Abstract: An air blower has an inlet muffler and an outlet muffler to reduce the noise of the air blower during operation. Each of the mufflers may have two sections. One section is configured to attenuate high frequency noise and the other section is configured to attenuate lower frequency noise. A tubular internal wall in each of the mufflers defines the through passage for each of the mufflers. A noise absorbent material may be fitted about the tubular wall within each muffler. A plurality of holes are formed along the tubular wall of each through passage to expose the through passage to the noise absorbent material. A heater plenum may be interposed between the blower plenum and the outlet muffler to heat the air from the blower plenum. A filter at the input muffler filters the air sucked into the air blower.

Abstract: An exhaust device (108) for a vehicle is provided. The exhaust device (108) includes an outer shell (202), an inlet (206) to receive exhaust gases, an outlet (208), an inner shell (204) received within the outer shell (202), a pair of partition walls (216) and a Helmholtz neck (220). The inner shell (204) defines an inner volume (210). A plurality of first circumferential openings (212) extending through the inner shell (204) fluidly communicates the inlet (206) with the inner volume (210). A plurality of second circumferential openings (214) extending through the inner shell (204) fluidly communicates the outlet (208) with the inner volume (210). The pair of partition walls (216) is disposed between the inner shell (204) and the outer shell (202). The pair of partition walls (216), the inner shell (204) and the outer shell (202) define a Helmholtz chamber (218) therebetween. The partition walls (216) seal the Helmholtz chamber (218) from the inlet (206) and the outlet (208).

Abstract: Provided is a refrigeration machine provided with: a refrigeration cycle having a compressor, a condenser, an expander, an evaporator, and piping (12) which sequentially connects the compressor, the condenser, and the expander; and an acoustic device (13) having a space formation section (14) which has one end (14a) connected to the piping (12) and in which a space is formed, the acoustic device (13) also having a vibration body (20) which is affixed integrally to the other end of the space formation section (14) and which has a lower natural frequency than the space formation section (14).

Abstract: A supercharger assembly comprises a housing, a rotor bore with an outer wall, an outlet in an outlet plane, an inlet in an inlet plane perpendicular to the outlet plane, and an outlet divider wall. The supercharger assembly comprises a first recess, a first perforated material covering the first recess, and an outlet resonator. The first recess is separated from the outlet by the outlet divider wall. The first recess is located between the outer wall and the first perforated material.

Abstract: An exhaust system component includes a pipe having a pipe wall with an inner surface defining an exhaust gas passage and with an outer surface and a louver bridge portion formed in the pipe wall. The louver bridge portion has bridge ends transitioning from adjacent pipe wall portions to a bridge raised portion with raised side edges detached from adjacent opening side edges of the pipe wall. Each bridge side edge is radially outward of the adjacent opening side edge of the pipe wall to define a louver opening at each of two opposite sides of the louver bridge portion. Fluid communication through the two louvered openings, between the exhaust gas passage and an exterior of the component, attenuates resonant frequencies generated during operation of an exhaust system to which the exhaust system component is connected.

Abstract: There is provided a muffler structure of a saddle-type vehicle. The muffler structure is disposed at a downstream side of an exhaust pipe extending from an exhaust port of a cylinder head. A pipe is connected to the exhaust pipe and inserted into a muffler main body. The pipe is provided with an expansion chamber having an inner diameter that is larger than an inner diameter of the exhaust pipe. At least a part of the expansion chamber is disposed in the muffler main body, and a plurality of through holes are formed on an outer peripheral surface of the expansion chamber disposed in the muffler main body.

Abstract: A resonator divides and forms a sound attenuation space and maintains airtightness without external force. The resonator includes a tubular cover body and having a hollow portion with different diameters, a tubular insert inserted into the cover body and having second hollow portion that turbocharger air is introduced into the second hollow portion, the air being guided into the first hollow portion on an outer surface of the insert body; and one or more space partition members coupled to the outer surface of the insert body to form airtight noise attenuation spaces. The partition members are ring shaped, and each space partition member is formed of a resilient material, and each space partition member has a contact portion formed by an inclined surface to be in contact with the inner surface of the cover body in a direction in which the insert body is inserted into the cover body.

