Configuration of a Premixer and Grooved Surface to Intensify the Micromixing Performance of a Spinning Disc Reactor

A premixer and grooved surface are designed to improve the micromixing performance of a spinning disc reactor (SDR). The inlets of the impinging jet provide an initial premixing of the two streams. The effects of premixing and grooved surface on the overall micromixing performance at different conditions are investigated systematically. The results show that premixing and trapezoidal groove surface could greatly intensify the global micromixing performance of SDR. Increasing the rotation speed and flow rate also significantly improves the micromixing effect. When the disc distance is lower than 0.80 mm, an extremely low inter disc distance deteriorates the micromixing. The effect of premixing on the micromixing performance of low viscosity streams is more significant than that of the spinning disc itself. However, for high viscosity streams, the micromixing performance strongly depends on the spinning disc. The flow patterns in the designed SDR were further studied. Three flow patterns, including film flow, film-filament transitional flow, and filament flow, were observed in SDR with a stator disc. High rotational speed, large disc spacing, and low volumetric flow rate are conducive to the formation of filament flow rather than film flow. Predicative dimensionless criteria for flow patterns were established. The results provide meaningful information for further intensifying the micromixing performance of SDR.