Flow and power characteristics of a two-stage inline axial flow rotor-stator mixer have been investigated via CFD simulation of the RANS equations. The realizable k-epsilon turbulence model with enhanced wall treatment was used to predict the mean velocity field, turbulent kinetic energy, and energy dissipation rate, as well as flow and power number. The results from different computational meshes are compared. The periodic behavior of throughput and torque is attributed to rotor position and shown to be related to number of blades and stator slots. The flow, power number, and energy dissipated in different fluid regions are reported for various backpressure operating conditions. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.