汽车工程
汽車工程
기차공정
AUTOMOTIVE ENGINEERING
2014年
12期
1428-1432
,共5页
杜家坤%孙万臣%李强%王晓丹%李国良%赖春杰
杜傢坤%孫萬臣%李彊%王曉丹%李國良%賴春傑
두가곤%손만신%리강%왕효단%리국량%뢰춘걸
高压共轨柴油机%稳态工况%瞬态工况%微粒粒度分布
高壓共軌柴油機%穩態工況%瞬態工況%微粒粒度分佈
고압공궤시유궤%은태공황%순태공황%미립립도분포
high-pressure common-rail diesel engine%steady-state condition%transient condition%parti-cle size distribution
对高压共轨柴油机稳态与瞬态工况下的微粒排放粒度分布进行了实验研究。结果表明,高压共轨柴油机排气微粒粒径大部分处于250nm以内,超细微粒占绝大多数。稳态工况下,随负荷增加微粒数量浓度分布曲线峰值逐渐向大粒径方向移动,大负荷工况下峰值开始进入积聚态区域。在瞬态工况下,微粒粒度分布曲线呈单峰形态,平均数量浓度分布峰值位于核态区域,峰值区间为15~25nm。在同一负荷(当量比0.5)下,稳态工况的核态微粒的数量、表面积和体积浓度均较稳态工况大幅度上升;随着瞬变率的增大,核态微粒数量浓度增加而积聚态微粒数量浓度下降。
對高壓共軌柴油機穩態與瞬態工況下的微粒排放粒度分佈進行瞭實驗研究。結果錶明,高壓共軌柴油機排氣微粒粒徑大部分處于250nm以內,超細微粒佔絕大多數。穩態工況下,隨負荷增加微粒數量濃度分佈麯線峰值逐漸嚮大粒徑方嚮移動,大負荷工況下峰值開始進入積聚態區域。在瞬態工況下,微粒粒度分佈麯線呈單峰形態,平均數量濃度分佈峰值位于覈態區域,峰值區間為15~25nm。在同一負荷(噹量比0.5)下,穩態工況的覈態微粒的數量、錶麵積和體積濃度均較穩態工況大幅度上升;隨著瞬變率的增大,覈態微粒數量濃度增加而積聚態微粒數量濃度下降。
대고압공궤시유궤은태여순태공황하적미립배방립도분포진행료실험연구。결과표명,고압공궤시유궤배기미립립경대부분처우250nm이내,초세미립점절대다수。은태공황하,수부하증가미립수량농도분포곡선봉치축점향대립경방향이동,대부하공황하봉치개시진입적취태구역。재순태공황하,미립립도분포곡선정단봉형태,평균수량농도분포봉치위우핵태구역,봉치구간위15~25nm。재동일부하(당량비0.5)하,은태공황적핵태미립적수량、표면적화체적농도균교은태공황대폭도상승;수착순변솔적증대,핵태미립수량농도증가이적취태미립수량농도하강。
An experimental study is carried out on the particle size distribution of a high-pressure common-rail diesel engine in both steady-state and transient conditions. The results show that a large proportion of diesel par-ticle emission have a size below 250nm, the majority of which are ultrafine particles. In steady-state conditions, with the increase of engine load, the peak of particle number concentration distribution curve move toward the large size direction, and starts to enter the region of the accumulation mode at high load. In transient conditions, particle size distribution curve shows a single peak pattern, the peaks of average number concentration distribution curve fall into the interval of 15nm to 25nm in the nucleation mode region. At same load with a stoichiometric ratio of 0. 5, the number, surface area and volume concentrations of particles in transient conditions are all higher than those in steady-state conditions, and with the increase of transient rate, the number concentration of nucleation particles rises while that of accumulation particle falls.