Abstract: An operating mode for an internal combustion engine, in particular a directly injected internal combustion engine having a plurality of combustion chambers, in particular for a directly injected gasoline engine, e.g. for a motor vehicle, having low NOx combustion (NAV). During the NAV operating mode that is the subject matter of this invention, at an ignition point (ZZP) a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 in the respective combustion chamber is spark ignited by an ignition device, whereby the flame front combustion initiated by the ignition device (FFV) transitions to a controlled auto-ignition (RZV). The NAV operating mode enables a controlled auto-ignition to be performed in an engine load range in which a pure RZV operating mode is no longer stable enough to be implemented.

Abstract: A method for operating a hybrid drive train involves operating an internal combustion engine using a low-NOx operating method in a range of low and average rotational speeds and/or loads, and operating the internal combustion engine using a spark ignition operating method in a range of higher rotational speeds and/or loads.

Abstract: A method for operating a hybrid drive train involves operating an internal combustion engine using a low-NOx operating method in a range of low and average rotational speeds and/or loads, and operating the internal combustion engine using a spark ignition operating method in a range of higher rotational speeds and/or loads.

Abstract: An operating mode of an internal combustion engine, in particular a directly injected internal combustion engine featuring a plurality of combustion chambers, in particular for a direct-injection gasoline engine for a motor vehicle, an operating mode having at least in part low-NOx combustion (NAV) and having a plurality of partial operating modes wherein it is switched between another partial operating mode and a NAV partial operating mode, wherein in the case of said NAV partial operating mode, at an ignition point (ZZP) a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 is spark ignited in the respective combustion chamber by means of an ignition device, and where a flame front combustion (FFV) initiated by the spark-ignition transitions to a controlled auto-ignition (RZV). The operational stability of the respective partial operating mode can be improved by variation of the compression ratio ?.

Abstract: In an operating method for an internal combustion engine with direct fuel injection including a plurality of combustion chambers, in particular a direct-injection gasoline engine for a motor vehicle, wherein the operating method comprises low-NOx combustion (NAV) and uses a plurality of partial operating modes, wherein, in a NAV partial operating mode, water is injected into the respective combustion chamber, and, during said NAV partial operating mode, at an ignition point (ZZP), a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 is spark ignited by means of an ignition device so as to initiate flame front combustion (FFV) with a transition to a controlled auto-ignition (RZV). The injection of water permits the NAV partial operating mode to be stably implemented even at high engine loads and speeds.

Abstract: An operating mode for an internal combustion engine, in particular a directly injected internal combustion engine having a plurality of combustion chambers, in particular for a directly injected gasoline engine, e.g. for a motor vehicle, having low NOx combustion (NAV). During the NAV operating mode that is the subject matter of this invention, at an ignition point (ZZP) a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 in the respective combustion chamber is spark ignited by an ignition device, whereby the flame front combustion initiated by the ignition device (FFV) transitions to a controlled auto-ignition (RZV). The NAV operating mode enables a controlled auto-ignition to be performed in an engine load range in which a pure RZV operating mode is no longer stable enough to be implemented.

Abstract: In order to control an internal combustion engine according to the invention, a polytropic exponent is determined in accordance with at least two measured values of the pressure in the combustion chamber of the cylinder, said measured values being detected after closing the gas discharge valve and before successively opening the gas intake valve. An exhaust gas mass which is located in the cylinder after closing the gas discharge valve and before successively opening the gas intake valve is determined according to the polytropic exponent at an estimated value of the pressure after closing the gas discharge valve and before successively opening the gas intake valve as well as at a certain temperature of the exhaust gas located in the cylinder after closing the gas discharge valve and before successively opening the gas intake valve. An actuation signal for controlling an actuating member of the internal combustion engine is generated in accordance with the determined exhaust gas mass.

Abstract: The invention is directed toward a device for controlling an internal combustion engine. An aspect of the invention is determining a polytropic exponent according to at least two measured values of the pressure in a combustion chamber of a cylinder of an internal combustion engine during the working stroke of the cylinder once an air/fuel mixture of a cylinder has been burned and before the gas discharge valve is opened. A first exhaust gas temperature is determined and a second temperature of the exhaust gas is determined in accordance with the first exhaust gas temperature. The pressure associated in the combustion chamber, the pressure prevailing in the combustion chamber after closing the gas discharge valve, and the polytropic exponent are determined. An actuation signal for controlling an actuating member of the internal combustion engine is generated according to the second temperature of the exhaust gas.

Abstract: In a method of operating an internal combustion engine with a switch-over capability between a compression ignition mode of operation and a spark ignition mode of operation in higher load ranges which includes a cam-operated valve drive with a valve control providing, in the compression ignition mode of operation, for an increased valve overlap of the valve opening times, smooth engine operation and optimal exhaust gas emissions are obtained also during rapid load changes upon changing the engine operating mode as the change-over is accompanied by changes of the injection parameters, the throttling parameter and the valve control, which are coordinated with respect to one another as the valve control is switched over by changing the amplitude and phase position of the valve stroke of at least one of the inlet and outlet valves.

