Steady and unsteady motion of one-component two-phase bubbly flow in 1-D Geometry

The aim of this work is to present a mathematical model of themotion of a one-component two-phase bubbly flow in one-dimensional geometry. Bubbles are assumed to be spherical and far enough from each other in order to exclude reciprocal interactions. The mathematical model is derived by means of a phase average operation and assuming a suitable description of the velocity field in the liquid phase, in the neighbourhood of the bubbles. Two different sets of experimental conditions are then simulated: a steady motion in a convergent–divergent nozzle and two different unsteady flows: i.e. two water hammer transients. Both the experimental conditions considered are well reproduced, indicating the validity of the proposed model.