摘要:
A first combustion mode in which an amount of an EGR gas within a combustion chamber is higher than that of the EGR gas when a generated amount of soot reaches a peak and substantially no soot is generated. A second combustion mode in which the amount of the EGR gas within the combustion chamber is lower than that of the EGR gas when the generated amount of soot reaches the peak are selectively performed. A catalyst is disposed within an engine exhaust passage wherein a temperature of the catalyst is adjusted so as to be within a predetermined range.
摘要:
An engine where first combustion where the amount of the EGR gas in the combustion chamber is larger than the amount of EGR where the amount of production of soot peaks and almost no soot is produced and a second combustion where the amount of EGR gas in the combustion chamber (5) is smaller than the amount of EGR gas where the amount of production of soot peaks are selectively switched between. When switching between the first combustion and second combustion, the injection timing is delayed until after top dead center of the compression stroke,
摘要:
A stable combustion without generating smoke or misfire is performed by selectively conducting a first combustion mode and a second combustion mode. In the first combustion mode, an amount of an inert gas, e.g., EGR gas, provided to a combustion chamber is made to be larger than an amount of the inert gas that causes the generation amount of soot to become a peak amount. This causes substantially no soot to be generated. In the second combustion mode, the amount of the inert gas provided to the combustion chamber is made to be smaller than the amount that causes the generation amount of soot to become a peak amount. The injection timing is quickened if the injection amount is increased in the first combustion mode, and the injection timing is delayed if the injection amount is reduced.
摘要:
An internal combustion engine that selectively switches from a first combustion in which an amount of an exhaust gas recirculation gas within a combustion chamber is more than the amount of the exhaust gas recirculation gas when an amount of soot generated reaches a peak amount to generate substantially no soot, that is, a low temperature combustion, and a second combustion in which the amount of the exhaust gas recirculation gas within the combustion chamber is less than the amount of the exhaust gas recirculation gas when the amount of soot generated reaches the peak amount. The switching is selectively performed, such that, a stable low temperature combustion corresponding to the air fuel ratio is performed by shifting the area for performing the low temperature combustion to the high load side as the air fuel ratio is reduced.
摘要:
An internal combustion engine system is capable of reducing soot and NOx simultaneously, and prevents the occurrence of an undesirable situation where a generation amount of soot is increased in accordance with frequent transitions between a first combustion mode and a second combustion mode. In the system, the first combustion mode in which an amount of inert gas supplied to the combustion chamber is larger than an amount of the inert gas that causes the generation amount of soot to become a peak, such that soot is hardly generated, and a second combustion mode in which an amount of the inert gas supplied to the combustion chamber is smaller than the amount of the inert gas that causes the generation amount of soot to become a peak, are selectively performed. When conditions are such that switching between the first combustion mode and the second combustion mode has or may occur frequently, the execution of the first combustion mode is controlled. The frequency of switching can be determined, for example, based on a frequency of change of the engine load, an operational state of the engine, or road information.
摘要:
An internal combustion engine performs a second mode of combustion where the EGR is less than the EGR gas that peaks the production of soot. The engine then performs a first mode of combustion where the EGR is greater than the EGR that peaks the production of soot. During the second mode, the engine curbs hydrocarbon supplied to an exhaust gas control catalyst by performing a combustion where hydrocarbon does not increase. The exhaust gas temperature discharged becomes relatively high and the EGR rate is set to zero. The engine then increases the hydrocarbon supplied to the catalyst by performing a combustion that increases the hydrocarbon. The temperature of exhaust gas discharged becomes relatively high, and the EGR rate is gradually increased. Accordingly, the engine quickly warms up the catalyst while preventing problems that occur, like clogging of an exhaust gas recirculation passage.
摘要:
An internal combustion engine has an EGR passage provided with an EGR control valve and a catalyst for purifying the EGR gas. When the internal combustion engine operates in a low-temperature combustion mode in which the amount of EGR gas supplied to a combustion chamber is larger than that of EGR gas with which the amount of soot produced reaches a peak, and almost no soot is produced, a controller reduces an opening amount of the exhaust gas recirculation control valve so as to increase an exhaust gas temperature, and reduces an opening amount of the throttle valve so as to suppress an increase in the amount of the EGR gas, thereby to reduce reductions in the temperature of the EGR gas and the temperature of the catalyst.
摘要:
An engine where first combustion where the amount of the EGR gas in the combustion chamber is larger than the amount of EGR where the amount of production of soot peaks and a second combustion where the amount of EGR gas in the combustion chamber is smaller than the amount of EGR gas where the amount of production of soot peaks are selectively switched between and where an NOx absorbent is placed in the exhaust passage of the engine. When SOx should be released from the NOx absorbent, the first combustion is performed under a rich air-fuel ratio, while when the second combustion is performed, auxiliary fuel is injected during the first part of the suction stroke or the expansion stroke and the injection timing of the main fuel is delayed by a large extent.
摘要:
Cylinders of a diesel engine 1 are provided with cylinder pressure sensors 29a to 29d for detecting combustion chamber pressures. An electronic control unit (ECU) 20 of the engine selects optimum combustion parameters in accordance with a fuel injection mode of fuel injectors 10a to 10d of the engine and a combustion mode determined by the amount of EGR gas supplied from the EGR valve 35 from among a plurality of types of combustion parameters expressing the combustion state of the engine calculated based on the cylinder pressure sensor output and feedback controls the fuel injection amount and fuel injection timing so that the values of the combustion parameters match target values determined in accordance with the engine operating conditions. Due to this, the engine combustion state is controlled to the optimum state at all times regardless of the fuel injection mode or combustion mode.
摘要:
Cylinders of a diesel engine 1 are provided with cylinder pressure sensors 29a to 29d for detecting combustion chamber pressures. An electronic control unit (ECU) 20 of the engine selects optimum combustion parameters in accordance with a fuel injection mode of fuel injectors 10a to 10d of the engine and a combustion mode determined by the amount of EGR gas supplied from the EGR valve 35 from among a plurality of types of combustion parameters expressing the combustion state of the engine calculated based on the cylinder pressure sensor output and feedback controls the fuel injection amount and fuel injection timing so that the values of the combustion parameters match target values determined in accordance with the engine operating conditions. Due to this, the engine combustion state is controlled to the optimum state at all times regardless of the fuel injection mode or combustion mode.