Emission Reduction Device for SULEV Vehicle Applications

This paper describes a cold start emission reduction system developed for a 3.0L V6 test vehicle in order to meet SULEV emission regulations. The emphasis of this research is how the system can be used to meet SULEV emission standards without the need for a heavily loaded catalyst. A fuel-vaporizing device has been developed that generates vaporized fuel to be consumed during engine start up. The device allows for lean A/F ratio control during engine start and idle and is called a Combustion Stabilizing Device (CSD). A vehicle with a CSD mounted to the engine was tested in an emission lab. The test vehicle resulted in approximately 50% HC emission reduction in the first 20s of engine startup and had a catalyst warm-up time to T₅₀ (50% converter efficiency) of less than 20s.