An object of the invention is to reduce the amount of smoke generated and to improve the stability of diesel combustion in cases where an EGR apparatus is used in an internal combustion engine that performs diesel combustion using fuel having a relatively high self-ignition temperature. A control apparatus performs first injection at a first injection time during the compression stroke, causes spray guide combustion to occur, and starts to perform second injection at such a second injection time that causes combustion of injected fuel to be started by flame generated by the spray guide combustion, thereby causing self-ignition and diffusion combustion of fuel to occur. The apparatus changes the ratio of the first injected fuel quantity to the total fuel injection quantity and the ratio of the second injected fuel quantity to the total fuel injection quantity for the same total fuel injection quantity in one combustion cycle, based on the EGR rate in the intake air.

A control device for an internal combustion engine includes an electronic control unit. The electronic control unit is configured to control an injection amount and an injection timing of fuel to a target injection amount and a target injection timing set based on an engine operation state, detect an ignition timing of fuel based on a vibration component of an engine body in a specific frequency bandwidth, and correct at least one of the target injection amount and the target injection timing based on a deviation between the detected ignition timing and a target ignition timing according to the engine operation state. The specific frequency bandwidth is a bandwidth on a low frequency side of a frequency bandwidth where the engine body undergoes elastic vibration.

A method and system for controlling operation of an internal combustion engine of a vehicle (such as a remotely operable unmanned aerial vehicle) to perform or implement a control strategy for controlling operation of the engine. The method and system comprises providing first and second modes optionally available for operating the engine, and changing operation of the engine from the first mode of operation to the second mode of operation following a determination that a characteristic of the operation of the engine (such as engine speed) has been requested to be modified to beyond a predetermined threshold or level. The method and system further comprises reverting control of operation of the engine from the second mode to the first mode once the requested characteristic is no longer beyond the predetermined threshold or level.

Methods and systems for accurate and precise fuel supply control for continuous-flow of gaseous fuel to an internal combustion engine over a large dynamic power range, including a dual-stage valve that allows optimal controla first stage in the form of a voice-coil driven electronic pressure regulator, and a second stage in the form of a voice-coil-driven choked-flow valve; monitoring the pressure of the fuel intermediate the two stages and making appropriate adjustments to the first stage via a pressure actuator loop; feeding the gaseous fuel mixture through a unitary block assembly into the second stage; monitoring the pressure of the air/fuel mixture and making appropriate adjustments to the second stage via a valve actuator control loop.

A engine control device includes an variable exhaust valve mechanism 72 which varies an opening and closing timing of an exhaust valve 22, and a PCM 10 which controls the variable exhaust valve mechanism 72 such that the opening and closing timing of the exhaust valve 22 is varied, wherein the variable exhaust valve mechanism 72 is configured such that a lift amount of the exhaust valve 22 becomes smaller as a retarded degree of the valve opening timing increases, and the PCM 10 is configured to set a maximum retarded valve opening timing in an exhaust stroke based on the lift amount at an exhaust top dead center, and to control the variable exhaust valve mechanism 72 so as to open the exhaust valve 22 in advance of the maximum retarded valve opening timing.

Various embodiments may include a method for setting injection timing for injection of a fuel into a combustion chamber of a cylinder of an internal combustion engine including: determining a torque; determining a speed; determining a cylinder wall temperature; selecting the injection timing based at least on the cylinder wall temperature, the torque, and the speed; and controlling an injection of fuel into the combustion chamber using the selected injection timing.

A compression-ignition low octane gasoline engine. The engine uses low octane gasoline and a compression-ignition method, does not require a spark plug, and compared with ordinary gasoline engines, increases thermal efficiency by approximately 40% and reduces green-house effects caused by emissions by approximately 45%. The compression-ignition of the low octane gasoline engine is a diffusion charge compression-ignition, differing from a homogeneous charge compression-ignition. The compression ratio in a cylinder can be 14 to 22, while an ordinary gasoline engine has a compression ratio of 7 to 11. The low octane gasoline engine has a simple structure, easy combustion control, a low noise level, and a low failure rate. As the low octane gasoline can be free of aromatic hydrocarbons, and not require the addition of antiknock agents such as MTBE and MMT, the present novel gasoline engine is a highly efficient, clean, and environmentally friendly internal combustion engine.

Methods and systems for accurate and precise fuel supply control for continuous-flow of gaseous fuel to an internal combustion engine over a large dynamic power range, including a dual-stage valve that allows optimal controla first stage in the form of a voice-coil driven electronic pressure regulator, and a second stage in the form of a voice-coil-driven choked-flow valve; monitoring the pressure of the fuel intermediate the two stages and making appropriate adjustments to the first stage via a pressure actuator loop; feeding the gaseous fuel mixture through a unitary block assembly into the second stage; monitoring the pressure of the air/fuel mixture and making appropriate adjustments to the second stage via a valve actuator control loop.

Methods and systems are provided for estimating an engine exhaust pressure based on outputs from an exhaust oxygen sensor. In one example, a method may include estimating an exhaust pressure of exhaust gas flowing through an engine exhaust passage based on a difference between a first output of an oxygen sensor disposed in the exhaust passage and a second output of the oxygen sensor and then adjusting engine operation based on the estimated exhaust pressure. As one example, both the first and second outputs may be taken while operating the sensor in a variable voltage mode, after increasing a reference voltage of the oxygen sensor from a lower, first voltage to a higher, second voltage.

Methods and systems for accurate and precise fuel supply control for continuous-flow of gaseous fuel to an internal combustion engine over a large dynamic power range, including a dual-stage valve that allows optimal controla first stage in the form of a voice-coil driven electronic pressure regulator, and a second stage in the form of a voice-coil-driven choked-flow valve; monitoring the pressure of the fuel intermediate the two stages and making appropriate adjustments to the first stage via a pressure actuator loop; feeding the gaseous fuel mixture through a unitary block assembly into the second stage; monitoring the pressure of the air/fuel mixture and making appropriate adjustments to the second stage via a valve actuator control loop.