用喷气式可变涡流进气系统改善柴油机的排放性能

自行研制了一种向螺旋进气道内喷射空气的可变涡流进气系统——喷气式可变涡流进气系统，试验研究了该系统对柴油机排放特性的影响。结果表明，该系统在不影响进气充量系数的情况下，可以明显改变柴油机微粒和氮化物的排放量。其原因在于系统对气缸内涡流强度的改变，直接影响了燃烧与空气的混合、燃烧。对于涡流强度与燃料的燃烧不相匹配的发动机工况，喷气式可变涡流进气系统可以有效改善发动机的排放性能，缓解氮氧化物与微粒排放的矛盾。

Change the Exhaust Performance of a Diesel Engine by Means of Air Injection Variable Swirl System

A variable swirl system by means of air injection in the helical inlet passage was developed,and the influence of this system to the exhaust performance of diesel engine was stuidied.The test results showed that,without obvious increase of volumetric efficiency,this system is able to make obviously change to the particulate and NO x emission.The reason is the change of swirl strength in the cylinder.For some modes,of which the swirl is unsuitable to the fuel combustion,the air injection variable swirl system is a very effective method to improve the trade off between NO x and particulate emissions.