A control device for an internal combustion engine is programmed, during a catalyst warm-up control, to perform first fuel injection by an injector in an intake stroke, control an ignition device so as to generate a discharge spark in a predetermined period in an expansion stroke, and perform second fuel injection, at a timing retarded from a compression top dead center, such that its injection period overlaps with at least a part of the predetermined period and an end timing of the injection period is advanced from an end timing of the predetermined period. Further, the control device is programmed, during the catalyst warm-up control, to control an actual tumble ratio depending on a result of determination using a first index value representing a speed of initial combustion accompanying an ignition by the ignition device and a second index value representing a speed of main combustion accompanying the ignition.

Systems and methods for generating auxiliary torque are provided. In one example, a method for controlling a supercharger comprises, responsive to requested torque exceeding spark authority of an engine, varying a current applied to a motor of the supercharger to provide an amount of torque to a crankshaft of the engine. In this way, a supercharger can be controlled to compensate for an engine torque shortfall.

An intake stroke injection and a compression stroke injection are performed during catalyst warm-up control (upper section in FIG. 7). During the catalyst warm-up control, a discharge period at an electrode portion is set on a retard side of compression top dead center, and an expansion stroke injection is performed during the discharge period. However, when a distance between a spray contour surface and the electrode portion increases, an additional injection (first injection) is performed in advance of the expansion stroke injection (second injection) (lower section in FIG. 7). The additional injection is performed at a timing that is on the retard side of compression top dead center and is on an advance side relative to a start timing of the discharge at the electrode portion.

Provided is a method for diagnosing whether an oxidation catalyst has degraded, based on an output value from one diagnostic sensor with higher accuracy. When a ratio of nitrogen monoxide that is oxidized by a catalyst and discharged downstream of the catalyst as nitrogen dioxide, with respect to nitrogen monoxide contained in an exhaust gas supplied upstream of the catalyst in an exhaust path is defined as a NO conversion rate, a diagnostic sensor configured to output an electromotive force corresponding to the NO conversion rate as a diagnostic output is provided downstream of the catalyst in the exhaust path, and whether the catalyst has degraded beyond an acceptable limit is diagnosed by comparing the diagnostic output with a threshold value predetermined depending on a temperature of the catalyst.

A system and method for modifying the engine pull-up (EPU) logic within a hybrid vehicle based on max motor torque that accounts for the drop or change in available motor torque due to the opening/slipping of a torque converter bypass clutch during engine starts is disclosed. An engine pull-up threshold is determined from max available motor torque at a virtual impeller speed, where the virtual impeller speed is the impeller speed that would result if the torque converter bypass clutch was open/slipping and transferring the same amount of torque.

A control device for an internal combustion engine is provided with a target air-fuel ratio setting part including a first setting control part performing normal control alternately switching a target air-fuel ratio between a predetermined first lean air-fuel ratio and a predetermined first rich air-fuel ratio and a second setting control part performing control for restoration of the storage amount stopping normal control and increasing the oxygen storage amount of a second catalyst when an output air-fuel ratio of a third air-fuel ratio sensor becomes a predetermined rich judgment air-fuel ratio or less. Further, the second setting control part is configured to set the target air-fuel ratio to a predetermined second lean air-fuel ratio larger than the first lean air-fuel ratio at the time of start of the control for restoration of the storage amount and set the target air-fuel ratio to a predetermined third lean air-fuel ratio smaller than the second lean air-fuel ratio after an exhaust with a larger air-fuel ratio than the stoichiometric air-fuel ratio flows out from the first catalyst in the time period of setting the target air-fuel ratio to the second lean air-fuel ratio.

A method to reduce NOx breakthrough and NH3 slip is provided when the SCR system is increasing in temperature and/or increasing exhaust gas mass flow. The method includes the steps of monitoring states of parameters of the exhaust gas upstream of an SCR catalyst where the states of parameters include at least one of the inlet temperature or the exhaust gas mass flow; identifying one of a temperature increase or an increased exhaust gas mass flow at the SCR inlet; identifying a new lower ammonia set-point or storage concentration for the SCR; and identifying the rate of NH3 consumption. The method further includes the step of determining an “intervening phase” a small dosage of DEF is continued during the intervening phase.

A control device is configured to perform, when it is estimated that a combustion fluctuation increases, estimation related to an ignition delay for initial flame generated from a discharge spark and an air-fuel mixture containing fuel spray injected by intake stroke injection. When it is estimated that the ignition delay for the initial flame is increased from that before the increase in the combustion fluctuation, an injection amount in expansion stroke injection is reduced in a next time cycle. When it is estimated that the ignition delay for the initial flame is reduced from that before the increase in the combustion fluctuation, the injection amount in expansion stroke injection is increased in a next time cycle.

Switchable radiative energy harvesting systems and methods of harvesting radiation are disclosed. A system includes an optical filter that includes at least one of an active material and a passive material. The optical filter is switchable between a shield mode and a harvesting mode such that the at least one of the active material and the passive material is in a reflecting state during the shield mode such that the optical filter blocks passage of radiation from a thermal emitter to a thermophotovoltaic cell and a transmitting state during the harvesting mode such that that the optical filter allows the radiation to pass from the thermal emitter to the thermophotovoltaic cell.

A characteristic determining device is provided which determines fuel injection characteristics of a plurality of fuel injectors for an internal combustion engine. The characteristic determining device includes a pressure sensor and a plurality of pipes each of which connects between the pressure sensor and one of the fuel injectors. The pressure sensor is designed to have a plurality of pressure inputs from the respective fuel injectors through the pipes and outputs a signal indicative of a level of pressure in each of the fuel injectors. The characteristic determining device analyzes the signals from the first pressure sensor to determine the fuel injection characteristics of the respective fuel injectors. These arrangements result in a simplified structure of the characteristic determining device and a decreased manufacturing cost thereof.