[Emission Characteristics of Particulate Matter from Diesel Buses Meeting Different China Emission Standards Fueled...

Based on heavy chassis dynamometer, an experimental study was conducted in diesel buses compliant with China Ⅲ,Ⅳ,Ⅴ emissions standards respectively, fueled with three different blends of petroleum diesel/biodiesel (0%,5%and 10%, V/V biodiesel blends), which investigated the characteristics of particulate matter (PM) emission under CCBC driving cycle. Results of study showed that the total PM number and mass emission from China Ⅴ bus respectively decreased by 68.1%,56.2%,57.5% and 52.7%,64.8%, 88.5% compared to China Ⅲ bus. When compared to China Ⅳ bus, the PM mass emission decreased by 43.0%, 47.3% and 42.1%, while the number increased by 4.0%,7.6% and 14.7%. The nucleation mode PM emission of China Ⅲ bus was mainly from high-speed driving condition, while China Ⅳ and Ⅴ buses were from middle-low speed. The accumulation mode PM emissions of China Ⅲ, Ⅳ and V buses were all mainly from middle-low speed driving conditions. In relatively lower speed conditions, compared to China Ⅲ bus, the nucleation mode PM emissions of China Ⅳ and Ⅴ buses obviously decreased, so was accumulation mode PM. Compared to China Ⅳ bus, emission of China Ⅴ bus did not improve obviously and the nucleation mode PM emission even increased. In high-speed driving condition, the nucleation mode PM emission from China Ⅲ bus increased dramatically, while those from China Ⅴ and Ⅳ buses slightly increased. Meanwhile, the accumulation PM number and mass emission of China Ⅳ bus was obviously higher than those of China Ⅴ and Ⅲ buses. When fueled with B10, the relatively bigger sizes PM emission of China Ⅲ bus deteriorated rapidly, indicating that China Ⅲ bus was not suitable for fuel with high blending ratio of biodiesel.