油束撞击法形成混合气在涡流室式柴油机上的应用

介绍了一种头部带挡块的轴针式喷油嘴在涡流室式柴油机上的应用。该喷嘴的特点是喷孔喷出的燃油直接撞击在挡块上，油束经挡块撞击在改变了方向的同时也产生油滴的二次雾化，从而达到既加大喷束与空气的接触面积，同时又限制了燃油喷进燃烧室中心的目的。发动机的台架试验表明，采用这种喷油嘴后，可以显著地改善原机的经济性和排放品质。在柴油机的标定工况下，比油耗和排气烟度分别降低４％和３０％。这种混合气形成方法为进一步提高柴油机的性能提供一个新的途径。

Application of Air/Fuel Mixture Formed by Fuel Spray Impingement to Diesel Engines

This paper reports the application of a pintle nozzle with a specially designed tip to a diesel engine with swirl chamber.The function of the nozzle is that the fuel spray direction is changed by the tip when the spray injected from the nozzle impinges on the tip directly,then the spray off the tip will be reatomized.Since those fully atomized fuel drops have larger surface contacted with air,the air utility inside the swirl chamber is improved,and the dissociation of fuel by the high temperature at center in chamber is avoided because of the role of tip to change spray direction.Experimental results on a testing bench showed that the engine performance could be remarkably improved if the special nozzle was installed on the engine.At the rating condition,the specific fuel consumption and exhaust smoke of the diesel engine with swirl chamber could be decreased by 4% and 30% respectively.The mixture formed by fuel impingement provides a new way for improvement of eninge performance.