EXHAUST MUFFLER

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority to and the benefit of U.S. Provisional Application No. 63/701,261 filed Sep. 30, 2024, now allowed, which is hereby incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention generally relates to an exhaust muffler, used in particular for dampening noise entailed by the emission of exhaust gases from a vehicle exhaust system.

BACKGROUND

A vehicle exhaust system directs exhaust gases generated by an internal combustion engine to external environment. The exhaust system can include various components, such as pipes, converters, catalysts, filters, and the like. During operation of the exhaust system, as a result of resonating frequencies, the components can generate undesirable noise. Different methods have been employed to address this issue. For example, the components, such as mufflers, resonators, valves, and the like, have been incorporated into the exhaust system to attenuate certain resonance frequencies generated by the engine or the exhaust system. However, such additional components are expensive and increase weight of the exhaust system. Also, adding new components into the exhaust system can introduce new sources of undesirable noise generation.

One such method to reduce the undesirable noise is a Standing Wave Management (SWM) technology. The SWM includes an opening provided on an exhaust pipe. The opening provides a secondary exhaust leak path for sound to exit the exhaust pipe and minimizes leakage of the exhaust gases through the opening. The SWM utilizes a series of holes to allow sound waves to exit the exhaust pipe while limiting leakage of the exhaust gases.

In some implementations, a hood is coupled over the series of holes (e.g., via welding, adhesion, fastening, etc.) to define a reservoir for the exhaust gases exiting from the holes. The hood acts as a volume device that ensures that little to no exhaust gases exiting from the holes is exhausted to atmosphere surrounding the vehicle exhaust system.

In some implementations, the series of holes can be covered with a microperforated material. In order to achieve a desired noise attenuation, the holes have to be relatively large in size. However, the microperforated material is very thin and is not as structurally sound as a solid pipe wall of the exhaust pipe. As such, creating holes in the microperforated material can adversely affect durability of the microperforated material. Additionally, if relatively larger holes are cut into the exhaust pipe and covered with the microperforated material, durability of the exhaust pipe can also be adversely affected. Another concern is with grazing flow that can occur across a surface of the microperforated material. The acoustic properties of the microperforated material can change when the exhaust gases flow across the surface of the microperforated material. This can often reduce an ability of an acoustic wave to propagate through the micro perforations, which can limit the damping effect.

An example of a muffler is provided in U.S. Pat. No. 11,614,009 B2 (hereinafter referred to as '009 reference). The '009 reference provides a vehicle exhaust system featuring a tubular component with ridges and spaced apertures to control acoustic modes and exhaust gas flow. The system aims to reduce emissions and noise while improving efficiency.

Another example of the muffler is provided in U.S. Pat. No. 11,808,186 B2 (hereinafter referred to as '186 reference). The '186 reference provides a vehicle exhaust system designed to hold diverted flow in a reservoir created by an exhaust component and a surface component. This innovative system aims to prevent leaked mass flow and improve the efficiency of the exhaust process.

SUMMARY

According to an aspect, an exhaust muffler is provided. The exhaust muffler comprises a hollow body defining a first set of apertures on the hollow body. The exhaust muffler further comprises an exhaust pipe having an inlet opening and an outlet opening spaced apart from the inlet opening. The exhaust pipe is disposed at least partially within the hollow body. The exhaust pipe has an inner surface and an outer surface disposed opposite to the inner surface, wherein the inner surface defines a primary exhaust gas flow path extending along from the inlet opening to the outlet opening; and wherein the exhaust pipe defines a second set of apertures and a third set of apertures on the exhaust pipe such that the exhaust gases flowing through the exhaust pipe flow out of the exhaust pipe within the hollow body and/or flow back into the exhaust pipe from the hollow body through the second set of apertures and the third set of apertures. Further, at least one divider defines an opening to allow the exhaust pipe to pass therethrough, wherein the at least one divider divides the hollow body into at least a first chamber and a second chamber operatively configured for sound attenuation, wherein the first chamber is engaged with the second chamber. The first chamber defines a reservoir fluidly associated with the primary exhaust gas flow path via the second set of apertures, and to the environment via the first set of apertures, and wherein the second chamber is fluidly associated with the primary exhaust gas flow path via the third set of apertures.

The exhaust muffler advantageously combines the three sound attenuation technologies, i.e., Standing Wave Management (SWM) technology that works to attenuate low frequency standing waves in the exhaust pipe using the second set of apertures; Pulsation Cover technology that works to limit the leakage of exhaust gas flow from the second set of apertures to external environment; and the roving technology that works to attenuate the high frequency air rush.

Further, the exhaust muffler comprises at least one divider such that the exhaust pipe can securely rest on the opening of the at least one divider. In other words, the at least one divider removably holds and/or supports the exhaust pipe in a desired orientation at least partially within the hollow body. Further, the at least one divider divides the hollow body into at least the first chamber and the second chamber such the Standing Wave Management (SWM) technology; Pulsation Cover technology; and the roving technology can be implemented with the exhaust muffler.

Further, the at least first chamber and the second chamber can be axially or laterally offset relative to each other, wherein the axial or lateral direction can be taken relative to the longitudinal direction of the hollow body. Further, the at least first chamber and the second chamber can be more than three chambers incorporating the Standing Wave Management (SWM) technology; Pulsation Cover technology; and the roving technology in any desirable sequence. Further, there can be multiple chambers incorporating either one of the above technologies responsible for sound attenuation.

According to an embodiment of the present invention, the second chamber is filled with absorption material. In other words, the second chamber incorporates the roving technology to attenuate the high frequency air rush. The absorption material, in particular, the sound absorption material can be glass and/or mineral fibers, and/or any other material feasible for soundproofing.

According to an embodiment of the present invention, the second chamber can incorporate any other acoustic device as well. For example, the second chamber can incorporate an expansion can volume, a Helmholtz volume, a quarter wave function, a valve function, or multiple functions together.

According to an embodiment of the present invention, the reservoir defines a reservoir volume, and the second set of apertures define an area such that a minimum reservoir volume to the area ratio is greater than or equal to 100 mm. This ratio between the reservoir volume and the area is critical for substantially preventing leakage of the exhaust gases from the exhaust pipe into the environment via the second set of apertures. Preferably, this ratio can be between 100 mm and 2000 mm.

