Exhaust restriction tube for a vehicle muffler

Abstract

The present disclosure provides an "Exhaust Restriction Tube for Vehicle Muffler". A vehicle exhaust system is provided. The exhaust system can include a muffler including a housing, an inlet pipe extending therethrough, and an outlet pipe partially disposed therein. The exhaust system can also include a restriction tube that can have a tapered body inserted within an end of the outlet pipe, the tapered body disposed between a baffle and a wall of the housing. The restriction tube can also include an inlet portion flared from the tapered body, the inlet portion configured to attenuate noise of exhaust gas entering the outlet pipe.

Description

Technical Field

[0001] This disclosure generally relates to a vehicle exhaust system, and more specifically, to the connection between an inlet pipe and a muffler. Background Technology

[0002] Vehicles, especially those equipped with internal combustion engines, typically include an exhaust system for directing exhaust gas from the engine to a desired outlet. The exhaust system may include one or more exhaust pipes that connect to a manifold or header and extend to a muffler. A muffler is typically used as a sound attenuation device and is designed to reduce the loudness of the sound pressure produced by the engine. Generally, the muffler receives exhaust gas from an inlet pipe and exits the gas through an outlet pipe or tailpipe.

[0003] An active exhaust system may include a muffler, which includes one or more pipes and one or more valves that can be opened or closed to change the acoustic characteristics of the exhaust. Summary of the Invention

[0004] According to one embodiment of this disclosure, a vehicle exhaust system is provided. The exhaust system may include a muffler comprising a housing, an inlet pipe extending therethrough, and an outlet pipe partially disposed therein. The exhaust system may also include a throttle tube having a tapered body inserted into an end of the outlet pipe, the tapered body being disposed between a baffle and a wall of the housing. The throttle tube may further include an inlet portion flared from the tapered body, the inlet portion being configured to attenuate noise from exhaust entering the outlet pipe.

[0005] According to another embodiment of this disclosure, a vehicle exhaust system is provided. The exhaust system may include a muffler comprising a housing, an inlet pipe extending therethrough, and an outlet pipe partially disposed within the housing. The exhaust system may also include a funnel-shaped element, which may include an inlet portion, an outlet portion, and a flared portion extending between the two. The flared portion may be configured to reduce the sound pressure of exhaust gas flowing from the inlet portion into the outlet pipe.

[0006] According to yet another embodiment of this disclosure, a vehicle muffler assembly is provided. The muffler assembly may include a housing, a perforated inlet pipe extending therethrough, and an outlet pipe partially disposed within the housing. The muffler assembly may further include a reducer comprising a tapered body inserted into an end of the outlet pipe and an inlet portion flaring out from the tapered body, the tapered body being disposed between a baffle and a wall of the housing, and the inlet portion being configured to attenuate noise from exhaust gas entering the outlet pipe. Attached Figure Description

[0007] Figure 1This is a top view of an exemplary exhaust system.

[0008] Figure 2 This is a top view of the muffler assembly according to the first embodiment.

[0009] Figure 2A It is along Figure 2 The cross-sectional view taken from line 2A in the diagram.

[0010] Figure 3 This is a top view of the muffler assembly according to the second embodiment.

[0011] Figure 3A It is along Figure 3 The cross-sectional view taken from line 3A in the diagram.

[0012] Figure 4 This is a top view of the muffler assembly according to the third embodiment.

[0013] Figure 4A It is along Figure 4 The cross-sectional view taken from line 4A in the diagram.

[0014] Figure 5 This is a top view of the muffler assembly according to the fourth embodiment.

[0015] Figure 5A It is along Figure 5 The cross-sectional view taken from line 5A in the diagram.

[0016] Figure 6 It is a graph of sound pressure relative to a first engine speed range associated with several embodiments of this disclosure.

[0017] Figure 7 It is a graph of sound pressure relative to the second engine speed range associated with several embodiments of this disclosure.

