An engine control method includes a step of setting combustion mode in which a first combustion mode in which a mixed gas is combusted by propagating flame or a second combustion mode in which the mixed gas is combusted by self-ignition is selected, a step of setting air-fuel ratio mode in which a lean first air-fuel ratio mode or a second air-fuel ratio mode equal to or richer than a theoretical air-fuel ratio is selected, a step of setting torque reduction in which a torque reduction amount by which a torque generated by an engine is reduced based on a steer angle of a steering wheel, and a suppressing step in which reducing the torque generated by the engine based on the torque reduction amount set in the step of setting torque reduction is suppressed.

Some embodiments described herein relate to a method of operating a compression ignition engine. The method of operating the compression ignition engine includes opening an intake valve to draw a volume of air into a combustion chamber, closing an intake valve, and moving a piston from a bottom-dead-center (BDC) position to a top-dead-center (TDC) position in the combustion chamber at a compression ratio of at least about 15:1. The method further includes injecting a volume of fuel into the combustion chamber at an engine crank angle between about 330 degrees and about 365 degrees during a first time period. The fuel has a cetane number less than about 40. The method further includes combusting substantially all of the volume of fuel. In some embodiments, a delay between injecting the volume of fuel into the combustion chamber and initiation of combustion is less than about 2 ms.

A method, a combustion engine controller, and a combustion engine incorporating the controller to implement the method are provided. The method includes determining a first dedicated exhaust gas recirculation (D-EGR) cylinder parameter value of a first D-EGR cylinder parameter associated with a first D-EGR cylinder of the combustion engine; and regenerating the first D-EGR cylinder responsive to the first D-EGR cylinder parameter value satisfying a threshold indicative of a carbon build-up level.

A control device for a compression ignition engine includes a controller configured to operate an engine body by compression ignition combustion when the engine body operates in a predetermined compression ignition range. When the engine body operates in a predetermined high load range of the compression ignition range, the controller maximizes a filling amount of the cylinder using a gas state adjustment system, and lowers an EGR ratio so that the air-fuel mixture in the cylinder is lean with an excess air ratio λ higher than 1 in a lower speed range, and maximizes the filling amount of the cylinder, and increases the EGR ratio so that the air-fuel mixture in the cylinder has the excess air ratio λ of 1 or lower in a higher speed range than the lower speed range.

Some embodiments described herein relate to a method of operating a compression ignition engine. The method of operating the compression ignition engine includes opening an intake valve to draw a volume of air into a combustion chamber, closing an intake valve, and moving a piston from a bottom-dead-center (BDC) position to a top-dead-center (TDC) position in the combustion chamber at a compression ratio of at least about 15:1. The method further includes injecting a volume of fuel into the combustion chamber at an engine crank angle between about 330 degrees and about 365 degrees during a first time period. The fuel has a cetane number less than about 40. The method further includes combusting substantially all of the volume of fuel. In some embodiments, a delay between injecting the volume of fuel into the combustion chamber and initiation of combustion is less than about 2 ms.

A control unit performs a vehicle attitude control to reduce a torque generated by an engine when an increase in a steering angle exceeds a standard increase, and a spark ignition controlled compression ignition combustion in a predetermined operating range. In the spark ignition controlled compression ignition combustion, switching of an air-fuel ratio mode is performed between a first air-fuel ratio mode (λ>1) is formed and a second air-fuel ratio mode (in which a mixed gas of λ≤1) is formed. If the switching of the air-fuel ratio mode is requested without the vehicle attitude control, the control unit allows performing the requested switching of the air-fuel ratio mode. In contrast, if the mode switching is requested in a state where the vehicle attitude control is requested, the control unit disallows switching of the air-fuel ratio mode even when the switching of the air-fuel ratio mode is requested.

Some embodiments described herein relate to a method of operating a compression ignition engine. The method of operating the compression ignition engine includes opening an intake valve to draw a volume of air into a combustion chamber, closing an intake valve, and moving a piston from a bottom-dead-center (BDC) position to a top-dead-center (TDC) position in the combustion chamber at a compression ratio of at least about 15:1. The method further includes injecting a volume of fuel into the combustion chamber at an engine crank angle between about 330 degrees and about 365 degrees during a first time period. The fuel has a cetane number less than about 40. The method further includes combusting substantially all of the volume of fuel. In some embodiments, a delay between injecting the volume of fuel into the combustion chamber and initiation of combustion is less than about 2 ms.

A control device includes an integrated circuit configured to receive a control signal from a central computing device via a communication path, and control operation of an actuator of a rotation output device based on the received control signal. The central computing device has a memory that stores a model representing an operation pattern of the actuator. The control signal is a signal including a desired operation pattern of the actuator that is based on the model and a desired operation start time of the desired operation pattern. The integrated circuit controls the operation of the actuator using the desired operation pattern at the desired operation start time and receives a next control signal representing a next operation pattern and a next operation start time of the next operation pattern after the desired operation pattern is executed or during execution of the desired operation pattern.

The present disclosure envisages an engine control system (100) that enables multi-mode drivability in off-road vehicles. The system (100) comprises a mode selection device (101) and an electronic control unit (ECU) (104). The mode selection device (101) is configured to receive an input from an operator for selection of at least one mode of engine operation, and to generate a mode selection signal corresponding to the input. The electronic control unit (ECU) (104) is communicatively coupled with the mode selection device (101) to receive the mode selection signal and generate at least one control signal. The electronic control unit (ECU) (104) is further configured to control a fuel injection system (106) of the vehicle based on the selected mode according to the load requirement, thereby facilitating multi-mode drivability. The system (100) allows a vehicle to operate in different operating modes as per terrain conditions.

Methods and systems are provided for reducing exhaust residuals during light load conditions in a split exhaust engine via a check valve. In one example, a scavenge exhaust manifold may be maintained above a threshold pressure by introducing fresh air into the scavenge manifold during a valve overlap period, the scavenge manifold coupled to a cylinder of an engine and coupled to an intake passage of the engine.