Combustion Noise and Ignition Delay in Diesel Engines

Tests have been carried out on a current prechamber Diesel engine in different running conditions by using ASTM secondary reference fuels and experimental fuels of different hydrocarbon type composition and cetane quality.

Combustion noise measurement was based on the detection of pressure oscillations or the engine head vibrations by means of FIAT electronic equipment.

Experimental results show that changes in fuel composition which do not affect ignition delay can produce different combustion noise levels. Furthermore combustion noise intensity was measured by changing engine speed and load.