Abstract: An arrangement (10) in a wheel well (2) of a vehicle (1), comprising at least one passage (11) providing fluid communication between an engine compartment (3) and the wheel well to permit airflow there through, wherein the passage is non-straight in order to prevent ingress of water into the engine compartment. Also disclosed is a vehicle comprising such an arrangement.

Abstract: A combustor is provided with a combustion liner (12) in which a combustion gas flows through the inner peripheral side and a plurality of through-holes (14) are formed, and a sound attenuator (20) having a space-forming member (21) configured to form a space (S) connected to the plurality of through-holes (14) at the outer peripheral side of the combustion liner (12). A method of repairing a combustor involves executing: an opening step of opening a portion of the space-forming member (21) in contact with the outside and bringing the outside and the space (S) in communication with each other; a cylinder repair step of repairing the combustion liner (12); a foreign substance removal step of removing foreign substances in the space (S) from the opening (23) opened in the opening step to the outside, after the cylinder repair step; and a closing step of closing the opening (23) using a lid (24), after the foreign substance removal step.

Abstract: A variable noise attenuation element includes at least two tube sections that define an overall tube length that defines a first effective length and associated first peak frequency for noise attenuation, and a valve having a valve member. The valve joins the tube sections together and includes openings that permit communication between the tube sections when the valve is in an open configuration. The valve member operates to close the opening in response to a predetermined vacuum level within the tube sections to define a second tube effective length and associated second peak frequency for attenuation that is less than the overall length. A method of attenuating noise in a vehicle using a passive attenuation arrangement operates a valve disposed between two tube sections to change an effective length of the tube and associated peak frequencies for attenuation in response to an engine operating parameter.

Abstract: An exhaust system for internal combustion engines has an exhaust tract, which has at least one first flow path and a second flow path for an exhaust gas stream. The first and the second flow path extend fluidically separated from each other from a pre-silencer to at least one end silencer. Depending on the rotational speed of the engine, the first flow path can be continuously closed by way of a controllable flap, wherein the exhaust gas stream is guided through the second flow path when the flap is closed.

Abstract: A reactive muffler having multiple structures tuned to multiple frequency ranges or characteristics, and thus providing attenuation over a band of frequencies broader than a conventional reactive muffler. The present invention provides such a muffler by providing structures internal to the muffler skin that define multiple different volumes/cavities, each of which is tuned to provide distinctly different attenuation characteristics. In effect, the inventive muffler acts as multiple distinctly different mufflers providing distinctly different noise attenuation, though packaged within a single muffler skin/body.

Abstract: An intake sound introducing apparatus has, for example, a branch pipe, a sound creator, a communication pipe, and a resonator. The branch pipe branches from an intake pipe of the engine. The sound creator includes a vibrator that vibrates with the intake pulsation of the intake sound propagating within the branch pipe. The communication pipe provides communication between the inside of a casing of the sound creator and the inside of the cabin. The resonator is provided in the communication pipe.

Abstract: A muffler (1) for an exhaust system of an internal combustion engine has a housing (2) with an expansion chamber (6). An inlet pipe (7) extends into the housing (2) and has an end section (8) with an outlet opening (9) to the expansion chamber (6). A main outlet pipe (10) has an initial section (11) protruding into the end section (8) of the inlet pipe (7). A secondary outlet pipe (15) has an inlet opening (16) in the expansion chamber (6). A gap (14) in an overlapping area (13) between the end section (8) and the initial section (11) forms a bypass in the end section (8) of the inlet pipe (7), which bypasses the initial section (11) of the main outlet pipe (10). Through the bypass gap (14), exhaust gas flows from the inlet pipe (7) into the expansion chamber (6) and out the secondary outlet pipe (15).

