Operating a direct-injection compression-ignition engine includes injecting early pilot shots of fuel, and controlling a cylinder temperature timing to combust the early pilot shots according to a combustion phasing that is based on the cylinder temperature timing. A main charge of the fuel is combusted based on the combustion of the early pilot shots. A combustion control unit is structured to command actuation of a fuel injector and a cylinder temperature controller to phase combustion of early pilot shots of the fuel, prior to a TDC position of a piston in an engine cycle. The cylinder temperature controller is a variable valve actuator or other apparatus controlling cylinder temperature in a manner decoupled from piston position.

A method for updating a crank position tooth number in a crank position sensor signal obtained from a crankshaft position sensor of an engine of a vehicle includes: calculating, in platform software of an engine control unit (ECU), a pulse width of a crank position sensor signal, determining, in the platform software of the ECU, a forward rotation and a reverse rotation of an engine, and updating, in the platform software of the ECU, the crank position tooth number.

The present invention discloses a cold start operation device and control method for a diesel engine in a plateau region under a low ambient temperature, allowing a starter to drive a piston to compress the low-temperature air, by using the heated air as the fresh inlet air to introduce it into the cylinder, so that the in-cylinder temperature at the compressing TDC is increased to obtain the ignition temperature, and finally achieving the cold start of diesel engines in plateau regions. The present invention avoids complicated preheating devices, and has simple structure and reliable performance, can achieve effective cold start in different low ambient temperature environments.

According to one or more embodiments, an internal combustion engine may be operated by a method which includes one or more of passing a first fuel and a second fuel into an engine cylinder to form a fuel mixture, and combusting the fuel mixture with a spark plug to translate a piston housed in the engine cylinder and rotate a crank shaft coupled to the piston. The first fuel may comprise a greater octane rating than the second fuel. A target CA50 may correspond to a minimum in specific fuel consumption of the fuel mixture. The spark plug may initiate combustion at a time such that the internal combustion engine operates with an operational CA50 that is within 20 degrees of the target CA50.

Systems and methods for estimating an engine event location are disclosed herein. In one embodiment, a control system is configured to receive feedback from at least one vibration sensor coupled to a reciprocating engine, estimate an engine parameter based at least on the feedback and an Empirical Transform Function (ETF), estimate a location of an engine event based on the engine parameter, and adjust operation of the reciprocating engine based at least on the location of the engine event.

A method for monitoring an engine cylinder in an internal combustion engine includes, for each engine cycle, detection of the ionisation current generated in the cylinder in a predetermined time interval of a combustion cycle, generation of a signal representing the ionisation current and comparing a maximum value of the signal with a threshold value. Successively, the value of one or more parameters associated with the signal can be changed with respect to an equal number of corresponding reference values when the maximum value of the signal exceeds the threshold value, to reduce the maximum value of the signal in the time interval of a successive combustion cycle. The presence of water in the cylinder can be determined when the maximum value of the signal exceeds the threshold value for a predetermined first number of combustion cycles occurring within a predetermined period of time.

A Wiebe function parameter identification method, the method includes: acquiring, by a computer, operation data when an internal-combustion engine is in operation; and identifying values of a plurality of parameters included in a combination of at least two Wiebe functions including a first Wiebe function and a second Wiebe function based on the operation data and a first difference between values of a same parameter of the first Wiebe function and the second Wiebe function.

An engine control system includes: a delay estimating unit configured to estimate a auto-ignition delay based on first parameters including a composition of fuel gas; a auto-ignition predicting unit configured to predict a auto-ignition timing based on the auto-ignition delay; a completion predicting unit configured to predict a combustion completion timing of the fuel gas; and an operation control unit configured to control an engine based on a result of comparison between the auto-ignition timing and the combustion completion timing.

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 control device for a compression self-ignition engine includes a fuel injection system and an injection controller. While the engine is operated by CI combustion under a given first condition, a first injection is carried out in which fuel is injected at a first timing in a compression stroke and at which the fuel goes toward a part radially outward of a cavity formed in a crown surface of a piston, and a second injection is suspended. While the engine is operated by the CI combustion under a second condition in which a temperature inside a combustion chamber at a close timing of an intake valve becomes lower than the first condition, at least the second injection is carried out in which the fuel is injected at a second timing later than the first timing in the compression stroke and at which the fuel goes toward the cavity.