| 摘要:为明晰柴油多油束对撞和干涉下的喷雾与燃烧特性，通过定容燃烧弹，基于纹影法对比研究单油束、双油束和三油束对撞的喷雾和燃烧特性。试验中将喷射压力设置为100 MPa，环境压力设置为4 MPa，环境温度在喷雾和燃烧分析中设置为500 K和800 K。结果表明：对于喷雾特性，多油束的碰撞促进了喷雾之间的相互作用，有效改善了喷雾的雾化效果。随着油束数量的增加，喷雾撞击过程变得更加强烈，撞击喷雾可获得更大的气液相喷雾面积，液相面积占比减小，双油束、三油束液相面积占比相比单油束分别减小了7.5%与15.8%。在燃烧特性方面，随着油束数量的增加，达到火焰峰值面积的时间缩短，燃料燃烧后的火焰浮起长度、火焰面积、碳烟量增大。双油束与三油束火焰面积、碳烟排放量分别小于单油束的1/2和1/3，这说明多油束的撞击与干涉是改善发动机燃烧特性、减少发动机碳烟排放的有效方法。 |
| 关键词: 柴油机 共轨 多油束 喷雾 燃烧特性 |
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| Multi-Oil Jet Collision Spray and Combustion Characteristics of High Pressure Common Rail Diesel |
| CHEN Zhanming,CHAI Guoqing,HE Haibin,WU Jie,CHEN Hao |
| Ningbo C.S.I. Power & Machinery Group Co.， Ltd， Ningbo 315033， China;Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving， Xi′an， 710018， China |
| Abstract:In order to clarify the spray and combustion characteristics of diesel under multi-oil jet collision and interference，the spray and combustion characteristics of single，double and triple oil jet collision were studied by constant volume combustor based on Schlieren method.In the experiment，the injection pressure was set to 100 MPa，the ambient pressure was set to 4 MPa，and the ambient temperature in the spray and combustion analysis was set to 500 K and 800 K，respectively.The results show that for the spray characteristics，the collision of multiple-oil jets promotes the interaction between the sprays and improves the atomization effect effectively.With the increase of the number of oil jets，the spray impact process becomes more intense，resulting in a larger gas-liquid spray area and a smaller proportion of liquid spray area.The liquid phase area ratio of double and triple oil jets decreased by 7.5% and 15.8% respectively compared with that of single oil jet.As for combustion characteristics，with the increase of the number of oil jets，the time to reach the peak flame area is shortened，and the flame floating length，flame area and carbon smoke amount after fuel combustion are increased.The flame area and soot emission of double and three oil jets are less than 1/2 and 1/3 of that of single oil jet respectively，which indicates that the impact and interference of multi-oil jets is an effective method to improve combustion characteristics and reduce soot emission of engine. |
| Key words: diesel engine common rail multi-oil jet spray combustion characteristic |
