Systems And Methods For Estimating Particulate Load In A Particulate Filter

• US 20100126144A1
• Filed: 11/26/2008
• Published: 05/27/2010
• Est. Priority Date: 11/26/2008
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Tandon, Pushkar, Heibel, Achim Karl-Erich, He, Suhao
• Granted Patent: US 8,161,738 B2
• Time in Patent Office: Days
• US Class Current: 60/286
• CPC Class Codes: F01N 13/0097 the purifying devices are arranged in a single housing
• CPC Class Codes: F01N 2560/06 the means being a temperature sensor
• CPC Class Codes: F01N 2560/07 the means being an exhaust gas flow rate or velocity meter or sensor, intake flow meters only when exclusively used to determine exhaust gas parameters
• CPC Class Codes: F01N 2560/08 the means being a pressure sensor
• CPC Class Codes: F01N 2560/14 having more than one sensor of one kind
• CPC Class Codes: F01N 3/0253 adding fuel to exhaust gases
• CPC Class Codes: F01N 3/035 with catalytic reactors , e.g. catalysed diesel particulate filters
• CPC Class Codes: F01N 3/103 Oxidation catalysts for HC and CO only
• CPC Class Codes: F01N 3/106 Auxiliary oxidation catalysts
• CPC Class Codes: F01N 9/002 of filter regeneration, e.g. detection of clogging
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method for regenerating a particulate filter may comprise determining a temperature, a flow rate, and a total pressure drop of an exhaust gas flowing through a particulate filter, and determining a corrected soot layer permeability. The method may further comprise calculating an estimated soot load of the particulate filter based on the total pressure drop and the corrected soot layer permeability, and causing regeneration of the particulate filter when the estimated soot load is greater than or equal to a threshold value.

Claims

1. A method for regenerating a particulate filter, comprising:

determining a temperature, a flow rate, and a total pressure drop of an exhaust gas flowing through a particulate filter;

determining a corrected soot layer permeability;

calculating an estimated soot load of the particulate filter based on the total pressure drop and the corrected soot layer permeability; and

causing regeneration of the particulate filter when the estimated soot load is greater than or equal to a threshold value.

2. The method of claim 1, wherein determining the total pressure drop of the exhaust gas comprises determining inlet contraction losses, outlet expansion losses, inlet channel losses, outlet channel losses and permeable layer losses of the exhaust gas.

3. The method of claim 1, wherein determining the corrected soot layer permeability comprises determining a Stokes-Cunningham correction factor to the soot layer permeability.

4. The method of claim 1, further comprising estimating an ash load of the particulate filter.

5. The method of claim 4, wherein estimating the ash load comprises estimating the ash load based on at least one of oil consumption and engine operating time.

6. The method of claim 1, further comprising determining an Euler number and a Reynolds number corresponding to the fluid flowing through the particulate filter, wherein calculating the estimated soot load further comprises calculating the estimated soot load based on the Euler number and the Reynolds number.

7. The method of claim 6, wherein calculating the estimated soot load comprises calculating the product Of the Euler number, the Reynolds number and the Stokes-Cunningham correction factor to the soot layer permeability.

8. The method of claim 1, wherein determining the total pressure drop, the flow rate, and the temperature comprises one of estimating the total pressure drop, the flow rate, and the temperature and measuring the total pressure drop, the flow rate, and the temperature.

9. The method of claim 1, further comprising applying at least one gate for estimating the soot load.

10. The method of claim 1, further comprising applying at least one filter for estimating the soot load.

11. The method of claim 1, further comprising applying one or more gates and filters for estimating the soot load.

12. A method for regenerating a particulate filter, comprising:

estimating a soot load in a particulate filter based on at least the particulate filter'"'"'s geometric properties, the particulate filter'"'"'s microstructural properties, a total pressure drop of exhaust gas flowing through the particulate filter, a flow rate of the exhaust gas flowing through the particulate filter, a temperature of the exhaust gas flowing through the particulate filter, and a Stokes-Cunningham correction factor to soot layer permeability;

comparing the estimated soot load to a threshold soot load; and

causing regeneration of the particulate filter when the estimated soot load is greater than or equal to the threshold soot load.

13. The method of claim 12, wherein estimating the soot load comprises calculating an instantaneous soot load during dynamic engine operating conditions.

14. The method of claim 12, further comprising applying one or more gates and filters for estimating the soot load.

15. A system for estimating soot load in a particulate filter, comprising:

at least one temperature sensor;

at least one pressure drop sensor; and

at least one controller configured to receive signals from the at least one temperature sensor and the at least one pressure drop sensor, the at least one controller being further configured to dynamically estimate a soot load in a particulate filter based on the signals, an exhaust gas flow rate, the particulate filter'"'"'s inlet contraction losses and outlet expansion losses, the particulate filter'"'"'s geometric and micro-structural properties, and a Stokes-Cunningham correction factor to soot layer permeability.

16. The system of claim 15, wherein the at least one controller is configured to estimate an ash load in the particulate filter.

17. The system of claim 16, wherein the at least one controller is configured to estimate the ash load based on at least one of engine operating time and oil consumption.

18. The system of claim 16, wherein the at least one controller is configured to update parameters used for soot load estimation when a change in the estimated ash load is greater than or equal to a threshold value.

19. The system of claim 15, wherein the at least one controller is configured to generate at least one response signal causing regeneration of the particulate filter when the estimated soot load is greater than or equal to a threshold value.

20. The system of claim 15, wherein the at least one controller is configured to apply at least one gate to estimate the soot load.

21. The system of claim 15, wherein the at least one controller is configured to apply at least one filter to estimate the soot load.

22. The system of claim 15, wherein the at least one controller is configured to apply one or more gates and filters to estimate the soot load.

23. A method for regenerating a particulate filter, comprising:

determining a temperature, a flow rate, and a pressure drop of an exhaust gas flowing through a particulate filter;

determining a corrected soot layer permeability without using empirically derived values;

calculating an estimated soot load of the particulate filter based on the pressure drop and the corrected soot layer permeability; and

causing regeneration of the particulate filter when the estimated soot load is greater than or equal to a threshold value.

24. The method of claim 23, wherein determining the pressure drop of the exhaust gas flowing through the particulate filter comprises determining a total pressure drop of the exhaust gas flowing through the particulate filter.

25. The method of claim 23, further comprising estimating an ash load of the particulate filter.