Flow computational simulation and the performance study of a single phase pump-mixer

In this research, computational fluid dynamics (CFD) was used to undertake a numerical simulation of the influence of several design factors on the hydrodynamic performance of a pump-mixer, including the baffle and impeller clearance. For single phase flow simulation, the k-ε turbulence model as well as the multiple reference frame (MRF) were used. Results showed that the tangential flow in pump-mixer without baffles was dominant and led to poor mixing. The flow pattern in pump-mixer with baffles changed to axial flow that reduced the hydraulic head and increased the power consumption. The effects of three different clearances on the pump-mixer macroscopic parameters were also studied. The results indicated that the axial flow pattern changed to radial flow by increasing the clearance, which led to an increase in power consumption and a decrease in head. Power consumption at the clearance 135 and 200 mm, compared to the initial clearance of 82.5 mm, increased by 157 and 214% and the head also decreased by 47 and 58%, respectively.