燃油增压锅炉配风器三维流动特性数值计算

采用RNGκ-ε模型,对船用燃油增压锅炉配风器流场进行了三维冷态数值模拟研究。将常温常压工况下的数值计算结果与PIV试验值进行了对比,两者结果的一致说明了计算模型的正确性。用此计算模型计算并对比了100%BMCR和50%BMCR两个工况下的流场,结果表明:垂直轴的截面上无量纲切向速度与无量纲轴向速度分布呈"M"型,但受稳焰器小孔非轴对称性的影响,无量纲切向速度轴对称性不强。相对于100%BMCR工况,50%BMCR工况回流区轴向和径向尺寸分别下降1.59%、4.55%,最大回流速度下降53%,压损下降75%。两工况下压降的模拟计算值与经验公式计算值均一致,计算结果为配风器的设计和优化运行提供参考依据。

Three-dimensional numerical research of air distributed organ in oil-fired supercharged boiler

RNGκ-ε model was employed to simulate the three dimensional flow field of the marine oil-fired boiler.The results of numerical computation which was taken under the normal condition(0.101MPa,20℃)were compared with PIV experimental results.The agreement of radial scale and pressure drop proved the reliability of the computation model used in this paper.This model was then applied in the running conditions: 100%BMCR and 50%BMCR.On the plane perpendicular to axis,they both have the similar M-shaped dimensionless tangential and axial velocity profile.But there is weak symmetry for tangential profile due to the asymmetrical distribution holes in the bluff-body.Compared with 100%BMCR,the axial and radial scale of 50%BMCR decreased by 1.59% and 4.55%,the maximum reflux speed decreased by 53%,and the pressure drop decreased by 75%.The pressure drop computed by simulation agreed well with empirical formula results.This paper can provide reference for the design and optimization of the air-distributed organ.