DURABILITY OF LOW-EMISSIONS SMALL OFF-ROAD ENGINES

Hung-Li Chang, Ph.D.
California Environmental Protection Agency, Air Resources BoardThe purpose of this study was to determine whether catalyst technology could be applied to small off-road engines to provide 50% or greater reductions in hydrocarbons plus oxides of nitrogen (HC+NOx) emissions throughout the engines' useful lives. Low-emission engines were developed using three-way catalytic converters, passive secondary-air induction systems. Catalysts were integrated into the engine's mufflers, where feasible, to maintain a compact package. To enable HC oxidation under such rich conditions, a simple passive supplemental air induction system was developed. The main conclusions of this work are that catalyst technology can be successfully applied to small off-road engines; that such applications are durable; and that HC+NOx reductions of 50 – 70% were demonstrated over the useful lives of several small engines. The results of this program are significant because they show good catalyst performance can be achieved on small engines using the stock rich air/fuel calibration through the use of a novel supplementary air induction system.

Location: Kaprielian Hall (KAP) - 156

Audiences: Everyone Is Invited

Contact: Evangeline Reyes