GTL/柴油混合燃料发动机瞬态工况下微粒排放粒度分布特征

Effect of GTL-diesel blends fuel on particle size distribution in common-rail diesel engine transient emission

研究了高压共轨增压中冷柴油机燃用天然气转化制成的合成油(Gas to liquid,GTL)不同添加比例的混合燃料在恒转速增转矩瞬态工况下的微粒排放粒度分布特征,分析了工况瞬变率及GTL添加比例对于微粒排放粒度分布的影响。研究结果表明,随着恒转速增转矩工况瞬变率的减小,各种试验燃料的微粒排放总量及其随时间变化的增长率均有所降低。随着GTL添加比例的增加,微粒生成总量、核态微粒和超细微粒总数均有所下降,积聚态微粒的生成量在大粒径处稍有增加。在5s增转矩工况下,G20和G30的核态微粒数量明显减少,比国IV石化柴油分别降低了42%和20%。与石化柴油相比,不同瞬变率的增负荷工况下发动机排气中超细微粒和核态微粒的比例,G10燃料稍有增加,G20和G30均有显著降低。

An experimental investigation is conducted to evaluate the effects of using GTL fuel on the particle size distribution of a fully instrumented,turbocharged and intercooled,common-rail direct injection（CRDI） engine.The tests are conducted using diesel,GTL fuel and their blends,with the engine working over three transient cycles.The results show that the total particulate emission and their growth with the elapsed time reduce as the transient rate reduced during the three transient cycles.The total particles,nuclei mode particles and ultrafine particles have all reduced as the increase of GTL fuel to the blends,but it increases a small margin for the accumulation mode particles.The nuclei modes particles for G20 and G30 fuel decreased 42% and 20%,respectively,compared to the diesel fuel.The percentage of nuclei modes particles and ultrafine particles for G20 and G30 fuel have a conspicuous decrease,and it increase a small margin for the G10 fuel during all the transient cycles.