Exhaust system and method for controlling temperature of exhaust gas in an exhaust system

A method for controlling temperature of exhaust gas in an exhaust system of an internal combustion engine, the method comprising:

• determining a flow rate of the exhaust gas;
• determining a temperature of the exhaust gas received by the exhaust system;
• determining a space velocity of the exhaust gas at an inlet of an oxidation catalyst;
• determining a temperature of the exhaust gas at the inlet of the oxidation catalyst;
• determining an amount of energy to be provided by each of a post-injection process using a fuel system coupled to a cylinder of the internal combustion engine, a hydrocarbon injector in the exhaust system, and a heating device proximate a particulate filter, wherein the amount of energy to be provided is based on a desired temperature at a selected location in the exhaust system, the flow rate of the exhaust gas, the temperature of the exhaust gas received by the exhaust system, the flow rate of the exhaust gas at the inlet of the oxidation catalyst and the temperature of the exhaust gas at the inlet of the oxidation catalyst;
• and
• communicating at least one of:
• a signal to control an amount of fuel to the exhaust gas in the cylinder corresponding to the amount of energy to be provided by the post-injection process, a signal to control an amount of fuel from the hydrocarbon injector to the exhaust system corresponding to the amount of energy to be provided by the hydrocarbon injector and a signal to control a current sent to the heating device corresponding to the amount of energy to be provided by the heating device.

An exhaust system comprising:

• a passage to receive an exhaust gas from a cylinder of an engine and to direct the exhaust gas to an oxidation catalyst;
• a particulate filter downstream of the oxidation catalyst;
• a hydrocarbon injector upstream of the particulate filter;
• a heating device configured to heat exhaust gas in the particulate filter;
• and
• a control module programmed to:
• determine an amount of energy to be provided to the exhaust gas achieve a desired temperature at the particulate filter;
• determine the energy available from a post-injection process using a fuel system, the hydrocarbon injector, and the heating device that can be utilized to achieve the desired temperature;
• and
• determine a distribution of the energy available from the post-injection process, the hydrocarbon injector, and the heating device, the achieve the desired temperature.