Abstract: Fluid attenuator systems and methods for attenuating fluid ripple waves within a main fluid line (e.g., a main hydraulic fluid line of an aircraft hydraulic system). At least one attenuator branch conduit may be provided in fluid communication with and at substantially a right angle to the main fluid line with a porous material positioned therewithin (e.g., at an open inlet or a closed distal end of the at least one attenuator branch conduit). The porous material may be a metallic or ceramic open-cell foam material. Multiple attenuator branch conduits may be provided with each having a different length as compared to the others. In such embodiments, the porous material may (or may not) be positioned within the different length attenuator branch conduits (e.g., at an open inlet or a closed distal end of respective ones of attenuator branch conduits).

Abstract: A wide-band damper is designed for charge air lines of an internal combustion engine with turbocharger. The wide-band damper has an inlet and an outlet. Proceeding from the inlet, at least three slot chambers are arranged axially in series. The slot chambers are dimensioned for different frequencies f1, f2 and f3. At least three gap chambers are provided, which are arranged axially in series and axially downstream of the at least three slot chambers. The gap chambers are dimensioned for different frequencies f6, f7 and f8. Each of the frequencies f1, f2 and f3 of the slot chambers is lower than each of the frequencies f6, f7 and f8 of the gap chambers.

Abstract: A modal attenuator may include an attenuator body having a lead-in segment and a lead-out segment joined by a connection segment, a perforated screen disposed within the attenuator body and spaced apart from the attenuator body to form an annular space, and a plurality of rings disposed between the perforated screen and the attenuator body. When fluid flows through the modal attenuator, sound waves pass through the perforated screen and are reflected back by the plurality of rings to disrupt other sound waves, thereby reducing fluid noise in the modal attenuator.

Abstract: Based on sound measured in the interior of an exhaust system components of an ideal control signal are calculated, the components comprising sine wave oscillations comprising amplitudes phase-shifted by 90° relative to each other. From the amplitudes, an overall amplitude is calculated. If the overall amplitude is greater than a reference amplitude, calculating a correction factor from the reference amplitude and the overall amplitude, weighting the amplitudes with the correction factor to obtain weighted amplitudes, and forming the sum of the products of the weighted amplitudes with the associated sine wave oscillations and outputting the sum as control signal to a loudspeaker, follows. Otherwise, if the overall amplitude is smaller or equal to the reference amplitude, forming the sum of the products of the amplitudes of the ideal control signal with the associated sine wave oscillations and outputting the sum as control signal to the loudspeaker, follows.

Abstract: A variable frequency Helmholtz resonant cavity includes a Helmholtz resonant cavity body, two Helmholtz resonant cavity pipes with different cross-sectional areas and lengths and a control valve plate. The Helmholtz resonant cavity body is connected with the main pipe of the intake system via the Helmholtz resonant cavity pipes, and the control valve plate is disposed at the location where the two Helmholtz resonant cavity pipes meet.

Abstract: An exhaust system for an internal combustion engine having a first exhaust tract assigned to a first group of cylinders of the internal combustion engine, and a second exhaust tract assigned to a second group of cylinders of the internal combustion engine, the first exhaust tract and the second exhaust tract being coupled to one another by a connecting line. A common bypass line branches off from the connecting line coupling the exhaust tracts.

Abstract: A control device of a motor vehicle having a noise transmission system and an exhaust system, wherein the noise transmission system has, for manipulating an interior noise of the motor vehicle, at least one intake noise transmission device which can be coupled via a first tubular connecting element to an air intake pipe leading to an internal combustion engine, the first tubular connecting element being assigned a switchable shut-off device, and which can be coupled via a second tubular connecting element to a vehicle interior, wherein the exhaust system has at least one switchable shut-off device for manipulating an exterior noise of the motor vehicle, and wherein the control device manipulates the operation of the noise transmission system and of the exhaust system jointly as a function of an actuation of a common operating element by the driver.

