In the present work, a new low-shear rotating reactor concept was introduced for process intensification of heterogeneous catalytic reactions in cocurrent gas-liquid downflow and upflow packed-bed reactors. To properly assess potential advantages of this new reactor concept, exhaustive hydrodynamic experiments were carried out using embedded low-intrusive wire mesh sensors. The effect of the rotational velocity on liquid flow patterns in the bed cross-section, liquid saturation, pressure drop, and regime transition was investigated. Furthermore, liquid residence time and Peclet number estimated by a stimulus-response technique and a macro-mixing model were presented and discussed with respect to the prevailing flow patterns. The results revealed that the column rotation induces different flow patterns in the cross-section of the packed bed operating in a concurrent downflow or upflow mode. Moreover, the new reactor concept exhibits a more flexible adjustment of pressure drop, liquid saturation, liquid residence time, and back-mixing at constant flow rates. (c) 2016 American Institute of Chemical Engineers AIChE J, 63: 283-294, 2017