According to an embodiment of the present invention, the reservoir volume can be engaged with a heat exchanger, x-pipe, and y-pipe, or any other non-acoustic volumes.

According to an embodiment of the present invention, the second chamber is disposed downstream of the reservoir and on an opposite side of the divider separating the second chamber and the reservoir. The second chamber can be filled with the absorption material and can be disposed downstream of the reservoir. However, any other arrangement feasible to attenuate exhaust gas flow noise is within the scope of the present disclosure.

According to an embodiment of the present invention, the third set of apertures is a row of apertures at least partially surrounded by the absorption material in the second chamber. The exhaust pipe defines the third set of apertures on the exhaust pipe such that the exhaust gases flowing through the exhaust pipe flow out of the exhaust pipe within the hollow body and/or flow back into the exhaust pipe from the hollow body through the third set of apertures in order to attenuate the exhaust gas noise.

According to an embodiment of the present invention, the first set of apertures, and/or the second set of apertures, and/or the third set of apertures have apertures of shape similar to a slot. However, the shape can be, but not limited to, circular, oval, polygonal, or elliptical. Further, the area of the first set of apertures, the second set of apertures, and the third set of apertures can be equal or different as per requirement.

According to an embodiment of the present invention, the exhaust pipe has a multi-piece structure joined together by at least one divider. The exhaust pipe can have a unitary or multi-piece structure as per requirement. Further, the exhaust pipe can have a cylindrical shape, V-shape, zig-zag shape, or any other linear or non-linear shape as per requirement.

According to an embodiment of the present invention, the second set of apertures is configured to attenuate low frequency standing waves, in particular ranging from 50-250 Hz. The second of apertures can be configured to break standing waves being produced in the exhaust pipe.

According to an embodiment of the present invention, the second chamber is configured to attenuate high frequency air rush, in particular ranging from 500-2500 Hz. The second chamber can be filled with the roving or absorption material such that the exhaust gases flowing through the exhaust pipe flow out of the exhaust pipe within the second chamber and/or flow back into the exhaust pipe from the second chamber through the third set of apertures in order to attenuate the exhaust gas noise.

According to an embodiment of the present invention, the at least one divider has a fourth set of apertures configured to allow fluid communication between at least two chambers. The fourth set of apertures can have shape and size similar to the first set of apertures, and/or the second set of apertures, and/or the third set of apertures. A part of the diverted flow and/or the flow transversing the secondary exhaust gas flow path can leak through to the second chamber via the fourth set of apertures, thereby substantially preventing exhaust gas leakage to the environment.

Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a schematic representation of a vehicle exhaust system according to an embodiment of the present invention;

FIG. 2 illustrates a perspective view of an exhaust muffler of a vehicle exhaust system according to a first embodiment of the present invention;

FIG. 3 illustrates a cross-sectional view of an exhaust muffler of a vehicle exhaust system according to a first embodiment of the present invention;

FIG. 4 illustrates a perspective view of an exhaust muffler of a vehicle exhaust system according to a second embodiment of the present invention;

FIG. 5 illustrates a cross-sectional view of an exhaust muffler of a vehicle exhaust system according to a second embodiment of the present invention;

FIG. 6 illustrates a cross-sectional view of an exhaust muffler of a vehicle exhaust system according to a third embodiment of the present invention;

FIG. 7 illustrates a schematic view representation an exhaust muffler of a vehicle exhaust system according to a fourth embodiment of the present invention; and

FIG. 8 illustrates a schematic representation of an exhaust muffler of a vehicle exhaust system according to a fifth embodiment of the present invention.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. Referring now to the drawings, like reference numerals designate like or corresponding parts throughout the several views. Referring to FIG. 1, FIG. 1 illustrates a schematic representation of a vehicle exhaust system 100. The vehicle exhaust system 100 is fluidly coupled to an engine 102. The engine 102 can be any internal combustion engine powered by a fuel, such as diesel, gasoline, natural gas, and/or a combination thereof. Accordingly, the vehicle exhaust system 100 receives exhaust gases generated by the engine 102.

The vehicle exhaust system 100 includes a number of downstream exhaust components 104 fluidly coupled to the engine 102. The exhaust components 104 can include a number of systems/components (not shown), such as a Diesel Oxidation Catalyst (DOC), a Diesel Exhaust Fluid (DEF) unit, a Selective Catalytic Reduction (SCR) unit, a particulate filter, an active valve, a passive valve and the like. The exhaust components 104 can be mounted in various different configurations and combinations based on application requirements and/or available packaging space. The exhaust components 104 are adapted to receive the exhaust gases from the engine 102 and direct the exhaust gases to the external atmosphere via a tailpipe 106. The exhaust components 104 are adapted to reduce emissions and control noise.

The vehicle exhaust system 100 also includes an exhaust member 108. The exhaust member 108 is an exhaust muffler 110 (as shown in FIG. 2). The exhaust member 108 can perform noise attenuation. The exhaust member 108 is provided in fluid communication with the exhaust components 104 and the tailpipe 106. In the illustrated embodiment, the exhaust member 108 is disposed downstream of the exhaust components 104 and upstream of the tailpipe 106. In other embodiments, the exhaust member 108 can be disposed in any sequence with respect to each of the exhaust components 104 and/or the tailpipe 106, based on application requirements. The exhaust member 108 is adapted to dampen resonance frequencies generated during operation of the engine 102 and the vehicle exhaust system 100.

FIG. 2 illustrates a perspective view of the exhaust muffler 110 of the vehicle exhaust system 100 according to a first embodiment of the present invention. The exhaust muffler 110 includes a hollow body 112, which is preferably a cylindrical body made from any non-corrosive and durable material e.g. stainless steel. The hollow body 112 further includes end plates 111, 113. Further, the hollow body 112 defines a first set of apertures 118 on the hollow body 112. The first set of apertures 118 is a row of the apertures 118 disposed along the circumference of the hollow body 112. In some embodiments, the first set of apertures 118 is one or more than one row of apertures 118 disposed along the circumference of the hollow body 112. In some embodiments, the first set of apertures 118 are disposed at certain pre-defined positions along the circumference of the hollow body 112. Further, the first set of apertures 118 have shape similar to a slot.

