The invention relates to a method for monitoring at least one exhaust gas turbocharger (ATL) of a large internal combustion engine (BKM), comprising at least one compressor (1a) and one exhaust gas turbine (1b) arranged on the same shaft as the compressor, wherein the current pressures (p.sub.1, p.sub.2) upstream and downstream of the compressor (1a) and the current temperatures (T.sub.1, T.sub.4) upstream of the compressor (1a) and upstream of the exhaust gas turbine (1b) are measured. In order to monitor an exhaust gas turbocharger effectively and as simply as possible, the current pressures (p.sub.4, p.sub.5) upstream and downstream of the exhaust gas turbine (1b), the current temperatures (T.sub.2, T.sub.5) downstream of the compressor (1a) and downstream of the exhaust gas turbine (1b), and the rotational speed (n.sub.A) of the exhaust gas turbine (1b) are measured, preferably continuously, the efficiencies (.sub.) of the compressor (1a) and of the exhaust gas turbine (1b) are calculated from the measured data, and a diagnostic algorithm is started when a worsening of the efficiency (.sub.TV, .sub.T) of the compressor (1a) and/or of the exhaust gas turbine (1b) is detected or after a defined time interval has elapsed.

Methods and systems are provided for a turbocharger of an engine. In one example, a method may include balancing a pressure differential between compressor wheels of the turbocharger.

Methods and systems are provided for a turbocharger of an engine. In one example, a method may include balancing a pressure differential between compressor wheels of the turbocharger.

A compressor recirculation valve having features for mitigating the rush noise caused when the valve opens and compressed recirculation air rushes through the valve into the compressor inlet. The features for mitigating rush noise include a generally annular wall that projects from the valve seat and surrounds the valve member. The radially inner surface of the wall can be conical and can include radially inwardly projecting teeth between which are V-shaped grooves.

A compressor recirculation valve having features for mitigating the rush noise caused when the valve opens and compressed recirculation air rushes through the valve into the compressor inlet. The features for mitigating rush noise include a generally annular wall that projects from the valve seat and surrounds the valve member. The radially inner surface of the wall can be conical and can include radially inwardly projecting teeth between which are V-shaped grooves.

Methods and systems are provided for selecting a location for water injection during a water injection event based on ambient temperature and humidity, as well as engine operating conditions. In one example, a method may include injecting water upstream of a charge air cooler in response to operating the cooler in heater mode and injecting water downstream of the cooler in response to operating the cooler in cooler mode. Further, the method may include operating the cooler in heater mode based on dry, cold ambient conditions and a dilution demand and operating the cooler in cooler mode based on engine boost conditions and engine knock.

A turbocharger with a turbine (10) having a turbine wheel (12) in a turbine housing (14) with an associated manifold (24) having individual ports (22) corresponding to unobstructed passageways (26) from each cylinder of an engine. The ports (22) are substantially equally spaced around a face of the turbine wheel (12) to preserve benefits of pulses without interference.

A turbocharger with a turbine (10) having a turbine wheel (12) in a turbine housing (14) with an associated manifold (24) having individual ports (22) corresponding to unobstructed passageways (26) from each cylinder of an engine. The ports (22) are substantially equally spaced around a face of the turbine wheel (12) to preserve benefits of pulses without interference.

An acoustic damper includes an upstream wall with an inlet aperture and a downstream wall with an outlet aperture. The acoustic damper includes a first resonator that is supported by at least one of the upstream wall and the downstream wall. The acoustic damper also includes a second resonator that is supported by at least one of the upstream wall and the downstream wall. The first resonator and the second resonator are arranged in-parallel. Also, the first resonator and the second resonator are configured to cooperatively attenuate acoustic energy associated with a fluid flowing from the inlet aperture to the outlet aperture.

An acoustic damper includes an upstream wall with an inlet aperture and a downstream wall with an outlet aperture. The acoustic damper includes a first resonator that is supported by at least one of the upstream wall and the downstream wall. The acoustic damper also includes a second resonator that is supported by at least one of the upstream wall and the downstream wall. The first resonator and the second resonator are arranged in-parallel. Also, the first resonator and the second resonator are configured to cooperatively attenuate acoustic energy associated with a fluid flowing from the inlet aperture to the outlet aperture.