A muffler for use with an internal combustion engine is provided. The muffler includes a first tube configured to receive a first exhaust stream. The first tube includes a first inlet portion, a first outlet portion spaced apart from the first inlet portion, and a first intermediate portion extending between the first inlet portion and the first outlet portion. The muffler also includes a second tube configured to receive a second exhaust stream. The second tube includes a second inlet portion, a second outlet portion spaced apart from the second inlet portion, and a second intermediate portion extending between the second inlet portion and the second outlet portion. The first intermediate portion and the second intermediate portion cross each other, are at least partially stacked on each other, and are in fluid communication with each other.

Provided is a tail pipe in which a silencing effect at a discharge port is obtained. One aspect of the present disclosure is a tail pipe including: an inner tube including a discharge port configured such that an exhaust gas is discharged therefrom; an outer tube arranged so as to form a space between the outer tube and the inner tube by surrounding an outer peripheral surface of the inner tube, an upstream end of the outer tube in a flow direction of the exhaust gas being closed; and at least one communication hole allowing communication between an interior of the inner tube and the space.

An exhaust gas treatment assembly includes a housing and an exhaust gas treatment section accommodating chamber in the housing for accommodating an exhaust gas treatment section therein so as to permit the treatment section to be removed from the housing. An exhaust gas supply duct leads to the housing and is open to the housing via a housing inlet region. A main mixing section accommodating chamber accommodates a main mixing section in such a way that the main mixing section can be removed from the housing. A first exhaust gas treatment section inlet region is open to the housing inlet region to receive exhaust gas from the exhaust gas supply duct. A first exhaust gas treatment section outlet region is open to a main mixing section exhaust gas inlet region of the main mixing section.

Apparatuses and methods for tuning a muffler. An apparatus comprises a housing for a muffler, a first inlet pipe, and a second inlet pipe. The housing includes a coupling chamber. The first inlet pipe has a first set of physical features and carries exhaust to the coupling chamber. The second inlet pipe has a second set of physical features and carries the exhaust to the coupling chamber. The first set of physical features varies from the second set of physical features with respect to at least one physical feature such that a first sound waveform passing through the first inlet pipe and a second sound waveform passing through the second inlet pipe are uniquely tuned to thereby tune an overall sound waveform emitted by the muffler.

A saddle-riding type vehicle exhaust structure includes: an exhaust pipe that is connected to an exhaust port connecting to a combustion chamber of an engine and has a circular cross-sectional shape which is orthogonal to an exhaust flow direction; and a muffler that is connected to a downstream side in the exhaust flow direction of the exhaust pipe, wherein the exhaust pipe includes a muffler connection part that is connected to the muffler, an exhaust pipe upstream part that is connected to an upstream side in the exhaust flow direction of the muffler connection part, and an exhaust pipe downstream part that is connected to a downstream side in the exhaust flow direction of the muffler connection part, a cross-sectional area that is orthogonal to the exhaust flow direction of the muffler connection part is larger than each of a minimum value of a cross-sectional area that is orthogonal to an exhaust flow direction of the exhaust pipe upstream part and a minimum value of a cross-sectional area that is orthogonal to an exhaust flow direction of the exhaust pipe downstream part, and a vehicle width direction size of the cross-sectional shape of the muffler connection part and a vertical direction size of the cross-sectional shape of the muffler connection part are different from each other.

In an exhaust gas processing device, an air-fuel ratio sensor is provided such that a measuring portion is located in a region surrounded by a downstream-side end surface of a TWC, an upstream-side end surface of a GPF, and an inner wall surface of a case against which the exhaust gas G that has passed through the TWC flows, that is the region a region on the GPF side of the center of the TWC.

In an exhaust gas purification filter, a partition wall has communicating pores. Each communicating pore has a surface opening on the gas-inflow-side surface and a plurality of portions, each portion having a diameter being reduced and then increased from the surface opening, one of the portions, whose diameter is the smallest, being defined as an inlet neck portion. As viewed in cross section in a thickness direction of the partition wall, the surface opening of each communication pore has a diameter defined as a surface opening diameter, the inlet neck portion of each communication pore has a diameter defined as an inlet neck diameter. The inlet neck diameter is smaller than the surface opening diameter, and an average value of the inlet neck diameters is 15 μm or less. A surface opening ratio of the communicating pores in plan view of the gas-inflow-side partition wall surface is 40% or more.

An exhaust muffler includes a first muffler section having a tubular member made up of an inner pipe to which an exhaust pipe is connected and an outer pipe covering the inner pipe, and a connector connecting the tubular member and a second muffler section to each other, and the second muffler section having an outer shell, a first partition wall, a second partition wall, and a third partition wall. Exhaust gases delivered from the exhaust pipe are discharged from the first muffler section and the second muffler section out of the exhaust muffler. The second muffler section has a cross-sectional area larger than a cross-sectional area of the tubular member. The exhaust muffler includes a first expansion chamber, a second expansion chamber, and a third expansion chamber. The second muffler section includes a fluid communication pipe extending through the first partition wall and the second partition wall for leading exhaust gases from the first expansion chamber into the second expansion chamber, and an exhaust passage pipe held in fluid communication with the third expansion chamber and extending through the second partition and the third partition wall. The second partition wall has a fluid communication hole defined therein that provides fluid communication between the second expansion chamber and the third expansion chamber. There is thus provided an engine exhaust device capable of increasing a silencing capability by increasing the length of a route through which the exhaust gases flow while maintaining the length of the exhaust device.

A dust removal method for engine exhaust gas includes the steps of using an exhaust gas ionization dust removal electric field to gather particles in the exhaust gas, and using same to charge an exhaust gas electret element (205). The exhaust gas electret element (205) is close to or is provided at an outlet of an exhaust gas electric field device (1021). The dust removal method for engine exhaust gas can efficiently treat the engine exhaust gas and exhaust gas emissions.

An engine exhaust dust removal system includes an exhaust dust removal system inlet, an exhaust dust removal system outlet and an exhaust electric field device. The engine exhaust dust removal system has a good dust removal effect and is able to effectively remove particulate matters from the engine exhaust.