[0018] As requested, detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely illustrative of the invention, which may be embodied in a wide variety of alternative forms. The drawings are not necessarily drawn to scale; some features may be enlarged or minimized to show details of specific components. Therefore, the specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art to employ the invention in different ways.

[0019] Vehicle exhaust systems typically employ mufflers to reduce and control the loudness (in decibels) of the sound pressure generated by engine exhaust. A muffler includes a housing, an inlet pipe (e.g., a tube, cylinder, channel), and an outlet pipe (e.g., a tube, cylinder, channel). The inlet pipe is fluidly connected to the engine and facilitates exhaust flow to the muffler housing. A portion or a first end of the tailpipe is disposed within the housing, and a second end extends out of the muffler. The muffler may also include one or more baffles or plates that divide the muffler housing into multiple (e.g., first and second) chambers. Figures 2 to 5 Each of the two muffler housings is shown. A muffler for an active exhaust system may include one or more valves operable to control airflow between the first and second chambers or through inlet and outlet pipes. In certain situations, a low-pitched rumble under overload conditions may occur when exhaust flows from the muffler housing into the outlet pipe. This low-pitched rumble under overload conditions is caused by a Helmholtz pattern resulting from the geometry of the outlet pipe and the volume of the muffler housing.

[0020] Helmholtz mode, or resonance, refers to the phenomenon of air resonance within a cavity, such as when air blows across the top of an empty bottle, creating noise. This resonance depends on the volume of the bottle, the length of the bottle's neck, and the cross-sectional area of ​​the neck. When it comes to muffler assemblies, Helmholtz resonance depends on the volume of the first chamber containing the inlet portion of the outlet pipe, the diameter of the outlet pipe, and the distance between the inlet end (e.g., the proximal end) and the outlet end (e.g., the distal end).

[0021] As exhaust gas travels from the first chamber through the outlet pipe, the low rumble under overload conditions can be reduced by blocking the exhaust sound waves. Reducing the diameter of the outlet pipe's inlet end increases the acoustic impedance. This reduction in diameter can be achieved using an orifice plate located on a portion of the outlet pipe. However, the orifice plate abruptly reduces the flow area and causes flow separation, which is typically associated with air impingement or flow noise. Secondly, orifice plates often include punched holes defining sharp edges (e.g., 80-90°). These sharp edges cause turbulence in the exhaust gas, which is also associated with air impingement or flow noise. Finally, the reduced flow area through the orifice plate increases the exhaust velocity, resulting in a pressure drop after the orifice plate, another cause of air impingement or flow noise.

[0022] To suppress or limit air impingement noise while reducing the low-pitched rumble under overload conditions, a throttling tube or funnel-shaped element is used to alter the exhaust flow (e.g., pressure, acceleration, velocity, etc.) as it enters the outlet pipe. The throttling tube may include a tapered body that inserts into the inlet end of the outlet pipe. The inlet portion of the tapered body may flare outwards to control the flow and minimize the increase in exhaust air impingement or flow noise as the exhaust flows through the outlet pipe.

[0023] refer toFigure 1 The diagram illustrates an exhaust assembly 10 including two mufflers 16. The exhaust assembly 10 includes an inlet pipe connected to a Y-shaped splitter 12, which in turn connects to two I-shaped pipes 14. Each I-shaped pipe 14 extends to an inlet pipe 21, which continues into the muffler 16. The muffler 16 may include one or more outlet pipes or tailpipes 18. The exhaust assembly 10 can be actively controlled (e.g., active exhaust). An actively controlled exhaust assembly includes one or more valves actuated by a controller or processor. Opening or closing the valves when deemed appropriate by a user or operator alters the exhaust sound (e.g., sound pressure level, frequency, etc.).

