Optimization and Smoke Reduction Process in a D. I. Diesel Engine with Turbulence Generation Cell.

Significant smoke reduction characteristics were previously reported for a D.I. diesel engine which has a turbulence generation cell. This paper presents an optimization and smoke reduction prcess in an engine with a turbulence generation cell. The effects of the cell volume and fuel quantity injected into the cell were investigated. Gas sampling and in-cylinder observation were performed to elucidate particulate formation and oxidation processes in the cylinder. The results showed that the system reduced smoke through two mechanisms: (1) promotion of particulate oxidation by strong turbulence generated from the cell during the later stage of the combustion period, (2)decreased fuel quantity injected into the main chamber. For the reduction of smoke and fuel consumption, the cell volume and a fuel amount injected into the cell should be limited to about 5% of the clearance volume and to 10% of the total fuel, respectively. When a larger amount of fuel is injected into the cell, smoke emission increases due to an increased amount of particulates in the turbulence generation cell.