Further, the hollow body 112 includes an exhaust pipe 120. The exhaust pipe 120 includes an inlet opening 114, and an outlet opening 116 spaced apart from the inlet opening 114. The inlet opening 114 and the outlet opening 116 of the exhaust pipe 120 have preferably a circular or oval or trioval cross-section, preferably with a parallel orientation relative to each other. Further, the exhaust pipe 120 is disposed at least partially within the hollow body 112. The exhaust pipe 120 is adapted to allow a flow of exhaust gases therethrough. The exhaust pipe 120 can have length smaller, larger, or equal to the hollow body 112. The exhaust pipe 120 can have a shape similar or dissimilar to the hollow body 112. The exhaust pipe 120 can be made from a material similar or dissimilar to the material of the hollow body 112.

Further, the hollow body 112 includes at least one divider 130. The at least one divider 130 is fixedly or removably coupled to the hollow body 112 in any known manner in the related art. The at least one divider 130 defines an opening 132 to allow the exhaust pipe 120 to pass therethrough and further to support the exhaust pipe 120 in the hollow body 112. In other words, the at least one divider 130 is connected with the exhaust pipe 120 to allow the exhaust pipe 120 to pass therethrough. In some embodiments, the at least one divider 130 includes two similar or dissimilar dividers 130 disposed parallel to each other. In some embodiments, the exhaust pipe 120 has a multi-piece structure joined together by at least one divider 130.

Further, the at least one divider 130 divides the hollow body 112 into at least a first chamber 134 and a second chamber 136 operatively configured for sound attenuation. The first chamber 134 is configured to be engaged with the second chamber 136. The second chamber 136 is disposed downstream of the first chamber 134 and on an opposite side of the divider 130 separating the second chamber 136 and the first chamber 134. The first chamber 134 and the second chamber 136 are respectively defined by the volume between the exhaust pipe 120 and the hollow body 112 on opposite sides of the divider 130. The first chamber 134 and the second chamber 136 can have equal or unequal volumes as per requirement.

Further, the exhaust pipe 120 defines a second set of apertures 126 and a third set of apertures 128 on the exhaust pipe 120 such that the exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the hollow body 112 and/or flow back into the exhaust pipe 120 from the hollow body 112 through the second set of apertures 126 and the third set of apertures 128. In other words, the exhaust gases flowing through the exhaust pipe 120 fluidly associate or communicate with the first chamber 134 and the second chamber 136 via the second set of apertures 126 and the third set of apertures 128 respectively. Further, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 have apertures of shape similar to a slot. However, in some embodiments, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 can have apertures of circular, oval, triangular, square, rectangular, elliptical, or any other shape as per requirement. Further, in some embodiments, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 can have different shapes, and sizes as per requirement.

FIG. 3 illustrates a cross-sectional view of the exhaust muffler 110 of the vehicle exhaust system 100. The exhaust muffler 110 includes the hollow body 112, which defines the first set of apertures 118 on the hollow body 112 proximal to the first chamber 134. Further, the hollow body 112 includes the exhaust pipe 120 having the inlet opening 114, and the outlet opening 116 spaced apart from the inlet opening 114. The exhaust pipe 120 is disposed at least partially within the hollow body 112. The exhaust pipe 120 defines the second set of apertures 126 and the third set of apertures 128 on the exhaust pipe 120 proximal to the first chamber 134 and the second chamber 136 respectively. Further, the second set of apertures 126 is a row of the apertures 126 disposed along the circumference of the exhaust pipe 120. In some embodiments, the second set of apertures 126 is one or more than one row of apertures 126 disposed along the circumference of the exhaust pipe 120 proximal to the first chamber 134. In some embodiments, the second set of apertures 126 are disposed at a certain pre-defined positions along the circumference of the exhaust pipe 120. Further, the third set of apertures 128 is one or more rows of the apertures 128 disposed along the circumference of the exhaust pipe 120 proximal to the second chamber 136.

Further, the exhaust pipe 120 is adapted to allow the flow of exhaust gases therethrough. The exhaust pipe 120 has an inner surface 122 and an outer surface 124 disposed opposite to the inner surface 122 such that the second set of apertures 126 and the third set of apertures 128 extend from the inner surface 122 to the outer surface 124 respectively. Further, the inner surface 122 defines a primary exhaust gas flow path “P” extending along from the inlet opening 114 of the exhaust pipe 120 to the outlet opening 116 of the exhaust pipe 120. The exhaust gases received from the exhaust components 104 travel through the primary exhaust gas flow path “P” in a linear or non-linear manner. Further, the first chamber 134 defines a reservoir 138 fluidly associated with the primary exhaust gas flow path “P” via the second set of apertures 126, and to the environment via the first set of apertures 118. A portion of the exhaust gases travelling through the primary exhaust gas flow path “P” escapes the exhaust pipe 120 via the second set of apertures 126 to enter into the reservoir 138 and break the standing waves. In other words, the second set of apertures 126 is configured to attenuate low frequency standing waves, in particular ranging from 50-250 Hz.

The exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 defines a diverted flow “D” and the reservoir 138 holds the diverted flow “D” within the reservoir 138. The exhaust gases can travel perpendicular or parallel or at any other orientation relative to the primary exhaust gas flow path “P” and through the second set of apertures 126 to define the diverted flow “D”. The reservoir 138 enables the diverted flow “D” to change direction at least once within the reservoir 138. In other words, the diverted flow “D” flows through the reservoir 138 in a first direction “F1” and a second direction “F2” opposite to the first direction “F1”. The first direction “F1” and the second direction “F2” can be parallel, orthogonal, or be at any other orientation relative to the exhaust pipe 120. As illustrated in FIG. 3, the first direction “F1” and the second direction “F2” are parallel to the exhaust pipe 120. In other words, some of the diverted flow “D” is drawn back into the exhaust pipe 120 with the suction flow, to ensure that little to none of the diverted flow “D” becomes a leaked mass flow. However, in order to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow, a ratio between a minimum reservoir volume “V min” and an area “A” can be greater than 100 mm. In other words, the reservoir 138 defines a reservoir volume “V”, and the second set of apertures 126 define the area “A” such that the minimum reservoir volume “V min” to the area “A” ratio is greater than or equal to 100 mm to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow. It is also contemplated that the ratio ranges between 100 mm and 2000 mm. In the illustrated FIG. 3, the reservoir volume “V” is shown to be equal to minimum reservoir volume “V min”.

