An estimation device that is applicable to a combustion system including 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 the fuel used for combustion in the internal combustion engine. The combustion amount estimation unit estimates a combustion amount of the fuel caused by a pilot combustion produced by injecting the fuel into a combustion chamber of the internal combustion engine with a pilot injection, based on the mixing ratio acquired by the mixing acquisition unit. The region estimation unit estimates a combustion region of the pilot combustion in the combustion chamber based on the mixing ratio. The timing estimation unit estimates an ignition timing, at which an ignition occurs in the combustion chamber with the pilot injection, based on the mixing ratio.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

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.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

A method for operating an internal combustion engine with detection of the fuel used for injection is described. In the method, the elasticity modulus of the fuel to be injected is determined at a first and a second injection pressure. A difference value is calculated from the difference between the two elasticity modulus values related to the pressure difference and is compared with a differentiating value. The fuel being used is detected depending on whether the difference value is above or below the differentiation value. In particular, the method is used for differentiating diesel fuel EN590 and biodiesel.

Methods and systems are provided for an integrated fuel composition-pressure sensor. In one example, the integrated sensor may include a set of cylindrical capacitors and a set of plate capacitors with a common capacitor element shared between the sets. A composition of fuel may be determined from the set of cylindrical capacitors and a pressure of fuel may be determined from the set of plate capacitors.

A method of determining the cetane number of a fuel in an internal combustion engine comprising, during running of the engine, i) with respect to one cylinder, performing a routine including a series of injections such that for each injection a quantity of fuel is injected into the cylinder, and during the routine varying the angle at which the injections takes place with respect to crankshaft angle; ii) measuring engine speed at intervals during the series of injections and determining values for changes in engine speed consequent to the injections; iii) determining cetane number from a pre-stored relationship relating the cetane number to changes in engine speed consequent to changes in the test injection angle.

This fuel property estimation device is used in an internal combustion engine that uses a mixed fuel of three kinds of fuel and includes a first sensor that outputs a signal responsive to a physical property of the fuel in a fuel route and a second sensor outputs a signal responsive to an oxygen concentration of exhaust gas. This device measures a physical property value of the mixed fuel based on a first sensor signal, and calculates an air-fuel ratio value at stoichiometric combustion state using feedback of a second sensor signal. This device estimates a composition ratio of the mixed fuel based on the measured physical property value and the calculated air-fuel ratio value by referring to a relationship between the composition ratio of the mixed fuel and the physical property value and a relationship between the composition ratio of the mixed fuel and a theoretical air-fuel ratio value.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.