Abstract: An exhaust emissions prediction system includes a catalytic device configured to receive a flow of exhaust and a downstream NOx sensor located downstream of the catalytic device. The downstream NOx sensor is sensitive to NOx and ammonia, and is configured to generate a measured value. The system also includes a controller connected to the downstream NOx sensor. The controller is configured to determine a predicted value for the downstream NOx sensor, determine a mass flow rate of the flow of exhaust into the catalytic device, adjust the mass flow rate based on the predicted value and the measured value, and determine at least one emissions characteristic downstream of the catalytic device using the adjusted mass flow rate.

Abstract: An exhaust emissions prediction system includes a catalytic device configured to receive a flow of exhaust and a downstream NOx sensor located downstream of the catalytic device. The downstream NOx sensor is sensitive to NOx and ammonia, and is configured to generate a measured value. The system also includes a controller connected to the downstream NOx sensor. The controller is configured to determine a predicted value for the downstream NOx sensor, determine a mass flow rate of the flow of exhaust into the catalytic device, adjust the mass flow rate based on the predicted value and the measured value, and determine at least one emissions characteristic downstream of the catalytic device using the adjusted mass flow rate.

Abstract: An exhaust treatment system includes a catalytic device configured to receive an exhaust flow and an injector upstream of the catalytic device in an exhaust flow direction that injects a reductant into the exhaust flow. A controller is configured to determine a change in an amount of NOx and a change in an amount of the reductant downstream of the catalytic device due to a change in an amount of the reductant injected by the injector. The controller is configured to determine a slip factor corresponding to a relative weight of a NOx slip rate exiting the catalytic device compared to a reductant slip rate exiting the catalytic device, and determine a dosing command for providing to the injector based at least in part on the slip factor, and the change in the amount of NOx and the change in the amount of the reductant downstream of the catalytic device.

Abstract: An exhaust treatment system for a power system is disclosed. The exhaust treatment system includes an exhaust conduit directing exhaust gas produced by the power system towards at least one exhaust treatment device. The exhaust treatment system may also include a substrate positioned within an enclosure of the at least one exhaust treatment device. The exhaust conduit may be configured to preheat the substrate with the exhaust gas prior to directing the exhaust gas into the enclosure.

Abstract: An exhaust treatment system includes an oxidation device having a plurality of channels through which a flow of exhaust flows. A first portion of the channels of the oxidation device are coated with catalytic material for converting NO to NO2 and a second portion of the channels are uncoated with the catalytic material. The exhaust treatment system also includes a selective catalytic reduction device disposed downstream from the oxidation device. The selective catalytic reduction device is configured to receive the flow of exhaust passing through the oxidation device.

Abstract: An exhaust gas treatment system of an internal combustion engine includes a selective catalytic reduction catalyst fluidly connected to the internal combustion engine, an oxidation catalyst fluidly connected upstream of the selective catalytic reduction catalyst, and a particulate filter fluidly connected upstream of the selective catalytic reduction catalyst. The exhaust gas treatment system further includes a recirculation line configured to direct a portion of an exhaust flow of the internal combustion engine toward an inlet of the engine.