An apparatus for retrieving exhaust heat of an engine, may include the engine including a plurality of combustion chambers, an intake line, an exhaust line, a turbocharger including, a turbine provided on the exhaust line, and a compressor provided on the intake line and compressing external air, an exhaust gas recirculation (EGR) apparatus including an EGR line branched from the exhaust line at a rear end of the turbocharger and merged with the intake line, an EGR cooler disposed on the EGR line, and an EGR valve to adjust an amount of re-circulated exhaust gas, an intercooler to cool the intake gas introduced through the intake line, an intercooler cooling line passing through a radiator and the intercooler, an EGR cooling line passing through the radiator and the EGR cooler, an EGR exhaust line, and an exhaust adjusting valve disposed on the EGR exhaust line.

There is provided a configuration in which a cylinder which is in an inlet stroke when an internal combustion engine is in a stop (automatic stop) state is determined and stored, and when starting the engine upon detection of a start request, the fuel injection of an initial cycle to the cylinder, which has been determined as having been stopped in the inlet stroke when the engine was in the stop state before starting, is split into a plurality if injections at least including an injection before engine rotation, to thereby perform injections. As a result, startability is improved while suppressing pre-ignition at the time of starting.

A diesel engine of the present invention includes a turbocharger including: a turbine provided on an exhaust passage; a compressor provided on an intake passage; and a plurality of nozzle vanes provided around the turbine to control a flow velocity of an exhaust gas colliding with the turbine, angles of the nozzle vanes being changeable. In a case where a ratio of a volume of a combustion chamber when the intake valve is closed to a volume of the combustion chamber when a piston is located at a top dead center is denoted by an effective compression ratio ε.sub.e, and a total displacement of the engine is denoted by V (L), the effective compression ratio ε.sub.e is set to satisfy Formula (1) “−0.67×V+15.2≦ε.sub.e≦14.8.”

A fuel property determination apparatus for an internal combustion engine is applied to an internal combustion engine that is equipped with an ignition plug and an ignition timing controller. An electronic control unit provided in the fuel property determination apparatus executes a determination process of making a determination on a property of a fuel supplied to the internal combustion engine based on an ignition sufficiency ratio, during a predetermined period after startup of the internal combustion engine. The electronic control unit is configured to determine that the property of the fuel is heavy when a determination index value that is obtained by subjecting the ignition sufficiency ratio to a smoothing process is equal to or larger than a predetermined threshold. The electronic control unit is configured to set a smoothing coefficient to a value corresponding to each of a first period, a second period, and a third period.

The invention relates to a control device for an internal combustion engine using the center-of-gravity position of a heat generation rate for combustion control. This control device controls the center-of-gravity position of a heat generation rate to correspond to a reference position in a case where an engine cooling water temperature is equal to or higher than a reference cooling water temperature and controls the center-of-gravity position of a heat generation rate to correspond to a crank angle further on an advance side than the reference position in a case where the engine cooling water temperature is lower than the reference cooling water temperature.

In order to prevent an abnormal combustion due to oil, a restriction region (B) is designated on a low-speed and high-load side of an internal combustion engine (1), and an opening of throttle valve (12) is restricted so that an engine operating condition is not observed within the restriction region (B). A predetermined designated inspection region (A) is set so as to include the restriction region (B), and it is judged whether or not the abnormal combustion actually occurred when the internal combustion engine (1) is running within the designated inspection region (A). If the abnormal combustion was detected, the restriction region (B) is expanded, meanwhile, if the abnormal combustion was not detected, the expanded restriction region (B) is gradually decreased. If the abnormal combustion occurred at a shorter interval than a threshold value, the restriction region (B) is expanded at once to a predetermined size.

A direct fuel injection internal combustion engine having an injector for directly injecting fuel into a combustion chamber thereof is provided. The engine is configured so that a tumble flow is generated in the combustion chamber. A fuel injection by the injector can be performed in a first injection mode and a second injection mode, the first injection mode being a mode in which the fuel injection is completed after the tumble flow is generated, and the second injection mode being a mode in which the fuel injection is completed before the tumble flow is generated. The fuel injection of the first injection mode is performed before completion of the warming-up of the engine, and the fuel injection of the second injection mode is performed after completion of the warming-up of the engine.

A control device that controls an internal combustion engine includes an electronic control unit configured to, during an operation other than a start-up of the internal combustion engine, cause the fuel injection valve to execute one or a plurality of fuel injections in each cycle such that a target fuel injection amount in one injection becomes equal to or greater than a predetermined minimum injection amount, and when the internal combustion engine is started up, in a case where startability of the internal combustion engine is insufficient, execute an excess split injection control for causing the fuel injection valve to execute more fuel injections than the maximum number of fuel injections per cycle while making the target fuel injection amount in one injection smaller than the minimum injection amount per cycle and maintaining a target total fuel injection amount per cycle.

Systems and apparatuses include an aftertreatment system including a catalyst, and a controller coupled to the aftertreatment system. During a warmup period for an engine coupled to the catalyst, the controller is configured to determine a value of a catalyst heating metric indicative of an amount of emissions produced per unit of exhaust energy based on information received from the engine and the aftertreatment system, and control at least one of a turbocharger, a fuel injection system, or an Exhaust Gas Recirculation (EGR) system to reach a target value of the catalyst heating metric.

A fuel injection device for an internal combustion engine including a cylinder, includes a fuel injection valve and a processor. The fuel injection valve injects fuel directly into the cylinder. The fuel injection valve has an injection hole which has a diameter and a length in an axial direction of the injection hole. A ratio of the length to the diameter being 1.0 or smaller. The processor is configured to determine, in a cold operation of the internal combustion engine, a fuel injection time during which the fuel injection valve continues to inject fuel such that an amount of soot in exhaust gas is less than an amount of soot in exhaust gas if the fuel injection valve has the ratio larger than 1.0.