Numerical Simulation of a New Adjustable Mixer

Abstract

This paper introduces a new mixing equipment. The numerical simulation and experiment have been done on the internal flow field and mixing effect of the new mixer and for a conventional Kenics static mixer. The exit mixing uniformity is used as an indicator to evaluate the two mixers’ mixing effect. For the adjustable mixer, when the blades angle increases, the mixing uniformity increases. But when absolute value of the angle passed 30°, the rate of increasing begins to slow down. For avoiding too much flow resistance in high workload, the new mixer’s blades rotating angle should be within ±30°. The production of high strength large scale shear eddies on the wake behind the swirl blades in the adjustable mixer is the key for the effective mixing of flocculant and raw water. According to the numerical simulation and industrial experiments, the new adjustable mixer not only can adjust blade angle to fit different working conditions, but also can quickly mix the raw water with flocculant in the pipe behind the blades. The new mixer’s mixing speed and mixing effect are both obviously better than the conventional Kenics static mixer.