车用柴油机燃用生物柴油的排放特性

Emission properties of diesel engine fueled with biodiesel

为了研究生物柴油对发动机排放污染物的影响,采用台架实验研究了直喷自然吸气式4缸柴油机使用纯柴油B0、混合燃料B10、B20和B30以及纯生物柴油B100的污染物排放特性,通过进行不同转速和扭矩工况台架实验,分析发动机负荷和转速对柴油机排放污染物的影响。实验结果表明,在所有实验工况下,使用生物柴油能减少柴油机THC、CO和PM排放,增加NOx排放,随着混合燃油中生物柴油掺混比例的升高,THC、CO、PM和NOx排放的变幅逐渐增大,THC和CO的排放不断降低,而NOx和PM的排放变化呈现trade-off关系,相同掺混比例下,PM降低的幅度都大于NOx增加的幅度。

In order to study the influence of biodiesel on engine emissions, bench tests were conducted to inves- tigate the engine emissions from a 4-cyclinder naturally aspirated direct-injection diesel engine fueled with neat diesel fuel B0, blended fuels B10, B20, B30, and neat biodiesel （B100）. Experiments were conducted on dif- ferent engine speed and torque conditions so that the influence of engine load and engine speed on the emissions could be identified. The results showed that under all test conditions, biodiesel reduced THC, CO, and PM e- missions from diesel engines but increased NOx emissions. An increase in biodiesel ratio in blended fuels caused an increase in the amplitude of emissions variations;the THC and CO emissions consistently decreased and NOx and PM emissions showed trade-off relations. At the same blending ratio, the amplitude of PM reduction was al- ways greater than that of the NOx increase.