[0024] refer to Figure 2 and Figure 2A A muffler assembly 16 and a throttle tube 26 are provided. The muffler assembly 16 includes a housing 17 extending between a first wall 18a and a second wall 18b. A metal partition or plate, such as a baffle 22, divides the housing 17 into a first part 26 and a second part 27. A tuner, such as a Helmholtz tuner 23, is disposed within the housing 17 and extends through the baffle 22. The tuner 23 can modify the acoustic performance of the muffler 16. An inlet tube 21 extends from an I-tube 14 ( Figure 1 The inlet pipe 21 extends through the first wall 18a, through the baffle 22, and through the second wall 18b. A valve (not shown) may be disposed within the second portion 27 of the inlet pipe 21 between the baffle 22 and the second wall 18b. Alternatively, the valve may be disposed within the tailpipe 18, such that it is outside the muffler. The valve may be opened, closed, or rotated to a position between an open and a closed position to alter the acoustic performance of the muffler. A portion of the inlet pipe 21 disposed within the first portion 26 of the housing 17 includes a hole or perforation 24 to allow exhaust gas to exit the inlet pipe 21. A portion of the inlet pipe 21 disposed within the second portion 27 of the housing 17 includes a hole or perforation to reduce air impingement or flow noise sound pressure before the exhaust gas exits the muffler.

[0025] The muffler assembly 16 also includes an outlet pipe 20 and a throttling pipe 26 assembled therein. The outlet pipe 20 includes a first end 20a disposed within a first portion of the housing 26 and a second end 20b extending through a second wall 18b. The first end 20a of the outlet pipe 20 is spaced apart from the first wall 18a of the muffler 16 by a distance X1. The throttling pipe 26 is assembled to and inserted into the first end 20a of the outlet pipe 20. When exhaust flows through the inlet pipe 21, with or without one or more of the aforementioned valves closed or open, the exhaust enters the first portion 26 through the orifice or perforation 24. The exhaust then passes through the throttling pipe 26 through the outlet pipe 20 from the first end 20a to the second end 20b.

[0026] As mentioned above, without the throttle tube 26, the sound pressure level of the low rumble or noise under overload conditions may be unacceptable. The noise under overload conditions is particularly noticeable when the engine reaches speeds between 1,000 rpm and 2,500 rpm.

[0027] Now for specific reference Figure 2A A partial cross-sectional view of the outlet pipe 20 and the throttling pipe 26 is shown. The throttling pipe 26 includes a flared portion 36 angled away from the outlet pipe 20 to define an inner diameter D1. The flared portion 36 extends from a body, such as a nozzle or a tapered body 30, which includes an intermediate portion 34 disposed within the outlet pipe 20. The intermediate portion 34 defines an inner diameter D2 smaller than the inner diameter D1 of the flared portion 36. A transition portion 32 extends between the intermediate portion and a distal portion 28. The distal portion 28 defines an inner diameter D3 smaller than the inner diameter D2. The diameter of the throttling pipe further decreases relative to the flared portion 36 between the intermediate portion 34 and the distal portion 28.

[0028] The reduction in diameter between the inner diameter D1 of the flared portion 36, the inner diameter D2 of the intermediate portion 34, and the inner diameter D3 of the distal portion attenuates the overall sound level and the low-pitched rumble or noise under overload conditions. The reduced diameter hinders sound waves from passing through the throttle tube 26 and then through the outlet tube 20. Furthermore, the reduced diameter (e.g., D1, D2, and D3) increases the tube's expansion volume, resulting in increased sound wave reflection. Increased sound wave reflection attenuates the sound level. Of course, the overall reduction in the diameter of the throttle tube 26 leads to a reduction in its cross-sectional area. When the cross-sectional area of ​​the Helmholtz neck (e.g., the throttle tube 26) decreases, the frequency of sound waves passing through the neck decreases.

[0029] The flared portion 36 and the tapered body 30 are each configured to minimize flow noise or air impact noise. The flared portion 36 can remove or reduce flow separation of the exhaust gas before it enters the tapered body 30. The tapered body allows the flow velocity to gradually stabilize to reduce turbulence of the traveling gas. Finally, with the orifice plate ( Figure 1 In comparison, the pressure drop when the gas leaves the throttling tube is more gradual.

