Abstract
Particle Number (PN) emissions from three hybrid passenger vehicles with gasoline engine were measured under various ambient temperature (-7℃~35℃). Test was conducted with WLTC mode without Ex-High part. PN emissions were evaluated with methodologies of certification tests in Europe (23 nm and 10 nm). Increased CO and PN emissions were observed where the enrichment control appeared, such as first cycle of cold mode at low ambient temperature. Other emissions of PN were observed during warming up process. Both emissions exhibited dependence to ambient temperature. These impacts of ambient air temperature are particular in cold mode test and negligible in hot mode test.
