Exhaust Emission Control in Medium Swirl Rate Direct Injection Diesel Engines

This paper reports test work conducted on a family of medium swirl, direct injection diesel engines in the 50-200 hp range, typical of those used in FCIM equipment. An analysis of emissions reporting techniques is discussed, including a comparison of on-highway and agricultural weighting factors for the 13 mode cycle. Naturally aspirated, turbocharged, and turbocharged-intercooled versions of a basic engine family are compared, along with possible emissions reductions by exhaust gas recirculation on a naturally aspirated engine and retarded injection timing on turbocharged engines. The increase in fuel cost for NO₂ reduction by retarded timing is presented.