Centrifugal pumps are used in several industrial processes. It is common
the operation of this equipment with gas-liquid mixtures, which is the
case of the electrical submersible pumping artificial lift method used
in the oil industry. The increase of free gas fraction inside the pump
may lead to unstable operation and problems such as surging and gas
locking phenomena to occur. In this study a drift-flux model is proposed
for the gas-liquid flow subjected to centrifugal fields using the
impeller as an example. The model is closed with experimental data of
bubble diameter, displacements and velocities acquired via high-speed
camera at several different rotational speeds and gas mass flow rates
using water as the continuous medium. From the modeling and the forces
balance in the bubbles, a quantitative criterion for the start point of
surging and gas locking conditions was proposed.