A fuel content detection system is disclosed. The fuel content detection system may include an engine control module (ECM) to receive a measurement of a parameter. The parameter may correlate with an amount of a substance in a fuel that is being consumed in an engine. The ECM may determine an estimation of the parameter based on a model. The model may use a predetermined value associated with the amount of the substance, and the engine may be configured to consume a designated type of fuel that includes an amount of the substance that corresponds to the predetermined value. The ECM may determine, based on the estimation and the measurement not being within a threshold range, that the fuel is not the designated type of fuel and perform an action associated with the engine.

In certain embodiments, a method and an apparatus which can be implemented with a simplified and inexpensive configuration without causing a misfire in a combustion state. In a fuel-Cetane-number estimation method according to embodiments, a map which specifies a relationship between the Cetane number and a control parameter at which NOx concentration of exhaust gas reaches a predetermined value is prepared in advance. Then, the control parameter is controlled variably to detect transition of the NOx concentration of the exhaust gas of the internal combustion engine, and thereby the control parameter of the internal combustion engine at which the NOx concentration has reached the predetermined value is obtained, and the Cetane number which corresponds to the obtained control parameter is estimated on the basis of the map.

The present disclosure provides a method for predicting a fluid type, comprising sensing, by a first sensor, mass flow data of a fluid in an engine, wherein the first sensor operates based on a first fluid property; sensing, by a second sensor, mass flow data of the fluid, wherein the second sensor operates based on a second fluid property; and detecting, by a logic circuit of a controller, a percent difference in the mass flow data provided by the first and second sensors, the percent difference indicating that the fluid is comprised of at least a first fluid type.

A method for controlling a dual fuel engine system includes determining a gas flow target for an internal combustion engine of the dual fuel engine system, where the gas flow target is based on a gas power target of the internal combustion engine, a thermal efficiency estimate of the internal combustion engine, and a lower heating value (LHV) within the internal combustion engine. The method also includes adjusting the gas flow target based on at least one of a measured gas temperature or a measured gas injector pressure and determining at least one base gas injector command based on the adjusted gas flow target, a gas substitution rate estimate, and a gas substitution rate target. The method further includes determining, based on the at least one base gas injector command, a gas injector command for at least one engine bank.

A control method of an internal combustion engine and an internal combustion engine applying the same. Each cylinder is provided with a throttle valve, or a plurality of paralleled throttle valves are employed to supply air for different cylinders or cylinder groups, so that different cylinders are provided with different inlet pressure and inlet airflow, different spark ignition timing (phase angle), different injection timing (phase angle), and different injection quantity, and in a complete work cycle, some cylinders of the engine operate under a compression ignition combustion mode, and some cylinders of the engine operate under a spark ignition combustion mode. When the conditions for compression ignition combustion mode are satisfied, the cylinders adopt the compression ignition combustion mode as much as possible, so as to improve the thermal power efficiency of the engine. The internal combustion engine or vehicle installed with the control method has wide adaptability to different fuel with different ignition points, can detect the octane number of gasoline, and consume various octane number gasoline.

A method for operating an internal combustion engine with multiple cylinders. Each cylinder of the internal combustion engine includes at least one fuel injector, and each fuel injector is activated for opening and closing via a solenoid valve of the respective fuel injector. Structure-borne sound waves emitted by the fuel injectors and/or accelerations caused by the fuel injectors are detected by measurement. The structure-borne sound waves detected by measurement and/or the accelerations detected by measurement are evaluated, and based on the evaluation, characteristics of the fuel injectors are automatically determined.

A dual fuel engine system, such as for diesel and natural gas operation, includes a control system having an electronic control unit structured to vary a stored control valve for a fuel delivery parameter, responsive to engine power output. The engine power output can be determined by in-cylinder pressure monitoring during a liquid fuel mode. The stored control value can be a dynamically updated value in an engine fueling map.

An estimation device applicable to a combustion system having an internal combustion engine includes a mixing acquisition unit, a combustion amount estimation unit, a region estimation unit, and a timing estimation unit. The mixing acquisition unit acquires a mixing ratio of various components contained in fuel used for combustion in the internal combustion engine. The combustion amount estimation unit estimates a combustion amount of fuel caused by a post combustion generated by injecting fuel into a combustion chamber of the internal combustion engine by post injection, based on the mixing ratio acquired by the mixing acquisition unit. The region estimation unit estimates a combustion region of the post combustion in the combustion chamber based on the mixing ratio. The timing estimation unit estimates an ignition timing at which ignition occurs in the combustion chamber by the post injection based on the mixing ratio.

An example method for operating an internal combustion engine may include: measuring pressure oscillations for a cylinder in the inlet tract at a defined operating point during normal operation; generating a corresponding oscillation signal; determining a crankshaft phase angle corresponding to the oscillation signal; and from the pressure oscillation signal, using discrete Fourier transformation to calculate the actual phase position of a selected signal frequency; determining a further comparison phase position in the same way from the selected signal frequency in the absence of fuel injection; calculating an actual phase position difference; on the basis of the difference, taking into consideration reference phase position differences of the same signal frequency for different fuel compositions, to identify a fuel composition of the presently used fuel; and adapting operating parameters of the engine based on the identified composition.

A controller includes a valve control unit and a target calculation unit. The valve control unit is configured to control a fuel injection valve such that divergence decreases between an ignition delay of fuel injected into a cylinder through main injection and an ignition delay target value. The target calculation unit is configured to calculate the ignition delay target value such that the ignition delay target value decreases as estimated ignitability of the fuel in the cylinder increases during an engine operation in a region where diffusion combustion and premix combustion are both performed, the ignitability of the fuel in the cylinder being estimated based on a parameter that varies the ignitability.