Nitrogen dioxide emission from diesel vehicles equipped with exhaust after treatment systems

摘要

Nitrogen dioxide (NO{sub}2) emission from recent diesel vehicles equipped with exhaust after treatment systems were measured using actual driving test cycles. Particulate and Nitrogen oxide (NO{sub}x) mass emissions from these vehicles were low relative to previous diesel vehicles without exhaust after treatment devices. However, NO{sub}2 mass emission increased compared to the older vehicles without exhaust after treatment systems because of higher NO{sub}2/NO{sub}x ratio. NO{sub}x mass emission level of DPF equipped vehicles is higher than the vehicle to meet the same exhaust emission standard without DPF because of increased NO{sub}x emission at the automatic DPF regeneration period.