进气涡流对车用直喷式柴油机瞬态工况下微粒排放的影响

Effect of Intake Swirl on Particulate Emission from an Automotive D.I.Diesel Engine Under Transient Operating Conditions

用自行设计的喷气式可变涡流进气系统 ( AIVSIS)调节气缸内的涡流水平 ,试验研究了进气涡流对车用直喷式柴油机恒转速增转矩瞬态工况下微粒排放的影响。结果表明 ,对于一定涡流比的瞬态工况 ,随着转矩变化率的增大 ,柴油机的微粒排放量逐渐增加。涡流比越小 ,瞬态工况微粒的排放随转矩变化率增大的速率越高。相同转矩增长率的瞬态工况 ,随着涡流比的增大 ,柴油机微粒的排放量逐渐降低。提高恒转速增转矩瞬态工况气缸内的涡流强度 。

Effect of intake swirl on particulate emission from under an automotive D.I.diesel engine under transient operating conditions was experimentally studied.In-cylinder intake swirl was changed by means of a self-designed air injection variable swirl intake system (AIVSIS).Test results showed that in the event the engine speed is constant at every swirl ratio the particulate emission increases with the increase of engine torque increase rate.At transient operating conditions with the same torque increase rate,the particulate emission decreases with the increase of swirl ratio.In the case of higher swirl ratio transient operating conditions,particulate emission increase rate is smaller with the increase of engine torque increase rate.Particulate emission can be improved using AIVSIS to increase the swirl level in the cylinder for the engine transient operating conditions that engine speed is constant and torque is increased continuously.