大型储罐清洗喷嘴的数值模拟研究

针对石油储罐机械清洗过程中射流发散严重、有效靶距过短、清洗效果差的问题,现将一种含中心体式喷嘴应用到储罐清洗中。运用Fluent软件对含中心体的储罐清洗喷嘴内外流场进行了数值模拟仿真,过程中选用K-ε紊流模型和SIMPLEC算法进行了数值计算,采用Mixture多相流模型和非结构化网格对含中心体喷嘴和圆柱形喷嘴进行了对比模拟评价。研究结果表明,含中心体喷嘴沿射流方向的轴心速度逐渐增大,射流在计算域内未发散,有效靶距得到了提高。相比于圆柱形喷嘴,含中心体的喷嘴出口截面射流半径缩小了13.7%,聚束性得到了提高,打击力得到了更好的保持,因而能更好地满足大型储罐清洗的要求。

Numerical simulation of large storage tank cleaning nozzles

Aiming at the problems that jet divergence is serious, the effective target distance is short and cleaning effect is poor in the process of mechanical cleaning of oil tank, a new type of nozzle which has center cylindrical was investigated. The numerical simulation of the flow field inside and outside the tank cleaning nozzle with center cylinder was carried on with the software of Fluent, the K-~turbulenee model was used to establish a mathematical model. The water jet structure was simulated by fluent arithmetic . The effects of nozzle which has a center cylinder and cylindrical nozzle were evaluated on the Mixture muhiphase flow model and unstructured mesh which used simulation evaluation. The results indicate that the speed of the nozzle with the center cylinder increases gradually along the stream direction, the jet does not diver- gence within the computational domain and the target distance is improved effectively. The exit jet radius of nozzle which has center cylinder is reduced by 13.7% compared with the cylindrical nozzle and the bunching of the jet is improved as well as the hitting power is better kept, so that it can meet the requirements of large storage tank cleaning better.