Forced regeneration of a diesel particulate filter

A method of imposing a forced regeneration cycle on a diesel particulate filter that treats exhaust gas passing through an exhaust system of a diesel engine to force regeneration of the filter, the method comprising:

• providing engine fueling data representing engine fueling in the absence of forced regeneration of the filter;
• during engine running time, repeatedly processing data that represents parameters useful in determining a rate at which diesel particulate matter (DPM) is accumulating in the filter through a DPM accumulation model to yield values of DPM accumulation representing accumulation of DPM in the filter at various points of time during engine running time;
• processing the values of DPM accumulation and data that distinguishes DPM accumulation values calling for forced regeneration of the filter from those not calling for forced regeneration of the filter;
• when a result of the latter processing discloses that a DPM accumulation value calls for forced regeneration of the filter, initiating forced regeneration by retarding the timing of engine fueling to elevate the exhaust gas temperature to a temperature for forcing regeneration of the filter;
• as the forced regeneration cycle progresses, repeatedly processing baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle, engine speed data that represents engine speed, data representing light off temperature of catalytic material of the filter, and data representing actual temperature of the catalytic material, to yield adjusted timing values for timing of engine fueling and fueling modification values;
• processing the engine fueling data and the fueling modification values to yield adjusted fueling values;
• using the adjusted fueling values instead of the engine fueling data for fueling the engine during the forced regeneration cycle;
• and
• using the adjusted timing values for the timing of engine fueling during the forced regeneration cycle.

A method of imposing a forced regeneration cycle on a diesel particulate filter that treats exhaust gas passing through an exhaust system of a diesel engine to force regeneration of the filter, the method comprising:

• providing engine fueling data representing engine fueling in the absence of forced regeneration of the filter;
• during engine running time, repeatedly processing data that represents temperature of exhaust gas entering the filter, data that represents exhaust gas flow entering the filter, and data that utilizes both exhaust gas temperature and flow to distinguish a filter that has trapped an amount of diesel particulate matter (DPM) calling for forced regeneration from a filter that does not call for forced regeneration to yield result data that a) calls for forced regeneration of the filter when the data that represents temperature of exhaust gas entering the filter and the data that represents exhaust gas flow entering the filter disclose that the filter has trapped an amount of DPM calling for forced regeneration, and b) calls for no forced regeneration when the data that represents temperature of exhaust gas entering the filter and the data that represents exhaust gas flow entering the filter disclose that the filter does not call for regeneration;
• when the result data calls for forced regeneration of the filter, initiating forced regeneration by retarding the timing of engine fueling to elevate the exhaust gas temperature to a temperature for forcing regeneration of the filter;
• as the forced regeneration cycle progresses, repeatedly processing, baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle, engine speed data that represents engine speed, data representing light off temperature of catalytic material of the filter, and data representing actual temperature of the catalytic material, to yield adjusted timing values for timing of engine fueling and fueling modification values;
• processing the engine fueling data and the fueling modification values to yield adjusted fueling values;
• using the adjusted fueling values instead of the engine fueling data for fueling the engine during the forced regeneration cycle;
• and
• using the adjusted timing values for the timing of engine fueling during the forced regeneration cycle.

A method of imposing a forced regeneration cycle on a diesel particulate filter that treats exhaust gas passing through an exhaust system of a diesel engine to force regeneration of the filter, the method comprising:

• during engine running time, repeatedly processing data that represents a rate at which diesel particulate matter (DPM) from the engine is entering the exhaust system, data that represents a rate at which DPM is being oxidized in the exhaust system, and data that represents DPM trapping efficiency of the filter, to yield values representing net rate at which DPM is being trapped in the filter at various points of times during the engine running time;
• processing the values representing net rate at which DPM is being trapped in the filter and data representing effective geometric size of DPM trapping medium in the filter to yield values representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium;
• processing the values representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium and data distinguishing values of DPM trapped in the filter per unit of geometric size of the DPM trapping medium that call for forced regeneration of the filter from those that do not call for forced regeneration;
• and
• when a result of the latter processing discloses that a value of data representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium calls for regeneration of the filter, operating the engine in an elevated temperature mode of operation that elevates the exhaust gas temperature to a temperature for forcing regeneration of the filter, and
• when a subsequent result discloses that a value of data representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium does not call for regeneration of the filter, discontinuing operation of the engine in the elevated temperature mode of operation.

A method of imposing a forced regeneration cycle on a diesel particulate filter that treats exhaust gas passing through an exhaust system of a diesel engine to force regeneration of the filter, the method comprising:

• during engine running time, repeatedly processing data for a first set of engine operating parameters to yield values representing amounts of accumulation of diesel particulate matter (DPM) in the filter at various points of times during the engine running time;
• during engine running time, repeatedly processing data for a second set of engine operating parameters different from the first set of engine operating parameters to yield values representing amounts of accumulation of DPM in the filter at various points of times during the engine running time;
• when the processing of data for one of the first and second sets of engine operating parameters discloses a value calling for regeneration of the filter, operating the engine in a mode of operation for forcing regeneration of the filter;
• and
• when a value resulting from subsequent processing of data for the one set of engine operating parameters discloses an amount of accumulation of DPM in the filter does not call for regeneration of the filter, discontinuing that mode of operation.

