EFFECT OF BLADE NUMBER ON MIXING IN AN AERATED STIRRED TANK.

In order to study the effect of blade number on gas dispersion in an aerated stirred tank, the cavity concept had been used to understand the dispersive mechanism of bubbles for the Rushton turbine with the blade numbers of 4, 6 and 8. The flow pattern as well as the turbulent fluctuating velocity was measured with a hot-film anemometer, and the volumetric mass transfer coefficient was measured by the sodium sulfite method simultaneously. Both theoretical and experimental results show that the average turbulent fluctuating velocity, which represents the mixing intensity of the system, can be represented by a formula.