[0030] The throttling tube 26 may also include a flange 38 extending from the flared portion 36. The flange 38 may be folded back toward the flared portion 36 to define a radius R1. The flange 38 may also include a connecting end 40, which is formed to abut against the outside of the outlet tube when the throttling tube is assembled to the outlet tube 20. The connecting end 40 may be attached to the outlet tube 20 by one or more welds or structural adhesives. In another embodiment, the intermediate portion 34 and the connecting end 40 may clamp the outlet tube in between to connect the throttling tube to the outlet tube in a press-fit state.

[0031] In another embodiment, the body or nozzle 30 of the throttle tube 26 may have a constant diameter. More specifically, the intermediate portion and inner diameter D2 extend along the length of the body. Alternatively, the body or nozzle may be more... Figure 2A The main body 30 shown is further tapered.

[0032] In another embodiment, the intermediate portion 34 of the throttling tube 26 is disposed along the inner wall of the outlet tube 20. In this embodiment, the throttling tube 26 is not attached to the connecting end 40. Instead, the intermediate portion 34 is attached to the inner tube by one or more welds or structural adhesives.

[0033] The following are Figures 3 to 5A The discussion describes additional embodiments. Some elements of the additional embodiments are the same as those of the first embodiment described above. These same elements have the same features and functions as those of the elements in the first embodiment, and therefore the description of those elements described above applies to the description of the additional embodiments discussed below.

[0034] Reference Figure 3 and Figure 3A A muffler assembly 50 including a throttle tube 54 is provided according to a second embodiment. In this embodiment, the housing 52 is more... Figure 2 The housing 17 described herein is longer. Furthermore, the throttle tube 54 itself is also longer to provide additional order control of the acoustic characteristics associated with the exhaust flow through the muffler assembly 50. Because the housing 52 is longer than the housing 17, the first end 20a of the outlet pipe 20 is spaced apart from the first wall 18a by a distance X2. This distance X2 is greater than... Figure 2 The distance X1 is shown. The throttle tube 54 includes a flared portion 36 defining an inner diameter D3. The flared portion 36 includes a radius R2 and defines the inner diameter D3. The body 56 extends from the flared portion 36 to the folded end 60. The folded end defines a third radius R3 extending between the body 56 and the connecting end 62. Each of radii R2 and R3 reduces air impact noise from exhaust gas moving from the first portion 26 through the second portion 27.

[0035] refer to Figure 4 and Figure 4AA muffler assembly 68 including a throttle tube 70 is provided according to a third embodiment of the invention. The throttle tube 70 may be configured to accommodate or retain a filling material such as alkali-free glass 84 against an outlet pipe 20. When exhaust flows through the throttle tube 70, the alkali-free glass 84 may absorb or reduce exhaust noise (e.g., air impingement noise, overload condition noise, etc.). The throttle tube 70 includes an inlet connecting wall 72 disposed along the inner wall of the outlet pipe and adjacent to a first end 20a of the outlet pipe. The throttle tube 70 also includes an inlet flange portion 82 extending from the inlet connecting wall 72 to an intermediate wall 76. The inlet connecting wall defines a diameter D1, and the intermediate wall 76 defines a diameter D2 smaller than the diameter D1. A distal connecting wall defines a third diameter D3, which may be approximately equal to the diameter D1. The various diameters D1, D2, and D3 define a passage. The volume of the passage decreases between D1 and D2 to facilitate controlled flow of exhaust as exhaust enters and moves through the throttle tube 70. The exhaust pressure is highest when the exhaust is within the intermediate wall. This pressure acts on the exhaust, causing it to move towards the filling material or alkali-free glass 84. The volume of the channel gradually increases between the intermediate wall and the distal wall 74. This gradual increase in volume facilitates controlled flow of the exhaust as it moves through the throttle tube 70 and into the outlet tube 20. Similarly, the controlled flow into and out of the throttle tube 70 reduces the sound pressure associated with the exhaust flow within the muffler assembly.

