Investigation of the Effects of Engine Design Parameters on Diesel Combustion and Emissions Using Taguchi Methods

The effects of changes in fuel spray cone angle, number of spray holes, nozzle hole area, nozzle tip protrusion, compression ratio, swirl level, and injection timing on Diesel combustion and emissions were investigated at three engine operating conditions using Taguchi design of experiment methods. The effects of changes in these design parameters on the ignition delay (ID), premixed combustion fraction (PCF), premixed combustion index (PCI), and diffusion combustion index (DCI) were examined along with their effects on particulates, NOx, hydrocarbons, and smoke emissions. The key design parameters affecting both the combustion process and the exhaust emissions were identified, and qualitative as well as quantitative relationships between the design parameters, combustion parameters, and exhaust emissions were established.