However, some of the diverted flow “D” can still travel forward in the reservoir 138 without changing direction of travel to flow out to the environment via the first set of apertures 118. In other words, the exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 further defines a secondary exhaust gas flow path “S”. The exhaust gases following the secondary exhaust gas flow path “S” exit the exhaust pipe 120 as diverted flow “D” via the second set of apertures 126 then flow through the reservoir 138, and then flow out to the environment via the first set of apertures 118. The secondary exhaust gas flow path “S” can be linear or non-linear. The proportion of the diverted flow “D” following the secondary exhaust gas flow path “S” is substantially lower than the proportion of the diverted flow “D” that is sucked back into the exhaust pipe 120. In some embodiments, the at least one divider 130 has a fourth set of apertures (not shown) configured to allow fluid communication between at least two chambers 134, 136. In other words, the fourth set of apertures can allow some proportion of the diverted flow “D” to travel through the fourth set of apertures and reach the second chamber 136. This alternate flow path can be configured to allow the to-and-fro flow of some proportion of the diverted flow “D” between the first chamber 134 and the second chamber 136.

With continuous reference to FIG. 3, the second chamber 136 is preferably filled with absorption material and is configured to attenuate high frequency air rush, in particular ranging from 500-2500 Hz. In other words, the second chamber 136 is the roving chamber such that the second chamber 136 is disposed downstream of the reservoir 138 and on an opposite side of the divider 130 separating the roving chamber and the reservoir 138. Further, the second chamber 136 is fluidly associated with the primary exhaust gas flow path “P” via the third set of apertures 128. In other words, the third set of apertures 128 is a row of apertures 128 at least partially surrounded by the absorption material in the second chamber 136. The exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the second chamber 136 to contact the absorption material filled in the second chamber 136 and/or flow back into the exhaust pipe 120 from the second chamber 136 through the third set of apertures 128 to allow noise attenuation.

FIG. 4 illustrates a perspective view of the exhaust muffler 110 of the vehicle exhaust system 100 according to a second embodiment of the present invention. The exhaust muffler 110 includes the hollow body 112, which is preferably the cylindrical body made from any non-corrosive and durable material e.g. stainless steel. The hollow body 112 further includes end plates 111, 113. Further, the hollow body 112 defines the first set of apertures 118 on the hollow body 112. The first set of apertures 118 is a row of the apertures 118 disposed at a predefined area along the circumference of the hollow body 112. In some embodiments, the first set of apertures 118 is one or more than one row of apertures 118 disposed at a predefined area along the circumference of the hollow body 112, or along the entire circumference of the hollow body 112 or at predefined intervals along the circumference of the hollow body 112. Further, the first set of apertures 118 have shape similar to a slot, in particular to a substantially elliptical slot.

Further, the hollow body 112 includes the exhaust pipe 120. The exhaust pipe 120 includes the inlet opening 114, and the outlet opening 116 spaced apart from the inlet opening 114. The inlet opening 114 and the outlet opening 116 of the hollow body 112 have preferably the circular or oval or trioval cross-section, preferably with the parallel orientation relative to each other. Further, the exhaust pipe 120 is disposed at least partially within the hollow body 112. The exhaust pipe 120 is adapted to allow the flow of exhaust gases therethrough. The exhaust pipe 120 can have length smaller, larger, or equal to the hollow body 112. The exhaust pipe 120 can have a shape similar or dissimilar to the hollow body 112. The exhaust pipe 120 can be made from a material similar or dissimilar to the material of the hollow body 112.

Further, the hollow body 112 includes at least one divider 130. The at least one divider 130 is fixedly or removably coupled to the hollow body 112 in any known manner in the related art. The at least one divider 130 defines the opening 132 to allow the exhaust pipe 120 to pass therethrough and further to support the exhaust pipe 120 in the hollow body 112. In other words, the at least one divider 130 is connected with the exhaust pipe 120 to allow the exhaust pipe 120 to pass therethrough.

Further, the at least one divider 130 divides the hollow body 112 into at least the first chamber 134 and the second chamber 136 operatively configured for sound attenuation. The first chamber 134 is configured to be engaged with the second chamber 136. The second chamber 136 is disposed downstream of the first chamber 134 and on the opposite side of the divider 130 separating the second chamber 136 and the first chamber 134. The first chamber 134 and the second chamber 136 are respectively defined by the volume between the exhaust pipe 120 and the hollow body 112 on opposite sides of the divider 130. The first chamber 134 and the second chamber 136 can have equal or unequal volumes as per requirement. As exemplary illustrated in FIG. 4, the second chamber 136 has more volume than the first chamber 134.

Further, the exhaust pipe 120 defines the second set of apertures 126 (as shown in FIG. 5) and the third set of apertures 128 on the exhaust pipe 120 such that the exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the hollow body 112 and/or flow back into the exhaust pipe 120 from the hollow body 112 through the second set of apertures 126 and the third set of apertures 128. In other words, the exhaust gases flowing through the exhaust pipe 120 fluidly associate or communicate with the first chamber 134 and the second chamber 136 via the second set of apertures 126 and the third set of apertures 128 respectively. Further, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 have apertures of shape similar to a slot. However, in some embodiments, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 can have apertures of circular, oval, triangular, square, rectangular, elliptical, or any other shape as per requirement. Further, in some embodiments, the second set of apertures 126, and/or the third set of apertures 128, and/or first set of apertures 118 can have different shapes, and sizes as per requirement.