Abstract: A method for operating a four stroke internal combustion engine in which the combustion position can be set/controlled/corrected. The phase position of intake and/or exhaust phase is shifted for this purpose. Compression ignition takes place at part-load, and spark ignition takes place at full load. In the event of a load change in the part-lead range, the theoretical shift in the combustion position is compensated by the shift in phase position of the intake and/or exhaust phase.

Abstract: Disclosed is a method for operating an internal combustion engine, wherein fuel is injected in a pre-injection and main injection process. According to the invention, pre-injection occurs in the intermediate compression stroke of the internal combustion engine. Main injection is carried out in an intake synchronous manner. The invention can be used for internal combustion engines, particularly for passenger cars and commercial vehicles.

Abstract: In a method for operating an internal combustion engine in which the angular locations where the fuel/air mix combustions takes place can be controlled by an adjustment of the inlet and outlet valve timing, the timing of at least one of the intake and exhaust valve opening phases is shifted depending on the engine speed so as to reduce engine emissions.

Abstract: In a method for operating an internal combustion engine having a variable compression ratio either in a compression ignition or in a spark ignition operating mode depending on the engine operating point, a higher compression ratio is provided in the compression ignition mode than in the spark ignition mode so as to optimize the operation of the internal combustion engine at low and medium engine loads, and to reduce engine emissions.

Abstract: In a method of operating a reciprocating-piston internal combustion engine with a combustion chamber in which a fuel mix with fresh gas is provided via intake ports and combustion exhaust gases are discharged through exhaust ports which can be opened by intake valves and, respectively, exhaust valves which are actuated by a valve operating mechanism, wherein an operating mode with external ignition, in which the fuel mix is ignited by a spark plug, is provided in part of the load range of the internal combustion engine, and an operating mode with compression ignition, in which the control of the gas exchange valves is altered so as to retain combustion exhaust gases in the combustion chamber for participation in the formation of the fresh mix is provided in another load range of the internal combustion engine, during a change in the operating mode the valve lift of at least one of the gas exchange valves is altered.

Abstract: A method retains exhaust gas in the combustion chamber of an internal combustion engine and compresses the exhaust gas during a charge change. A first fuel quantity is injected into the retained exhaust gas by direct fuel injection. A second fuel quantity is subsequently fed to the combustion chamber so that a homogeneous fuel/air mixture is obtained in the combustion chamber. An auto-ignition time of the fuel/air mixture which is formed from the first and second fuel quantities is set as a function of a quantity ratio of the first fuel quantity to the second fuel quantity.

Abstract: In a method for operating an internal combustion engine in which the fuel is injected into a combustion chamber of a pre-injection and a main injection quantity, the quantity of fuel for the pre-injection, which is selected depending on the combustion location, is injected before the top dead center of the gas exchange, and the fuel for the main injection is injected synchronously with the induction of the air. The method is used in connection with internal combustion engines, in particular for passenger and commercial motor vehicles.

Abstract: 1. Method for operating an internal combustion engine 2.1. The invention proposes a method for operating an internal combustion engine in which the combustion position can be set/controlled/corrected. 2.2. According to the invention, it is provided that the phase position of intake and/or exhaust phase is shifted for this purpose. 2.3. Use for internal combustion engines, in particular for passenger and commercial motor vehicles.

Abstract: A method retains exhaust gas in the combustion chamber of an internal combustion engine and compresses the exhaust gas during a charge change. A first fuel quantity is injected into the retained exhaust gas by direct fuel injection. A second fuel quantity is subsequently fed to the combustion chamber so that a homogeneous fuel/air mixture is obtained in the combustion chamber. An auto-ignition time of the fuel/air mixture which is formed from the first and second fuel quantities is set as a function of a quantity ratio of the first fuel quantity to the second fuel quantity.

Abstract: In a method of operating a supercharged internal combustion engine in which exhaust gas is retained in the combustion chamber during a charge change, wherein the engine is operated with compression ignition or with spark ignition depending on the operating point and in which a charge pressure can be established for the fresh air supplied to the combustion chamber, and the exhaust gas is compressed during the charge change, and a first fuel quantity is optionally injected into the retained exhaust gas and a second fuel quantity is subsequently supplied to the combustion chamber, such that a homogeneous fuel/air mixture is formed in the combustion chamber, the retained exhaust gas quantity in the combustion chamber is corrected in such a way that the center of the combustion is displaced in the direction toward a set point value when the center of the combustion deviates from the set point value because of a change in the charge pressure of the fresh air or because of a change in the temperature of the fresh ai

Abstract: Disclosed is a method for operating an internal combustion engine, wherein fuel is injected in a pre-injection and main injection process. According to the invention, pre-injection occurs in the intermediate compression stroke of the internal combustion engine. Main injection is carried out in an intake synchronous manner. The invention can be used for internal combustion engines, particularly for passenger cars and commercial vehicles.