An engine intake structure comprises an intake passage member 18 which defines an intake passage 36 for supplying air to an internal combustion engine 12, and which also defines a resonator chamber 40 in communication with the intake passage 36; and an in-vehicle device 14 located in an engine room 10 of a vehicle and having a preset reference temperature for temperature control, the intake passage member 18 being located above and adjacent to the in-vehicle device 14. The intake passage 36 extends above the in-vehicle device 14 so as to at least partially overlap the resonator chamber 40 as viewed in a vertical direction, thereby forming a two-layer structure, which makes the in-vehicle device 14 less affected by ambient temperature in the upper part of the engine room 10.

Methods and systems are presented for diagnosing a breach of an evaporative emissions system. The methods and systems include repurposing a resonator as a vacuum reservoir to reduce a pressure of an evaporative emissions system so that it may be determined if there is or is not a breach of the evaporative emissions system.

An acoustic component is provided with a flow channel for a fluid. The flow channel has an inlet pipe and an outlet pipe. A flow channel section is arranged between the inlet pipe and the outlet pipe, wherein the flow channel section has a silencer volume connected in the flow channel section via openings to the flow channel. A flow deflection device is arranged at least in the flow channel section with the silencer volume, wherein the flow deflection device deflects a flow of the fluid in the flow channel section with the silencer volume away from the openings. The openings in the flow channel section are arranged in a sheltered zone of the flow deflection device.

An intake system of an engine is provided, including a first passage provided to an engine bay, for leading fresh air to the engine, a second passage branched from a branching part at an intermediate location of the first passage, and extending toward a cabin, and an intake noise increasing device provided to the second passage, and configured to increase intake pressure in response to an intake air pressure wave. The intake noise increasing device has a cylindrical bellows part configured to expand and contract in a cylindrical axis direction, and a vibrating membrane formed integrally with the bellows part to close a first opening of the bellows part. The second passage has an introducing passage section connected to a second opening of the bellows part, and extending toward the branching part, and the introducing passage section is disposed so as to be lowered while separating from the bellows part.

An intake system of an engine is provided, which includes a first passage provided to an engine bay, for leading fresh air to the engine, a second passage branched from the first passage and extending toward a cabin, and an intake noise increasing device provided to the second passage. The intake noise increasing device has a cylindrical bellows part, a vibrating membrane formed integrally with the bellows part to close a first opening of the bellows part, and an outer circumferential case provided to cover an outer circumference of the bellows part and configured to allow the expansion and contraction of the bellows part therein. The second passage has a deriving passage section connected to a part of the outer circumferential case on a first opening side and extending toward the cabin. The deriving passage section is disposed to be lowered while separating from the intake noise increasing device.

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.

A bracket 10 has a U-shaped cross section in which a pair of facing plate portions 15 extend from both side edges of a bottom plate portion 12 so as to face each other, and is fixed to a vehicle body side for mounting a predetermined component. The bottom plate portion 12 and the pair of facing plate portions 15 partition a bracket inner space 16, and the bottom plate portion 12 is provided with a through hole 20 which makes the bracket inner space 16 communicate with an outside. A resonator 23 is fixed to the bracket 10 in a state where the resonator 23 is accommodated in the bracket inner space 16. A ventilation passage 29 makes the resonator 23 communicate with the intake duct 21 through the through hole 20.

An intake system of a vehicle is configured so that air moves along a ‘U’-shaped movement path from an entrance of an intake duct portion into which outside air is introduced to a position where a filter is mounted, and is configured so that the intake duct portion, an air cleaner body portion, and an external resonator are formed integrally with each other.

An apparatus of amplifying sound waves may include a metamaterial structure having a metamaterial inside thereof, an inlet through which air flows into the metamaterial structure, and a penetration portion formed to penetrate a portion of one side of the metamaterial structure, a membrane member coupled to the penetration portion, and a resonance member surrounding the membrane member and coupled to the metamaterial structure and including a space inside thereof and a discharge port fluidically communicating with an outside thereof and the internal space.

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.