In a multi-fuel system for diesel engines, natural gas is mixed with diesel fuel and conditioned in a mixing chamber before being injected into the mixing chamber of the engine. Filtered blow-by gas may also be introduced into the combustion chamber. A computerized controller is used to determine and control the proportion of diesel fuel, natural gas fuel, the mixing and conditioning of these fuels, and the supply of filtered blow-by gas.

The purpose of the present invention is to provide an engine with reforming cylinders which are fuel reforming devices capable of supplying a reformed fuel according to the outputs of outputting cylinders. The engine is provided with the outputting cylinders for burning the fuel and the reforming cylinders which are the fuel reforming devices for reforming the fuel through the reciprocating motions of pistons. The amount of reformed fuel supplied to all the outputting cylinders is changed according to the outputs of the outputting cylinders while maintaining the amount of supplied fuel and the amount of suctioned gas, which are supplied into one reforming cylinder.

A method for operating an engine, comprising port injecting a first quantity of a first gaseous fuel in a cylinder cycle and direct injecting a second quantity of a secondary injectant in the cylinder cycle as a function of a desired air-to-fuel ratio (AFR), the desired AFR based on a temperature of an engine cylinder valve. The desired AFR may be outside the AFR range available during natural gas combustion alone and thus allows for cooler engine operation.

Methods and systems are provided for synergizing the benefits of an electric fuel separator in a hybrid vehicle system. A vehicle controller may hold the engine in a narrow operating range where usage of a selected higher octane or lower octane fuel fraction is optimal while using motor and/or CVT adjustments to address transients generated as driver demand varies. The controller may also adjust a fuel separator speed/pressure opportunistically during regenerative braking to maximize electrical usage as well as at low load conditions to enable extended engine operation in a more fuel efficient load region.

Values of at least one energy utilization characteristic, which represents a first energy utilization process in a first vehicle, are determined. Furthermore, values of at least one parameter, which represents at least one boundary condition of the energy utilization in the first vehicle during the first energy utilization process, are also determined. A mathematical relationship between at least one or more values provided for the at least one energy utilization characteristic and the corresponding values of the parameters is determined and a profile record comprising a record and/or learning data is provided on the basis of at least one mathematical relationship determined. Depending on the profile record, at least one operating parameter of the drive system of the first vehicle and/or of a second vehicle is adapted in a second energy utilization process.

A secondary fuel injection system determines (precisely) a maximum amount of secondary fuel that can be injected into a cylinder during a cycle based upon the rotational speed (RPM) of the engine. A primary fuel injection pulse width of the prior cycle and is used to determine how much heat energy was requested by an engine control module based upon the duration of the injection pulse. Secondary fuel is injected into the intake port of the cylinder after the exhaust valve closes in an amount that is calculated based upon the maximum that can be injected during the allowed calculated time of crankshaft rotation and the amount of heat energy requested in the prior cycle and to include the amount of primary fuel that is then injected into the cylinder is being reduced based upon the amount of heat energy provided by the secondary fuel that was previously injected.

A control device for an internal-combustion engine to utilize low octane fuel and high octane fuel having a high octane value higher than a low octane value of the low octane fuel, the control device includes an inclination state sensor and a computer processor. The inclination state sensor detects an inclination state of a high octane fuel tank to store the high octane fuel. The computer processor acquires a remaining quantity of the high octane fuel in the high octane fuel tank. The computer processor restricts a power generated by the internal-combustion engine in accordance with the inclination state and the remaining quantity.

A control apparatus for an internal combustion engine, includes circuitry. The circuitry is configured to control a ratio of an amount of low octane number fuel to be supplied to a cylinder to a total amount of the low octane number fuel and a high octane number fuel to be supplied to the cylinder in order to control an overall octane number of fuel to be supplied to the cylinder. The high octane number fuel has a second octane number higher than a first octane number of the low octane number fuel. The circuitry is configured to calculate a maximum octane number of the fuel to be supplied into the cylinder. The circuitry is configured to restrict a power generated by the internal combustion engine based on the maximum octane number.

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.

Systems, methods and apparatus for controlling operation of dual fuel engines are disclosed that regulate the fuelling amounts provided by a first fuel and a second fuel during operation of the engine. The first fuel can be a liquid fuel and the second fuel can be a gaseous fuel. The fuelling amounts are controlled to improve operational outcomes of the duel fuel engine.