Apparatus, method and system for diagnosing reductant deposits in an exhaust aftertreatment system

摘要

An exhaust gas treatment system for an internal combustion engine may have a reductant delivery system that delivers reductant to an exhaust stream in an exhaust aftertreatment system. A temperature sensor may be positioned in or near the flow of reductant and exhaust to measure the temperature of the reductant and exhaust. A change in temperature over time, such as an increase, decrease, or change in variation amplitude, may indicate the presence of a reductant deposit in the system. Detection of the deposit may initiate a regeneration cycle in which the operating characteristics of the system change to eliminate the reductant deposit to prevent it from hindering the performance of the exhaust aftertreatment system.

主权项

1. An apparatus for diagnosing existence of reductant deposits in an exhaust aftertreatment system having a reductant delivery system that, delivers reductant to exhaust gas produced by an internal combustion engine to provide a mixture of exhaust gas and reductant, and a control module that operates the reductant delivery system, the apparatus comprising:
a sampling module configured to sample a first temperature of the mixture of exhaust gas and reductant at a first time and a second temperature of the mixture of exhaust gas and reductant at a second time; a calculation module configured to calculate a temperature differential between the first temperature and the second temperature; a comparison module configured to compare the temperature differential with a threshold temperature differential to determine whether a reductant deposit exists within the exhaust aftertreatment system, the threshold temperature differential comprising a predetermined value indicative of a presence of a reductant deposit in a decomposition chamber of the exhaust aftertreatment system; a reporting module configured to output a performance status indicative of whether the reductant deposit exists in the decomposition chamber of the exhaust aftertreatment system based on the comparison of the temperature differential with the threshold temperature differential; and a regeneration module configured to receive the performance status from the reporting module and initiate a regeneration cycle of the exhaust aftertreatment system to at least partially remove the reductant deposit from the decomposition chamber responsive to the performance status being indicative of the reductant deposit existing in the decomposition chamber.