Abstract: An exhaust gas after-treatment system for an internal combustion engine includes a selective catalyst reduction on filter (SCRF) exhaust gas after-treatment device in communication with exhaust gases from the internal combustion engine and having treated exhaust gas output. An oxides of nitrogen (NOx) sensor is coupled to treated exhaust gases and has a NOx sensor output signal that is NOx and ammonia (NH3) cross-sensitive. A closed loop observer (CLO) is operatively coupled to receive the NOx sensor output signal and provides a NOx concentration signal to an electronic control unit operatively associated with the exhaust gas after-treatment system and the internal combustion engine. CLO output at least includes an exhaust gas NOx concentration estimate and the ECU is arranged to be operable upon the NOx concentration estimate to control exhaust gas after-treatment system and internal combustion engine to effect an overall reduction in actual NOx concentration with the exhaust gases.

Abstract: A coolant pressure regulator system includes a coolant circuit, and a pressurized fluid circuit selectively fluidically connected to the coolant circuit. The pressurized fluid circuit includes a pump operably to selectively raising a pressure of coolant in the coolant circuit.

Abstract: A method to control an internal combustion engine including exhaust gas recirculation (EGR) system and an air charging system includes the following steps: (a) determining, via an engine controller, a first EGR mass flow rate using an orifice model; (b) determining, via the engine controller, a second EGR mass flow rate using a cylinder volumetric efficiency model; (c) determining, via the engine controller, a hybrid EGR mass flow rate based on the first EGR flow rate and the second EGR flow rate; and (d) controlling the air charging system based on the hybrid EGR flow rate.

Abstract: Examples of techniques for controlling the flow of a coolant fluid through a cooling system of an internal combustion engine are disclosed. In one example implementation, a method includes calculating, by a processing device, a minimum zone flow rate of the coolant fluid for a zone of a cooling system of the internal combustion engine. The method further includes converting, by the processing device, the minimum zone flow rate into a desired actuator position for a flow control valve to enable the flow control valve to provide the minimum zone flow rate of the coolant fluid to the zone of the cooling system. The method further includes enabling, by the processing device, the flow control valve to change from a current actuator position to the desired actuator position.

Abstract: Examples of techniques for controlling temperature of a coolant fluid at an inlet of an internal combustion engine are disclosed. In one example implementation, a method includes receiving, by a processing device, total fuel burned data indicating a total amount of fuel burned by the internal combustion engine. The method further includes receiving, by a processing device, engine speed data indicating an engine speed of the internal combustion engine. The method further includes calculating, by the processing device, a radiator flow rate to achieve a temperature set-point at an inlet of the engine based at least in part on the total fuel burned data and the engine speed data. The method further includes adjusting, by the processing device, a radiator flow based at least in part on the radiator flow rate.