Abstract:

Measured the emissions of total hydrogen carbonite (THC)、carbon monoxide (CO) and nitrogen oxides (NOx) from different light-duty vehicles to quantitatively evaluate the gaseous pollutants emissions from domestic light-duty vehicles in China. Tested the driving cycle’s emissions of 106 light-duty vehicles including
diesel, gasoline direct injection (GDI) and multi-point injection (MPI) gasoline vehicles on a chassis dynamometer with different emissions standards. The results show that the average emissions are 86% for THC and 65% for CO for the GDI gasoline vehicles at the stage 5 of the National Standard comparing to the values at the stage 4 of the National Standard with the NOx average emissions of those remaining the same at both stages of the National Standard. CO and NOx emissions increase largely due to the high-speed and long-acceleration working conditions during the ultra-high-speed stage of WLTC (world-wide harmonized light vehicles test cycle). CO and NOx emissions of ECE (economic commission for Europe) stage are higher than those during the stage of
EUDC (extra urban driving cycle) at cold conditions. The temperatures of engine water and catalyst play a great role on the conventional pollutant emissions from light-duty vehicles.

Key words: light-duty vehicle, emissions, gaseous pollutants, diesel vehicles, gasoline direct injection (GDI), multi-point injection (MPI) , chassis dynamometer test