Abstract: System, apparatus, and methods are disclosed for reductant dosing in an exhaust aftertreatment system. A dynamic flow rate and injection duration of a reductant injected from a reductant dosing system to the exhaust aftertreatment system is controlled in response to a dosing command when the exhaust system is operating in a low temperature operating condition.

Abstract: System, apparatus, and methods are disclosed for reductant dosing in an exhaust aftertreatment system. A dynamic flow rate and injection duration of a reductant injected from a reductant dosing system to the exhaust aftertreatment system is controlled in response to a dosing command when the exhaust system is operating in a low temperature operating condition.

Abstract: A preferred embodiment EGR valve permits exhaust gas to be induced into the intake line downstream of the compressor, while minimizing the need to reduce the size of the turbocharger. The preferred embodiment EGR valve exploits variations around the mean pressure in the EGR passage created by the engine cycle by selectively opening when the pressure in the EGR valve exceeds the pressure in the intake line. Thus, exhaust gas is recirculated even when the engine is running near torque peak. The preferred embodiment EGR valve also exploits the higher mean pressure in the exhaust line relative to the intake line at higher engine speeds by remaining open, in order to minimize the energy consumed in opening and closing the EGR valve.

Abstract: An exhaust gas recirculation and control system is provided for an internal combustion engine, wherein a portion of engine exhaust gas flow is recirculated through an EGR duct to engine intake air. The recirculated exhaust gas is pumped through the EGR duct by an EGR compressor driven by a dedicated EGR drive that is independently controllable. Because the EGR drive is independently powered and controlled, the EGR flow rate capacity of the system is not dictated by, or limited, by factors such as engine exhaust flow rate. A controller modulates power delivery to the drive means in response to at least one operating condition parameter in order to achieve a desired EGR flow rate. In order to further optimize efficiency, the EGR compressor is preferably a discrete displacement pump which is controllably drivable in a pulse-capture mode, wherein each intake of the EGR compressor is timed synchronously with exhaust pulses in the exhaust manifold.

Abstract: An exhaust gas recirculation and control system is provided for an internal combustion engine, wherein a portion of engine exhaust gas flow is recirculated through an EGR duct to engine intake air. The recirculated exhaust gas is pumped through the EGR duct by an EGR compressor driven by a dedicated EGR drive that is independently controllable. Because the EGR drive is independently powered and controlled, the EGR flow rate capacity of the system is not dictated by, or limited, by factors such as engine exhaust flow rate. A controller modulates power delivery to the drive means in response to at least one operating condition parameter in order to achieve a desired EGR flow rate. In order to further optimize efficiency, the EGR compressor is preferably a discrete displacement pump which is controllably drivable in a pulse-capture mode, wherein each intake of the EGR compressor is timed synchronously with exhaust pulses in the exhaust manifold.

Abstract: A flow control valve having a controllable flow area which varies with the valve displacement. The flow control valve includes a poppet-type valve element mounted to reciprocate between a closed and open position in a valve cavity formed in a valve housing. The valve housing has an inlet and outlet passage to allow fluid to flow therethrough. A removable insert having a flow passage is positioned in the valve cavity adjacent the poppet-valve for controlling the flow rate of gaseous fluid from the inlet passage to the outlet passage while the poppet valve is in an open position. Movement of the poppet valve from a closed to an open position varies the effective cross-sectional flow area of the flow passage.

Abstract: An exhaust gas recirculation and control system is provided for an internal combustion engine, wherein a portion of engine exhaust gas flow is recirculated through an EGR duct to engine intake air. The recirculated exhaust gas is pumped through the EGR duct by an EGR compressor driven by a dedicated EGR drive that is independently controllable. Because the EGR drive is independently powered and controlled, the EGR flow rate capacity of the system is not dictated by, or limited, by factors such as engine exhaust flow rate. A controller modulates power delivery to the drive means in response to at least one operating condition parameter in order to achieve a desired EGR flow rate. In order to further optimize efficiency, the EGR compressor is preferably a discrete displacement pump which is controllably drivable in a pulse-capture mode, wherein each intake of the EGR compressor is timed synchronously with exhaust pulses in the exhaust manifold.

Abstract: A flow control valve having a controllable flow area which varies with the valve displacement. The flow control valve includes a poppet-type valve element mounted to reciprocate between a closed and open position in a valve cavity formed in a valve housing. The valve housing has an inlet and outlet passage to allow fluid to flow therethrough. A removable insert having a flow passage is positioned in the valve cavity adjacent the poppet-valve for controlling the flow rate of gaseous fluid from the inlet passage to the outlet passage while the poppet valve is in an open position. Movement of the poppet valve from a closed to an open position varies the effective cross-sectional flow area of the flow passage.