An internal combustion engine includes a fuel injection nozzle provided with a nozzle hole for injecting fuel, the nozzle hole exposed from a cylinder head of the internal combustion engine to a combustion chamber, and a hollow duct, an inlet and an outlet of which are exposed to the combustion chamber. The duct is provided in a manner allowing fuel spray injected from the nozzle hole of the fuel injection nozzle to pass through from the inlet to the outlet. The fuel injection nozzle and the duct are configured such that a part of fuel spray that is injected in pilot injection that is performed before main injection directly adheres to an inner wall surface of the duct.

The control apparatus for a compression ignition type engine includes a plurality of cylinder inner pressure sensors that detect pressure in each cylinder, and a combustion control unit. The combustion control unit corrects a target fuel injection amount of each cylinder by an injector based on a deviation between a predicted combustion period that is a period from an ignition timing by an ignition plug to a predetermined mass combustion timing and that is obtained based on a preset combustion model, and an actual combustion period that is a period from the ignition timing by the ignition plug to an actual combustion timing and that is obtained based on cylinder inner pressure, such that the period from the ignition timing by the ignition plug to the predetermined mass combustion timing, which is the timing when fuel having a predetermined mass ratio combusts, is equalized in each cylinder.

A method of controlling combustion in an internal combustion engine includes measuring parameters of combustion in a cylinder of the engine during a combustion phase of the cylinder, after igniting an air/fuel charge in the cylinder, and calculating the heat release of combustion in the cylinder based on the measured parameters. An auto-ignition event of the air/fuel charge is identified based on the calculated heat release, and, based at least in part on the identified auto-ignition event, at least one of ignition timing in the cylinder for the next combustion phase of the cylinder or an amount of exhaust gas supplied to the cylinder for the next combustion phase of the cylinder is controlled to cause an auto-ignition event of the air/fuel charge in the next combustion phase to shift toward a specified crank angle.

A control device for a compression-ignition engine in which partial compression-ignition combustion including spark ignition (SI) combustion performed by combusting a portion of a mixture gas inside a cylinder by spark-ignition followed by compression ignition (CI) combustion performed by causing the remaining mixture gas to self-ignite is executed at least within a part of an engine operating range is provided, which includes a detector configured to detect a given parameter that changes as combustion progresses inside the cylinder, an A/F (air-fuel ratio) controller configured to change an air-fuel ratio of air to fuel introduced into the cylinder, and a combustion controller configured to determine combustion stability based on the detected parameter of the detector and control the A/F controller to reduce the air-fuel ratio when it is confirmed that during the partial compression-ignition combustion the combustion stability is low.

A method to control the combustion of an internal combustion engine comprising determining a combustion model providing a spark advance value depending on an objective value of a quantity representing the incidence of a low-pressure EGR circuit, of the rotation speed, of the intake efficiency and of an open-loop contribution of a combustion index; calculating a first closed-loop contribution of the spark advance depending on the combustion index; calculating a second closed-loop contribution of the spark advance depending on a quantity indicating the knocking energy; and calculating the objective value of the spark advance angle to be operated through the sum of the spark advance value provided by the combustion model and of the first closed-loop contribution or, alternatively, of the second closed-loop contribution.

Methods and systems for operating an engine responsive to filtered cylinder pressure data are disclosed. In one example, fuel injection timing may be advanced in response to filtered cylinder pressure data that is indicative of onset of combustion in a cylinder being delayed from an expected timing. The filtered cylinder pressure data may be generated via a digital filter.

A method for estimating a peak cylinder pressure associated with operation of an internal combustion engine may include receiving, in a cylinder combustion model, a fuel signal and an air signal. The cylinder combustion model may be configured to estimate at a first crankshaft angle, a first mass fuel burn rate and a first burned fuel-air ratio associated with combustion. The cylinder combustion model may also be configured to estimate at a second crankshaft angle, a combustion ignition delay associated with the combustion, and estimate at the second crankshaft angle, a start of combustion associated with the combustion of the fuel and the air supplied to the cylinder. The cylinder combustion model may be further configured to estimate, based at least in part on the start of combustion, a peak cylinder pressure associated with the combustion of the fuel and the air supplied to the cylinder.

Misfire and torque fluctuation due to rapid combustion deterioration of an internal combustion engine can be reduced. An ECU of an engine which burns fuel in a cylinder includes a determination unit which determines a target air-fuel ratio of the engine on the basis of a variation in crank angle in a relatively small number of combustion cycles, or a difference in indicated average effective pressure from a previous combustion cycle, and an air-fuel ratio control unit which controls the air-fuel ratio of the engine to be the target air-fuel ratio determined by the determination unit. The determination unit shifts the target air-fuel ratio to a rich side when the variation exceeds a first setting value or when the difference exceeds a second setting value.

Provided is a control device and a control method of a high-efficiency internal combustion engine capable of stabilizing combustion and suppressing NO.sub.x emissions without unnecessarily increasing a mounting load on an ECU. Therefore, the control device of the internal combustion engine for controlling the internal combustion engine includes an ignition plug that ignites an air-fuel mixture of fuel and air in the combustion chamber, a combustion pressure estimation sensor that detects a combustion pressure in the combustion chamber, and a crank angle sensor that detects a crank angle of a crankshaft. An MBT region is set based on an ignition delay period from an ignition timing of the ignition plug calculated from a detection value of the combustion pressure estimation sensor and a detection value of the crank angle sensor to a combustion start timing in the combustion chamber, and a combustion period from the combustion start timing to a set amount combustion end timing when a set amount of combustion ends. An ignition timing of the ignition plug is controlled so as to fall within the set MBT region.

A method of controlling a dual fuel engine system includes adjusting a phasing control parameter such as air-fuel ratio (AFR), based on a phasing signal to limit an error in a phasing of combustion of gaseous fuel. The cylinder is switched to a dual fuel liquid pilot-ignited mode by commanding direct injection of an early pilot shot of liquid fuel, based on the adjustment to the phasing control parameter, and production of a spark to ignite gaseous fuel in the cylinder. Switching the cylinder to the dual fuel liquid pilot-ignited mode is completed by commanding direct injection of an early pilot shot and a second pilot shot of liquid fuel to ignite gaseous fuel in response to combustion of the early and second pilot shots in the cylinder.