Abstract: A muffler for a vehicle exhaust system includes a plastic outer shell that defines an internal cavity. A metal pipe extends through the internal cavity from an inlet to an outlet. A Helmholtz chamber is formed within the plastic outer shell to attenuate a desired frequency.

Abstract: An acoustic damper is fixed to a vibration source to be provided along an outer surface of the vibration source, forms a passage that takes in air vibration generated by the vibration source, and is provided with an acoustic portion having a partition member closing the downstream side of the passage with respect to the propagation of the air vibration to serve as resistance against the air vibration, in which the acoustic portion allows air vibration to propagate in a reverse direction, and has partition members arranged so as to serve as resistance against the air vibration in respective directions. This allows to prevent from generating stress due to pressure fluctuation caused when reducing vibration, and to achieve a relatively compact size.

Abstract: A Helmholtz damper, including an enclosure, a neck extending from the enclosure, and a pipe for inserting into the neck. The portions of the pipe inserted into the neck is adjusted to regulate a resonance frequency of the Helmholtz damper.

Abstract: A device for transmitting engine sound into an interior of a motor vehicle includes a sound transmission line having a first end in acoustic communication with an air intake tract and a second end arranged to direct engine sound towards the motor vehicle interior. A sound transmitting porous media is arranged in-line with said sound transmission line and restricts airflow wherein the porous media such that airflow in the sound transmission line is required to pass through said porous media.

Abstract: In a motorcycle in which an internal combustion engine including a crankcase, a cylinder, and a cylinder head is attached to a vehicle body frame, an exhaust system includes an exhaust pipe connected to the cylinder head, and a resonator having a communication hole in communication with an inside of the exhaust pipe. The exhaust pipe is curved after being extended forward from the cylinder head and is then extended rearward in such a manner as to pass by a lateral side of the cylinder above the crankcase, while the resonator is arranged in a space between the exhaust pipe and the cylinder, and is joined to a side surface of the exhaust pipe facing inwardly of the motorcycle.

Abstract: An exhaust apparatus for internal combustion engines which can reduce exhaust noises, its weight and production cost with no need to provide a sub-muffler. The exhaust apparatus is provided with an inner pipe having the upstream open end and the downstream open end is disposed in the tail pipe, and the upstream open end of the inner pipe is protruded outwardly from the inside of the tail pipe to be extended into the resonance chamber, and thus the upstream open end is closed by the resonance chamber defined by the outer shell of the muffler, the end plate, and the partition plate.

Abstract: An exhaust apparatus for internal combustion engines which can reduce exhaust noises, its weight and production cost with no need to provide a sub-muffler. The exhaust apparatus is provided with an inner pipe having the upstream open end and the downstream open end is disposed in the tail pipe, and the upstream open end of the inner pipe is protruded outwardly from the inside of the tail pipe to be extended into the resonance chamber, and thus the upstream open end is closed by the resonance chamber defined by the outer shell of the muffler, the end plate, and the partition plate.

Abstract: A supercharger is provided, comprising a plurality of rotatable supercharger rotors each having a plurality of interleavable lobes configured to move air from an inlet to an outlet of the supercharger. Inner chambers in the lobes define an end opening and perforated end faces, at the end openings defining at least one port, having a length and a diameter. The at least one port is configured to operate with an associated air mass in the inner chamber to attenuate sound adjacent to the end opening.

Abstract: The invention relates to a blower arrangement for gas. The blower arrangement comprises a blower with a blower housing, at least one gas-inlet opening formed in the blower housing and gas-outlet opening, and at least one rotary-driven blower wheel arranged in the blower housing. Furthermore, the blower arrangement has at least one silencer device with at least one gas guiding element, wherein the gas-guiding element comprises a plurality of silencer openings and is designed as a gas guiding pipe. The gas guiding pipe varies its cross section along its longitudinal extension and has a wall, which is designed to be wave-like along the longitudinal extension of the gas guiding pipe. The silencer device also comprises at least one silencer chamber, which is in flow connection with the silencer openings and is arranged at least in sections laterally behind the gas guiding element.

