being arranged on the clean air side of the air inlet, or the acoustic component being arranged on the untreated air side of the air inlet.

[0035] Advantageously, annoying noises such as whistling at high flow rates can be reliably prevented. [Brief description of the drawings]

[0036] Further advantages are obtained from the following description of the drawings, in which embodiments of the invention are shown. The drawings, the description and the claims contain a number of features in combination, which the person skilled in the art can consider and combine as appropriate and individually to provide further combinations.

[0037] [Figure 1] 1 is a longitudinal cross-sectional view along an axial direction of an acoustic component according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a plan view of the cross section II-II of the acoustic component of FIG. 1. [Diagram 3] 4 is a longitudinal sectional view along an axial direction of an acoustic component according to a further embodiment of the present invention; FIG. [Figure 4] FIG. 4 is a plan view of the acoustic component of FIG. 3 taken along section IV-IV. [Diagram 5] 1 is a cross-sectional plan view of an acoustic component according to a further embodiment of the present invention; [Figure 6] 1 is a cross-sectional plan view of an acoustic component according to a further embodiment of the present invention; [Figure 7] 4 is a longitudinal sectional view along an axial direction of an acoustic component according to a further embodiment of the present invention; FIG. [Figure 7A] FIG. 2 is a detailed view of a longitudinal section of the acoustic component of FIG. 1, showing the flow passages. [Figure 8] FIG. 2 is a schematic diagram of an air supply duct with an acoustic component according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] In the figures, identical or similar components are designated with the same reference symbols.

[0039] Figures 1 and 2 show an acoustic component 100, in particular a silencer, according to an embodiment of the present invention. Figure 1 shows a longitudinal section along the axial longitudinal axis 60 of the acoustic component 100. Figure 2 shows a plan view of section II-II of the acoustic component 100 of Figure 1.

[0040] The acoustic component 100 comprises a flow passage 16 for a fluid, in particular air, surrounded for example by a cylindrical wall.

[0041] A flow path section 40 having a silencer volume 20 is disposed between the inlet pipe 10 and the outlet pipe 12 of the flow path 16, and in the flow path section 40, the silencer volume 20 communicates with the flow path 16 via an opening 22. The silencer volume 20 is closed on the outside by a cover 26.

[0042] The openings 22 are only partially identified by reference numerals for reasons of clarity. The flow passage 16 extends through the inlet pipe 10, a flow passage section 40 having the silencer volume 20, and the outlet pipe 12.

[0043] At the transition 30 of the inlet pipe 10 to the flow path section 40 having the silencer volume 20, a flow deflection device 50 in the form of a step 52 is provided so that the diameter of the flow path 16 of the flow path section 40 having the silencer volume 20 is enlarged.

[0044] The opening 22 is arranged in the flow passage 40 within the protected area of ​​a flow deflector 50 configured as a step 52. The step 52 is arranged to extend circumferentially around the flow passage 16. The flow deflector 50 is configured to be neutral with respect to the intended damping behavior of the acoustic component, i.e. to have substantially no effect on damping.

[0045] The flow deflector 50 locally deflects the flow in the flow passage section 40 with the silencer volume 20 at the transition section 30 from the opening 22 towards the centre of the flow passage 16 in such a way that the flow of fluid in the flow passage section 40 with the silencer volume 20 separates from the opening 22 and reaches the wall of the flow passage 16 only at some axial distance from the step 52, where the opening 22 is no longer present. For this purpose, it is particularly advantageous for the step 52 to be configured with a sharp edge.

[0046] In this embodiment, the flow deflector 50 faces outward. Thus, the opening 22 is aligned along the longitudinal axis relative to the wall of the inlet pipe 10. 60 The distance to is large.

[0047] However, the flow deflectors 50 may also be provided inwardly, for example in the form of circumferentially extending or intermittent stays.

[0048] The increase in step height or diameter may be practically tailored to the boundary conditions of the flow through the acoustic component 100 .

[0049] The outflow pipe 12 has the same diameter as the flow passage section 40 with the silencer volume 20. If necessary, the outflow pipe 12 may have a larger diameter than the flow passage section 40 with the silencer volume 20. In principle, however, the diameter of the outflow outlet may be smaller than the step section. In this case, the part may be composed of two assemblies. However, the effectiveness of the measure is maintained.

[0050] Figures 3 and 4 show an acoustic component 100 according to a further embodiment of the invention. Figure 3 is a longitudinal section along the axial longitudinal axis 60 of the acoustic component 100. Figure 4 is a plan view of section IV-IV of the acoustic component 100 of Figure 3. The configuration of the acoustic component 100 substantially corresponds to that of Figures 1 and 2, and reference is made to the description thereof to avoid unnecessary repetition.

[0051] In addition to the steps 52 described above in connection with FIGS. 1 and 2 as flow deflector 50 , flow deflector 50 includes two diametrically opposed longitudinal stays 56 that protrude into flow passage 16 .