FIG. 5 illustrates a cross-sectional view of the exhaust muffler 110 of the vehicle exhaust system 100 according to the second embodiment of the present invention. The exhaust muffler 110 includes the hollow body 112, which defines the first set of apertures 118 on the hollow body 112 proximal to the first chamber 134. Further, the hollow body 112 includes the exhaust pipe 120 having the inlet opening 114, and the outlet opening 116 spaced apart from the inlet opening 114. The exhaust pipe 120 is disposed at least partially within the hollow body 112. The exhaust pipe 120 defines the second set of apertures 126 and the third set of apertures 128 on the exhaust pipe 120 proximal to the first chamber 134 and the second chamber 136 respectively.

Further, the second set of apertures 126 is the row of the apertures 126 disposed at the predefined area along the circumference of the exhaust pipe 120. The second set of apertures 126 are disposed substantially opposite to the first set or apertures 118 along the circumference of the exhaust pipe 120. In some embodiments, the second set of apertures 126 is one or more than one row of apertures 126 disposed at a predefined area along the circumference of the exhaust pipe 120, or along the entire circumference of the exhaust pipe 120 or at predefined intervals along the circumference of the exhaust pipe 120. Further, the third set of apertures 128 is one or more rows of the apertures 128 disposed along the circumference of the exhaust pipe 120 proximal to the second chamber 136, preferably at predefined intervals along the exhaust pipe 120.

Further, the exhaust pipe 120 is adapted to allow the flow of exhaust gases therethrough. The exhaust pipe 120 has the inner surface 122 and the outer surface 124 disposed opposite to the inner surface 122 such that the second set of apertures 126 and the third set of apertures 128 extend from the inner surface 122 to the outer surface 124 respectively.

Further, the inner surface 122 defines the primary exhaust gas flow path “P” extending along from the inlet opening 114 of the exhaust pipe 120 to the outlet opening 116 of the exhaust pipe 120. The exhaust gases received from the exhaust components 104 travel through the primary exhaust gas flow path “P” in the linear or non-linear manner. Further, the first chamber 134 defines the reservoir 138 fluidly associated with the primary exhaust gas flow path “P” via the second set of apertures 126, and to the environment via the first set of apertures 118. A portion of the exhaust gases travelling through the primary exhaust gas flow path “P” escapes the exhaust pipe 120 via the second set of apertures 126 to enter into the reservoir 138 and break the standing waves.

The exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 defines the diverted flow “D” and the reservoir 138 holds the diverted flow “D” within the reservoir 138. The exhaust gases can travel perpendicular or parallel or at any other orientation relative to the primary exhaust gas flow path “P” and through the second set of apertures 126 to define the diverted flow “D”. The reservoir 138 enables the diverted flow “D” to change direction at least once within the reservoir 138. In other words, the diverted flow “D” flows through the reservoir 138 in a first direction “F1” and a second direction “F2” opposite to the first direction “F1”. The first direction “F1” and the second direction “F2” can be parallel, orthogonal, or be at any other orientation relative to the exhaust pipe 120. Preferably, the first direction “F1” is a clockwise direction relative to the inlet 114 and the second direction “F2” is an anticlockwise direction relative to the inlet 114. In other words, some of the diverted flow “D” is drawn back into the exhaust pipe 120 with the suction flow, to ensure that little to none of the diverted flow “D” becomes a leaked mass flow. However, in order to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow, a ratio between a minimum reservoir volume “V min” and an area “A” can be greater than 100 mm. In other words, the reservoir 138 defines a reservoir volume “V”, and the second set of apertures 126 define the area “A” such that the minimum reservoir volume “V min” to the area “A” ratio is greater than or equal to 100 mm to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow. It is also contemplated that the ratio ranges between 100 mm and 2000 mm. In the illustrated FIG. 5, the reservoir volume “V” is shown to be equal to minimum reservoir volume “V min”.

However, some of the diverted flow “D” can still travel forward in the reservoir 138 without changing direction of travel to flow out to the environment via the first set of apertures 118. In other words, the exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 further defines the secondary exhaust gas flow path “S”. The exhaust gases following the secondary exhaust gas flow path “S” exit the exhaust pipe 120 as diverted flow “D” via the second set of apertures 126 then flow through the reservoir 138, and then flow out to the environment via the first set of apertures 118. The secondary exhaust gas flow path “S” can be linear or non-linear. The proportion of the diverted flow “D” following the secondary exhaust gas flow path “S” is substantially lower than the proportion of the diverted flow “D” that is sucked back into the exhaust pipe 120.

In some embodiments, the end plate 111 of the hollow body 112 can have a set of fifth apertures (not shown) to allow connection of the reservoir 138 with the external environment. In some embodiments, the at least one divider 130 has the fourth set of apertures (not shown) configured to allow fluid communication between the first chamber 134 with second chamber 136 and further with the environment via a sixth set of apertures (not shown) provided with the end plate 113.

With continuous reference to FIG. 5, the second chamber 136 is preferably filled with absorption material (not shown) and is configured to attenuate high frequency air rush, in particular ranging from 500-2500 Hz. In other words, the second chamber 136 is the roving chamber such that the second chamber 136 is disposed downstream of the reservoir 138 and on an opposite side of the divider 130 separating the roving chamber and the reservoir 138. Further, the second chamber 136 is fluidly associated with the primary exhaust gas flow path “P” via the third set of apertures 128. In other words, the third set of apertures 128 is the row of apertures 128 at least partially surrounded by the absorption material in the second chamber 136. The exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the second chamber 136 to contact the absorption material filled in the second chamber 136 and/or flow back into the exhaust pipe 120 from the second chamber 136 through the third set of apertures 128 to allow noise attenuation.

FIG. 6 illustrates a cross-sectional view of the exhaust muffler 110 of the vehicle exhaust system 100 according to a third embodiment of the present invention. The exhaust muffler 110 includes a hollow body 112′, which is preferably and substantially a two-part cylindrical body. In other words, the hollow body 112′ includes a first part 112A and a second part 112B connected to the first part 112A preferably in a toolless manner and without using an external component. For example, the first part 112A of the hollow body 112′ can be form-fitted or friction fitted with the second part 112B. In particular, during the connection of the first part 112A and the second part 112B, the first part 112A at least partially overlaps upon the second part 112B. Further, the second part 112B includes two oppositely disposed nose sections, or the sections with reduced cross-section areas compared to the remaining portion of the second part 112B. The nose sections of the second part 112B are formed on both sides of the second part 112B.