Abstract: Silencing equipment provided with one or more flow channels through which cooling air flows has a flow channel forming member that forms the flow channel, and an acoustic absorbent member that is fixed to the flow channel forming member. A resonance type silencer is formed on a wall surface of the flow channel by providing a cavity for the resonance type silencer in the acoustic absorbent member and an aperture for the resonance type silencer in a portion of the flow channel forming member. The resonance type silencer sets a frequency of noise necessary to be reduced based on a peak frequency of noise generated by a fan. The silencing equipment further has a slide member which slides by a slide mechanism to adjust the area of the top of the aperture. The silencing equipment for electronic devices capable of cooling heat generating sections thereof with air has a small and simple structure and can improve a silencing effect by blowing air.

Abstract: An apparatus for damping acoustic waves that includes a volume of fluid having actively excited acoustic waves, an enclosure disposed in the volume of fluid including delimiting surfaces which define a cavity, at least one of the delimiting surfaces being permeable to the fluid, such that fluid may be exchanged between the cavity and the volume, and at least one sound producer disposed proximate the cavity to actively excite the actively excited acoustic waves in the fluid disposed in the cavity such that acoustic waves are damped in the volume.

Abstract: An exhaust system (3) of an internal combustion engine (2) is provided in a support structure (1), especially in a motor vehicle (1), with at least one exhaust pipe (8), which guides exhaust gas from the internal combustion engine (2) to the environment (4) of the support structure (1). At least one exhaust muffler (5) is provided which has at least one resonance volume (6) and at least one connection line (7), via which the respective resonance volume (6) is connected to the respective exhaust pipe (8) for transmitting airborne sound. A space-saving accommodation is obtained if at least one such resonance volume (6) is formed in a resonance chamber (9) arranged rigidly in or at the support structure (1) and if the respective connection line (7), with which the respective resonance chamber (9) is connected to the respective exhaust pipe (8), is designed as a flexible connection line and permits relative movements between the respective resonance chamber (9) and respective exhaust pipe (8).

Abstract: An acoustic resonator adaptable to a sound chamber is designed to decrease a sound pressure while increasing a particle velocity of medium particles in a low frequency range without increasing the overall size thereof. The acoustic resonator is constituted of a pipe member having one opening end and a resistance member embracing a high resistance region and a low resistance region. The resistance member is inserted into the pipe member such that one end thereof matches the opening end of the pipe member while the other end thereof is disposed at a predetermined position inside a hollow cavity of the pipe member. The high resistance region embraces an antinode region of the particle velocity distribution with respect to a standing wave occurred in the hollow cavity at a resonance frequency, thus causing an acoustic phenomenon decreasing the resonance frequency compared to a single unit of the pipe member.

Abstract: Multiple Helmholtz resonators are combined serially and dynamically to mitigate and/or overcome acoustic noise filtering problems. One Helmholtz resonator is attached to a duct having an acoustic flow path channel containing undesired acoustic signals (noise) and is considered to be an immovable Helmholtz resonator with respect to that flow channel, while at least one movable Helmholtz resonator is movably and acoustically coupled to the immovable Helmholtz resonator. The immovable and movable Helmholtz resonators are acoustically coupled together to adjustably filter two resonant frequencies in the flow path channel with a feedback control system that adjusts the position of the movable Helmholtz resonator in response to the differences in pre-filtered noise versus filtered noise.

Abstract: The invention relates to a device for metering a liquid reducing agent into an exhaust gas system for the reduction of pollutants in the exhaust gas. The device comprises a metering valve and an adapter to be mounted on an exhaust gas pipe. The metering valve is connected to the adapter by a connector element, which has at least one metal sound absorber.

