卡鲁塞尔氧化沟液-固两相流动混合物模型与两相水力特性模拟

A fluid and solid two-phase flow model and modeling of a Carrousel oxidation ditch

采用CFD数值计算的方法研究了卡鲁塞尔氧化沟工艺的污水-污泥两相水力特性.将污泥沉降模型进行湍流影响修正后与两相湍流混合物模型耦合,建立了氧化沟液固两相湍流混合物模型,实现了垂向上液固两相运动的分离;利用计算流体软件Fluent对工业规模污水厂氧化沟的污水-污泥两相流速进行模拟,结果表明,两相流混合物模型较好地揭示了氧化沟内混合液流场和污泥的分布情况,污泥浓度与流速呈负相关.

The CFD numerical calculation method was used to investigate the hydrodynamic characteristics of the wastewater-sludge 2-phase flow in the Carrousel oxidation ditch. The sludge settling model was modified to include the turbulence effect. The modified model was coupled with the 2-phase turbulence mixture model to set up the fluid-solid turbulence model of the oxidation ditch, so that the vertical movement of the two phases, including fluid and solid, is separated. After computation with the Computational Fluid Dynamics （CFD） software package-FLUENT, the model was calibrated and applied to the 2-phase flow velocity in the oxidation ditch in a full scale wastewater treatment plant. The modeling results show that this model could reasonably model the 2-phase movement and predict the distribution of sludge in the oxidation ditch. The sludge concentration is negatively related to the flow rates.