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 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 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:
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 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, a control operation is provided for the combustion process, wherein an actual value of the crank angle of a 50% mass conversion point of the fuel to be converted during the combustion is determined taking into account a measurement signal of an ion current sensor which is arranged in a combustion chamber, and the crank angle of the 50% mass conversion point is adjusted to a set point value of the position of the 50% mass conversion point by varying at least one manipulated variable of the internal combustion engine which affects the combustion. The crank angle of the 50% mass conversion point is determined in a layered neural network in which the measurement results of the ion current sensor are logically combined with at least one further, continuously measured operating parameter of the internal combustion engine.
Abstract:
In a method for adapting a torque model for operating an internal combustion engine, which torque model indicates an ignition angle adjustment as a function of an air charge in a cylinder of the internal combustion engine, the torque model is adapted based on a variation of an operating variable of the internal combustion engine caused by a mode switching.
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 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.