在1台4缸高压共轨柴油机上,通过向柴油中掺混0%,10%,20%正丁醇(质量分数),研究了在不同进气氧浓度条件下,掺混燃料含氧量对柴油机燃烧特性与排放的影响规律.研究结果表明:进气氧体积分数处于20%~21%之间时,燃用3种燃料的滞燃期均不随氧浓度的变化而变化;随着掺混比例的增加,燃料中含氧量增加,这导致了滞燃期的增加,且随着进气氧浓度的降低,滞燃期受燃料性质的影响作用不断增强;随着燃料中含氧量增加,炭烟(Soot)排放逐渐减小;掺混燃料的含氧量对NOx排放的影响不明显,而对指示热效率的提升有积极作用,在进气氧体积分数小于15%时,燃料含氧量对指示热效率的促进作用减弱.%The effects of oxygen content in blended fuel on combustion and emission of diesel engine were researched under different intake oxygen concentration on a 4-cylinder high pressure common rail diesel engine by mixing 0% ,10% and 20%mass faction of n-butanol into diesel respectively .The results show that the ignition delay periods of three blended fuels keep al-most constant when the volume fraction of intake air oxygen is between 20% and 21% .The increase of blending ratio leads to the increase of oxygen content of blended fuel so that the ignition delay period prolongs .And the effects of fuel properties on ig-nition delay period increase with the decrease of oxygen volume fraction of intake air .In addition ,the increase of oxygen content improved soot emission and indicated thermal efficiency but had little influence on NOx emission .When the oxygen volume fraction of intake air is lower than 15% ,the active effect of oxygen content of blended fuel on indicated thermal efficiency weakens .
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