Abstract: A configuration for a uniflow-scavenged, opposed-piston engine reduces exhaust cross-talk caused by mass flow between cylinders resulting from one cylinder having an open exhaust port during scavenging and/or charging while an adjacent cylinder is undergoing blowdown. Some configurations include a wall or other barrier feature between cylinders that are adjacent to each other and fire one after the other. Additionally, or alternatively, some engine configurations include cylinders with intake and exhaust ports sized so that there is an overlap in crank angle of two or more cylinders having open exhaust ports of about 65 crank angle degrees or less.

Abstract: Exhaust temperature management strategies for an opposed-piston, two-stroke engine with EGR are based on control of a ratio of the mass of fresh air and external EGR delivered to a cylinder to the mass of the trapped charge (density of the delivered charge multiplied by the trapped volume at port closing).

Abstract: Exhaust temperature management strategies for an opposed-piston, two-stroke engine with EGR are based on control of a ratio of the mass of fresh air and external EGR delivered to a cylinder to the mass of the trapped charge (density of the delivered charge multiplied by the trapped volume at port closing).

Abstract: A power system and a method for energizing an electrically heated catalyst are provided. The system includes a battery outputting a first voltage, and a generator outputting a second voltage greater than the first voltage in response to a first signal. The system further includes a controller that generates a second signal to set a first switching device to a first operational state to apply the second voltage to the electrically heated catalyst to increase a temperature of the catalyst, if a first temperature level of the catalyst is less than a first threshold temperature level. The controller generates a third signal to induce the generator to output a third voltage, and generates a fourth signal to set a second switching device to a second operational state to apply the first voltage to the catalyst, if the first temperature level is greater than the first threshold temperature level.

Abstract: An exhaust gas treatment system is provided, having an internal combustion engine, an exhaust gas conduit, an electrically heated catalyst (“EHC”) device, an oxidization catalyst (“OC”) device, an OC temperature sensor, a hydrocarbon (“HC”) adsorber, and a control module. The hydrocarbon supply is selectively activated for delivery of a hydrocarbon and formation of an exhaust gas and hydrocarbon mixture therein. The EHC device is selectively activated to produce heat and induce oxidization. The OC device is in fluid communication with the exhaust gas conduit and located downstream of the EHC device. The OC temperature sensor is in fluid communication with the exhaust gas conduit and located downstream of the OC device. The HC adsorber is located downstream of the EHC device. The control module is in communication with the hydrocarbon supply, the EHC device, the OC device, the OC temperature sensor, and the HC adsorber.

Abstract: Exhaust temperature management strategies for an opposed-piston, two-stroke engine with EGR are based on control of a ratio of the mass of fresh air and external EGR delivered to a cylinder to the mass of the trapped charge (density of the delivered charge multiplied by the trapped volume at port closing).

Abstract: A method of controlling airflow of an engine system is provided. The method includes determining a supercharger operating mode and a turbocharger operating mode based on engine load; selectively generating a control signal to a turbocharger based on the turbocharger operating mode; and selectively generating a control signal to a supercharger bypass valve based on the supercharger operating mode.

Abstract: An exhaust gas treatment system is provided having an internal combustion engine, an exhaust gas conduit, a passive selective catalyst reduction (SCR) device, a heated SCR device, and a control module. The exhaust gas conduit is in fluid communication with and is configured to receive an exhaust gas from the internal combustion engine. The passive SCR device is in fluid communication with the exhaust gas conduit and is configured to receive the exhaust gas. The passive SCR includes a passive SCR temperature profile. The heated SCR device is in fluid communication with the exhaust gas conduit and is configured to receive the exhaust gas. The heated SCR device is located upstream of the passive SCR. The heated SCR is selectively activated to produce heat. The control module is in communication with the heated SCR and the engine and includes a control logic for determining the passive SCR temperature profile.

Abstract: A method of controlling airflow of an engine system is provided. The method includes determining a supercharger operating mode and a turbocharger operating mode based on engine load; selectively generating a control signal to a turbocharger based on the turbocharger operating mode; and selectively generating a control signal to a supercharger bypass valve based on the supercharger operating mode.

Abstract: In one exemplary embodiment of the invention, an internal combustion engine includes a turbocharger configured to receive an air flow and a first exhaust flow from the internal combustion engine and a supercharger downstream of the turbocharger configured to receive a compressed air charge from the turbocharger. The engine further includes an exhaust gas recirculation circuit receiving a second exhaust flow from the internal combustion engine and supplying the second exhaust flow to the compressed air charge upstream of the supercharger, wherein the second exhaust flow and compressed air charge comprise an exhaust-air mixed flow received by the internal combustion engine.

Abstract: An exhaust gas treatment system is provided, having an internal combustion engine, an exhaust gas conduit, an electrically heated catalyst (“EHC”) device, an oxidization catalyst (“OC”) device, an OC temperature sensor, a hydrocarbon (“HC”) adsorber, and a control module. The hydrocarbon supply is selectively activated for delivery of a hydrocarbon and formation of an exhaust gas and hydrocarbon mixture therein. The EHC device is selectively activated to produce heat and induce oxidization. The OC device is in fluid communication with the exhaust gas conduit and located downstream of the EHC device. The OC temperature sensor is in fluid communication with the exhaust gas conduit and located downstream of the OC device. The HC adsorber is located downstream of the EHC device. The control module is in communication with the hydrocarbon supply, the EHC device, the OC device, the OC temperature sensor, and the HC adsorber.

Abstract: A power system and a method for energizing an electrically heated catalyst are provided. The system includes a battery outputting a first voltage, and a generator outputting a second voltage greater than the first voltage in response to a first signal. The system further includes a controller that generates a second signal to set a first switching device to a first operational state to apply the second voltage to the electrically heated catalyst to increase a temperature of the catalyst, if a first temperature level of the catalyst is less than a first threshold temperature level. The controller generates a third signal to induce the generator to output a third voltage, and generates a fourth signal to set a second switching device to a second operational state to apply the first voltage to the catalyst, if the first temperature level is greater than the first threshold temperature level.

Abstract: An exhaust gas treatment system is provided having an internal combustion engine, an exhaust gas conduit, a passive selective catalyst reduction (SCR) device, a heated SCR device, and a control module. The exhaust gas conduit is in fluid communication with and is configured to receive an exhaust gas from the internal combustion engine. The passive SCR device is in fluid communication with the exhaust gas conduit and is configured to receive the exhaust gas. The passive SCR includes a passive SCR temperature profile. The heated SCR device is in fluid communication with the exhaust gas conduit and is configured to receive the exhaust gas. The heated SCR device is located upstream of the passive SCR. The heated SCR is selectively activated to produce heat. The control module is in communication with the heated SCR and the engine and includes a control logic for determining the passive SCR temperature profile.

Abstract: An engine control module includes a power module and a turbine temperature module. The power module controls engine power output based on a turbine temperature. The turbine temperature module determines the turbine temperature based on a turbine inlet temperature. The power module decreases the engine power output when the turbine temperature is greater than or equal to a predetermined threshold temperature.