An internal combustion engine, with an engine regulating device and an exhaust gas aftertreatment device with an SCR catalytic converter for the reduction of at least one NO.sub.x component, and with a catalytic converter regulating device, wherein the engine regulating device is prescribed a target value for an NO.sub.x mean value of the NO.sub.x component of the exhaust gases, which mean value results at an outlet point of the exhaust gas aftertreatment device in relation to a predefinable time period, and the engine regulating device is configured at least in one operating mode to continuously calculate an NO.sub.x reference value for the catalytic converter regulating device with consideration of No.sub.x components which have already been emitted and the predefined target value, which reference value is selected in such a way that the predefined target value results at the outlet point of the exhaust gas aftertreatment device at the end of the predefinable time period when the calculated NO.sub.x reference value of the catalytic converter regulating device is fed as NO.sub.x setpoint value to the regulating means.

Systems and methods for diagnosing an exhaust aftertreatment system are provided. A controller determines, for each sensor of a plurality of sensors, one or more performance parameters based on measurement data obtained from the sensor that is indicative of a performance of the sensor or a component of the exhaust aftertreatment system. The controller determines, for each performance parameter, a corresponding degradation level indicator indicative of a performance degradation of the corresponding sensor or the corresponding component of the exhaust aftertreatment system. The controller can determine, for each degradation level indicator, a corresponding diagnosis threshold value for detecting an operational state of the corresponding sensor or the corresponding component of the exhaust aftertreatment system. The controller can determine a multipoint diagnosis threshold value based on the diagnosis threshold values, and determine an operational state of the aftertreatment system using the multipoint diagnosis threshold value.

A method comprises determining that an aftertreatment system is in a cold-operation mode; initiating a low engine-out NOx (LEON) mode by controlling a component of a vehicle containing the aftertreatment system to decrease an instantaneous engine out NOx (EONOx) amount and to increase exhaust energy relative to a normal operation mode for an engine of the vehicle; receiving information indicative of an operating status of the vehicle during the LEON mode; disengaging the LEON mode; subsequent to disengaging the LEON mode, initiating a thermal management (TM) mode for the aftertreatment system, wherein the TM mode is initiated by controlling a component of the vehicle to increase fueling to the engine for a power level by reducing engine efficiency and directing excess fuel to the aftertreatment system; receiving information indicative of an operating status of the vehicle during the TM mode; and disengaging the TM mode.

The present disclosure relates to a method for controlling the propulsion of a ship (10). The ship (10) comprises an engine (5) and a controllable pitch propeller (7), wherein torque and engine speed are adjusted to correspond to an output set point value. The adjustment is such that the ship (10) is operated in an operating condition with an engine speed of the engine (5) and a propeller pitch of the controllable pitch propeller (7) such that the fuel consumption of the ship (10) is brought and/or held within a desired fuel consumption range. The method comprises determining a top pressure value indicative of a top pressure in at least one cylinder (9) and reducing the torque of the engine (5) upon detection that the lop pressure value exceeds a top pressure threshold value.

An internal combustion engine (1), with an engine regulating device (3) and an exhaust gas aftertreatment device (16) with an SCR catalytic converter (4) for the reduction of at least one NO.sub.x component, and with a catalytic converter regulating device (6), wherein the engine regulating device (3) is prescribed a target value for an NO.sub.x mean value of the NO.sub.x component of the exhaust gases, which mean value results at an outlet point (7) of the exhaust gas aftertreatment device (16) in relation to a predefinable time period, and the engine regulating device (3) is configured at least in one operating mode to continuously calculate an NO.sub.x reference value for the catalytic converter regulating device (6) with consideration of No.sub.x components which have already been emitted and the predefined target value, which reference value is selected in such a way that the predefined target value results at the outlet point of the exhaust gas aftertreatment device (16) at the end of the predefinable time period when the calculated NO.sub.x reference value of the catalytic converter regulating device (6) is fed as NO.sub.x setpoint value to the regulating means.

A combustion mode module is configured to switch operation of a low-temperature combustion (LTC) engine between a spark ignition (SI) mode, a positive valve overlap (PVO) mode, and a negative valve overlap (NVO) mode. A spark control module is configured to control a spark plug to generate a spark in a cylinder of the LTC engine when the LTC engine is operating in the SI mode. A valve control module is configured to control intake and exhaust valves of the cylinder to yield a PVO and a NVO when the LTC engine is operating in the PVO mode and the NVO mode, respectively. An air/fuel (A/F) control module is configured to adjust a desired A/F ratio of the LTC engine to a rich A/F ratio when operation of the LTC engine is switched to the PVO mode from either one of the SI mode and the NVO mode.

A combustion mode module is configured to switch operation of a low-temperature combustion (LTC) engine between a spark ignition (SI) mode, a positive valve overlap (PVO) mode, and a negative valve overlap (NVO) mode. A spark control module is configured to control a spark plug to generate a spark in a cylinder of the LTC engine when the LTC engine is operating in the SI mode. A valve control module is configured to control intake and exhaust valves of the cylinder to yield a PVO and a NVO when the LTC engine is operating in the PVO mode and the NVO mode, respectively. An air/fuel (A/F) control module is configured to adjust a desired A/F ratio of the LTC engine to a rich A/F ratio when operation of the LTC engine is switched to the PVO mode from either one of the SI mode and the NVO mode.

A process for testing a plurality of components of an exhaust gas aftertreatment system (100) is disclosed, wherein the plurality of components comprises a first SCR catalyst and at least one further SCR catalyst arranged downstream of the first SCR catalyst in the flow direction of exhaust gas to be passed through the exhaust gas aftertreatment system, a first NOx sensor assigned to the first SCR catalyst and at least one further NOx sensor and a first DeNOx element assigned to the first SCR catalyst and at least one further DeNOx element and wherein the process comprises at least the following steps: conditioning the SCR catalysts, testing the NOx sensors, testing the DeNOx systems testing a storage capacity for the reductant of the SCR catalysts.

Provided is an engine system including: a bypass pipe (bypass flow passage) connecting an upstream side and a downstream side of the turbine on an exhaust flow passage; a bypass valve configured to open and close the bypass flow passage; and a catalytic activation controller configured to control the bypass valve and a compression ratio of a combustion chamber.

A catalyst deterioration diagnosis device includes: a unit configured to obtain a temperature of a catalyst; a unit configured to obtain a sensor output from a gas sensor disposed between the catalyst and an exhaust port; and a unit configured to determine the catalyst to be faulty when the temperature of the catalyst obtained when the sensor output becomes a preset evaluative output is equal to or higher than an evaluative catalyst temperature.