A method of imposing a forced regeneration cycle on a diesel particulate filter that treats exhaust gas passing through an exhaust system of a diesel engine to force regeneration of the filter, the method comprising:

• providing engine fueling data representing engine fueling in the absence of forced regeneration of the filter;
• as the forced regeneration cycle progresses, repeatedly processing both baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle and engine speed data that represents engine speed according to a map that correlates values representing various timings for engine fueling during the forced regeneration cycle with both values of baseline engine fueling and values of engine speed to yield timing values for the timing of engine fueling as the forced regeneration cycle progresses;
• processing data representing light off temperature of catalytic material of the filter and data representing actual temperature of the catalytic material, as the forced regeneration cycle progresses, to yield adjustment values for adjusting the timing values;
• processing the adjustment values and the timing values to yield adjusted timing values for the timing of engine fueling during the forced regeneration cycle;
• processing the adjusted timing values and the engine speed data according to a map that correlates fueling modification values with both the adjusted timing values and values of engine speed to yield fueling modification values;
• processing the engine fueling data and the fueling modification values to yield adjusted fueling values;
• using the adjusted fueling values instead of the engine fueling data for fueling the engine during the forced regeneration cycle;
• and
• using the adjusted timing values for the timing of engine fueling during the forced regeneration cycle.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data that represents engine speed, data that represents engine fueling, data that represents turbocharger boost, and data that represents exhaust gas recirculation (EGR) from the exhaust system back into the engine, through an engine emissions model to yield values representing rates at which diesel particulate matter (DPM) from the engine is entering the exhaust system and values for NOx concentration in the exhaust gas,
• b) repeatedly processes the values for NOx concentration in the exhaust gas, values representing concentration of O2 in the exhaust gas entering the filter, and values representing temperature of exhaust gas entering the filter through a DPM oxidation model to yield values of DPM oxidation rate data representing the rate at which DPM is being oxidized in the exhaust system,
• c) repeatedly processes the values of DPM oxidation rate data and the values representing a rate at which DPM from the engine is entering the exhaust system data through a DPM accumulation model to yield values of net DPM accumulation representing net accumulation of DPM in the filter at various points of time during engine running time,
• d) repeatedly processes accumulated engine running time through an ash accumulation model to yield data representing ash accumulation in the filter, and
• e) repeatedly processes the values of net DPM accumulation and the data representing ash accumulation in the filter through regeneration initiating/terminating logic for commanding a forced regeneration cycle when a result of the latter processing calls for initiation of forced regeneration of the filter and for discontinuing the forced regeneration cycle when a subsequent result calls for termination of the forced regeneration cycle.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data that represents parameters useful in determining a rate at which diesel particulate matter (DPM) is accumulating in the filter through a DPM accumulation model to yield values of DPM accumulation representing accumulation of DPM in the filter at various points of time during engine running time,
• b) processes the values of DPM accumulation and data that distinguishes DPM accumulation values calling for forced regeneration of the filter from those not calling for forced regeneration of the filter,
• c) when a result of the latter processing discloses that a DPM accumulation value calls for forced regeneration of the filter, initiates forced regeneration by retarding the timing of engine fueling to elevate the exhaust gas temperature to a temperature for forcing regeneration of the filter,
• d) as the forced regeneration cycle progresses, repeatedly processes baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle, engine speed data that represents engine speed, data representing light off temperature of catalytic material of the filter, and data representing actual temperature of the catalytic material, to yield adjusted timing values for timing of engine fueling and fueling modification values;
• processes engine fueling data that represents engine fueling in the absence of forced regeneration of the filter and the fueling modification values to yield adjusted fueling values;
• causes the adjusted fueling values instead of the engine fueling data to be used for fueling the engine during the forced regeneration cycle;
• and
• causes the adjusted timing values to be used for the timing of engine fueling during the forced regeneration cycle.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data that represents temperature of exhaust gas entering the filter, data that represents exhaust gas flow entering the filter, and data that utilizes both exhaust gas temperature and flow to distinguish a filter that has trapped an amount of diesel particulate matter (DPM) calling for forced regeneration from a filter that does not call for forced regeneration to yield result data that 1) calls for forced regeneration of the filter when the data that represents temperature of exhaust gas entering the filter and the data that represents exhaust gas flow entering the filter disclose that the filter has trapped an amount of DPM calling for forced regeneration, and 2) calls for no forced regeneration when the data that represents temperature of exhaust gas entering the filter and the data that represents exhaust gas flow entering the filter disclose that the filter does not call for regeneration,
• b) when the result data calls for forced regeneration of the filter, initiates forced regeneration by retarding the timing of engine fueling to elevate the exhaust gas temperature to a temperature for forcing regeneration of the filter,