Further, the hollow body 112′ includes the exhaust pipe 120. The exhaust pipe 120 includes the inlet opening 114, and the outlet opening 116 spaced apart from the inlet opening 114. Further, the exhaust pipe 120 is disposed at least partially within the hollow body 112′. The exhaust pipe 120 is adapted to allow a flow of exhaust gases therethrough. Further, the exhaust pipe 120 is held in the hollow body 112′ using the nose sections of the second part 112B as well as due to the structure of the first part 112A.

Further, the hollow body 112′ defines the first set of apertures 118 on the hollow body 112′, in particular the first part 112A of the hollow body 112′. The first set of apertures 118 according to this embodiment is similar in function to that in previous embodiments and may further have any design or arrangement variations as discussed in any of the previous embodiments. Further, the exhaust pipe 120 defines the second set of apertures 126 (as with previous embodiments) and the third set of apertures 128 (as with previous embodiments) on the exhaust pipe 120 such that the exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the hollow body 112′ and/or flow back into the exhaust pipe 120 from the hollow body 112′ through the second set of apertures 126 and the third set of apertures 128.

Further, the hollow body 112′ includes the first chamber 134 and the second chamber 136 such that the first chamber 134 is formed between the first part 112A and the exhaust pipe 120 whereas the second chamber 136 is formed between the second part 112B and the exhaust pipe 120. The first chamber 134 and the second chamber 136 in this embodiment are advantageously separated by one of the nose section of the second part 112B, such that the nose section of the second part 112B faces the first part 112A and also at least partially engages with the first part 112A during the assembly of the first part 112A and the second part 112B to form the hollow body 112′. Further, the first chamber 134 is configured to be fluidly engaged with the second chamber 136. The second chamber 136 is disposed downstream of the first chamber 134.

Further, with continuous reference to FIG. 6, the exhaust pipe 120 has the inner surface 122 and the outer surface 124 disposed opposite to the inner surface 122 such that the second set of apertures 126 and the third set of apertures 128 extend from the inner surface 122 to the outer surface 124 respectively. Further, the inner surface 122 defines the primary exhaust gas flow path “P” extending along from the inlet opening 114 of the exhaust pipe 120 to the outlet opening 116 of the exhaust pipe 120. The exhaust gases received from the exhaust components 104 travel through the primary exhaust gas flow path “P” in the linear or non-linear manner. Further, the first chamber 134 defines the reservoir 138 fluidly associated with the primary exhaust gas flow path “P” via the second set of apertures 126, and to the environment via the first set of apertures 118. A portion of the exhaust gases travelling through the primary exhaust gas flow path “P” escapes the exhaust pipe 120 via the second set of apertures 126 to enter into the reservoir 138 and break the standing waves.

The exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 defines the diverted flow “D” or the positive pulse and the reservoir 138 holds the diverted flow “D” within the reservoir 138. The exhaust gases can travel perpendicular or parallel or at any other orientation relative to the primary exhaust gas flow path “P” and through the second set of apertures 126 to define the diverted flow “D”. The reservoir 138 enables the diverted flow “D” to change direction at least once within the reservoir 138. In other words, the diverted flow “D” flows through the reservoir 138 in a first direction “F1” and a second direction “F2” opposite to the first direction “F1”. The first direction “F1” and the second direction “F2” can be parallel, orthogonal, or be at any other orientation relative to the exhaust pipe 120. Preferably, the first direction “F1” is a clockwise direction relative to the inlet 114 and the second direction “F2” is an anticlockwise direction relative to the inlet 114. In other words, some of the diverted flow “D” is drawn back into the exhaust pipe 120 with the suction flow or the negative pulse, to ensure that little to none of the diverted flow “D” becomes a leaked mass flow.

However, in order to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow, a ratio between a minimum reservoir volume “V min” and an area “A” can be greater than 100 mm. In other words, the reservoir 138 defines a reservoir volume “V”, and the second set of apertures 126 define the area “A” such that the minimum reservoir volume “V min” to the area “A” ratio is greater than or equal to 100 mm to enable any exhaust gas drawn out along the diverted flow “D” are drawn back into the exhaust pipe 120 via the suction flow. It is also contemplated that the ratio ranges between 100 mm and 2000 mm. In the illustrated FIG. 6, the reservoir volume “V” is shown to be equal to minimum reservoir volume “V min”.

However, some of the diverted flow “D” can still travel forward in the reservoir 138 without changing direction of travel to flow out to the environment via the first set of apertures 118. In other words, the exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 further defines the secondary exhaust gas flow path “S”. The exhaust gases following the secondary exhaust gas flow path “S” exit the exhaust pipe 120 as diverted flow “D” via the second set of apertures 126 then flow through the reservoir 138, and then flow out to the environment via the first set of apertures 118.

With continuous reference to FIG. 6, the second chamber 136 is preferably filled with absorption material (not shown) and is configured to attenuate high frequency air rush, in particular ranging from 500-2500 Hz. In other words, the second chamber 136 is the roving chamber such that the second chamber 136 is disposed downstream of the reservoir 138 and on an opposite side of the divider 130 separating the roving chamber and the reservoir 138. Further, the second chamber 136 is fluidly associated with the primary exhaust gas flow path “P” via the third set of apertures 128. In other words, the third set of apertures 128 is the row of apertures 128 at least partially surrounded by the absorption material in the second chamber 136. The exhaust gases flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the second chamber 136 to contact the absorption material filled in the second chamber 136 and/or flow back into the exhaust pipe 120 from the second chamber 136 through the third set of apertures 128 to allow noise attenuation.

