An air intake system for a commercial vehicle is disclosed. The air intake system includes a hood with at least one frontal intake opening through which air to be guided to an engine of the commercial vehicle can flow and with at least one plenum configured to receive air flowing through the intake opening. The air intake system further includes at least one air pipe having at least one air duct with at least one inlet opening through which the air flowing through the frontal intake opening can flow, the air duct arranged upstream of and fluidically connected with the plenum so as to guide the air to and into the plenum. The air intake system additionally includes at least one air filter and at least one silencer plate arranged upstream of the air filter, the silencer plate having a plurality of through openings through which the air can flow.

The invention relates to an intake device for a compressor. The intake device comprises a support structure having a plurality of struts which are arranged in the circumferential direction about an axis of the support structure and extend in the radial direction. Furthermore, the intake device comprises a plurality of first sound-damping elements which are arranged in the radial continuation of the plurality of struts. In addition, the intake device comprises a plurality of second sound-damping elements, each of which is arranged between adjacent first sound-damping elements. The invention furthermore relates to an exhaust-gas turbocharger having the intake device according to the invention, and an internal combustion engine having an exhaust-gas turbocharger of this kind.

A filter muffler includes a front element, a rear element, and a plurality of damping elements arranged between the front element and the rear element, where the damping elements are arranged radially around a central axis of the filter muffler such that a flow channel is formed between adjacent damping elements, where respective outflow-side ends of the damping elements have a diffuser element which has an outflow-side tapering, and where an angle α between two opposite sides of the diffuser element is selected from a range of 1°≤α≤8°.

An apparatus for reducing flow noise of an air intake system of a vehicle is provided as an assembly of a body member and a cover member. An acoustic metamaterial unit includes a chamber having a predetermined size, an inlet flow path, and an outlet flow path provided therein and is connected to a pipe of an air intake system. The apparatus advantageously reduces or removes high-frequency flow noise occurring in a turbocharger by using the acoustic metamaterial unit. The size and shape of the acoustic metamaterial unit is standardized such that the acoustic metamaterial unit is used compatibly regardless of the type of vehicles, which can make it possible to advantageously reduce costs and improve salability.

An air induction system includes an air duct and an air permeable membrane. The air duct is configured to deliver intake air to an engine. The air duct includes a cylindrical wall defining a bore and an enclosure projecting from an outer radial surface of the cylindrical wall and defining a cavity therein. The cylindrical wall has an opening extending therethrough that enables airflow from the bore to the cavity in the enclosure. The air permeable membrane is configured to cover the opening in the cylindrical wall.

A duct includes a circumferential wall. At least part of the circumferential wall is a fibrous portion that includes fibers. The fibrous portion includes a breathable inner layer located on an inner circumferential side in the circumferential wall and an outer layer located on an outer circumferential side of the inner layer in the circumferential wall. The outer layer is less breathable than the inner layer. A boundary between the inner layer and the outer layer is breathable.

The invention relates to an exhaust gas turbocharger with a silencer. The silencer comprises a multiplicity of damping elements which are arranged concentrically about a central axis of the silencer and are spaced apart concentrically from one another, with the result that a flow duct is formed in each case between adjacent damping elements. The flow duct has an inlet which is at a greater radial spacing from the central axis than an outlet of the flow duct.

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.

A high frequency attenuating device for an air flow induction system of a vehicle employing a thermoformed fibrous mat of any shape that fits robustly inside the duct. The dissipative nature of the fibrous mat helps in achieving broadband attenuation in the high frequency regime. The ability to manufacture the fibrous mat into any shape helps with restriction, targets different attenuation bands, and makes it more feasible to manufacture. Hybrid solutions are possible when combined with low frequency perforated silencers or high frequency QWT arrays injection molded onto them.

An air intake device includes a bypass passage which makes a portion of an air intake passage on an upstream side of a compressor and a portion of the air intake passage on a downstream side of the compressor communicate with each other, and a bypass passage open/close valve which opens or closes the bypass passage. The air intake passage includes a first passage extending toward an upstream side from the compressor along a first direction, a bent portion bent from an upstream end of the first passage in a second direction, and a second passage extending from an upstream end of the bent portion along the second direction. The second passage has a vertically elongated cross-sectional shape. A vibration suppressing part for suppressing vibrations of the second passage is disposed in at least one of the second passage and the bent portion.