Two-phase flow Investigation in a centrifugal rotor through particle image velocimetry

This work uses Particle Image Velocimetry (PIV) to calculate the liquid flow field in a radial centrifugal rotor operating with single and two-phase air-water flows. Different liquid and gas flow rates, as well as different rotating speeds, were tested. Results have shown that the liquid velocity presented slight changes, whereas the turbulent kinetic energy and the turbulent shear stress increased for a small gas volume fraction. However, increasing the mean bubble diameter at the intake has reduced the turbulent kinetic energy. This effect could be due to the energy absorption on the surface of the bubbles. Moreover, the turbulent has increased by increasing the liquid flow rate while keeping the gas flow rate fixed. The findings from this work shed light on the gas-phase effect over the liquid flow field, especially on bubble-induced turbulence. Furthermore, the results presented herein can be useful for numerical modeling validation and for improving models such as turbulence enhancement or suppression caused by bubbles.