FIG. 7 illustrates a schematic view representation the exhaust muffler 110 of the vehicle exhaust system 100 according to a fourth embodiment of the present invention. The exhaust muffler 110 includes the hollow body 112″, which is preferably a cylindrical body. The hollow body 112″ includes an inlet 107 and an outlet 109 such that inlet 107 is substantially orthogonal to the outlet 109. The inlet 107 is configured to allow the ingress of the exhaust gases received from the exhaust components 104 into the hollow body 112″. Further, the hollow body 112″ includes the end plates 111, 113, with the end plate 111 having an opening, which is also the outlet 109 of the hollow body 112″.

The exhaust muffler 110 further includes the exhaust pipe 120. The exhaust pipe 120 includes the outlet opening 116, with the inlet opening 114 on the other end of the exhaust pipe 120 being closed in this embodiment. The exhaust pipe 120 defines the second set of apertures 126 (as with previous embodiments but not shown) and the third set of apertures 128 (as with previous embodiments but not shown) on the exhaust pipe 120. The exhaust pipe 120 is disposed at least partially within the hollow body 112″ such that some portion of the exhaust pipe 120 extends beyond the end plates 111, 113, in particular the end plate 111 via the outlet 109. Further, the hollow body 112″ includes at least one divider 130. The at least one divider 130 is fixedly or removably coupled to the hollow body 112″ in any known manner in the related art. The at least one divider 130 defines the opening 132 to allow the exhaust pipe 120 to pass therethrough and further to support the exhaust pipe 120 in the hollow body 112″. In other words, the at least one divider 130 is connected with the exhaust pipe 120 to allow the exhaust pipe 120 to pass therethrough.

Further, the at least one divider 130 divides the hollow body 112″ into at least a third chamber 140 and the second chamber 136. In this embodiment, the third chamber 140 and the second chamber 136 can be acoustic chambers, or non-acoustic chambers, or a combination of both. The second chamber 136 is disposed upstream of the third chamber 140 and on an opposite side of the divider 130 separating the second chamber 136 and the third chamber 140. The third chamber 140 and the second chamber 136 can have equal or unequal volumes as per requirement. Further, the exhaust muffler 110 includes a first chamber 134′. The first chamber 134′ is disposed outside the hollow body 112″ and has the diameter lesser than the diameter of the second chamber 136 and the third chamber 140. The end cap 111 can have mechanical features to connect with or support the first chamber 134′. The first chamber 134′ is formed by a hood surrounding the part of the exhaust pipe 120 extending beyond the end cap 111. The hood have a seventh set of apertures (not shown) along the periphery of the hood to establish fluid communication between the first chamber 134′ and the environment.

Further, when the exhaust gases enter the hollow body 112″ via the inlet 107, the exhaust gases flow within the second chamber 136 and head towards and into the exhaust pipe 120 via the third set of apertures 128. Further, the exhaust gases now flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the hollow body 112″ and the first chamber 134′ and/or flow back into the exhaust pipe 120 from the hollow body 112″ and the first chamber 134′ through the third set of apertures 128 and the second set of apertures 126 respectively.

Further, the exhaust pipe 120 has the inner surface 122 and the outer surface 124 disposed opposite to the inner surface 122 such that the second set of apertures 126 and the third set of apertures 128 extend from the inner surface 122 to the outer surface 124 respectively. Further, the inner surface 122 defines the primary exhaust gas flow path “P” extending along the exhaust pipe 120. The exhaust gases received via the inlet 107 travel through the primary exhaust gas flow path “P” in the linear or non-linear manner. Further, the first chamber 134′ defines the reservoir 138′ fluidly associated with the primary exhaust gas flow path “P” via the second set of apertures 126, and to the environment via the seventh set of apertures (not shown). A portion of the exhaust gases travelling through the primary exhaust gas flow path “P” escapes the exhaust pipe 120 via the second set of apertures 126 to enter into the reservoir 138′ and break the standing waves.

The exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 defines the diverted flow “D” or the positive pulse of the exhaust gases and the reservoir 138′ holds the diverted flow “D” within the reservoir 138′. The exhaust gases can travel perpendicular or parallel or at any other orientation relative to the primary exhaust gas flow path “P” and through the second set of apertures 126 to define the diverted flow “D”. The reservoir 138′ enables the diverted flow “D” to change direction at least once within the reservoir 138′. In other words, the diverted flow “D” flows through the reservoir 138′ in a first direction “F1” and a second direction “F2” opposite to the first direction “F1”. The first direction “F1” and the second direction “F2” can be parallel, orthogonal, or be at any other orientation relative to the exhaust pipe 120. In other words, some of the diverted flow “D” is drawn back into the exhaust pipe 120 with the suction flow or the negative pulse, to ensure that little to none of the diverted flow “D” becomes a leaked mass flow. Further, the reservoir 138′ can be designed in a manner such that it is able to hold the diverted flow “D” or the positive pulse of the exhaust gases, but at the same time, it should be able to prevent the fresh air from the environment entering into the exhaust pipe 120 with the suction flow. The fresh air flow path “FA” is illustrated in FIG. 7.

Further, some of the diverted flow “D” can still travel forward in the reservoir 138′ without changing direction of travel to flow out to the environment via the seventh set of apertures. In other words, the exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 further defines the secondary exhaust gas flow path “S”. The exhaust gases following the secondary exhaust gas flow path “S” exit the exhaust pipe 120 as diverted flow “D” via the second set of apertures 126 and then flow through the reservoir 138′, and then flow out to the environment via the seventh set of apertures.

FIG. 8 illustrates a schematic representation of the exhaust muffler 110 of the vehicle exhaust system 100 according to a fifth embodiment of the present invention. The exhaust muffler 110 includes the hollow body 112′″, which is preferably a cylindrical body. The hollow body 112″′ includes the inlet 107 and the outlet 109 such that inlet 107 is substantially orthogonal to the outlet 109. The inlet 107 is configured to allow the ingress of the exhaust gases received from the exhaust components 104 into the hollow body 112″′. Further, the hollow body 112″′ includes the end plates 111, 113, with the end plate 111 having the opening, which is also the outlet 109 of the hollow body 112′″.