[0052] The longitudinal stay 56 extends axially along the flow passage section 40 to the outflow pipe 12 and axially covers the axial range of the opening 22 of the flow passage section 40 having the silencer volume 20. The longitudinal stay 56 promotes separation of the flow from the opening 22 of the flow passage section 40 having the silencer volume 20.

[0053] 5 and 6 show a variation of an acoustic component 100 having a longitudinal stay 56. In FIG.

[0054] 5 shows a plan view of a cross section of an acoustic component 100 having four longitudinal stays 56 and stepped portions 52 spaced equidistantly around the longitudinal axis 60 of the flow passage portion 40. The longitudinal stays 56 are interposed between the stepped portions 52.

[0055] A further embodiment of the acoustic component 100 corresponds to the embodiment of figures 1 to 4. The flow passage 16 has a larger cross section in the flow passage part 40 than in the inlet pipe 10.

[0056] Figure 6 shows a plan view of a cross section of an acoustic component 100 in which four longitudinal stays 56 are provided as flow deflection devices 50, but without the step 52. A further embodiment of the acoustic component 100 corresponds to the configuration of figures 1 to 4. The flow passage 16 has a smaller cross section in the flow passage section 40 than in the inlet pipe 10. The longitudinal stays 56 are essentially arranged on the inner radius of the flow passage 16. The inlet pipe 10 and the outlet pipe 12 may have the same inner diameter.

[0057] FIG. 7 is an axial longitudinal section of an acoustic component 100 according to a further embodiment of the present invention.

[0058] The acoustic component 100 comprises a flow passage 16 for a fluid, in particular air, surrounded for example by a cylindrical wall.

[0059] Between the inlet pipe 10 and the outlet pipe 12 of the flow passage 16 is arranged a first flow passage part 40 with a silencer volume 20 communicating with the flow passage 16 via an opening 22, on which is arranged a second flow passage part 44 (only partially shown) with a silencer volume 24 also communicating with the flow passage 16 via an opening 22. The opening 22 is only partially identified by a reference number for reasons of clarity. The flow passage 16 extends through the inlet pipe 10, the flow passage part 40 with the silencer volume 20, the flow passage part 44 with the silencer volume 24 and the outlet pipe 12. The silencer volume 20 is closed on the outside by a cover 26, and the silencer volume 24 is closed on the outside by a cover 28.

[0060] At the transition 30 of the inlet pipe 10 to the flow path section 40 having the silencer volume 20, a flow deflection device 50 in the form of a step 52 is provided so that the diameter of the flow path 16 of the flow path section 40 having the silencer volume 20 is enlarged.

[0061] The opening 22 is arranged in the flow passage 40 within the protected area of ​​a flow deflector 50 configured as a step 52. The step 52 is arranged to extend circumferentially around the flow passage 16. The flow deflector 50 is configured to be neutral with respect to the intended damping behavior of the acoustic component, i.e. to have substantially no effect on damping.

[0062] To the flow passage portion 44 having the silencer volume 24 Flow path section 40 At the transition 34 , a flow deflector 50 in the form of a step 54 is provided such that the diameter of the flow passage 16 in the flow passage portion 44 with the silencer volume 24 is enlarged.

[0063] The opening 22 is located in the flow passage portions 40, 44 within the protected area of ​​a flow deflector 50 configured as steps 52, 54. The steps 52, 54 are arranged to extend circumferentially around the flow passage 16. The flow deflector 50 is configured to be neutral with respect to the intended damping behavior of the acoustic component, i.e. to have substantially no effect on damping.

[0064] The flow deflector 50 locally deflects the flow in the flow passage parts 40, 44 with the silencer volumes 20, 24 at the transition parts 30, 34 from the opening 22 towards the centre of the flow passage 16 in such a way that the flow separates from the opening 22 and reaches the wall of the flow passage 16 only at some axial distance from the step parts 52, 54, where the opening is no longer present. For this purpose, it is particularly advantageous for the step parts 52, 54 to be configured with sharp edges.

[0065] In this embodiment, the flow deflector 50 faces outwardly. Thus, the opening 22 is at a greater distance to the longitudinal axis 60 than the wall of the inlet pipe 10.

[0066] However, the flow deflector 50 may also be provided inwardly, for example in the form of circumferentially extending or intermittent stays about the flow passage 16 .

[0067] The increase in step height or diameter may be practically tailored to the boundary conditions of the flow through the acoustic component 100 .

[0068] The outflow pipe 12 has the same inner diameter as the flow passage portion 44 having the silencer volume 24. If necessary, the outflow pipe 12 may have a larger inner diameter than the flow passage portion 44 having the silencer volume 24.

[0069] The outer diameters of the covers 26, 28 of the flow passage portions 40, 44 are the same.

