Carrousel氧化沟的三维流场模拟与分析

Simulation and analysis on three-dimensional flow field of Carrousel oxidation ditch

利用CFD的Fluent软件,采用标准的三维K-ε紊流模型,对桂林市七里店污水处理厂1#氧化沟的流场进行了数值模拟,对导流墙和推进器附近的流速进行了计算分析。结果表明,氧化沟下层流速较低,局部区域流速低于0.2 m/s。为了防止污泥沉降,应进一步降低推进器位置。能量损失分析表明,卡罗塞氧化沟能量损失主要来源于沿程摩擦损失和局部损失。可通过增加墙体光滑度、降低入口高度以及增加导流墙的曲率半径等措施减少能量损失,改善现有氧化沟的水力特征。

Using the Fluent CFD software, the flow field of 1# oxidation ditch in Guilin Qilidian Sewage Treatment Plant was simulated by three dimensional K-ε turbulence mathematical model. The velocities in the vicinity of guide wall and propeller were calculated and analyzed. The results showed that the bottom velocity was lower than 0.2 m/s in partial area of the oxidation ditch. To avoid the sludge deposition, the propellers should be installed at lower positions. Energy consumption analysis indicated that the energy of Carrousel oxidation ditch was mainly consumed by friction along the way and local loss. Smoothing the wall, reducing the height of en- trance and increasing curvature radius of guide wall could decrease the energy consumption, and thereby improve the hydraulic characteristics in the present oxidation ditch.