The exhaust muffler 110 further includes the exhaust pipe 120. The exhaust pipe 120 includes the outlet opening 116, with the inlet opening 114 on the other end of the exhaust pipe 120 being closed in this embodiment. The exhaust pipe 120 defines the second set of apertures 126 (as with previous embodiments but not shown) and the third set of apertures 128 (as with previous embodiments but not shown) on the exhaust pipe 120. The exhaust pipe 120 is disposed at least partially within the hollow body 112′″ such that some portion of the exhaust pipe 120 extends beyond the end plates 111, 113, in particular the end plate 111 via the outlet 109. Further, the hollow body 112″′ includes at least one divider 130. The at least one divider 130 is fixedly or removably coupled to the hollow body 112′″ in any known manner in the related art. The at least one divider 130 defines the opening 132 to allow a secondary pipe 142 to pass therethrough and further support the secondary pipe 142 within the hollow body 112″′. The secondary pipe 142 has greater diameter than the exhaust pipe 120. In other words, the exhaust pipe 120 and the secondary pipe 142 are concentrically disposed within the hollow body 112“ ” with the exhaust pipe 120 supported by an end cap 131 of the secondary pipe 142. In other words, the secondary pipe 142 has a closed end closed by the end cap 131 and an open-end opposite to the closed end. The end cap 131 includes an opening 133 to allow the exhaust pipe 120 to pass therethrough within the hollow body 112′″ and further to support the exhaust pipe 120.

Further, the at least one divider 130 divides the hollow body 112′″ into at least a fourth chamber 144 and the second chamber 136. In this embodiment, the fourth chamber 144 and the second chamber 136 can be acoustic chambers, or non-acoustic chambers, or a combination of both. The second chamber 136 is disposed upstream of the fourth chamber 144 and on an opposite side of the divider 130 separating the second chamber 136 and the fourth chamber 144. Further, the exhaust muffler 110 includes a first chamber 134″ defined by the volume between the exhaust pipe 120 and the secondary pipe 142. The first chamber 134″ has the diameter lesser than the diameter of the second chamber 136 and the fourth chamber 144. The first chamber 134″ defines the reservoir 138″ having the fluid connection with the exhaust pipe 120 via the second set of apertures 126 and with the environment via the open end of the secondary pipe 142.

Further, when the exhaust gases enter the hollow body 112′″ via the inlet 107, the exhaust gases flow within the second chamber 136 and head towards and into the exhaust pipe 120 via the third set of apertures 128. Further, the exhaust gases now flowing through the exhaust pipe 120 flow out of the exhaust pipe 120 within the hollow body 112″′ and the first chamber 134″ and/or flow back into the exhaust pipe 120 from the hollow body 112″′ and the first chamber 134″ through the third set of apertures 128 and the second set of apertures 126 respectively.

Further, the exhaust pipe 120 has the inner surface 122 and the outer surface 124 disposed opposite to the inner surface 122 such that the second set of apertures 126 and the third set of apertures 128 extend from the inner surface 122 to the outer surface 124 respectively. Further, the inner surface 122 defines the primary exhaust gas flow path “P” extending along the exhaust pipe 120. The exhaust gases received via the inlet 107 travel through the primary exhaust gas flow path “P” in the linear or non-linear manner. Further, the first chamber 134″ defining the reservoir 138″ is fluidly associated with the primary exhaust gas flow path “P” via the second set of apertures 126, and to the environment via the open end of the secondary pipe 142. A portion of the exhaust gases travelling through the primary exhaust gas flow path “P” escapes the exhaust pipe 120 via the second set of apertures 126 to enter into the reservoir 138″ and break the standing waves.

The exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 defines the diverted flow “D” or the positive pulse of the exhaust gases and the reservoir 138″ holds the diverted flow “D” within the reservoir 138″. The exhaust gases can travel perpendicular or parallel or at any other orientation relative to the primary exhaust gas flow path “P” and through the second set of apertures 126 to define the diverted flow “D”. The reservoir 138″ enables the diverted flow “D” to change direction at least once within the reservoir 138″. In other words, the diverted flow “D” flows through the reservoir 138″ in a first direction “F1” and a second direction “F2” opposite to the first direction “F1”. The first direction “F1” and the second direction “F2” can be parallel, orthogonal, or be at any other orientation relative to the exhaust pipe 120. In other words, some of the diverted flow “D” is drawn back into the exhaust pipe 120 with the suction flow or the negative pulse, to ensure that little to none of the diverted flow “D” becomes a leaked mass flow. Further, the reservoir 138″ can be designed in a manner such that it is able to hold the diverted flow “D” or the positive pulse of the exhaust gases, but at the same time, it should be able to prevent the fresh air from the environment entering into the exhaust pipe 120 with the suction flow. The fresh air flow path “FA” is illustrated in FIG. 8.

Further, some of the diverted flow “D” can still travel forward in the reservoir 138″ without changing direction of travel to flow out to the environment via the open end of the secondary pipe 142. In other words, the exhaust gases traveling through the primary exhaust gas flow path “P” and through the second set of apertures 126 further defines the secondary exhaust gas flow path “S”. The exhaust gases following the secondary exhaust gas flow path “S” exit the exhaust pipe 120 as diverted flow “D” via the second set of apertures 126 then flow through the reservoir 138″, and then flow out to the environment via the open end of the secondary pipe 142.

While various embodiments are described and shown with the exhaust pipe 120 having a single inlet opening 114 and a single outlet opening 116, the exhaust pipe 120 can have a dual outlet configuration with two outlet openings 116 or two inlet openings 114. Multiple inlet or multiple outlet openings can include the exhaust pipe 120 being Y-shaped or T-shaped. In such dual outlet configurations, a single first chamber can be upstream of the dual outlets (e.g., at the exhaust split or upstream of the exhaust pipe splitting to the two outlet openings 116), such as generally illustrated in connection with the first chamber 134 in FIGS. 3-6, Alternatively a first chamber can be positioned upstream of each of the dual outlet openings, such as generally illustrated in connection with the first chambers 134′, 134″ in FIGS. 7 and 8, respectively.

While aspects of the present invention have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments can be contemplated by the modification of the disclosed machines, systems, and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present invention as determined based upon the claims and any equivalents thereof.