• c) as the forced regeneration cycle progresses, repeatedly processes baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle, engine speed data that represents engine speed, data representing light off temperature of catalytic material of the filter, and data representing actual temperature of the catalytic material, to yield adjusted timing values for timing of engine fueling and fueling modification values,
• d) processes engine fueling data representing engine fueling in the absence of forced regeneration of the filter and the fueling modification values to yield adjusted fueling values,
• e) causes the adjusted fueling values instead of the engine fueling data to be used for fueling the engine during the forced regeneration cycle, and
• f) causes the adjusted timing values to be used for the timing of engine fueling during the forced regeneration cycle.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data that represents a rate at which diesel particulate matter (DPM) from the engine is entering the exhaust system, data that represents a rate at which DPM is being oxidized in the exhaust system, and data that represents DPM trapping efficiency of the filter, to yield values representing net rate at which DPM is being trapped in the filter at various points of times during the engine running time,
• b) processes the values representing net rate at which DPM is being trapped in the filter and data representing effective geometric size of DPM trapping medium in the filter to yield values representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium,
• c) processes the values representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium and data distinguishing values of DPM trapped in the filter per unit of geometric size of the DPM trapping medium that call for forced regeneration of the filter from those that do not call for forced regeneration, and
• d) when a result of the latter processing discloses that a value of data representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium calls for regeneration of the filter, causes the engine to operate in an elevated temperature mode of operation that elevates the exhaust gas temperature to a temperature for forcing regeneration of the filter, and
• e) when a subsequent result discloses that a value of data representing DPM trapped in the filter per unit of geometric size of the DPM trapping medium does not call for regeneration of the filter, causes discontinuance of operation of the engine in the elevated temperature mode of operation.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data for a first set of engine operating parameters to yield values representing amounts of accumulation of diesel particulate matter (DPM) in the filter at various points of times during the engine running time,
• b) during engine running time, repeatedly processes data for a second set of engine operating parameters different from the first set of engine operating parameters to yield values representing amounts of accumulation of DPM in the filter at various points of times during the engine running time,
• c) when the processing of data for one of the first and second sets of engine operating parameters discloses a value calling for regeneration of the filter, causes the engine to operate in a mode of operation for forcing regeneration of the filter, and
• d) when a value resulting from subsequent processing of data for the one set of engine operating parameters discloses an amount of accumulation of DPM in the filter does not call for regeneration of the filter, cause discontinuance of that mode of operation.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) as the forced regeneration cycle progresses, repeatedly processes both baseline engine fueling data representing engine fueling at commencement of the forced regeneration cycle and engine speed data that represents engine speed according to a map that correlates values representing various timings for engine fueling during the forced regeneration cycle with both values of baseline engine fueling and values of engine speed to yield timing values for the timing of engine fueling as the forced regeneration cycle progresses,
• b) processes data representing light off temperature of catalytic material of the filter and data representing actual temperature of the catalytic material, as the forced regeneration cycle progresses, to yield adjustment values for adjusting the timing values,
• c) processes the adjustment values and the timing values to yield adjusted timing values for the timing of engine fueling during the forced regeneration cycle,
• d) processes the adjusted timing values and the engine speed data according to a map that correlates fueling modification values with both the adjusted timing values and values of engine speed to yield fueling modification values,
• e) processes engine fueling data representing engine fueling in the absence of forced regeneration of the filter and the fueling modification values to yield adjusted fueling values,
• f) causes the adjusted fueling values instead of the engine fueling data to be used for fueling the engine during the forced regeneration cycle, and
• g) causes the adjusted timing values to be used for the timing of engine fueling during the forced regeneration cycle.

A turbocharged diesel engine comprising:

• an exhaust system comprising a diesel particulate filter that treats exhaust gas from the engine;
• and
• a control system for imposing a forced regeneration cycle on the diesel particulate filter to force regeneration of the filter, wherein the control system comprises a processor that
• a) during engine running time, repeatedly processes data that represents parameters useful in determining the concentration of NOx in exhaust gas entering the exhaust system from the engine to yield NOx concentration data for NOx concentration in the exhaust gas;
• and
• b) repeatedly processing 1) the NOx concentration data, 2) data representing concentration of O2 in the exhaust gas entering the filter, 3) data representing temperature of exhaust gas entering the filter, and 4) data for developing DPM oxidation rate data from NOx concentration data, O2 concentration data, and exhaust gas temperature data, to yield values of DPM oxidation rate data representing the rate at which DPM is being oxidized in the exhaust system.