Combustion and Emission Analysis of Heavy-duty Vehicle Diesel Engine

Aiming at the research on combustion and emission characteristics of heavy-duty vehicle diesel engine, a bench test was carried out for PM and NOx emission for a certain type diesel engine under different speed and loads. Results shows that for this type of heavy-duty vehicle diesel engine, ignition delay is longer and the proportion of diffusion combustion increases under high speed of external characteristics conditions. Under the speed of 1400 r/min, ignition delay decreases with load increases, combustion duration shortened at first, then increases, the proportion of diffusion combustion increases. The ignition delay is longer and cylinder temperature is higher under lower speed external characteristics of diesel engine, the emissions of soot and NOx are heavier; with large load of external characteristics of diesel engine, the emissions of soot and NOx are heavy as well.