Abstract: A method for monitoring an exhaust after-treatment system that doses an exhaust treatment fluid held from a tank into an exhaust stream. The method includes determining a first temperature of the exhaust treatment fluid in the tank using a temperature sensor. If the first temperature of the exhaust treatment fluid is less than a predetermined temperature, a heater is activated to increase the first temperature of the exhaust treatment fluid. The increasing first temperature is then monitored relative to the predetermined temperature. Then, a second temperature when a phase change of the exhaust treatment fluid occurs is detected. The detected second temperature is then compared to the predetermined temperature to determine whether the exhaust treatment fluid is of sufficient quality, or to determine whether the temperature sensor is rational.

Abstract: A method for monitoring an exhaust after-treatment system that doses an exhaust treatment fluid held from a tank into an exhaust stream. The method includes determining a first temperature of the exhaust treatment fluid in the tank using a temperature sensor. If the first temperature of the exhaust treatment fluid is less than a predetermined temperature, a heater is activated to increase the first temperature of the exhaust treatment fluid. The increasing first temperature is then monitored relative to the predetermined temperature. Then, a second temperature when a phase change of the exhaust treatment fluid occurs is detected. The detected second temperature is then compared to the predetermined temperature to determine whether the exhaust treatment fluid is of sufficient quality, or to determine whether the temperature sensor is rational.

Abstract: A reagent injector control system includes a pulse width modulation (PWM) control module and an injector driver module. The PWM control module monitors current through a reagent injector during an injection control cycle, generates a PWM signal based on an amount of reagent to be injected during the injection control cycle, and at least one of selectively increases and selectively decreases a duty cycle of a PWM signal during the injection control cycle based on the current. The injector driver module selectively enables and disables the current based on the PWM signal. The reagent injector opens and injects a reagent into an exhaust system based on the current. The exhaust system receives exhaust output from an engine. The reagent reacts with nitrogen oxides (NOx).

Abstract: An exhaust gas treatment system for reducing emissions from an engine includes an exhaust conduit adapted to supply an exhaust stream from the engine to an exhaust treatment device. The conduit includes an aperture. An injector injects a reagent through the aperture and into the exhaust stream. A flow modifier is positioned within the exhaust conduit upstream of the injector. The flow modifier includes a diverter for increasing the velocity of the exhaust gas at a predetermined location within the conduit relative to the injected reagent.

Abstract: A control system for reducing nitrogen oxides in an engine exhaust of an engine includes an emissions catalyst having an inlet adapted to receive an exhaust from the engine. A reductant tank stores a reductant. An injector is in fluid communication with the reductant tank and is operable to inject the reductant into the exhaust upstream of the catalyst. A reductant pump pumps the reductant from the reductant tank to the injector. A controller determines a target pressure of the reductant based on an engine operating condition and operates the reductant pump based on the target pressure.

Abstract: A reagent injector control system includes a pulse width modulation (PWM) control module and an injector driver module. The PWM control module monitors current through a reagent injector during an injection control cycle, generates a PWM signal based on an amount of reagent to be injected during the injection control cycle, and at least one of selectively increases and selectively decreases a duty cycle of a PWM signal during the injection control cycle based on the current. The injector driver module selectively enables and disables the current based on the PWM signal. The reagent injector opens and injects a reagent into an exhaust system based on the current. The exhaust system receives exhaust output from an engine. The reagent reacts with nitrogen oxides (NOx).

Abstract: An exhaust gas treatment system for reducing emissions from an engine includes an exhaust conduit adapted to supply an exhaust stream from an engine to an exhaust treatment device. An injector injects a reagent through an aperture in the conduit into the exhaust stream. A vortex breaker includes a mount having a cylindrical sleeve extending through the aperture as well as a flared tube fixed to and positioned within the cylindrical sleeve. A window extends through an upstream portion of the cylindrical sleeve exposing the flared tube to the exhaust stream. The sleeve includes a downstream aperture in fluid communication with the window.

Abstract: An exhaust gas treatment system for reducing emissions from an engine includes an exhaust conduit adapted to supply an exhaust stream from the engine to an exhaust treatment device. The conduit includes an aperture. An injector injects a reagent through the aperture and into the exhaust stream. A flow modifier is positioned within the exhaust conduit upstream of the injector. The flow modifier includes a diverter for increasing the velocity of the exhaust gas at a predetermined location within the conduit relative to the injected reagent.

Abstract: A control system for reducing nitrogen oxides in an engine exhaust of an engine includes an emissions catalyst having an inlet adapted to receive an exhaust from the engine. A reductant tank stores a reductant. An injector is in fluid communication with the reductant tank and is operable to inject the reductant into the exhaust upstream of the catalyst. A reductant pump pumps the reductant from the reductant tank to the injector. A controller determines a target pressure of the reductant based on an engine operating condition and operates the reductant pump based on the target pressure.

Abstract: A reductant heating system may include a reductant tank, a reductant tank flange and a hollow tube residing within the reductant tank and passing through the reductant tank flange in two locations to carry coolant into and out of the reductant tank. The reductant heating system may further include a resistive wire wrapped around the hollow tube within the reductant tank and an electrical supply cord located outside of the reductant tank that supplies electrical power to the resistive wire. A temperature detector may be disposed within the reductant tank to detect a temperature within the reductant tank and govern electricity flow to the resistive wire. That is, the temperature detector may be wired in-line in the resistive wire and may be a thermal switch attached to the hollow tube. In another embodiment, the temperature detector may be a thermocouple that senses a temperature within the reductant tank.

Abstract: An exhaust gas treatment system for reducing emissions from an engine includes an exhaust conduit adapted to supply an exhaust stream from an engine to an exhaust treatment device. An injector injects a reagent through an aperture in the conduit into the exhaust stream. A vortex breaker includes a mount having a cylindrical sleeve extending through the aperture as well as a flared tube fixed to and positioned within the cylindrical sleeve. A window extends through an upstream portion of the cylindrical sleeve exposing the flared tube to the exhaust stream. The sleeve includes a downstream aperture in fluid communication with the window.