A Study of Exhaust and Noise Emissions Reduction on a Single Spray Direct Injection

Exhaust and noise emissions were successfully reduced using a Single Spray Direct Injection Diesel Engine (SSDI) on a two-liter naturally-aspirated four-cylinder engine. The compression ratio, the swirl ratio and the pumping rate were optimized to obtain good fuel economy, high power output and low exhaust emissions. Furthermore, through a modification of the fuel injection equipment, hydrocarbon (HC) emissions were reduced.

Upon a test vehicle evaluation of this engine, more than 11% fuel savings relative to Mazda two-liter Indirect Injection Diesel Engines (IDI) were obtained.

As for engine noise, structural modifications of the engine were carried out to obtain noise emission levels equivalent to IDI.