A method for operating a combustion engine performing an injection quantity correction is described. A total injection quantity per pulse of an injector is divided into a plurality of smaller equal quantity pulses. The smaller quantity pulses are implemented in ballistic injector mode. On the basis of this step, a corresponding offset correction is carried out. After the offset correction has been applied, a further correction is carried out in linear injector mode. An additional alternative for performing an injection quantity correction without additional sensor hardware is thereby provided.

A method for a model-based open-loop and closed-loop control of an internal combustion engine includes the steps of: determining, via a combustion model, injection system setpoint values for controlling injection system actuators, according to a setpoint torque; adapting, during an operation of the internal combustion engine, the combustion model according to a model value, the model value being calculated from a first Gaussian process model for representing a base grid and a second Gaussian process model for representing adaptation data points; determining, by an optimizer, a minimized measure of quality by changing the injection system setpoint values within a prediction horizon, and, in an event that the minimized measure of quality is found, the injection system setpoint values are set as critical for adjusting an operating point of the internal combustion engine; and monitoring the model value in respect of a monotony which is predefined.

An engine test method that causes a computer to execute a process including, acquiring, by a processer on the computer, a first test pattern in which an operation variable that is used for an engine test is changed in time series, inputting, based on the first test pattern, a first operation variable to a mathematical model that represents a time series response of an engine obtained by inputting a test pattern as a simulation of the engine test, monitoring, as a first monitoring parameter of engine abnormality, at least one of an air excess ratio, pressure and temperature of an intake manifold, pressure and temperature of an exhaust manifold, and a maximum cylinder pressure rise rate that are obtained by inputting the first operation variable to the mathematical model, holding, when the first monitoring parameter exceeds a first threshold value, the first operation variable until the first monitoring parameter is less than the first threshold value, creating, a history of the first operation variable in the simulation as a second test pattern, monitoring, as a second monitoring parameter, at least one of the air excess ratio, the pressure and the temperature of the intake manifold, the pressure and the temperature of the exhaust manifold, and the maximum cylinder pressure rise rate that are obtained by inputting a second operation variable to a real engine based on the second test pattern, holding, when the second monitoring parameter exceeds a second threshold value, the second operation variable until the second monitoring parameter is less than the second threshold value, and acquiring, time series data of the second operation variable and a controlled variable.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias.

An engine includes a first injection valve, which is one of port and direct injection valves, and a second injection valve, which is the other. When operating only the first injection valve based on a base injection amount, which has been corrected using a feedback operation amount and a first learning value, an air-fuel ratio control apparatus updates the first learning value and determines that the first learning value has converged on condition that a correction ratio of the base injection amount is not more than a predetermined ratio. When the first and second injection valves are being operated, the apparatus updates a second learning value for the second injection valve on condition that the first learning value has converged and the ratio of the injection amount of the second injection valve is not less than a specified value.

A controller for an internal combustion engine includes a detector and a processor. The detector detects a combustion condition of a gas in a cylinder of the internal combustion engine. The processor is configured to calculate a fuel ratio in the gas in the cylinder. The processor is configured to calculate a target combustion condition according to the fuel ratio. The processor is configured to calculate an ignition timing such that the combustion condition detected by the detector becomes equal to the target combustion condition.

Disclosed is a combustion system design method based on a target heat release rate, which belongs to the technical field of diesel engine combustion chamber design. The method includes: obtaining an ideal heat release rate based on Sabathe-Miller cycle; simulating the ideal heat release rate based on a double-Wiebe function and obtaining the target heat release rate; constructing a mapping relation among the heat release rate, piston geometric parameters and fuel injection parameters, which includes target start of combustion being an function of fuel injection timing and ignition delay, premixed combustion parameters being functions of throat radius, injection pressure and nozzle diameter, and diffusion combustion being a function of piston pit depth; solving target piston geometric parameters and target fuel injection parameters based on the mapping relation; and then designing a combustion system. The method does not depend on experience and multi-scheme design, greatly shortens the combustion system design.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias.

A method determines an inflection point OP of a parameter profile i, n which is representative of a component tolerance and a state of wear of a fuel pump. The fuel pump is provided for a fuel supply system for use in a device equipped with an internal combustion engine. The device being a passenger car, utility vehicle and/or a stationary or mobile power generator.

A control apparatus for an internal combustion engine is configured, during a slightly stratified-charge lean-burn operation, to: calculate a basic total fuel injection amount based on a required torque; calculate a compression stroke injection amount based on an ignition delay index value; calculate, as a basic main injection amount, a value obtained by subtracting a compression stroke injection amount from the basic total fuel injection amount; calculate, based on an output value of an in-cylinder pressure sensor, an actual specified combustion index value that represents a main combustion speed or a combustion fluctuation rate; calculate a main injection correction term based on a result of a comparison between a target specified combustion index value or a tolerable specified combustion index value, and the actual specified combustion index value; and calculate a main injection amount by adding the main injection correction term to the basic main injection amount.