With the rise of altitude the emissions of soot and CO from diesel engine markedly increase while NOx emission lowers.By providing oxygen-enriched gas with different volume fraction of oxygen φ( O2 ), the effects of oxygen-enriched intake air on the emission performance of engine are studied at full load and different altitudes (2 000, 3 000 and 4 000m above sea level).The results show that with oxygen-enriched intake air at high altitude,the emissions of soot and CO reduce significantly, the emission of HC slightly lowers but the emission of NOx rises.With the increase of altitude, the emission of NOx lowers at same φ ( O2 ), but still at higher level.Accordingly in applying oxygen-enriched intake air to engine at high altitude, φ( O2 ) should be controlled at low range.%随着海拔的增加,柴油发动机的碳烟和CO排放明显增加,NO<,x>排放降低.通过供应不同氧气体积分数ψ(O<,2>)的富氧气体,研究不同海拔高度(2 000、3 000和4 000m)时,富氧进气对发动机全负荷排放性能的影响.结果表明,富氧进气显著降低了高海拔发动机碳烟、CO的排放,略微降低了HC的排放,却增加了NO<,x>的排放.随着海拔的增加,同样ψ(O<,2>)的NO<,x>排放降低但仍处于较高的水平.因此,富氧进气在高海拔发动机上应用须控制ψ(O<,2>)在低富氧范围.
展开▼
