An engine system and method for operating an internal combustion engine in dynamically varying conditions. An exemplary system comprises an internal combustion engine configured to receive both a primary fuel and a secondary fuel into one or more chambers in which a combustion process occurs, a fuel injection system, an air intake manifold and a fuel manifold; an electronic system which controls timing and metering of the primary fuel and/or the secondary fuel in the combustion process; and a plurality of sensors positioned to measure one or more variables associated with combustion of the primary fuel in the presence of the secondary fuel. The electronic system is configured to apply a control signal to adjust an engine setting to reduce NOx emissions based in part on the magnitude of the variable.

A control apparatus for a compression autoignition engine controls compression autoignition by ignition. The control apparatus includes an injector, a spark plug, and a controller. The controller controls the injector so that fuel is injected by a plurality of divided injections, and thereafter, outputs a control signal to the spark plug at predetermined ignition timing so that, by ignition, unburned air-fuel mixture combusts by autoignition. Control is performed so that, when load on the engine is high, an amount of fuel injected at later timing among the plurality of injections becomes larger than when the load is low.

A control apparatus for a compression autoignition engine controls compression autoignition by ignition. The control apparatus includes an injector, a spark plug, and a controller. The controller controls the injector so that fuel is injected by a plurality of divided injections, and thereafter, outputs a control signal to the spark plug at predetermined ignition timing so that, by ignition, unburned air-fuel mixture combusts by autoignition. Control is performed so that, when load on the engine is high, an amount of fuel injected at later timing among the plurality of injections becomes larger than when the load is low.

A fuel oxygen conversion unit includes a contactor defining a liquid fuel inlet, a stripping gas inlet and a fuel/gas mixture outlet. The fuel oxygen conversion unit also includes a fuel/gas separator defining a fuel/gas mixture inlet in flow communication with the fuel/gas mixture outlet of the contactor, an axial direction, and a radial direction. The fuel/gas separator includes a separator assembly including a core including a gas-permeable section extending along the axial direction and defining a maximum diameter, the maximum diameter of the gas-permeable section being substantially constant along the axial direction; and a stationary casing, the fuel/gas separator defining a fuel/gas chamber in fluid communication with the fuel/gas mixture inlet at a location inward of the stationary casing and outward of the gas-permeable section of the separator assembly along the radial direction.

A control apparatus for an engine includes an engine, a state quantity setting device, an injector, a spark plug, and a controller. The controller sets a G/F in a range from 18 to 50. After the spark plug ignites air-fuel mixture, unburned air-fuel mixture is combusted by autoignition.

In an EGR device configured to reflux part of exhaust gas of the engine as EGR gas into intake air of the engine, an EGR valve configured to restrict a flow rate of the EGR gas is closed when rotation speed N of the engine is between a low-speed threshold and a high-speed threshold, and fuel injection rate is between a low-injection rate threshold and a high-injection rate threshold that are set for each rotation speed.

Methods and systems are provided for adjusting a throttle based on an intake oxygen sensor output. In one example, a method may include adjusting a position of a throttle based on a dilution threshold and a total aircharge dilution level, the total dilution aircharge level based on an output of an intake oxygen sensor. Additionally, spark timing may be adjusted based on the total aircharge dilution level.

An object is to provide a control device for an internal combustion engine, at an inexpensive price, whereby it is possible to suppress a decrease in the exhaust gas performance of the internal combustion engine due to an environmental change or damage from aging. The present invention relates to a control device for an internal combustion engine which controls an EGR amount by adjusting an opening degree of an EGR valve (20) disposed in an EGR channel (16), the control device comprising temperature detection units (24, 26, 30), a pressure detection unit (28), a unit (48) to calculate a basic opening degree of the EGR valve, a unit (44, 56) to calculate an estimate value of at least one of an air-excess ratio or an intake oxygen concentration on the basis of detection values obtained by the temperature detection units and the pressure detection unit, a unit (46, 48) to calculate a target value of the estimate value, a unit (50) to calculate a correction factor K on the basis of the estimate air-excess ratio s and the target air-excess ratio t, a unit (52) to calculate the opening-degree command value D for the EGR valve on the basis of the basic opening degree Db and the correction coefficient K, and a unit (54) to control the EGR valve on the basis of the opening-degree command value D.

An engine system and method for operating an internal combustion engine in dynamically varying conditions. An exemplary system comprises an internal combustion engine configured to receive both a primary fuel and a secondary fuel into one or more chambers in which a combustion process occurs, a fuel injection system, an air intake manifold and a fuel manifold; an electronic system which controls timing and metering of the primary fuel and/or the secondary fuel in the combustion process; and a plurality of sensors positioned to measure one or more variables associated with combustion of the primary fuel in the presence of the secondary fuel. The electronic system is configured to apply a control signal to adjust an engine setting to reduce NOx emissions based in part on the magnitude of the variable.

A low-pressure loop EGR device for an engine with a supercharger, EGR passage, and EGR valve. An ECU controls the EGR valve to fully close, the intake valve to fully open, and the throttle valve to open at a sonic opening degree during deceleration and fuel cut-off. The ECU obtains an actual opening degree of the throttle valve based on the detected intake amount and a predetermined reference formula of valve passing flow rate. The ECU performs correction control of the throttle valve based on a throttle opening degree correction value learned from a difference of the actual opening degree and the predetermined opening degree. The ECU obtains an actual opening degree of the intake valve similarly to the above, and performs correction control of the intake valve based on an intake opening degree correction value learned by the difference between the actual opening degree and the predetermined opening degree.