[0036] The intermediate wall 76 includes one or more holes or perforations 78. The acoustic waves from the exhaust pass through the perforations 78 to reach the alkali-free glass material 84. The throttling tube also includes a distal flange portion 80 extending from the intermediate portion to the distal connecting member 74. The distal connecting member 74 and the inlet connecting member 72 can be attached to the outlet pipe 20 via one or more welds or structural adhesives.

[0037] Reference Figure 5 and Figure 5A A muffler assembly 100 is provided, including a throttle tube 102 according to a fourth embodiment of the present disclosure. The throttle tube 102 includes an inlet wall 104 defining a diameter D1 and an outlet wall 108 defining a second diameter D2 smaller than D1. The inlet wall 104 is connected to a connecting wall 106 by a radius R4. The outlet wall 108 extends from a radius R5 and the connecting wall 106. A first end 20a of the outlet tube 20 can be attached to the connecting wall 106 of the throttle tube 102 by one or more welds or structural adhesives. The throttle tube 102 can be manufactured by stamping or pipe forming in conjunction with the inlet end 104. Compared to the previous embodiments described above, the geometry of the throttle tube 102 can be a more cost-effective design.

[0038] refer to Figure 6A graph of sound pressure levels versus engine speeds associated with several embodiments of the present disclosure is provided. The previously described air impact noise is generally associated with sound pressure levels between 3,500 rpm and 6,500 rpm. Decibels (dBA) are represented by the vertical axis, and engine speeds (rpm) are represented by the horizontal axis. Line S1 represents the decibel level (dBA) of the muffler assembly 100 relative to engine speed without the throttle tube 102. Line S1 reaches 118.1 dBA at approximately 5,000 rpm. Line S2 represents... Figures 5 to 5A The fourth embodiment shown has a muffler assembly 100 and throttle tube 102 with decibel levels (dBA). Line S2 reaches approximately 122 dBA at 5,000 RPM. Figure 7 As shown, when the muffler assembly 100 including the throttle tube 102 increases the air impact noise by 3 dBA, the low rumbling noise under overload conditions is reduced.

[0039] refer to Figure 7 This provides another graph of sound pressure levels relative to engine speed associated with several embodiments of the present disclosure. The previously described overload operating noise is generally associated with sound pressure levels between 1,100 rpm and 2,000 rpm. Decibels (dBA) are represented by the vertical axis, and engine speed (rpm) is represented by the horizontal axis. Line S1 represents the sound pressure level of the muffler assembly 100 relative to engine speed without the throttle tube 102. Line S1 reaches 80 dBA at approximately 1,150 rpm and 95.2 dBA at approximately 1,625 rpm. Line S2 represents... Figures 5 to 5A The fourth embodiment shown has the following decibel (dBA) levels for the muffler assembly 100 and throttle tube 102. Line S2 reaches 78 dBA at approximately 1,151 rpm and 86.2 dBA at approximately 1,625 rpm. Adding the throttle tube 102 reduces the sound pressure by 2 dBA (2.5%) at 1,151 rpm and by 9 dBA (11.3%) at 1,625 rpm.

[0040] While exemplary embodiments have been described above, these embodiments are not intended to describe all possible forms of the invention. Rather, the terms used herein are descriptive rather than restrictive, and it should be understood that various changes may be made without departing from the spirit and scope of the invention. Furthermore, features of various implementation embodiments may be combined to form further embodiments of the invention.

[0041] According to the present invention, a vehicle exhaust system is provided, the vehicle exhaust system having: a muffler including a housing, an inlet pipe extending therethrough and an outlet pipe partially disposed therein; and a throttle pipe including a tapered body inserted into an end of the outlet pipe and an inlet portion flared out from the tapered body, the tapered body being disposed between a baffle and a wall of the housing, the inlet portion being configured to attenuate noise of exhaust entering the outlet pipe.

