多孔引燃柴油喷射器瞬态柴油初始喷雾过程模拟计算

摘要

采用模拟计算的方法对多孔引燃柴油喷射器瞬态柴油初始喷雾过程进行了研究 ,并利用纹影试验结果对计算模型进行了验证.研究结果表明 ,KHRT模型对多孔引燃柴油喷射器柴油初始喷雾的贯穿距和喷雾形状的预测与试验结果均较为吻合 ;柴油初始喷雾贯穿距随背压升高而减小 ,随环境温度的升高而增大 ;索特平均直径随背压的升高而降低 ,随环境温度的升高而增加 ;喷雾锥角随背压的升高而增大 ,随环境温度的升高而减小 ;因此背压较小 ,环境温度较低时柴油的引燃可靠性较高.%The spray transient characteristics of multi-hole pilot diesel injector were studied by numerical simulation and the computational model was verified with schlieren visualization method .The results indicated that the predicted spray penetration and spray shape of KHRT model were in good agreement with the experimental results .The penetration of initial diesel spray and Sauter mean diameter decreased with the increase of back pressure and increased with the rise of ambient temperature and the trend of spray cone angle were opposite .Accordingly ,the ignition reliability of diesel was high under the low back pressure and ambient temperature .