Abstract: An attenuator for the air inlet tract of an internal combustion engine comprises an unobstructed tube (4) having a surrounding enclosure (9) divided into a primary chamber (11) in fluid communication with the inlet tube, and a secondary chamber (12) in fluid communication with the primary chamber. Two secondary chambers (12, 13) may be provided. The arrangement can be tuned to attenuate a wide range of frequencies.

Abstract: A method of designing/making an acoustic side branch resonator structured to be coupled to a standpipe of, for example, a nuclear power plant, wherein the acoustic side branch resonator includes a plurality of wire mesh elements for damping purposes. The method includes determining a resonant frequency of the standpipe, determining an active length of the acoustic side branch resonator using the resonant frequency, and determining a particular number of the wire mesh elements to be used in the acoustic side branch resonator and a pitch of each of the wire mesh elements using momentum and continuity equations of a compressible fluid.

Abstract: A resonator for a vehicle is provided, including a housing having at least one chamber formed therein. The housing has at least one aperture formed in a wall thereof. The housing is in fluid communication with an air conduit of the vehicle. At least one flexible member is disposed within the chamber of the housing. The flexible member includes an outer portion and an inner extension protruding from the outer portion which vibrates to attenuate low frequency sound energy transmitted from the air conduit.

Abstract: An internal combustion engine capable of efficiently supplying air to an exhaust path even in a high load state. The internal combustion engine includes a convergent section, a divergent section, and a branch section. The branch section branches a shock wave, propagating in a downstream direction at a higher velocity than exhaust gas flowing into an exhaust path from a combustion chamber when an exhaust valve is opened, from a portion of the exhaust path which is upstream with respect to the divergent section, and propagates the shock wave back to the exhaust path. The exhaust gas is caused to pass the convergent section and to collide against the shock wave between the branch section and the divergent section so as to increase the pressure of the exhaust gas in the convergent section. Such exhaust gas is caused to pass the divergent section to generate a new shock wave.

Abstract: An intake sound generation apparatus for an internal combustion engine, including an introduction duct connected to an intake passage of an intake system of the engine, a vibration member including a diaphragm portion which is vibrated by intake pulsation in the intake system, and a bellows portion configured to promote vibration of the diaphragm portion, the vibration member being so disposed as to cover one end of the introduction duct, and a resonance duct having one end connected to the introduction duct through the vibration member and the other end opened to an outside of the intake sound generation apparatus, the resonance duct acting to increase and emit a sound pressure of intake sound produced by vibration of the vibration member. A central axis of at least one of the introduction duct and the resonance duct is located offset relative to a central axis of the vibration member.

Abstract: An internal combustion engine capable of improving cleaning efficiency by preventing an increase in the temperature of the exhaust gas to lessen the deterioration of the catalyst. The internal combustion engine includes a convergent section, a divergent section, and a branch section. The branch section branches a shock wave, propagating in a downstream direction at a higher velocity than exhaust gas flowing into an exhaust path from a combustion chamber when an exhaust valve is opened, from a portion of the exhaust path which is upstream with respect to the divergent section, and propagates the shock wave back to the exhaust path. The exhaust gas is caused to pass the convergent section and to collide against the shock wave between the branch section and the divergent section, so as to increase the pressure of the exhaust gas in the convergent section. Such exhaust gas is caused to pass the divergent section to generate a new shock wave and to decrease the temperature of the exhaust gas.

Abstract: The present invention aims to provide a muffling structure of a vent pipe and a muffling structure of a case, which is capable of muffling in a wide frequency range and preventing vent resistance in the air pipe or the case from deterioration. Vent holes (11a) are formed in the peripheral wall of the vent pipe (11), a cover (12) is so provided on the peripheral wall of the vent pipe (11) as to cover the vent holes (!1a), and a bag-like body (13) in which activated charcoal (14) is contained is disposed in the space formed by the peripheral wall of the vent pipe (11) and the inner wall of the cover (12).

