涡轮桨搅拌槽内混合过程的数值模拟

Numerical simulation of mixing process in a stirred tank with rushton turbine

文中采用FLUENT软件对六直叶涡轮桨搅拌槽内的混合过程进行了数值模拟 ,选用多重参考系法(MRF)及标准k ε模型 ,将速度场与浓度场方程分开进行求解 ,所得的混合时间的模拟结果与实验值相吻合。同时用计算机流体力学 (CFD)方法研究了不同的加料点、监测点位置及操作条件对混合时间的影响规律 ,模拟结果表明 :混合过程主要由搅拌槽内的流体流动所控制 ,混合时间与加料点及监测点位置密切相关。研究结果对于工业搅拌反应器的优化具有一定的参考意义。

Mechanically agitated reactors are widely used in many industrial processes and the mixing time is one of the key parameters to the reactor design. The mixing process in a stirred tank of 0.476m diameter with six-blade Rushton turbine (DT-6) was numerically simulated by using computational fluid dynamics (CFD) package FLUENT 6.0. The multi-reference frame (MRF) and standard k-ε turbulent model were used in the simulation. The mixing time predicted by CFD is in good agreement with the experimental data. The effects of tracer feeding and detecting positions on mixing time were investigated. The mixing process is dominated by the flow field in the stirred tank. The results are of importance to the optimum of industry stirred reactors.