An automotive vehicle includes an internal combustion engine that combusts an air/fuel mixture thereby generating exhaust gas containing particulate matter, and an exhaust after-treatment component that collects the particulate matter. A regeneration system burns off the collected particulate matter thereby regenerating the exhaust after-treatment component. A controller obtains a model of the combustion that is based on a kinetic controlled combustion phase and a mixing controlled combustion phase, and determines a point on the model with respect to current engine conditions that indicates an amount of the particulate matter in the exhaust gas.
展开▼