A method and device for operating an internal combustion engine having a supercharging system that has an exhaust turbocharger and an electrically driven compressor. An output of the exhaust turbocharger is adjustable by a control element. A boost pressure setpoint is determined for achieving an increased engine torque setpoint. The supercharging system is adjusted to build up the actual boost pressure in accordance with the boost pressure setpoint and a positive scavenging gradient in a cylinder of the internal combustion engine is adjusted as the overriding command variable for driving the supercharging system.

An internal combustion engine includes a cylinder block including a cylinder, a cylinder head including an intake port, the intake port communicating with the cylinder, an intake manifold fixed to the cylinder head, the intake manifold being configured to supply intake air into the cylinder, and a dynamic vibration absorber configured to suppress vibration of the intake manifold. A direction that is orthogonal to both a central axis of the cylinder and a rotational axis of a crankshaft of the internal combustion engine is defined as a width direction. The dynamic vibration absorber is attached to the intake manifold on an opposite side of a center of gravity of the intake manifold from the cylinder head in the width direction.

A V-type internal combustion engine has a first cylinder bank with four first cylinders and a second cylinder bank with four second cylinders. A first fresh gas line is provided for the first cylinder bank and a second fresh gas line for the second cylinder bank. An exhaust gas system has a first turbocharger, which has a first compressor and a first turbine having two first exhaust gas inlets, and a second turbocharger, which has a second compressor and a second turbine having two second exhaust gas inlets. The first fresh gas line is connectable to the first four cylinders downstream of the first compressor in the flow direction of a fresh gas so as to conduct fresh gas, and the second fresh gas line is connectable to the second four cylinders downstream of the second compressor in the flow direction of the fresh gas so as to conduct fresh gas. A first cylinder and a second cylinder can be connected via the exhaust gas system to the first first exhaust gas inlet, a first cylinder and a second cylinder can be connected via the exhaust system to the second first exhaust gas inlet, a first cylinder and a second cylinder can be connected via the exhaust gas system to the first second exhaust gas inlet, and a first cylinder and a second cylinder can be connected via the exhaust gas system to the second second exhaust gas inlet. A single third compressor is arranged in the first fresh gas line between the first compressor and the first four cylinders.

An internal combustion engine includes: an engine body (10) having at least one cylinder; and an air-supply manifold (4) including an adjustment pipe (12). The length of the adjustment pipe is set so that a first pressure wave (14A) propagating from the air-supply manifold toward the adjustment pipe and a second pressure wave (14B) propagating from the adjustment pipe toward the air-supply manifold have opposite phases from each other at the cylinder.

An internal combustion engine includes: an engine body (10) having at least one cylinder; and an air-supply manifold (4) including an adjustment pipe (12). The length of the adjustment pipe is set so that a first pressure wave (14A) propagating from the air-supply manifold toward the adjustment pipe and a second pressure wave (14B) propagating from the adjustment pipe toward the air-supply manifold have opposite phases from each other at the cylinder.

An engine includes an exhaust gas control apparatus that is configured to store NOx and react NOx with a reduction agent. A control device for the engine includes an electronic control unit. The electronic control unit is configured to: (i) execute a rich spike control, the rich spike control is a control executed to temporarily change an in-cylinder air-fuel ratio from a leaner air-fuel ratio than the stoichiometric air-fuel ratio to the stoichiometric air-fuel ratio or a richer air-fuel ratio than the stoichiometric air-fuel ratio, and (ii) vary an overlap amount of an intake valve and an exhaust valve such that the overlap amount is less during execution of the rich spike control than during non-execution of the rich spike control, in an operation range where a pressure of the intake port becomes higher than a pressure of the exhaust port.

A variable intake system includes a pair of surge tanks connected in a communicating manner to a main intake pipe through a low speed communication pipe and a high speed communication pipe, a middle speed communication pipe for connecting the pair of surge tanks, and a noise reducing member integrally provided at the middle speed communication pipe to reduce noise.

An internal combustion engine includes a crankcase including a crankshaft and at least one cylinder coupled to the crankcase. The at least one cylinder has an intake port and defines an internal combustion chamber. The engine further includes a throttle body assembly with a throttle valve coupled to the intake port of the at least one cylinder and a throttle plate. Additionally, the engine includes a supplementary air inlet fluidly coupled to the intake port and spaced apart from the throttle valve. The supplementary air inlet is configured to receive a flow of air from a location downstream of the throttle plate when the throttle plate is in a fully closed position and the flow of air is directed into the combustion chamber through the intake port for combustion therein.

Disclosed is a control device for an engine provided with a first intake valve and a second intake valve in an intake port. The control device comprises: a variable valve operating mechanism (72) configured to control a valve opening timing and a valve closing timing of an intake valve (21a); and a variable valve operating mechanism (72) configured to control a valve opening timing and a valve closing timing of an intake valve (21b), independently of the intake valve (21a). The latter variable valve mechanisms (72) is operable, in an intake stroke of the engine, to close the intake valve (21b) after the elapse of a delay time rt since the intake valve (21a) is closed. The delay time rt is a time period during which a pressure wave generated upon closing of the intake valve (21a) reaches the intake valve (21b) through the intake port (16).

Disclosed is a fluid accelerator provided on a fluid flow path so as to improve the fluid flow velocity. To this end, provided is a fluid accelerator comprising: a body formed in a cylindrical structure so as to be provided on a fluid flow path; a center hole forming a venturi passage in the vertical direction in the center of the body and having a helical guide groove provided on the inner circumferential surface of the venturi passage; and a plurality of middle holes formed in the vertical direction of the body along the edge of the center hole around the center hole. The fluid accelerator of the present invention can be easily provided in conventional device using fluid, thereby improving the fluid velocity.