[0042] According to one embodiment, the tapered body includes a middle portion and a distal portion, the middle portion being connected to the inlet portion and defining a first diameter, and the distal portion defining a second diameter smaller than the first diameter, such that the resistance of the exhaust increases as it passes through the funnel-shaped throttling tube to attenuate noise associated with the exhaust.

[0043] According to one embodiment, the intermediate portion and the distal portion are connected by a tapered wall, such that the velocity increases when the exhaust gas converges through the throttling tube.

[0044] According to one embodiment, the inlet portion includes an end portion that folds back toward the tapering body, such that the end portion is attached to the outer periphery of the outlet pipe.

[0045] According to one embodiment, the inlet pipe is partially perforated and configured to discharge exhaust gas from the inlet pipe to the inlet portion of the throttling pipe.

[0046] According to one embodiment, the tapering body includes a proximal portion extending from the inlet portion, and wherein the proximal portion is disposed along the inner wall of the outlet pipe.

[0047] According to one embodiment, the noise is associated with engine speed.

[0048] According to the present invention, a vehicle exhaust system is provided, the vehicle exhaust system having: a muffler including a housing, a perforated inlet pipe extending therethrough and an outlet pipe partially disposed within the housing; and a funnel-shaped element including an inlet portion, an outlet portion and a flared portion extending therebetween, the flared portion being configured to reduce the sound pressure of exhaust gas flowing from the inlet portion into the outlet pipe.

[0049] According to one embodiment, the flared portion is configured to attenuate exhaust noise generated when the engine speed exceeds 3,000 rpm.

[0050] According to one embodiment, the inlet portion defines a first diameter, and the outlet portion defines a second diameter smaller than the first diameter, such that the acceleration of the exhaust gas decreases as it flows through the funnel-shaped element, thereby attenuating the noise associated with the exhaust gas.

[0051] According to one embodiment, the inlet portion and the outlet portion cooperate to attenuate exhaust noise generated when the engine speed is between 1,000 rpm and 3,000 rpm.

[0052] According to one embodiment, the inner diameter of the outlet pipe is smaller than the first diameter and larger than the second diameter.

[0053] According to the present invention, a vehicle muffler assembly is provided, the vehicle muffler assembly having: a housing, a perforated inlet pipe extending therethrough and an outlet pipe partially disposed within the housing; and a reducer including a tapered body inserted into an end of the outlet pipe and an inlet portion flared out from the tapered body, the tapered body being disposed between a baffle and a wall of the housing, the inlet portion being configured to attenuate noise from exhaust gas entering the outlet pipe.

[0054] According to one embodiment, the reducer includes an intermediate portion and a distal portion, the intermediate portion being connected to the inlet portion and defining a first diameter, and the distal portion defining a second diameter greater than the first diameter, such that the acceleration of the exhaust gas is reduced when the exhaust gas passes through the reducer, thereby attenuating the noise associated with the exhaust gas.

[0055] According to one embodiment, the inlet portion defines a third diameter that is larger than the first diameter.

[0056] According to one embodiment, the inlet portion and the distal portion are each positioned along a portion of the inner periphery of the outlet pipe, and the intermediate portion is spaced apart from the portion of the inner periphery of the outlet pipe to define a cavity.

[0057] According to one embodiment, the invention is further characterized by a filling material disposed within the cavity and configured to reduce the acoustic waves of the exhaust gas.

[0058] According to one embodiment, the noise is associated with engine speed.

Claims

1. A vehicle exhaust system, comprising: A silencer includes a housing having a first end and a second end, a baffle disposed within the housing, an inlet pipe, and an outlet pipe, wherein the baffle includes a first side facing the first end and a second side facing the second end, the first side of the baffle and the first end of the housing defining a first internal portion of the housing, the inlet pipe extending through the first end, the baffle, and the second end, and the outlet pipe including a first outlet end disposed within the first internal portion and a second outlet end extending through the second end of the housing; and A throttling tube includes a tapered body inserted into the first outlet end of the outlet pipe, an inlet portion flared from the tapered body, and a distal portion terminating before the baffle, wherein the throttling tube is configured to attenuate noise from exhaust gas entering the outlet pipe from the first internal portion of the housing.

