INVESTIGATION OF THE EFFECTS OF FUEL INJECTION NOZZLE PARAMETERS ON IGNITION DELAY IN DIESEL FUELS

摘要

Ignition delay of die sel fuels is a strong function of the chemical composition of the fuel. However, fuel injection nozzle parameters such as internal nozzle geometry, and nozzle spray pattern might also have a substantial effect on ignition delay. In order to understand these effects, ASTM test method D6890 was employed to measure the ignition delay of a single diesel reference fuel using several test nozzles. With the aid of test rigs that were developed, the nozzle parameters evaluated included internal nozzle geometry and nozzle spray pattern. The obtained geometry and spray characteristics of each of the test nozzles were then compared to their corresponding ignition delay values. The results of the investigation showed that nozzle pintle clearance has a strong effect on ignition delay, while nozzle spray pattern does not appear to have any effect on ignition delay as measured per ASTM D6890. Consistently, needle dimensions that drive the nozzle spray pattern did not appear to have any effect on ignition delay.