Abstract: An exhaust control system comprises an absorption rate estimation module, a desorption rate estimation module, a rate of change module, a release rate estimation module, and a fuel control module. The absorption rate estimation module estimates a hydrocarbon energy absorption rate of a component of an exhaust system. The desorption rate estimation module estimates a hydrocarbon energy desorption rate of the component. The rate of change module that determines a stored energy rate of change based on a difference between the hydrocarbon absorption and desorption rates. The release rate estimation module estimates a hydrocarbon energy release rate for the component based on the stored energy rate of change. The fuel control module controls a rate of fuel injection into the exhaust system upstream of an oxidation catalyst based on the hydrocarbon energy release rate.

Abstract: An exhaust control system comprises a total loss determination module and a fuel control module. The total loss determination module determines a total energy loss rate of exhaust upstream of a location in an exhaust system based on a convective energy loss rate upstream of the location, a conductive energy loss rate upstream of the location, and an oxidation energy gain rate upstream of the location. The fuel control module receives a target temperature for the exhaust at the location and determines a target input energy rate based on the target temperature, a temperature of exhaust input to the exhaust system, and the total energy loss rate. The fuel control module controls a rate of fuel injection into the exhaust system upstream of an oxidation catalyst based on the target input energy rate.

Abstract: An exhaust control system comprises a nominal specific heat module, a correction module, a specific heat determination module, and a convective loss estimation module. The nominal specific heat module determines a nominal specific heat of exhaust input to a component of an exhaust system based on a temperature of the exhaust input to the component and based on a predetermined oxygen content. The correction module determines a specific heat correction based on an oxygen content measured by a sensor. The specific heat determination module determines a specific heat of the exhaust based on the nominal specific heat and the specific heat correction. The convection loss estimation module estimates a convective energy loss rate associated with the component based on the specific heat.

Abstract: An engine control system includes an injection determination module, a correction factor determination module, and a regeneration control module. The injection determination module determines a desired amount of hydrocarbons (HC) to inject into exhaust gas produced by an engine based a flow rate of the exhaust gas. The correction factor determination module determines a correction factor for the desired amount of HC based on engine speed and engine load. The regeneration control module controls injection of an adjusted amount of HC into the exhaust gas during regeneration of a particulate matter filter, wherein the adjusted amount of HC is based on the desired amount of HC and the correction factor.

Abstract: A method for operating an internal combustion engine (100) and exhaust system therefor includes the step of initiating a regeneration event in a diesel particulate filter (DPF 109) (401). A first oxygen concentration (213) of a gas upstream of the DPF 109, and a second oxygen concentration (215) of the gas downstream of the DPF 109 are sensed (403) to infer a rate of combustion of material in the DPF (405) based on the difference between the first (213) and the second (215) oxygen concentrations. The rate of combustion is compared to a threshold value (409) and the regeneration event in the DPF 109 is terminated (411) if the rate of combustion is above the threshold.

Abstract: De-sulfurizing a NOx adsorber catalyst (48) without significantly increasing the temperature of exhaust gases leaving the engine exhaust manifold (42) by using a diesel oxidation catalyst (46) between the exhaust manifold and the NOx adsorber catalyst to elevate exhaust gas temperature entering the NOx adsorber catalyst to suitable de-sulfurizing temperature through control of certain aspects of engine operation (24, 28, 52).