2. The vehicle exhaust system of claim 1, wherein the tapering body includes a middle portion and a distal portion, the middle portion being connected to the inlet portion and defining a first diameter, and the distal portion defining a second diameter smaller than the first diameter, such that the impedance of the exhaust increases as it passes through the throttle tube to attenuate noise associated with the exhaust.

3. The vehicle exhaust system of claim 2, wherein the intermediate portion and the distal portion are connected by a tapered wall such that the exhaust gas increases in velocity as it passes through the throttle tube.

4. The vehicle exhaust system of claim 1, wherein the inlet portion includes an end portion that folds back toward the tapering body, such that the end portion is attached to the outer periphery of the outlet pipe.

5. The vehicle exhaust system of claim 1, wherein the inlet pipe is partially perforated and configured to discharge exhaust gas from the inlet pipe to the inlet portion of the throttle pipe.

6. The vehicle exhaust system of claim 1, wherein the tapering body includes a proximal portion extending from the inlet portion, and wherein the proximal portion is disposed along the inner wall of the outlet pipe.

7. The vehicle exhaust system of claim 1, wherein the noise is associated with engine speed.

8. A vehicle exhaust system, comprising: A silencer includes a housing, a baffle, an inlet pipe extending through the housing, and an outlet pipe, wherein the housing includes a first portion and a second portion, the baffle is disposed within the housing and divides the housing into the first portion and the second portion, the inlet pipe includes a perforated section disposed within the first portion of the housing, and the outlet pipe includes a first end disposed within the first portion of the housing, the outlet pipe being parallel to and offset from the inlet pipe; and A funnel-shaped element is disposed in the first end of the outlet pipe and includes an inlet portion, an outlet portion, and a flared portion extending between the two, the flared portion being configured to reduce the sound pressure of exhaust gas flowing into the outlet pipe from the perforated section; wherein the inlet portion defines a first diameter, and the outlet portion defines a second diameter smaller than the first diameter, such that the acceleration of the exhaust gas decreases as it flows through the funnel-shaped element to attenuate noise associated with the exhaust gas, and wherein the outlet pipe defines an inner diameter smaller than the first diameter and larger than the second diameter.

9. The vehicle exhaust system of claim 8, wherein the flare portion is configured to attenuate exhaust noise generated when the engine speed exceeds 3,000 rpm.

10. The vehicle exhaust system of claim 8, wherein the inlet portion and the outlet portion cooperate to attenuate exhaust noise generated at engine speeds between 1,000 rpm and 3,000 rpm.

11. A vehicle muffler assembly, comprising: A housing, a baffle, an inlet pipe extending through the housing, and an outlet pipe, wherein the housing includes a first portion and a second portion, the baffle is disposed in the housing and divides the housing into the first portion and the second portion, the inlet pipe includes a perforated section disposed in the first portion of the housing, the outlet pipe includes a first end disposed within the first portion of the housing, and the outlet pipe is parallel to and offset from the inlet pipe; and A reducer includes a tapered body inserted into the first end of the outlet pipe and an inlet portion flared out from the tapered body, the tapered body being disposed between the baffle and the wall of the housing, and the inlet portion being configured to attenuate noise from exhaust gas entering the outlet pipe.

12. The vehicle muffler assembly of claim 11, wherein the reducer includes an intermediate portion and a distal portion, the intermediate portion being connected to the inlet portion and defining a first diameter, and the distal portion defining a second diameter greater than the first diameter, such that the acceleration of the exhaust gas is reduced as exhaust gas passes through the reducer, thereby attenuating noise associated with the exhaust gas.

13. The vehicle muffler assembly of claim 12, wherein the inlet portion defines a third diameter greater than the first diameter.

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