This work employed the electrical conductance and response time technique to experimentally investigate the hydrodynamic characteristics of a rotor-stator reactor (RSR). The effects of various operating conditions such as the rotation speed, liquid volumetric flow rate and number of rotor-ring layers on the hydrodynamic characteristics were examined, and correlations to predict the hydrodynamic characteristics of RSR were established. Results show that the predicted results are in agreement with those of the experiment with deviations within 10%, thus indicating the feasibility of employing the correlations to predict the liquid average velocity, holdup and number of liquid droplets in RSR. (C) 2016 Elsevier B.V. All rights reserved.