Development of a direct-injection diesel engine with mixture formation by fuel spray impingement 2000-05-0102
The mixture formation by fuel spray impingement (OSKA system)
was applied to a small direct-injection diesel engine in order to
reduce the wall quenching- induced emissions, i.e., the emissions
of THC and soluble organic fractions (SOF).
Experiments were carried out using a single-cylinder engine,
fitted with various piston cavity geometries, ran under a wide
range of compression ratios and fuel injection specifications. The
piston cavity was designed as a centrally located reentrant type.
The combination of the high squish flow and the weak penetration of
the OSKA spray was very effective in reducing harmful emissions. A
short ignition delay, under the retarded fuel injection timing, was
obtained because of the high compression ratio. The OSKA DI diesel
engine showed reduced NOx, smoke, and THC emissions without
deterioration of the fuel consumption compared to modern DI diesel
engines used in automotive applications. While PM emissions were
partially reduced, simultaneous reduction of NOx and PM was not
Satoshi Kato, Hideaki Tanabe, Takeshi G. Sato, Kenshi Fujita
Kanazawa Institute of Technology, Gunma Univ., Fuji Heavy Industries Ltd.