In order to effectively implement DPF(Diesel Particulate Filters)regeneration control,thermal management of exhaust products before and inside Diesel Oxidation Catalyst(DOC)is necessary.In the present study,the Influe...In order to effectively implement DPF(Diesel Particulate Filters)regeneration control,thermal management of exhaust products before and inside Diesel Oxidation Catalyst(DOC)is necessary.In the present study,the Influence of the intake throttle valve and late post injection process on temperature rise inside DOC is analyzed through engine bench tests.The steady experiment results show that adjustment of the intake throttle valve can effectively increase exhaust temperature before DOC;in particular,with intake throttle valve opening at 20%,temperature before DOC can be increased by about 170℃ with respect to the full opening.An increase in the late post injection quantity can produce a significant rise of the temperature inside DOC,however its impact on the exhaust temperature before DOC is relatively limited.As the late post injection quantity increases,Hydrocarbon(HC)emissions also grow;in the present work it is shown that with a proper injection quantity,a considerable temperature increase inside the DOC can be obtained with relatively low HC emission.More specifically,with the intake throttle valve at 30%and DOC reaching ignition temperature as the late post injection quantity is increased,the exhaust temperature after DOC can be made larger than 550℃,adequate for DPF active regeneration.展开更多
文章针对柴油机微粒捕集器(diesel particulate filter,DPF)的再生展开相应的研究。利用降怠速再生试验(drop-to-idle,DTI)确定载体碳载量限值,利用台架试验研究了缸内次后喷(late post injection,LPI)基于不同再生温度与再生时间对再...文章针对柴油机微粒捕集器(diesel particulate filter,DPF)的再生展开相应的研究。利用降怠速再生试验(drop-to-idle,DTI)确定载体碳载量限值,利用台架试验研究了缸内次后喷(late post injection,LPI)基于不同再生温度与再生时间对再生效率和排放性能的影响。结果表明:3.0g/L的碳载量水平满足DTI的试验要求且适宜再生试验研究,可以避免在再生突然中断后DPF内部温度迅速升高,避免载体烧融;再生时间维持在2min左右,再生时DPF出口温度维持在500℃左右时,DPF再生效率高达98%,装载碳烟几乎完全燃烧,且DPF内部温度和出口温度可控,保证了DPF安全可靠再生,同时增加了DPF使用寿命;对整个再生过程中尾气成分进行分析和计算,发现柴油机尾气中HC为主要二次污染物,且排放相对较大。展开更多
基金supported by the Ministry of Science and Technology of the People’s Republic of China[grant numbers 2017YFC0211304]the Natural Science Foundation of Shandong Province[grant number ZR2019MEE041]the Open Fund of the National Engineering Laboratory for Mobile Source Emission Control Technology[grant number NELMS2017A14].
文摘In order to effectively implement DPF(Diesel Particulate Filters)regeneration control,thermal management of exhaust products before and inside Diesel Oxidation Catalyst(DOC)is necessary.In the present study,the Influence of the intake throttle valve and late post injection process on temperature rise inside DOC is analyzed through engine bench tests.The steady experiment results show that adjustment of the intake throttle valve can effectively increase exhaust temperature before DOC;in particular,with intake throttle valve opening at 20%,temperature before DOC can be increased by about 170℃ with respect to the full opening.An increase in the late post injection quantity can produce a significant rise of the temperature inside DOC,however its impact on the exhaust temperature before DOC is relatively limited.As the late post injection quantity increases,Hydrocarbon(HC)emissions also grow;in the present work it is shown that with a proper injection quantity,a considerable temperature increase inside the DOC can be obtained with relatively low HC emission.More specifically,with the intake throttle valve at 30%and DOC reaching ignition temperature as the late post injection quantity is increased,the exhaust temperature after DOC can be made larger than 550℃,adequate for DPF active regeneration.
文摘文章针对柴油机微粒捕集器(diesel particulate filter,DPF)的再生展开相应的研究。利用降怠速再生试验(drop-to-idle,DTI)确定载体碳载量限值,利用台架试验研究了缸内次后喷(late post injection,LPI)基于不同再生温度与再生时间对再生效率和排放性能的影响。结果表明:3.0g/L的碳载量水平满足DTI的试验要求且适宜再生试验研究,可以避免在再生突然中断后DPF内部温度迅速升高,避免载体烧融;再生时间维持在2min左右,再生时DPF出口温度维持在500℃左右时,DPF再生效率高达98%,装载碳烟几乎完全燃烧,且DPF内部温度和出口温度可控,保证了DPF安全可靠再生,同时增加了DPF使用寿命;对整个再生过程中尾气成分进行分析和计算,发现柴油机尾气中HC为主要二次污染物,且排放相对较大。