Study on Oxidation Processes of Unburnt HC in Exhaust System of Spark Ignition Engines

This study focuses on the time history of the concentration of unburnt HC in an exhaust system of spark ignition engine. A mathematical model which can estimate gas temperature, and degree of oxidation in an exhaust system for given engine specifications and operating conditions is developed. This model is confirmed by experiment in which instantaneous HC concentrations are measured by using a fast sampling valve, and measurement of HC emissions in an exhaust pipe of a methane fueled engine.