The dynamics of gas fluctuations in a gas-liquid mixing vessel agitated by an axial pumping impeller near the full dispersion condition has been experimentally investigated. The transition region from full dispersion to partial dispersion has been identified in the plots of the specific power drawn with respects to the gas flow rate. The wavelet analysis performed on torque signal measurements revealed the existence of a competition between two dynamical systems-one representing vortex-type cavities and the other representing large gas-filled cavities. The fluctuation rate increased until it reached a maximum value at specific values of the flow number, and then decreased with further increase in the flow number. A space phase study revealed a transition from low amplitude oscillation attractor types to aperiodic attractor types as the flow number was increased. (c) 2005 Elsevier Ltd. All rights reserved.