Effects of ultrasound on micromixing in flow cell

Abstract This paper deals with the influence of ultrasound on micromixing in a continuous reactor of low reacting volume to confine the ultrasonic energy. A continuous 50 ml-cell was used. Residence time distribution has been determined to study macromixing and the Dushman reaction (iodide–iodate) coupled with a neutralization has been used as a test reaction to study the local state of micromixing. Measured product distributions with unpremixed feeds of differents, flow rates, and viscosities showed the influence of low-frequency ultrasonic power on micromixing (20 kHz). The incorporation model coupled with a dynamic model was used to determine the micromixing time in the reactor as a function of the segregation index. Thus these experiments show that the characteristic micromixing time can reach a magnitude of 0.001 s.

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