A method and a system for control of a dosage device and/or an engine that produces an exhaust stream (203) treated by an exhaust treatment system (250) that injects at least one additive into the exhaust stream (203) with a dosage device (271) to evaporate in an evaporation chamber (280). The method includes determining a time dependent condition of a position at an internal wall (281) of the evaporation chamber (280), the condition being determined based on the internal temperature related to the position, the internal temperature being determined based on a temperature model for the evaporation chamber (280) and an exhaust temperature for the exhaust stream (203) upstream of the evaporation chamber (208); determining a risk for at least one spatially resolved critical condition related to the position based on the time dependent condition, and controlling the dosage device (271) and/or the engine based on the determined risk.

A control system for a heating system of an exhaust system is provided. The control system includes at least one electric heater disposed within an exhaust fluid flow pathway, and a control device adapted to receive at least one input selected from the group consisting of mass flow rate of an exhaust fluid flow, mass velocity of an exhaust fluid flow, flow temperature upstream of the at least one electric heater, flow temperature downstream of the at least one electric heater, power input to the at least one electric heater, parameters derived from physical characteristics of the heating system, and combinations thereof. The control device is operable to modulate power to the at least one electric heater based on at least one input.

An exhaust gas analysis apparatus includes an exhaust gas flow channel, a pump, and a heat exchanger. The exhaust gas flow channel is designed to permit passage of exhaust gas of an internal combustion engine, and is provided with an analysis device. The pump is disposed downstream of the analysis device in the exhaust gas flow channel. The heat exchanger is designed to receive at least one of heat of the pump and heat of exhaust gas passing downstream of the pump, and to use the heat to heat exhaust gas passing upstream of the pump in the exhaust gas flow channel.

There is provided an exhaust treatment device for a diesel engine capable of accurately estimating an amount of ash deposition. In the exhaust treatment device, an ash deposition estimation device estimates an amount of ash deposition on a DPF after ending of regenerating treatment for the DPF, based on data regarding differential pressure and exhaust flow rate stored in a memory device over a period immediately before the end of regeneration, the period ranging from the end point of regenerating treatment for the DPF to a point in time going back a predetermined duration. An electronic control device preferably makes an alarm device issue an alarm, upon arrival of an estimated value of ash deposition at a predetermined alarm request value.

The present invention is an exhaust gas flow rate measuring unit that eliminates the disturbance of the flow velocity distribution of exhaust gas flowing through an attachment pipe to accurately measure an exhaust gas flow rate, and is mounted in a vehicle to measure the flow rate of exhaust gas emitted from an exhaust pipe of the vehicle. In addition, the exhaust gas flow rate measuring unit includes the attachment pipe that is connected to the exhaust pipe and forms a flow path through which the exhaust gas flows, a flowmeter that is provided in the flow path and measures the flow rate of the exhaust gas flowing through the flow path, and a straightening mechanism that is provided on the upstream side of the flowmeter in the flow path.

An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway that receives exhaust gas from the engine, a temperature sensor configured to generate a temperature signal associated with a temperature of the exhaust gas at a position along the exhaust gas pathway, and a reductant source. The system also includes first and second injectors in fluid communication with the reductant source. The first and second injectors are configured to inject reductant into the exhaust gas pathway at first and second rates. The system also includes a first treatment element positioned downstream of the first injector and within the exhaust gas pathway, and a controller in communication with the temperature sensor. The controller is configured to receive the temperature signal from the temperature sensor and adjust at least one of the first rate or the second rate based at least in part on the temperature signal.

A vehicle exhaust system includes a first exhaust after-treatment module that receives engine exhaust gases and a second exhaust after-treatment module that is downstream of the first exhaust after-treatment module. A valve is moveable between an open position that blocks flow to the first exhaust after-treatment module such that all exhaust gas flow bypasses the first exhaust after-treatment module and is directed into the second exhaust after-treatment module, a closed position that directs flow into the first exhaust after-treatment module before the flow enters the second exhaust after-treatment module, and a partially open position where one portion of flow is directed into the first exhaust after-treatment module and a remaining portion of flow is directed into the second exhaust after-treatment module. A controller controls movement of the valve between the open, closed, and partially open positions based on at least one of engine flow rate and NOx output.

A method of predicting temperature of at least one location in a fluid flow system that has a heating system for heating fluid. The method includes obtaining a mass flow rate of fluid flow of the fluid flow system, obtaining at least one of a fluid outlet temperature and a fluid inlet temperature of a heater of the heating system, obtaining power provided to the heater, and calculating temperature at the at least one location based on a model of the fluid flow system and the obtained mass flow rate, fluid outlet temperature, and fluid inlet temperature.

A method for controlling exhaust flow in an EATS of a vehicle. A NO.sub.x sensor output parameter is monitored. It is determined that the NO.sub.x sensor output parameter is below a limit. When the NO.sub.x sensor output parameter is below the limit, it is determined that a first part of the exhaust flow should bypass at least a first area of the SCR unit and that a second part of the exhaust flow should be inputted to at least the first area of the SCR unit. It is initiated that the first part is bypassed and that the second part is inputted to at least the first area of the SCR unit. An amount of reductant that should be added to the second part of the exhaust flow is determined. Addition of the amount of reductant is initiated.

A susceptor for use in a heated fluid flow system is provided. In one form, a susceptor is arranged within a conduit and adapted to absorb radiant energy from at least one heating element and inhibit the radiant energy from being absorbed by the at least one wall of the conduit and/or other components. In another form, the susceptor absorbs and inhibits the radiant energy from being absorbed by the outer wall of the conduit.