Approach for aftertreatment system modeling and model identification
A system and approach for catalyst model parameter identification with modeling accomplished by an identification procedure that may incorporate a catalyst parameter identification procedure which may include determination of parameters for a catalyst device, specification of values for parameters and component level identification. Component level identification may be of a thermal model, adsorption and desorption, and chemistry. There may then be system level identification to get a final estimate of catalyst parameters.
1. A catalyst modeling mechanism comprising: a computer; an engine from which an engine model is developed and stored in the computer; and a catalyst device, connected to the engine, from which a catalyst model is developed and stored in the computer; and wherein:
the computer is configured to construct the catalyst model by an identification procedure;
the identification procedure comprises a catalyst parameter identification procedure, which the computer is configured to perform by:
determining catalyst parameters for the catalyst device;
specifying initial values for the catalyst parameters;
identifying components from flow bench data that permits preparation of exhaust gas composition from the engine; and
identifying system level details from data of the exhaust gas composition from the engine, using the identified components from flow bench data as a starting point for identifying system level details; further wherein a final set of parameters of the catalyst model is generated from the identifying of system level details.
2. The mechanism of claim 1 , wherein: component level identification comprises steady state identification and transient identification; and system level identification comprises steady state identification and transient identification.
3. A vehicle comprising the catalyst modeling mechanism of claim 1 , including each of the engine and catalyst device, and an engine control unit, the engine control unit being configure to apply the catalyst model operate the engine and the catalyst device to prevent release of a contaminant the catalyst device is configured to react with.
4. A method of catalyst modeling in a system that includes each of a computer; an engine from which an engine model is developed and stored in the computer; and a catalyst device, connected to the engine, from which a catalyst model is developed and stored in the computer; the method comprising using an identification procedure to accomplish the modelling, the identification procedure including a catalyst parameter identification procedure which comprises:
determining catalyst parameters for the catalyst device;
specifying initial values for the catalyst parameters;
identifying components from flow bench data that permits preparation of exhaust gas composition from the engine;
identifying system level details from data of the exhaust gas composition from the engine, using the identified components from flow bench data as a starting point for identifying system level details; and
generating a final set of parameters of the catalyst model from the identifying of system level details.
5. The method of claim 4 , wherein:
component level identification comprises steady state identification and transient identification; and
system level identification comprises steady state identification and transient identification.
6. The method of claim 4 , further comprising controlling operation of the catalyst device and engine using the computer by applying the catalyst model to prevent release of a contaminant the catalyst device is configured to react with.