[0070] 7A shows a detail of a longitudinal section along the longitudinal axis 60 of the acoustic component 100 of FIG 1. Between the inlet pipe 10 and the outlet pipe 12 of the flow passage 16, a flow passage section 40 having a silencer volume 20 is arranged, and in the flow passage section 40, the silencer volume 20 communicates with the flow passage 16 via an opening 22.

[0071] At the transition 30 of the inlet pipe 10 to the flow path section 40 having the silencer volume 20, a flow deflection device 50 in the form of a step 52 is provided so that the diameter of the flow path 16 of the flow path section 40 having the silencer volume 20 is enlarged.

[0072] The opening 22 is located in the flow passage 40 within the protected area of ​​a flow deflector 50 configured as a step 52 .

[0073] The flow deflector 50 has the effect of separating the core flow 45 from the wall of the flow passage 16 such that the core flow 45 leaves the opening 22 and re-contacts the wall of the flow passage 16 only some axial distance away from the flow deflector 50 where the opening 22 is no longer present. 40 The openings 22 are located outside the core flow 45 and do not receive any inflow. 22 is located in the wake region 48 of the flow, also known as the dead zone. The wake region 48 is defined by an imaginary separation surface 47 from the core flow 45. In the wake region, individual vortices 46 may develop, but have no acoustic effect.

[0074] 8 shows a schematic representation of an air duct 200 in the form of an intake air duct for an internal combustion engine, comprising an inventive acoustic component 100 according to an embodiment of the invention. To Seki Advantageously, even when the air flow rate in the air duct 200 is high, the acoustic component 100 can avoid noise such as whistling.

[0075] The acoustic component 100 may be located downstream of the turbocharger 90 in the high pressure section of the air duct, or upstream in the low pressure section.

Claims

1. An acoustic component (100) comprising a flow path (16) for a fluid, At least one flow path section (40, 44) having a silencer volume (20, 24) is disposed between the inlet pipe (10) and the outlet pipe (12) of the flow path (16), and in the flow path section (40, 44), the silencer volume (20, 24) is in communication with the flow path (16) via an opening (22); at least one flow deflector (50) is provided in the flow path portion (40, 44) having at least the silencer volume (20, 24) to deflect the flow of fluid in the flow path portion (40, 44) having the silencer volume (20, 24) away from the opening (22); the flow deflector (50) includes at least one longitudinal stay (56) projecting into the flow passage (16) and extending axially along the flow passage portions (40, 44) along a longitudinal axis (60); The longitudinal stay (56) has a surface of the longitudinal stay (56) facing the central axis of the flow passage portion (40, 44) that has a curvature equal to a curvature of an inner wall surface of the flow passage portion (40, 44); The opening (22) of the flow passage portion (40, 44) is disposed in a protected area (48) of the flow deflector (50).

2. 2. The acoustic component of claim 1, wherein the at least one flow deflector (50) is provided at least at a transition (30, 34) of the inlet pipe (10) to the flow passage portion (40, 44) having the silencer volume (20, 24).

3. 3. An acoustic component according to claim 1 or 2, wherein the flow deflector (50) is configured to have no effect on the damping effect of the acoustic component (100) on noise caused by the fluid flow.

4. The acoustic component according to any one of claims 1 to 3, wherein the outflow pipe (12) has a diameter equal to or larger than that of the flow passage portion (40, 44) having the silencer volume (20, 24) and / or a cross section equal to or larger than that of the flow passage portion (40, 44).

5. An acoustic component according to any one of the preceding claims, wherein the flow passage (16) in the flow passage portion (40, 44) has a larger diameter and / or cross section than in the inlet pipe (10).

6. The acoustic component of any one of claims 1 to 5, wherein the flow deflector (50) comprises at least one step (52, 54).

7. The acoustic component of claim 6, wherein the steps (52, 54) are configured to have substantially sharp edges.

8. An acoustic component according to claim 6 or 7, wherein the steps (52, 54) are arranged to extend circumferentially around the flow passage (16).

9. An acoustic component according to any one of the preceding claims, wherein the at least one longitudinal stay (56) extends in the axial direction (60) over at least the axial extent of the opening (22).

10. The acoustic component according to any one of claims 1 to 9, wherein a plurality of longitudinal stays (56) are arranged around the longitudinal axis (60) in the flow passage portion (40, 44).

11. The acoustic component according to any one of claims 1 to 10, wherein two or more flow deflection devices (50) with the flow passage portion (40, 44) having the silencer volume (20, 24) are arranged consecutively along the longitudinal axis (60).

12. An air duct (200) for an internal combustion engine comprising an acoustic component (100) according to any one of claims 1 to 11, An air duct, wherein the acoustic component (100) is located on the clean air side of the air inlet, or wherein the acoustic component (100) is located on the untreated air side of the air inlet.

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