含转刷与推进器的全尺寸氧化沟流场模拟与DO分布  

Flow Field Simulation and DO Distribution in Full-scale Oxidation Ditch with Brushes and Propellers

作　　者：曾祥专 张金松 卢欢亮 黄志华 叶向东 汪永红 

机构地区：[1]广东省环境科学研究院,广东广州510045 [2]深圳水务集团,广东深圳518031

出　　处：《中国给水排水》2014年第9期104-108,共5页China Water & Wastewater

摘　　要：运用计算流体力学(CFD)数值模拟技术建立了包含转刷和推进器的氧化沟流场模拟模型,对于转刷的模拟,采用"两步法",首先模拟出单元转刷叶片转动所造成流场推流状况,并从中获得推流函数,然后以自定义函数(UDF)的形式将叶片旋转形成的流场扩展到整个转刷所在位置来实现对转刷的模拟。对于推进器,采用了船舶推进理论中的理想推进器模型来实现对推进器推流作用的模拟。两者结合可以对整个氧化沟的真实流态情况作出完整的模拟,经过修正后流场理论计算结果和实测值吻合情况良好。在流场模拟的基础上,运用组分输送模型对氧化沟中溶解氧的分布趋势进行了探索性模拟研究,结果表明深沟型氧化沟内溶解氧主要分布在沟体的上部,底部溶解氧的获得主要是由于弯道环流作用引起的,沟内溶解氧在纵向、横向、垂向的分布表现出一定的不均匀性和规律性。A simulation model for flow field in oxidation ditch with brushes and propellers was built using computational fluid dynamics. For the simulation of brushes, ＂two steps＂ method was used. The first step was to model the rotating brush. The second step was to model the whole ditch using results from the first step by using the UDF form. For the simulation of propellers, the notion of ideal eddy flow was introduced into the calculating field to reflect the drive power of submerged propellers. The two measures combined could create a complete simulation of the flow pattern of the ditch. Meanwhile, the theoretical calculation results coincided well with the measured results. Based on the simulation of flow field, the DO distribution was simulated using component transport model. The results indicated that DO was mainly distributed in the ditch＇ s upside, and the presence of DO in the bottom was mainly caused by the curve circulation. In the ditch, the dissolved oxygen distribution showed the imbalance and regularity in vertical, horizontal and longitudinal directions.

关 键 词：计算流体力学 氧化沟 转刷 水下推进器 流态分析 溶解氧分布 

分 类 号：X703[环境科学与工程—环境工程]