Exhaust system and method for controlling an exhaust system

摘要

In one exemplary embodiment of the invention, a method for controlling an exhaust system includes determining an air to fuel ratio within a combustion chamber of an internal combustion engine, measuring a temperature of an exhaust gas flow from the internal combustion engine into the exhaust system and determining a specific heat for the exhaust gas flow in a first segment of the exhaust system based on the temperature of the exhaust gas flow from the internal combustion engine and the air to fuel ratio, wherein the first segment is upstream of the particulate filter. The method also includes determining a first temperature of the exhaust gas in the first segment based on the specific heat for the exhaust gas flow and selectively controlling a regeneration process for the particulate filter using the determined temperature of the exhaust gas at the selected location.

主权项

1. An exhaust system comprising:
a temperature sensor; a particulate filter downstream of the temperature sensor; and a controller coupled to the temperature sensor, the controller configured to perform a method, the method comprising:
determining an air to fuel ratio within a combustion chamber of an internal combustion engine;measuring a temperature of an exhaust gas from the internal combustion engine using the temperature sensor;separately determining a specific heat for each of a plurality of constituents of the exhaust gas in a first segment of the exhaust system based on the temperature of the exhaust gas from the internal combustion engine and the air to fuel ratio, wherein the first segment is upstream of the particulate filter;determining a specific heat for the exhaust gas by adding up the plurality of specific heats for the plurality of constituents of the exhaust gas;determining a first temperature of the exhaust gas in the first segment based on the specific heat for the exhaust gas;determining an energy needed to attain a desired temperature of the exhaust gas based on the specific heat and the first temperature; andselectively controlling a regeneration process for the particulate filter based on the determined energy in order to raise the temperature of the exhaust gas at an inlet of the particulate filter to the desired temperature, the regeneration process including at least one of: a post-injection of fuel into a cylinder, a hydrocarbon injection into the exhaust system and heating the particulate filter via a heating device.