A rotating electrical machine such as a generator has a rotor disposed within a rotor housing and an air flow path passing from the rotor housing to and through a silencer to an exhaust. The silencer comprises at least one air flow path disposed adjacent at least one sound absorbing column, the column comprising a first portion having a first sound absorbing material therein and a second portion having a microperforated panel (MPP) and a resonator cavity. The second portion comprises a reactive sound absorbing unit which can be specifically tuned to suppress aero-acoustic noise generated by ventilation slots in the rotor, typically peaks at 100 Hz or 120 Hz.

A vehicle exhaust system includes a component housing defining an internal cavity and at least one exhaust gas treatment element positioned within the internal cavity. A resonator volume is connected in parallel with the internal cavity via at least one resonator element and insulating material is located within the resonator volume.

A noise muffler for an air moving device can include a housing with a housing inlet, a housing outlet, and at least a first foam component and a second foam component. The first foam component and the second foam component are placed within a cavity of the housing and define an air passageway. The first foam component and the second foam component redirect air flow through the cavity in three dimensions in order to muffle noise generated by the air moving device.

A noise muffler for an air moving device can include a housing with a housing inlet, a housing outlet, and at least a first foam component and a second foam component. The first foam component and the second foam component are placed within a cavity of the housing and define an air passageway. The first foam component and the second foam component redirect air flow through the cavity in three dimensions in order to muffle noise generated by the air moving device.

The muffler for a motorized vehicle includes a housing with an inlet chamber and an outlet chamber, an exhaust inlet, and an exhaust outlet. The muffler includes a first channel with a first noise dampening amount that is within the housing interior, to fluidly connect the inlet chamber and the outlet chamber. The muffler includes second channel with a second noise dampening amount that is within the housing interior between the inlet chamber and the outlet chamber. The first noise dampening amount is greater than the second noise dampening amount. A valve selectively fluidly connects the inlet chamber and the outlet chamber thorough the second channel, and is configured to variably obstruct the flow of exhaust gas through the second channel. In various embodiments, the muffler has more than one inlet chamber and more than one exhaust outlet.

The muffler for a motorized vehicle includes a housing with an inlet chamber and an outlet chamber, an exhaust inlet, and an exhaust outlet. The muffler includes a first channel with a first noise dampening amount that is within the housing interior, to fluidly connect the inlet chamber and the outlet chamber. The muffler includes second channel with a second noise dampening amount that is within the housing interior between the inlet chamber and the outlet chamber. The first noise dampening amount is greater than the second noise dampening amount. A valve selectively fluidly connects the inlet chamber and the outlet chamber thorough the second channel, and is configured to variably obstruct the flow of exhaust gas through the second channel. In various embodiments, the muffler has more than one inlet chamber and more than one exhaust outlet.

Systems for and methods of evacuating air from a muffler while it is being filled with a fibrous material are disclosed.

Systems for and methods of evacuating air from a muffler while it is being filled with a fibrous material are disclosed.

An exhaust component for a motor vehicle includes a wall, an internal volume, an inlet, and an outlet. The wall includes a core layer having a surface and a first layer disposed on a portion of the surface. The portion is less than 100 percent of an area of the surface. The core layer has a first composition. The first layer is a cold-sprayed layer. The core layer has a second composition different from the first composition. The first layer reduces surface-radiated noise from the exhaust component during operation of the motor vehicle. The internal volume is at least partially defined by the wall. The inlet is in fluid communication with the internal volume. The outlet is in fluid communication with the internal volume.

An exhaust system includes a housing comprising a first housing portion and a second housing portion separated by a common wall. The first housing portion has a first exhaust passage therethrough. The first exhaust passage has a first inlet receiving exhaust gasses from a turbocharger. The second housing portion has a second exhaust passage therethrough. The second exhaust passage has a second inlet receiving gasses from an exhaust bypass valve. The first passage and the second passage are non-intersecting within the housing.