柴油机孔式喷嘴内部空化现象的数值模拟

Numerical Simulation of Cavitation within Diesel Nozzle Orifice

采用Fluent软件的混合多相流模型和空化模型,对柴油机孔式喷油嘴稳定喷射时喷嘴内部的空化流动现象进行了数值模拟,得到了空穴在喷油嘴内的分布情况,进一步分析了喷孔直径和喷孔长径比等几何结构参数对喷孔内空穴分布的影响。结果表明,增加喷孔直径和提高喷孔长径比可以使空穴在喷孔出口截面上分布更为均匀。

The cavitation flow within a diesel nozzle orifice at steady spray of the diesel engine is numerically simulated by using a mixed multiphase flow model coupled with a cavitation model to obtain the cavities distributions. This paper analyzes further the effects of nozzle diameter and length-diameter ratio on the cavities distributions within the nozzle orifice. The simulation results show that a better uniform distribution of the cavities at the nozzle exit section can be presented by enlarging nozzle diameter and increasing lengthdiameter ratio.