Abstract: An internal combustion engine includes a structure that increases the velocity of exhaust gas. The internal combustion engine includes a branch section arranged to branch a shock wave propagating at a higher velocity than exhaust gas and to guide the branched shock wave, and a reflecting section provided in the branch section. The reflecting section is arranged to reflect and return the shock wave back to an exhaust path and cause the shock wave to collide against the exhaust gas, thereby increasing the pressure of the exhaust gas. In accompaniment with the exhaust gas passing a divergent section of a convergent-divergent nozzle, a new shock wave propagating in a downstream direction in the exhaust path is generated, and the temperature and pressure of the exhaust gas are decreased.

Abstract: A gas-turbine exhaust cone includes a cone shaped outside cone 1 closed in a flow direction, an inside cone 2 arranged in the outside cone 1 over at least part of the length of the exhaust cone, with the inside cone 2 being connected to the outside cone 1 via at least one helical partition wall 3, thereby forming an interspace 4 between the outside cone 1 and the inside cone 2. The interspace 4 is connected to inlet openings 5 at its inflow side and opens at an exit side 6 towards an interior 7 of the outside cone 1. A dampening element 8 is arranged in the outside cone 1 adjacent to the exit side 6 of the interspace 4.

Abstract: A muffler combination includes two pipe units each having a cylindrical shell and having an entrance and an exit, an inlet tube connected to the entrance, an outlet tube connected to the exit, and a housing engaged in each of the cylindrical shells, the housings each include three openings formed on one side and two orifices formed on the other side, the cylindrical shells are disposed parallel to each other, and the entrance and the inlet tube of one of the cylindrical shells is located closer to the exit and the outlet tube of the other cylindrical shell whose entrance and inlet tube are located closer to the exit and the outlet tube of the cylindrical shell.

Abstract: The present invention relates to an acoustic attenuation device for an intake line of an internal combustion engine and to an intake line such as this incorporating same. An acoustic attenuation device according to the invention is intended to have a flow of pressurized gaseous fluid passing through it and comprises: a conduit structure which has a tubular wall ending in two ends, these respectively being the fluid inlet and fluid outlet ends, which are able to be incorporated into the intake line, and at least one resonance chamber which is arranged on the outside of this structure and which communicates therewith via at least one opening formed in said wall, the or each chamber being axially delimited by two transverse partitions.

Abstract: An exhaust system for a motorcycle is configured to enhance output while maintaining a necessary noise level. The exhaust system includes an exhaust pipe connected to an engine, and a silencer connected to the exhaust pipe. The silencer includes a hermetically sealed outer cylinder and an inner cylinder disposed within the outer cylinder so as to extend along an axis of the outer cylinder. The outer cylinder has a front end portion connected to the exhaust pipe and a rear end portion opened toward the atmosphere. The inner cylinder includes a reduced diameter portion with a diameter which becomes smaller in the downstream direction, a throttle portion with a constant diameter, the throttle portion being connected to the reduced diameter portion, and an enlarged diameter portion connected to the throttle portion with a diameter which becomes larger in the downstream direction.

Abstract: A piping assembly for directing fluid and mitigating acoustic and vortex coupled resonance is provided that includes a main pipe delivering fluid in a first direction; a standpipe coupled to the main pipe at an intersection; and a scoop positioned at the intersection directing the fluid towards the standpipe. A scooping insert and a method for disrupting vortex shedding in a piping assembly are also provided.

Abstract: The present invention relates to a coolant circuit of a cooling system including a pipe-shaped body defining a cavity. It has a sound absorber defining a flow channel and at least one resonator chamber which is connected to the flow channel via a connection channel. The sound absorber is an insert in the cavity of the pipe-shaped body, which forms the flow channel, the at least one resonator chamber, and the at least one connection channel.